* Re: [PATCH iproute2] iplink_vxlan: take into account preferred_family creating vxlan device
From: Lorenzo Bianconi @ 2018-09-21 16:35 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: netdev
In-Reply-To: <20180921085805.7ee078e8@xeon-e3>
> On Fri, 21 Sep 2018 15:34:25 +0200
> Lorenzo Bianconi <lorenzo.bianconi@redhat.com> wrote:
>
> > Take into account the configured preferred_family if neither saddr or
> > daddr are provided since otherwise vxlan kernel module will use IPv4 as
> > default remote inet family neglecting the one provided by userspace.
> > This behaviour was originally in commit 97d564b90ccb ("vxlan: use
> > preferred address family when neither group or remote is specified").
> > The issue can be triggered with the following reproducer:
> >
> > $ip -6 link add vxlan1 type vxlan id 42 dev enp0s2 \
> > proxy nolearning l2miss l3miss
> > $bridge fdb add 46:47:1f:a7:1c:25 dev vxlan1 dst 2000::2
> > RTNETLINK answers: Address family not supported by protocol
> >
> > Fixes: 1e9b8072de2c ("iplink_vxlan: Get rid of inet_get_addr()")
> > Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
>
> This patch was already in the queue. Is this a new version (if so please mark it as v2).
Hi Stephen,
yes, this is a v2. I missed v2 in the subject and changes respect to v1
(I have just modified the commit log actually). Please drop v1 and sorry for
the noise.
Regards,
Lorenzo
>
^ permalink raw reply
* [PATCH bpf-next] bpftool: add support for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY maps
From: Roman Gushchin @ 2018-09-21 22:47 UTC (permalink / raw)
To: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Kernel Team, Roman Gushchin,
Alexei Starovoitov, Daniel Borkmann, Jakub Kicinski,
Yonghong Song
Add BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map type to the list
of maps types which bpftool recognizes.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Yonghong Song <yhs@fb.com>
---
tools/bpf/bpftool/map.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index af8ad32fa6e9..e22fbe8b975f 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -71,6 +71,7 @@ static const char * const map_type_name[] = {
[BPF_MAP_TYPE_XSKMAP] = "xskmap",
[BPF_MAP_TYPE_SOCKHASH] = "sockhash",
[BPF_MAP_TYPE_CGROUP_STORAGE] = "cgroup_storage",
+ [BPF_MAP_TYPE_REUSEPORT_SOCKARRAY] = "reuseport_sockarray",
};
static bool map_is_per_cpu(__u32 type)
--
2.17.1
^ permalink raw reply related
* Re: [PATCH net] af_key: free SKBs under RCU protection
From: stranche @ 2018-09-21 17:09 UTC (permalink / raw)
To: Eric Dumazet; +Cc: netdev, steffen.klassert
In-Reply-To: <6f2e6b62-42dc-f2b3-3758-29f5338f1185@gmail.com>
>>
>> As long as one skb has sock_rfree has its destructor, the socket
>> attached to
>> this skb can not be released. There is no race here.
>>
>> Note that skb_clone() does not propagate the destructor.
>>
>> The issue here is that in the rcu lookup, we can find a socket that
>> has been
>> dismantled, with a 0 refcount.
>>
>> We must not use sock_hold() in this case, since we are not sure the
>> socket refcount is not already 0.
>>
>> pfkey_broadcast() and pfkey_broadcast_one() violate basic RCU rules.
>>
>> When in a RCU lookup, one want to increment an object refcount, it
>> needs
>> to be extra-careful, as I did in my proposal.
>>
>> Note that the race could be automatically detected with
>> CONFIG_REFCOUNT_FULL=y
>
> Bug was added in commit 7f6b9dbd5afb ("af_key: locking change")
Hi Eric,
I tried your refcount idea below, but it still results in the same
crash.
>>>> --- a/net/key/af_key.c
>>>> +++ b/net/key/af_key.c
>>>> @@ -201,7 +201,9 @@ static int pfkey_broadcast_one(struct sk_buff
>>>> *skb, struct sk_buff **skb2,
>>>> {
>>>> int err = -ENOBUFS;
>>>>
>>>> - sock_hold(sk);
>>>> + if (!refcount_inc_not_zero(&sk->sk_refcnt))
>>>> + return -ENOENT;
>>>> +
>>>> if (*skb2 == NULL) {
>>>> if (refcount_read(&skb->users) != 1) {
>>>> *skb2 = skb_clone(skb, allocation);
I also tried reverting 7f6b9dbd5afb ("af_key: locking change") and
running the
test there and I still see the crash, so it doesn't seem to be an RCU
specific
issue.
Is there anything else that could be causing this?
^ permalink raw reply
* [PATCHv2 bpf-next 00/11] Add socket lookup support
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
This series proposes a new helper for the BPF API which allows BPF programs to
perform lookups for sockets in a network namespace. This would allow programs
to determine early on in processing whether the stack is expecting to receive
the packet, and perform some action (eg drop, forward somewhere) based on this
information.
The series is structured roughly into:
* Misc refactor
* Add the socket pointer type
* Add reference tracking to ensure that socket references are freed
* Extend the BPF API to add sk_lookup_xxx() / sk_release() functions
* Add tests/documentation
The helper proposed in this series includes a parameter for a tuple which must
be filled in by the caller to determine the socket to look up. The simplest
case would be filling with the contents of the packet, ie mapping the packet's
5-tuple into the parameter. In common cases, it may alternatively be useful to
reverse the direction of the tuple and perform a lookup, to find the socket
that initiates this connection; and if the BPF program ever performs a form of
IP address translation, it may further be useful to be able to look up
arbitrary tuples that are not based upon the packet, but instead based on state
held in BPF maps or hardcoded in the BPF program.
Currently, access into the socket's fields are limited to those which are
otherwise already accessible, and are restricted to read-only access.
Changes since v1:
* Limit netns_id field to 32 bits
* Reuse reg_type_mismatch() in more places
* Reduce the number of passes at convert_ctx_access()
* Replace ptr_id defensive coding when releasing reference state with an
internal error (-EFAULT)
* Rework 'struct bpf_sock_tuple' to allow passing a packet pointer
* Allow direct packet access from helper
* Fix compile error with CONFIG_IPV6 enabled
* Improve commit messages
Changes since RFC:
* Split up sk_lookup() into sk_lookup_tcp(), sk_lookup_udp().
* Only take references on the socket when necessary.
* Make sk_release() only free the socket reference in this case.
* Fix some runtime reference leaks:
* Disallow BPF_LD_[ABS|IND] instructions while holding a reference.
* Disallow bpf_tail_call() while holding a reference.
* Prevent the same instruction being used for reference and other
pointer type.
* Simplify locating copies of a reference during helper calls by caching
the pointer id from the caller.
* Fix kbuild compilation warnings with particular configs.
* Improve code comments describing the new verifier pieces.
* Testing courtesy of Nitin
* Rebase
This tree is also available at:
https://github.com/joestringer/linux/commits/submit/sk-lookup-v2
Joe Stringer (11):
bpf: Add iterator for spilled registers
bpf: Simplify ptr_min_max_vals adjustment
bpf: Generalize ptr_or_null regs check
bpf: Add PTR_TO_SOCKET verifier type
bpf: Macrofy stack state copy
bpf: Add reference tracking to verifier
bpf: Add helper to retrieve socket in BPF
selftests/bpf: Add tests for reference tracking
libbpf: Support loading individual progs
selftests/bpf: Add C tests for reference tracking
Documentation: Describe bpf reference tracking
Documentation/networking/filter.txt | 64 ++
include/linux/bpf.h | 17 +
include/linux/bpf_verifier.h | 37 +-
include/uapi/linux/bpf.h | 57 +-
kernel/bpf/verifier.c | 594 ++++++++++++++----
net/core/filter.c | 179 +++++-
tools/include/uapi/linux/bpf.h | 57 +-
tools/lib/bpf/libbpf.c | 4 +-
tools/lib/bpf/libbpf.h | 3 +
tools/testing/selftests/bpf/Makefile | 2 +-
tools/testing/selftests/bpf/bpf_helpers.h | 12 +
tools/testing/selftests/bpf/test_progs.c | 38 ++
.../selftests/bpf/test_sk_lookup_kern.c | 137 ++++
tools/testing/selftests/bpf/test_verifier.c | 373 ++++++++++-
14 files changed, 1441 insertions(+), 133 deletions(-)
create mode 100644 tools/testing/selftests/bpf/test_sk_lookup_kern.c
--
2.17.1
^ permalink raw reply
* [PATCHv2 bpf-next 01/11] bpf: Add iterator for spilled registers
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Add this iterator for spilled registers, it concentrates the details of
how to get the current frame's spilled registers into a single macro
while clarifying the intention of the code which is calling the macro.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
include/linux/bpf_verifier.h | 11 +++++++++++
kernel/bpf/verifier.c | 16 +++++++---------
2 files changed, 18 insertions(+), 9 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index b42b60a83e19..af262b97f586 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -131,6 +131,17 @@ struct bpf_verifier_state {
u32 curframe;
};
+#define __get_spilled_reg(slot, frame) \
+ (((slot < frame->allocated_stack / BPF_REG_SIZE) && \
+ (frame->stack[slot].slot_type[0] == STACK_SPILL)) \
+ ? &frame->stack[slot].spilled_ptr : NULL)
+
+/* Iterate over 'frame', setting 'reg' to either NULL or a spilled register. */
+#define for_each_spilled_reg(iter, frame, reg) \
+ for (iter = 0, reg = __get_spilled_reg(iter, frame); \
+ iter < frame->allocated_stack / BPF_REG_SIZE; \
+ iter++, reg = __get_spilled_reg(iter, frame))
+
/* linked list of verifier states used to prune search */
struct bpf_verifier_state_list {
struct bpf_verifier_state state;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 8ccbff4fff93..62ce45d9c558 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2250,10 +2250,9 @@ static void __clear_all_pkt_pointers(struct bpf_verifier_env *env,
if (reg_is_pkt_pointer_any(®s[i]))
mark_reg_unknown(env, regs, i);
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] != STACK_SPILL)
+ for_each_spilled_reg(i, state, reg) {
+ if (!reg)
continue;
- reg = &state->stack[i].spilled_ptr;
if (reg_is_pkt_pointer_any(reg))
__mark_reg_unknown(reg);
}
@@ -3393,10 +3392,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *vstate,
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] != STACK_SPILL)
+ for_each_spilled_reg(i, state, reg) {
+ if (!reg)
continue;
- reg = &state->stack[i].spilled_ptr;
if (reg->type == type && reg->id == dst_reg->id)
reg->range = max(reg->range, new_range);
}
@@ -3641,7 +3639,7 @@ static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno,
bool is_null)
{
struct bpf_func_state *state = vstate->frame[vstate->curframe];
- struct bpf_reg_state *regs = state->regs;
+ struct bpf_reg_state *reg, *regs = state->regs;
u32 id = regs[regno].id;
int i, j;
@@ -3650,8 +3648,8 @@ static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno,
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] != STACK_SPILL)
+ for_each_spilled_reg(i, state, reg) {
+ if (!reg)
continue;
mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null);
}
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 02/11] bpf: Simplify ptr_min_max_vals adjustment
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
An upcoming commit will add another two pointer types that need very
similar behaviour, so generalise this function now.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
kernel/bpf/verifier.c | 22 ++++++++++-----------
tools/testing/selftests/bpf/test_verifier.c | 14 ++++++-------
2 files changed, 17 insertions(+), 19 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 62ce45d9c558..a889398ba43d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2667,20 +2667,18 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
return -EACCES;
}
- if (ptr_reg->type == PTR_TO_MAP_VALUE_OR_NULL) {
- verbose(env, "R%d pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL prohibited, null-check it first\n",
- dst);
- return -EACCES;
- }
- if (ptr_reg->type == CONST_PTR_TO_MAP) {
- verbose(env, "R%d pointer arithmetic on CONST_PTR_TO_MAP prohibited\n",
- dst);
+ switch (ptr_reg->type) {
+ case PTR_TO_MAP_VALUE_OR_NULL:
+ verbose(env, "R%d pointer arithmetic on %s prohibited, null-check it first\n",
+ dst, reg_type_str[ptr_reg->type]);
return -EACCES;
- }
- if (ptr_reg->type == PTR_TO_PACKET_END) {
- verbose(env, "R%d pointer arithmetic on PTR_TO_PACKET_END prohibited\n",
- dst);
+ case CONST_PTR_TO_MAP:
+ case PTR_TO_PACKET_END:
+ verbose(env, "R%d pointer arithmetic on %s prohibited\n",
+ dst, reg_type_str[ptr_reg->type]);
return -EACCES;
+ default:
+ break;
}
/* In case of 'scalar += pointer', dst_reg inherits pointer type and id.
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 67c412d19c09..ceb55a9f3da9 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -3637,7 +3637,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
- .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END",
+ .errstr = "R3 pointer arithmetic on pkt_end",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
@@ -4780,7 +4780,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 4 },
- .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL",
+ .errstr = "R4 pointer arithmetic on map_value_or_null",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS
},
@@ -4801,7 +4801,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 4 },
- .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL",
+ .errstr = "R4 pointer arithmetic on map_value_or_null",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS
},
@@ -4822,7 +4822,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 4 },
- .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL",
+ .errstr = "R4 pointer arithmetic on map_value_or_null",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS
},
@@ -7137,7 +7137,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map_in_map = { 3 },
- .errstr = "R1 pointer arithmetic on CONST_PTR_TO_MAP prohibited",
+ .errstr = "R1 pointer arithmetic on map_ptr prohibited",
.result = REJECT,
},
{
@@ -8811,7 +8811,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
- .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END",
+ .errstr = "R3 pointer arithmetic on pkt_end",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_XDP,
},
@@ -8830,7 +8830,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
- .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END",
+ .errstr = "R3 pointer arithmetic on pkt_end",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_XDP,
},
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 03/11] bpf: Generalize ptr_or_null regs check
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
This check will be reused by an upcoming commit for conditional jump
checks for sockets. Refactor it a bit to simplify the later commit.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
kernel/bpf/verifier.c | 43 +++++++++++++++++++++++++------------------
1 file changed, 25 insertions(+), 18 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index a889398ba43d..7dccb18ede03 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -249,6 +249,11 @@ static bool type_is_pkt_pointer(enum bpf_reg_type type)
type == PTR_TO_PACKET_META;
}
+static bool reg_type_may_be_null(enum bpf_reg_type type)
+{
+ return type == PTR_TO_MAP_VALUE_OR_NULL;
+}
+
/* string representation of 'enum bpf_reg_type' */
static const char * const reg_type_str[] = {
[NOT_INIT] = "?",
@@ -3598,12 +3603,10 @@ static void reg_combine_min_max(struct bpf_reg_state *true_src,
}
}
-static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,
- bool is_null)
+static void mark_ptr_or_null_reg(struct bpf_reg_state *reg, u32 id,
+ bool is_null)
{
- struct bpf_reg_state *reg = ®s[regno];
-
- if (reg->type == PTR_TO_MAP_VALUE_OR_NULL && reg->id == id) {
+ if (reg_type_may_be_null(reg->type) && reg->id == id) {
/* Old offset (both fixed and variable parts) should
* have been known-zero, because we don't allow pointer
* arithmetic on pointers that might be NULL.
@@ -3616,11 +3619,13 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,
}
if (is_null) {
reg->type = SCALAR_VALUE;
- } else if (reg->map_ptr->inner_map_meta) {
- reg->type = CONST_PTR_TO_MAP;
- reg->map_ptr = reg->map_ptr->inner_map_meta;
- } else {
- reg->type = PTR_TO_MAP_VALUE;
+ } else if (reg->type == PTR_TO_MAP_VALUE_OR_NULL) {
+ if (reg->map_ptr->inner_map_meta) {
+ reg->type = CONST_PTR_TO_MAP;
+ reg->map_ptr = reg->map_ptr->inner_map_meta;
+ } else {
+ reg->type = PTR_TO_MAP_VALUE;
+ }
}
/* We don't need id from this point onwards anymore, thus we
* should better reset it, so that state pruning has chances
@@ -3633,8 +3638,8 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,
/* The logic is similar to find_good_pkt_pointers(), both could eventually
* be folded together at some point.
*/
-static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno,
- bool is_null)
+static void mark_ptr_or_null_regs(struct bpf_verifier_state *vstate, u32 regno,
+ bool is_null)
{
struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *reg, *regs = state->regs;
@@ -3642,14 +3647,14 @@ static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno,
int i, j;
for (i = 0; i < MAX_BPF_REG; i++)
- mark_map_reg(regs, i, id, is_null);
+ mark_ptr_or_null_reg(®s[i], id, is_null);
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
- mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null);
+ mark_ptr_or_null_reg(reg, id, is_null);
}
}
}
@@ -3851,12 +3856,14 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
/* detect if R == 0 where R is returned from bpf_map_lookup_elem() */
if (BPF_SRC(insn->code) == BPF_K &&
insn->imm == 0 && (opcode == BPF_JEQ || opcode == BPF_JNE) &&
- dst_reg->type == PTR_TO_MAP_VALUE_OR_NULL) {
- /* Mark all identical map registers in each branch as either
+ reg_type_may_be_null(dst_reg->type)) {
+ /* Mark all identical registers in each branch as either
* safe or unknown depending R == 0 or R != 0 conditional.
*/
- mark_map_regs(this_branch, insn->dst_reg, opcode == BPF_JNE);
- mark_map_regs(other_branch, insn->dst_reg, opcode == BPF_JEQ);
+ mark_ptr_or_null_regs(this_branch, insn->dst_reg,
+ opcode == BPF_JNE);
+ mark_ptr_or_null_regs(other_branch, insn->dst_reg,
+ opcode == BPF_JEQ);
} else if (!try_match_pkt_pointers(insn, dst_reg, ®s[insn->src_reg],
this_branch, other_branch) &&
is_pointer_value(env, insn->dst_reg)) {
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 04/11] bpf: Add PTR_TO_SOCKET verifier type
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Teach the verifier a little bit about a new type of pointer, a
PTR_TO_SOCKET. This pointer type is accessed from BPF through the
'struct bpf_sock' structure.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
---
v2: Reuse reg_type_mismatch() in more places
Reduce the number of passes at convert_ctx_access()
---
include/linux/bpf.h | 17 +++++
include/linux/bpf_verifier.h | 2 +
kernel/bpf/verifier.c | 120 +++++++++++++++++++++++++++++++----
net/core/filter.c | 30 +++++----
4 files changed, 143 insertions(+), 26 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 988a00797bcd..daeb0d343d9c 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -154,6 +154,7 @@ enum bpf_arg_type {
ARG_PTR_TO_CTX, /* pointer to context */
ARG_ANYTHING, /* any (initialized) argument is ok */
+ ARG_PTR_TO_SOCKET, /* pointer to bpf_sock */
};
/* type of values returned from helper functions */
@@ -162,6 +163,7 @@ enum bpf_return_type {
RET_VOID, /* function doesn't return anything */
RET_PTR_TO_MAP_VALUE, /* returns a pointer to map elem value */
RET_PTR_TO_MAP_VALUE_OR_NULL, /* returns a pointer to map elem value or NULL */
+ RET_PTR_TO_SOCKET_OR_NULL, /* returns a pointer to a socket or NULL */
};
/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
@@ -213,6 +215,8 @@ enum bpf_reg_type {
PTR_TO_PACKET, /* reg points to skb->data */
PTR_TO_PACKET_END, /* skb->data + headlen */
PTR_TO_FLOW_KEYS, /* reg points to bpf_flow_keys */
+ PTR_TO_SOCKET, /* reg points to struct bpf_sock */
+ PTR_TO_SOCKET_OR_NULL, /* reg points to struct bpf_sock or NULL */
};
/* The information passed from prog-specific *_is_valid_access
@@ -335,6 +339,11 @@ const struct bpf_func_proto *bpf_get_trace_printk_proto(void);
typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src,
unsigned long off, unsigned long len);
+typedef u32 (*bpf_convert_ctx_access_t)(enum bpf_access_type type,
+ const struct bpf_insn *src,
+ struct bpf_insn *dst,
+ struct bpf_prog *prog,
+ u32 *target_size);
u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy);
@@ -828,4 +837,12 @@ extern const struct bpf_func_proto bpf_get_local_storage_proto;
void bpf_user_rnd_init_once(void);
u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
+bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
+ struct bpf_insn_access_aux *info);
+u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
+ const struct bpf_insn *si,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog,
+ u32 *target_size);
+
#endif /* _LINUX_BPF_H */
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index af262b97f586..23a2b17bfd75 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -58,6 +58,8 @@ struct bpf_reg_state {
* offset, so they can share range knowledge.
* For PTR_TO_MAP_VALUE_OR_NULL this is used to share which map value we
* came from, when one is tested for != NULL.
+ * For PTR_TO_SOCKET this is used to share which pointers retain the
+ * same reference to the socket, to determine proper reference freeing.
*/
u32 id;
/* For scalar types (SCALAR_VALUE), this represents our knowledge of
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 7dccb18ede03..1fee63d82290 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -80,8 +80,8 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = {
* (like pointer plus pointer becomes SCALAR_VALUE type)
*
* When verifier sees load or store instructions the type of base register
- * can be: PTR_TO_MAP_VALUE, PTR_TO_CTX, PTR_TO_STACK. These are three pointer
- * types recognized by check_mem_access() function.
+ * can be: PTR_TO_MAP_VALUE, PTR_TO_CTX, PTR_TO_STACK, PTR_TO_SOCKET. These are
+ * four pointer types recognized by check_mem_access() function.
*
* PTR_TO_MAP_VALUE means that this register is pointing to 'map element value'
* and the range of [ptr, ptr + map's value_size) is accessible.
@@ -267,6 +267,8 @@ static const char * const reg_type_str[] = {
[PTR_TO_PACKET_META] = "pkt_meta",
[PTR_TO_PACKET_END] = "pkt_end",
[PTR_TO_FLOW_KEYS] = "flow_keys",
+ [PTR_TO_SOCKET] = "sock",
+ [PTR_TO_SOCKET_OR_NULL] = "sock_or_null",
};
static char slot_type_char[] = {
@@ -973,6 +975,8 @@ static bool is_spillable_regtype(enum bpf_reg_type type)
case PTR_TO_PACKET_END:
case PTR_TO_FLOW_KEYS:
case CONST_PTR_TO_MAP:
+ case PTR_TO_SOCKET:
+ case PTR_TO_SOCKET_OR_NULL:
return true;
default:
return false;
@@ -1341,6 +1345,28 @@ static int check_flow_keys_access(struct bpf_verifier_env *env, int off,
return 0;
}
+static int check_sock_access(struct bpf_verifier_env *env, u32 regno, int off,
+ int size, enum bpf_access_type t)
+{
+ struct bpf_reg_state *regs = cur_regs(env);
+ struct bpf_reg_state *reg = ®s[regno];
+ struct bpf_insn_access_aux info;
+
+ if (reg->smin_value < 0) {
+ verbose(env, "R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n",
+ regno);
+ return -EACCES;
+ }
+
+ if (!bpf_sock_is_valid_access(off, size, t, &info)) {
+ verbose(env, "invalid bpf_sock_ops access off=%d size=%d\n",
+ off, size);
+ return -EACCES;
+ }
+
+ return 0;
+}
+
static bool __is_pointer_value(bool allow_ptr_leaks,
const struct bpf_reg_state *reg)
{
@@ -1459,6 +1485,9 @@ static int check_ptr_alignment(struct bpf_verifier_env *env,
*/
strict = true;
break;
+ case PTR_TO_SOCKET:
+ pointer_desc = "sock ";
+ break;
default:
break;
}
@@ -1726,6 +1755,14 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
err = check_flow_keys_access(env, off, size);
if (!err && t == BPF_READ && value_regno >= 0)
mark_reg_unknown(env, regs, value_regno);
+ } else if (reg->type == PTR_TO_SOCKET) {
+ if (t == BPF_WRITE) {
+ verbose(env, "cannot write into socket\n");
+ return -EACCES;
+ }
+ err = check_sock_access(env, regno, off, size, t);
+ if (!err && value_regno >= 0)
+ mark_reg_unknown(env, regs, value_regno);
} else {
verbose(env, "R%d invalid mem access '%s'\n", regno,
reg_type_str[reg->type]);
@@ -1949,6 +1986,10 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
err = check_ctx_reg(env, reg, regno);
if (err < 0)
return err;
+ } else if (arg_type == ARG_PTR_TO_SOCKET) {
+ expected_type = PTR_TO_SOCKET;
+ if (type != expected_type)
+ goto err_type;
} else if (arg_type_is_mem_ptr(arg_type)) {
expected_type = PTR_TO_STACK;
/* One exception here. In case function allows for NULL to be
@@ -2542,6 +2583,10 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
}
regs[BPF_REG_0].map_ptr = meta.map_ptr;
regs[BPF_REG_0].id = ++env->id_gen;
+ } else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
+ mark_reg_known_zero(env, regs, BPF_REG_0);
+ regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL;
+ regs[BPF_REG_0].id = ++env->id_gen;
} else {
verbose(env, "unknown return type %d of func %s#%d\n",
fn->ret_type, func_id_name(func_id), func_id);
@@ -2679,6 +2724,8 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
return -EACCES;
case CONST_PTR_TO_MAP:
case PTR_TO_PACKET_END:
+ case PTR_TO_SOCKET:
+ case PTR_TO_SOCKET_OR_NULL:
verbose(env, "R%d pointer arithmetic on %s prohibited\n",
dst, reg_type_str[ptr_reg->type]);
return -EACCES;
@@ -3626,6 +3673,8 @@ static void mark_ptr_or_null_reg(struct bpf_reg_state *reg, u32 id,
} else {
reg->type = PTR_TO_MAP_VALUE;
}
+ } else if (reg->type == PTR_TO_SOCKET_OR_NULL) {
+ reg->type = PTR_TO_SOCKET;
}
/* We don't need id from this point onwards anymore, thus we
* should better reset it, so that state pruning has chances
@@ -4401,6 +4450,8 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
case CONST_PTR_TO_MAP:
case PTR_TO_PACKET_END:
case PTR_TO_FLOW_KEYS:
+ case PTR_TO_SOCKET:
+ case PTR_TO_SOCKET_OR_NULL:
/* Only valid matches are exact, which memcmp() above
* would have accepted
*/
@@ -4678,6 +4729,37 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
return 0;
}
+/* Return true if it's OK to have the same insn return a different type. */
+static bool reg_type_mismatch_ok(enum bpf_reg_type type)
+{
+ switch (type) {
+ case PTR_TO_CTX:
+ case PTR_TO_SOCKET:
+ case PTR_TO_SOCKET_OR_NULL:
+ return false;
+ default:
+ return true;
+ }
+}
+
+/* If an instruction was previously used with particular pointer types, then we
+ * need to be careful to avoid cases such as the below, where it may be ok
+ * for one branch accessing the pointer, but not ok for the other branch:
+ *
+ * R1 = sock_ptr
+ * goto X;
+ * ...
+ * R1 = some_other_valid_ptr;
+ * goto X;
+ * ...
+ * R2 = *(u32 *)(R1 + 0);
+ */
+static bool reg_type_mismatch(enum bpf_reg_type src, enum bpf_reg_type prev)
+{
+ return src != prev && (!reg_type_mismatch_ok(src) ||
+ !reg_type_mismatch_ok(prev));
+}
+
static int do_check(struct bpf_verifier_env *env)
{
struct bpf_verifier_state *state;
@@ -4810,9 +4892,7 @@ static int do_check(struct bpf_verifier_env *env)
*/
*prev_src_type = src_reg_type;
- } else if (src_reg_type != *prev_src_type &&
- (src_reg_type == PTR_TO_CTX ||
- *prev_src_type == PTR_TO_CTX)) {
+ } else if (reg_type_mismatch(src_reg_type, *prev_src_type)) {
/* ABuser program is trying to use the same insn
* dst_reg = *(u32*) (src_reg + off)
* with different pointer types:
@@ -4857,9 +4937,7 @@ static int do_check(struct bpf_verifier_env *env)
if (*prev_dst_type == NOT_INIT) {
*prev_dst_type = dst_reg_type;
- } else if (dst_reg_type != *prev_dst_type &&
- (dst_reg_type == PTR_TO_CTX ||
- *prev_dst_type == PTR_TO_CTX)) {
+ } else if (reg_type_mismatch(dst_reg_type, *prev_dst_type)) {
verbose(env, "same insn cannot be used with different pointers\n");
return -EINVAL;
}
@@ -5276,8 +5354,10 @@ static void sanitize_dead_code(struct bpf_verifier_env *env)
}
}
-/* convert load instructions that access fields of 'struct __sk_buff'
- * into sequence of instructions that access fields of 'struct sk_buff'
+/* convert load instructions that access fields of a context type into a
+ * sequence of instructions that access fields of the underlying structure:
+ * struct __sk_buff -> struct sk_buff
+ * struct bpf_sock_ops -> struct sock
*/
static int convert_ctx_accesses(struct bpf_verifier_env *env)
{
@@ -5306,12 +5386,14 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
}
}
- if (!ops->convert_ctx_access || bpf_prog_is_dev_bound(env->prog->aux))
+ if (bpf_prog_is_dev_bound(env->prog->aux))
return 0;
insn = env->prog->insnsi + delta;
for (i = 0; i < insn_cnt; i++, insn++) {
+ bpf_convert_ctx_access_t convert_ctx_access;
+
if (insn->code == (BPF_LDX | BPF_MEM | BPF_B) ||
insn->code == (BPF_LDX | BPF_MEM | BPF_H) ||
insn->code == (BPF_LDX | BPF_MEM | BPF_W) ||
@@ -5353,8 +5435,18 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
continue;
}
- if (env->insn_aux_data[i + delta].ptr_type != PTR_TO_CTX)
+ switch (env->insn_aux_data[i + delta].ptr_type) {
+ case PTR_TO_CTX:
+ if (!ops->convert_ctx_access)
+ continue;
+ convert_ctx_access = ops->convert_ctx_access;
+ break;
+ case PTR_TO_SOCKET:
+ convert_ctx_access = bpf_sock_convert_ctx_access;
+ break;
+ default:
continue;
+ }
ctx_field_size = env->insn_aux_data[i + delta].ctx_field_size;
size = BPF_LDST_BYTES(insn);
@@ -5386,8 +5478,8 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
}
target_size = 0;
- cnt = ops->convert_ctx_access(type, insn, insn_buf, env->prog,
- &target_size);
+ cnt = convert_ctx_access(type, insn, insn_buf, env->prog,
+ &target_size);
if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf) ||
(ctx_field_size && !target_size)) {
verbose(env, "bpf verifier is misconfigured\n");
diff --git a/net/core/filter.c b/net/core/filter.c
index 9cc76f134ddb..43f81883f31d 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5393,23 +5393,29 @@ static bool __sock_filter_check_size(int off, int size,
return size == size_default;
}
-static bool sock_filter_is_valid_access(int off, int size,
- enum bpf_access_type type,
- const struct bpf_prog *prog,
- struct bpf_insn_access_aux *info)
+bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
+ struct bpf_insn_access_aux *info)
{
if (off < 0 || off >= sizeof(struct bpf_sock))
return false;
if (off % size != 0)
return false;
- if (!__sock_filter_check_attach_type(off, type,
- prog->expected_attach_type))
- return false;
if (!__sock_filter_check_size(off, size, info))
return false;
return true;
}
+static bool sock_filter_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (!__sock_filter_check_attach_type(off, type,
+ prog->expected_attach_type))
+ return false;
+ return bpf_sock_is_valid_access(off, size, type, info);
+}
+
static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog, int drop_verdict)
{
@@ -6121,10 +6127,10 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type,
return insn - insn_buf;
}
-static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
- const struct bpf_insn *si,
- struct bpf_insn *insn_buf,
- struct bpf_prog *prog, u32 *target_size)
+u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
+ const struct bpf_insn *si,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
@@ -7036,7 +7042,7 @@ const struct bpf_prog_ops lwt_seg6local_prog_ops = {
const struct bpf_verifier_ops cg_sock_verifier_ops = {
.get_func_proto = sock_filter_func_proto,
.is_valid_access = sock_filter_is_valid_access,
- .convert_ctx_access = sock_filter_convert_ctx_access,
+ .convert_ctx_access = bpf_sock_convert_ctx_access,
};
const struct bpf_prog_ops cg_sock_prog_ops = {
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 05/11] bpf: Macrofy stack state copy
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
An upcoming commit will need very similar copy/realloc boilerplate, so
refactor the existing stack copy/realloc functions into macros to
simplify it.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
kernel/bpf/verifier.c | 106 ++++++++++++++++++++++++------------------
1 file changed, 60 insertions(+), 46 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1fee63d82290..311340360aa3 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -388,60 +388,74 @@ static void print_verifier_state(struct bpf_verifier_env *env,
verbose(env, "\n");
}
-static int copy_stack_state(struct bpf_func_state *dst,
- const struct bpf_func_state *src)
-{
- if (!src->stack)
- return 0;
- if (WARN_ON_ONCE(dst->allocated_stack < src->allocated_stack)) {
- /* internal bug, make state invalid to reject the program */
- memset(dst, 0, sizeof(*dst));
- return -EFAULT;
- }
- memcpy(dst->stack, src->stack,
- sizeof(*src->stack) * (src->allocated_stack / BPF_REG_SIZE));
- return 0;
-}
+#define COPY_STATE_FN(NAME, COUNT, FIELD, SIZE) \
+static int copy_##NAME##_state(struct bpf_func_state *dst, \
+ const struct bpf_func_state *src) \
+{ \
+ if (!src->FIELD) \
+ return 0; \
+ if (WARN_ON_ONCE(dst->COUNT < src->COUNT)) { \
+ /* internal bug, make state invalid to reject the program */ \
+ memset(dst, 0, sizeof(*dst)); \
+ return -EFAULT; \
+ } \
+ memcpy(dst->FIELD, src->FIELD, \
+ sizeof(*src->FIELD) * (src->COUNT / SIZE)); \
+ return 0; \
+}
+/* copy_stack_state() */
+COPY_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE)
+#undef COPY_STATE_FN
+
+#define REALLOC_STATE_FN(NAME, COUNT, FIELD, SIZE) \
+static int realloc_##NAME##_state(struct bpf_func_state *state, int size, \
+ bool copy_old) \
+{ \
+ u32 old_size = state->COUNT; \
+ struct bpf_##NAME##_state *new_##FIELD; \
+ int slot = size / SIZE; \
+ \
+ if (size <= old_size || !size) { \
+ if (copy_old) \
+ return 0; \
+ state->COUNT = slot * SIZE; \
+ if (!size && old_size) { \
+ kfree(state->FIELD); \
+ state->FIELD = NULL; \
+ } \
+ return 0; \
+ } \
+ new_##FIELD = kmalloc_array(slot, sizeof(struct bpf_##NAME##_state), \
+ GFP_KERNEL); \
+ if (!new_##FIELD) \
+ return -ENOMEM; \
+ if (copy_old) { \
+ if (state->FIELD) \
+ memcpy(new_##FIELD, state->FIELD, \
+ sizeof(*new_##FIELD) * (old_size / SIZE)); \
+ memset(new_##FIELD + old_size / SIZE, 0, \
+ sizeof(*new_##FIELD) * (size - old_size) / SIZE); \
+ } \
+ state->COUNT = slot * SIZE; \
+ kfree(state->FIELD); \
+ state->FIELD = new_##FIELD; \
+ return 0; \
+}
+/* realloc_stack_state() */
+REALLOC_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE)
+#undef REALLOC_STATE_FN
/* do_check() starts with zero-sized stack in struct bpf_verifier_state to
* make it consume minimal amount of memory. check_stack_write() access from
* the program calls into realloc_func_state() to grow the stack size.
- * Note there is a non-zero parent pointer inside each reg of bpf_verifier_state
- * which this function copies over. It points to corresponding reg in previous
- * bpf_verifier_state which is never reallocated
+ * Note there is a non-zero 'parent' pointer inside bpf_verifier_state
+ * which realloc_stack_state() copies over. It points to previous
+ * bpf_verifier_state which is never reallocated.
*/
static int realloc_func_state(struct bpf_func_state *state, int size,
bool copy_old)
{
- u32 old_size = state->allocated_stack;
- struct bpf_stack_state *new_stack;
- int slot = size / BPF_REG_SIZE;
-
- if (size <= old_size || !size) {
- if (copy_old)
- return 0;
- state->allocated_stack = slot * BPF_REG_SIZE;
- if (!size && old_size) {
- kfree(state->stack);
- state->stack = NULL;
- }
- return 0;
- }
- new_stack = kmalloc_array(slot, sizeof(struct bpf_stack_state),
- GFP_KERNEL);
- if (!new_stack)
- return -ENOMEM;
- if (copy_old) {
- if (state->stack)
- memcpy(new_stack, state->stack,
- sizeof(*new_stack) * (old_size / BPF_REG_SIZE));
- memset(new_stack + old_size / BPF_REG_SIZE, 0,
- sizeof(*new_stack) * (size - old_size) / BPF_REG_SIZE);
- }
- state->allocated_stack = slot * BPF_REG_SIZE;
- kfree(state->stack);
- state->stack = new_stack;
- return 0;
+ return realloc_stack_state(state, size, copy_old);
}
static void free_func_state(struct bpf_func_state *state)
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 06/11] bpf: Add reference tracking to verifier
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Allow helper functions to acquire a reference and return it into a
register. Specific pointer types such as the PTR_TO_SOCKET will
implicitly represent such a reference. The verifier must ensure that
these references are released exactly once in each path through the
program.
To achieve this, this commit assigns an id to the pointer and tracks it
in the 'bpf_func_state', then when the function or program exits,
verifies that all of the acquired references have been freed. When the
pointer is passed to a function that frees the reference, it is removed
from the 'bpf_func_state` and all existing copies of the pointer in
registers are marked invalid.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
v2: Replace ptr_id defensive coding when releasing reference state with an
internal error (-EFAULT)
---
include/linux/bpf_verifier.h | 24 ++-
kernel/bpf/verifier.c | 303 ++++++++++++++++++++++++++++++++---
2 files changed, 306 insertions(+), 21 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 23a2b17bfd75..23f222e0cb0b 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -104,6 +104,17 @@ struct bpf_stack_state {
u8 slot_type[BPF_REG_SIZE];
};
+struct bpf_reference_state {
+ /* Track each reference created with a unique id, even if the same
+ * instruction creates the reference multiple times (eg, via CALL).
+ */
+ int id;
+ /* Instruction where the allocation of this reference occurred. This
+ * is used purely to inform the user of a reference leak.
+ */
+ int insn_idx;
+};
+
/* state of the program:
* type of all registers and stack info
*/
@@ -121,7 +132,9 @@ struct bpf_func_state {
*/
u32 subprogno;
- /* should be second to last. See copy_func_state() */
+ /* The following fields should be last. See copy_func_state() */
+ int acquired_refs;
+ struct bpf_reference_state *refs;
int allocated_stack;
struct bpf_stack_state *stack;
};
@@ -217,11 +230,16 @@ __printf(2, 0) void bpf_verifier_vlog(struct bpf_verifier_log *log,
__printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
const char *fmt, ...);
-static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
+static inline struct bpf_func_state *cur_func(struct bpf_verifier_env *env)
{
struct bpf_verifier_state *cur = env->cur_state;
- return cur->frame[cur->curframe]->regs;
+ return cur->frame[cur->curframe];
+}
+
+static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
+{
+ return cur_func(env)->regs;
}
int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 311340360aa3..16818508b225 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1,5 +1,6 @@
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
* Copyright (c) 2016 Facebook
+ * Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
@@ -140,6 +141,18 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = {
*
* After the call R0 is set to return type of the function and registers R1-R5
* are set to NOT_INIT to indicate that they are no longer readable.
+ *
+ * The following reference types represent a potential reference to a kernel
+ * resource which, after first being allocated, must be checked and freed by
+ * the BPF program:
+ * - PTR_TO_SOCKET_OR_NULL, PTR_TO_SOCKET
+ *
+ * When the verifier sees a helper call return a reference type, it allocates a
+ * pointer id for the reference and stores it in the current function state.
+ * Similar to the way that PTR_TO_MAP_VALUE_OR_NULL is converted into
+ * PTR_TO_MAP_VALUE, PTR_TO_SOCKET_OR_NULL becomes PTR_TO_SOCKET when the type
+ * passes through a NULL-check conditional. For the branch wherein the state is
+ * changed to CONST_IMM, the verifier releases the reference.
*/
/* verifier_state + insn_idx are pushed to stack when branch is encountered */
@@ -189,6 +202,7 @@ struct bpf_call_arg_meta {
int access_size;
s64 msize_smax_value;
u64 msize_umax_value;
+ int ptr_id;
};
static DEFINE_MUTEX(bpf_verifier_lock);
@@ -251,7 +265,42 @@ static bool type_is_pkt_pointer(enum bpf_reg_type type)
static bool reg_type_may_be_null(enum bpf_reg_type type)
{
- return type == PTR_TO_MAP_VALUE_OR_NULL;
+ return type == PTR_TO_MAP_VALUE_OR_NULL ||
+ type == PTR_TO_SOCKET_OR_NULL;
+}
+
+static bool type_is_refcounted(enum bpf_reg_type type)
+{
+ return type == PTR_TO_SOCKET;
+}
+
+static bool type_is_refcounted_or_null(enum bpf_reg_type type)
+{
+ return type == PTR_TO_SOCKET || type == PTR_TO_SOCKET_OR_NULL;
+}
+
+static bool reg_is_refcounted(const struct bpf_reg_state *reg)
+{
+ return type_is_refcounted(reg->type);
+}
+
+static bool reg_is_refcounted_or_null(const struct bpf_reg_state *reg)
+{
+ return type_is_refcounted_or_null(reg->type);
+}
+
+static bool arg_type_is_refcounted(enum bpf_arg_type type)
+{
+ return type == ARG_PTR_TO_SOCKET;
+}
+
+/* Determine whether the function releases some resources allocated by another
+ * function call. The first reference type argument will be assumed to be
+ * released by release_reference().
+ */
+static bool is_release_function(enum bpf_func_id func_id)
+{
+ return false;
}
/* string representation of 'enum bpf_reg_type' */
@@ -385,6 +434,12 @@ static void print_verifier_state(struct bpf_verifier_env *env,
else
verbose(env, "=%s", types_buf);
}
+ if (state->acquired_refs && state->refs[0].id) {
+ verbose(env, " refs=%d", state->refs[0].id);
+ for (i = 1; i < state->acquired_refs; i++)
+ if (state->refs[i].id)
+ verbose(env, ",%d", state->refs[i].id);
+ }
verbose(env, "\n");
}
@@ -403,6 +458,8 @@ static int copy_##NAME##_state(struct bpf_func_state *dst, \
sizeof(*src->FIELD) * (src->COUNT / SIZE)); \
return 0; \
}
+/* copy_reference_state() */
+COPY_STATE_FN(reference, acquired_refs, refs, 1)
/* copy_stack_state() */
COPY_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE)
#undef COPY_STATE_FN
@@ -441,6 +498,8 @@ static int realloc_##NAME##_state(struct bpf_func_state *state, int size, \
state->FIELD = new_##FIELD; \
return 0; \
}
+/* realloc_reference_state() */
+REALLOC_STATE_FN(reference, acquired_refs, refs, 1)
/* realloc_stack_state() */
REALLOC_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE)
#undef REALLOC_STATE_FN
@@ -452,16 +511,89 @@ REALLOC_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE)
* which realloc_stack_state() copies over. It points to previous
* bpf_verifier_state which is never reallocated.
*/
-static int realloc_func_state(struct bpf_func_state *state, int size,
- bool copy_old)
+static int realloc_func_state(struct bpf_func_state *state, int stack_size,
+ int refs_size, bool copy_old)
{
- return realloc_stack_state(state, size, copy_old);
+ int err = realloc_reference_state(state, refs_size, copy_old);
+ if (err)
+ return err;
+ return realloc_stack_state(state, stack_size, copy_old);
+}
+
+/* Acquire a pointer id from the env and update the state->refs to include
+ * this new pointer reference.
+ * On success, returns a valid pointer id to associate with the register
+ * On failure, returns a negative errno.
+ */
+static int acquire_reference_state(struct bpf_verifier_env *env, int insn_idx)
+{
+ struct bpf_func_state *state = cur_func(env);
+ int new_ofs = state->acquired_refs;
+ int id, err;
+
+ err = realloc_reference_state(state, state->acquired_refs + 1, true);
+ if (err)
+ return err;
+ id = ++env->id_gen;
+ state->refs[new_ofs].id = id;
+ state->refs[new_ofs].insn_idx = insn_idx;
+
+ return id;
+}
+
+/* release function corresponding to acquire_reference_state(). Idempotent. */
+static int __release_reference_state(struct bpf_func_state *state, int ptr_id)
+{
+ int i, last_idx;
+
+ if (!ptr_id)
+ return -EFAULT;
+
+ last_idx = state->acquired_refs - 1;
+ for (i = 0; i < state->acquired_refs; i++) {
+ if (state->refs[i].id == ptr_id) {
+ if (last_idx && i != last_idx)
+ memcpy(&state->refs[i], &state->refs[last_idx],
+ sizeof(*state->refs));
+ memset(&state->refs[last_idx], 0, sizeof(*state->refs));
+ state->acquired_refs--;
+ return 0;
+ }
+ }
+ return -EFAULT;
+}
+
+/* variation on the above for cases where we expect that there must be an
+ * outstanding reference for the specified ptr_id.
+ */
+static int release_reference_state(struct bpf_verifier_env *env, int ptr_id)
+{
+ struct bpf_func_state *state = cur_func(env);
+ int err;
+
+ err = __release_reference_state(state, ptr_id);
+ if (WARN_ON_ONCE(err != 0))
+ verbose(env, "verifier internal error: can't release reference\n");
+ return err;
+}
+
+static int transfer_reference_state(struct bpf_func_state *dst,
+ struct bpf_func_state *src)
+{
+ int err = realloc_reference_state(dst, src->acquired_refs, false);
+ if (err)
+ return err;
+ err = copy_reference_state(dst, src);
+ if (err)
+ return err;
+ return 0;
}
static void free_func_state(struct bpf_func_state *state)
{
if (!state)
return;
+ kfree(state->refs);
kfree(state->stack);
kfree(state);
}
@@ -487,10 +619,14 @@ static int copy_func_state(struct bpf_func_state *dst,
{
int err;
- err = realloc_func_state(dst, src->allocated_stack, false);
+ err = realloc_func_state(dst, src->allocated_stack, src->acquired_refs,
+ false);
+ if (err)
+ return err;
+ memcpy(dst, src, offsetof(struct bpf_func_state, acquired_refs));
+ err = copy_reference_state(dst, src);
if (err)
return err;
- memcpy(dst, src, offsetof(struct bpf_func_state, allocated_stack));
return copy_stack_state(dst, src);
}
@@ -1015,7 +1151,7 @@ static int check_stack_write(struct bpf_verifier_env *env,
enum bpf_reg_type type;
err = realloc_func_state(state, round_up(slot + 1, BPF_REG_SIZE),
- true);
+ state->acquired_refs, true);
if (err)
return err;
/* caller checked that off % size == 0 and -MAX_BPF_STACK <= off < 0,
@@ -2004,6 +2140,12 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
expected_type = PTR_TO_SOCKET;
if (type != expected_type)
goto err_type;
+ if (meta->ptr_id || !reg->id) {
+ verbose(env, "verifier internal error: mismatched references meta=%d, reg=%d\n",
+ meta->ptr_id, reg->id);
+ return -EFAULT;
+ }
+ meta->ptr_id = reg->id;
} else if (arg_type_is_mem_ptr(arg_type)) {
expected_type = PTR_TO_STACK;
/* One exception here. In case function allows for NULL to be
@@ -2291,10 +2433,32 @@ static bool check_arg_pair_ok(const struct bpf_func_proto *fn)
return true;
}
+static bool check_refcount_ok(const struct bpf_func_proto *fn)
+{
+ int count = 0;
+
+ if (arg_type_is_refcounted(fn->arg1_type))
+ count++;
+ if (arg_type_is_refcounted(fn->arg2_type))
+ count++;
+ if (arg_type_is_refcounted(fn->arg3_type))
+ count++;
+ if (arg_type_is_refcounted(fn->arg4_type))
+ count++;
+ if (arg_type_is_refcounted(fn->arg5_type))
+ count++;
+
+ /* We only support one arg being unreferenced at the moment,
+ * which is sufficient for the helper functions we have right now.
+ */
+ return count <= 1;
+}
+
static int check_func_proto(const struct bpf_func_proto *fn)
{
return check_raw_mode_ok(fn) &&
- check_arg_pair_ok(fn) ? 0 : -EINVAL;
+ check_arg_pair_ok(fn) &&
+ check_refcount_ok(fn) ? 0 : -EINVAL;
}
/* Packet data might have moved, any old PTR_TO_PACKET[_META,_END]
@@ -2327,12 +2491,45 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
__clear_all_pkt_pointers(env, vstate->frame[i]);
}
+static void release_reg_references(struct bpf_verifier_env *env,
+ struct bpf_func_state *state, int id)
+{
+ struct bpf_reg_state *regs = state->regs, *reg;
+ int i;
+
+ for (i = 0; i < MAX_BPF_REG; i++)
+ if (regs[i].id == id)
+ mark_reg_unknown(env, regs, i);
+
+ for_each_spilled_reg(i, state, reg) {
+ if (!reg)
+ continue;
+ if (reg_is_refcounted(reg) && reg->id == id)
+ __mark_reg_unknown(reg);
+ }
+}
+
+/* The pointer with the specified id has released its reference to kernel
+ * resources. Identify all copies of the same pointer and clear the reference.
+ */
+static int release_reference(struct bpf_verifier_env *env,
+ struct bpf_call_arg_meta *meta)
+{
+ struct bpf_verifier_state *vstate = env->cur_state;
+ int i;
+
+ for (i = 0; i <= vstate->curframe; i++)
+ release_reg_references(env, vstate->frame[i], meta->ptr_id);
+
+ return release_reference_state(env, meta->ptr_id);
+}
+
static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
int *insn_idx)
{
struct bpf_verifier_state *state = env->cur_state;
struct bpf_func_state *caller, *callee;
- int i, subprog, target_insn;
+ int i, err, subprog, target_insn;
if (state->curframe + 1 >= MAX_CALL_FRAMES) {
verbose(env, "the call stack of %d frames is too deep\n",
@@ -2370,6 +2567,11 @@ static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
state->curframe + 1 /* frameno within this callchain */,
subprog /* subprog number within this prog */);
+ /* Transfer references to the callee */
+ err = transfer_reference_state(callee, caller);
+ if (err)
+ return err;
+
/* copy r1 - r5 args that callee can access. The copy includes parent
* pointers, which connects us up to the liveness chain
*/
@@ -2402,6 +2604,7 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
struct bpf_verifier_state *state = env->cur_state;
struct bpf_func_state *caller, *callee;
struct bpf_reg_state *r0;
+ int err;
callee = state->frame[state->curframe];
r0 = &callee->regs[BPF_REG_0];
@@ -2421,6 +2624,11 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
/* return to the caller whatever r0 had in the callee */
caller->regs[BPF_REG_0] = *r0;
+ /* Transfer references to the caller */
+ err = transfer_reference_state(caller, callee);
+ if (err)
+ return err;
+
*insn_idx = callee->callsite + 1;
if (env->log.level) {
verbose(env, "returning from callee:\n");
@@ -2477,6 +2685,18 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
return 0;
}
+static int check_reference_leak(struct bpf_verifier_env *env)
+{
+ struct bpf_func_state *state = cur_func(env);
+ int i;
+
+ for (i = 0; i < state->acquired_refs; i++) {
+ verbose(env, "Unreleased reference id=%d alloc_insn=%d\n",
+ state->refs[i].id, state->refs[i].insn_idx);
+ }
+ return state->acquired_refs ? -EINVAL : 0;
+}
+
static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
{
const struct bpf_func_proto *fn = NULL;
@@ -2555,6 +2775,18 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
return err;
}
+ if (func_id == BPF_FUNC_tail_call) {
+ err = check_reference_leak(env);
+ if (err) {
+ verbose(env, "tail_call would lead to reference leak\n");
+ return err;
+ }
+ } else if (is_release_function(func_id)) {
+ err = release_reference(env, &meta);
+ if (err)
+ return err;
+ }
+
regs = cur_regs(env);
/* check that flags argument in get_local_storage(map, flags) is 0,
@@ -2598,9 +2830,12 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
regs[BPF_REG_0].map_ptr = meta.map_ptr;
regs[BPF_REG_0].id = ++env->id_gen;
} else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
+ int id = acquire_reference_state(env, insn_idx);
+ if (id < 0)
+ return id;
mark_reg_known_zero(env, regs, BPF_REG_0);
regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL;
- regs[BPF_REG_0].id = ++env->id_gen;
+ regs[BPF_REG_0].id = id;
} else {
verbose(env, "unknown return type %d of func %s#%d\n",
fn->ret_type, func_id_name(func_id), func_id);
@@ -3664,7 +3899,8 @@ static void reg_combine_min_max(struct bpf_reg_state *true_src,
}
}
-static void mark_ptr_or_null_reg(struct bpf_reg_state *reg, u32 id,
+static void mark_ptr_or_null_reg(struct bpf_func_state *state,
+ struct bpf_reg_state *reg, u32 id,
bool is_null)
{
if (reg_type_may_be_null(reg->type) && reg->id == id) {
@@ -3690,11 +3926,13 @@ static void mark_ptr_or_null_reg(struct bpf_reg_state *reg, u32 id,
} else if (reg->type == PTR_TO_SOCKET_OR_NULL) {
reg->type = PTR_TO_SOCKET;
}
- /* We don't need id from this point onwards anymore, thus we
- * should better reset it, so that state pruning has chances
- * to take effect.
- */
- reg->id = 0;
+ if (is_null || !reg_is_refcounted(reg)) {
+ /* We don't need id from this point onwards anymore,
+ * thus we should better reset it, so that state
+ * pruning has chances to take effect.
+ */
+ reg->id = 0;
+ }
}
}
@@ -3709,15 +3947,18 @@ static void mark_ptr_or_null_regs(struct bpf_verifier_state *vstate, u32 regno,
u32 id = regs[regno].id;
int i, j;
+ if (reg_is_refcounted_or_null(®s[regno]) && is_null)
+ __release_reference_state(state, id);
+
for (i = 0; i < MAX_BPF_REG; i++)
- mark_ptr_or_null_reg(®s[i], id, is_null);
+ mark_ptr_or_null_reg(state, ®s[i], id, is_null);
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
- mark_ptr_or_null_reg(reg, id, is_null);
+ mark_ptr_or_null_reg(state, reg, id, is_null);
}
}
}
@@ -4049,6 +4290,16 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
if (err)
return err;
+ /* Disallow usage of BPF_LD_[ABS|IND] with reference tracking, as
+ * gen_ld_abs() may terminate the program at runtime, leading to
+ * reference leak.
+ */
+ err = check_reference_leak(env);
+ if (err) {
+ verbose(env, "BPF_LD_[ABS|IND] cannot be mixed with socket references\n");
+ return err;
+ }
+
if (regs[BPF_REG_6].type != PTR_TO_CTX) {
verbose(env,
"at the time of BPF_LD_ABS|IND R6 != pointer to skb\n");
@@ -4541,6 +4792,14 @@ static bool stacksafe(struct bpf_func_state *old,
return true;
}
+static bool refsafe(struct bpf_func_state *old, struct bpf_func_state *cur)
+{
+ if (old->acquired_refs != cur->acquired_refs)
+ return false;
+ return !memcmp(old->refs, cur->refs,
+ sizeof(*old->refs) * old->acquired_refs);
+}
+
/* compare two verifier states
*
* all states stored in state_list are known to be valid, since
@@ -4586,6 +4845,9 @@ static bool func_states_equal(struct bpf_func_state *old,
if (!stacksafe(old, cur, idmap))
goto out_free;
+
+ if (!refsafe(old, cur))
+ goto out_free;
ret = true;
out_free:
kfree(idmap);
@@ -4867,6 +5129,7 @@ static int do_check(struct bpf_verifier_env *env)
regs = cur_regs(env);
env->insn_aux_data[insn_idx].seen = true;
+
if (class == BPF_ALU || class == BPF_ALU64) {
err = check_alu_op(env, insn);
if (err)
@@ -5031,6 +5294,10 @@ static int do_check(struct bpf_verifier_env *env)
continue;
}
+ err = check_reference_leak(env);
+ if (err)
+ return err;
+
/* eBPF calling convetion is such that R0 is used
* to return the value from eBPF program.
* Make sure that it's readable at this time
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 07/11] bpf: Add helper to retrieve socket in BPF
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
This patch adds new BPF helper functions, bpf_sk_lookup_tcp() and
bpf_sk_lookup_udp() which allows BPF programs to find out if there is a
socket listening on this host, and returns a socket pointer which the
BPF program can then access to determine, for instance, whether to
forward or drop traffic. bpf_sk_lookup_xxx() may take a reference on the
socket, so when a BPF program makes use of this function, it must
subsequently pass the returned pointer into the newly added sk_release()
to return the reference.
By way of example, the following pseudocode would filter inbound
connections at XDP if there is no corresponding service listening for
the traffic:
struct bpf_sock_tuple tuple;
struct bpf_sock_ops *sk;
populate_tuple(ctx, &tuple); // Extract the 5tuple from the packet
sk = bpf_sk_lookup_tcp(ctx, &tuple, sizeof tuple, netns, 0);
if (!sk) {
// Couldn't find a socket listening for this traffic. Drop.
return TC_ACT_SHOT;
}
bpf_sk_release(sk, 0);
return TC_ACT_OK;
Signed-off-by: Joe Stringer <joe@wand.net.nz>
---
v2: Rework 'struct bpf_sock_tuple' to allow passing a packet pointer
Limit netns_id field to 32 bits
Fix compile error with CONFIG_IPV6 enabled
Allow direct packet access from helper
---
include/uapi/linux/bpf.h | 57 ++++++++-
kernel/bpf/verifier.c | 8 +-
net/core/filter.c | 149 ++++++++++++++++++++++
tools/include/uapi/linux/bpf.h | 57 ++++++++-
tools/testing/selftests/bpf/bpf_helpers.h | 12 ++
5 files changed, 280 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index aa5ccd2385ed..620adbb09a94 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2143,6 +2143,41 @@ union bpf_attr {
* request in the skb.
* Return
* 0 on success, or a negative error in case of failure.
+ *
+ * struct bpf_sock_ops *bpf_sk_lookup_tcp(ctx, tuple, tuple_size, netns, flags)
+ * Decription
+ * Look for TCP socket matching 'tuple'. The return value must
+ * be checked, and if non-NULL, released via bpf_sk_release().
+ * @ctx: pointer to ctx
+ * @tuple: pointer to struct bpf_sock_tuple
+ * @tuple_size: size of the tuple
+ * @netns: network namespace id
+ * @flags: flags value
+ * Return
+ * pointer to socket ops on success, or
+ * NULL in case of failure
+ *
+ * struct bpf_sock_ops *bpf_sk_lookup_udp(ctx, tuple, tuple_size, netns, flags)
+ * Decription
+ * Look for UDP socket matching 'tuple'. The return value must
+ * be checked, and if non-NULL, released via bpf_sk_release().
+ * @ctx: pointer to ctx
+ * @tuple: pointer to struct bpf_sock_tuple
+ * @tuple_size: size of the tuple
+ * @netns: network namespace id
+ * @flags: flags value
+ * Return
+ * pointer to socket ops on success, or
+ * NULL in case of failure
+ *
+ * int bpf_sk_release(sock, flags)
+ * Description
+ * Release the reference held by 'sock'.
+ * @sock: Pointer reference to release. Must be found via
+ * bpf_sk_lookup_xxx().
+ * @flags: flags value
+ * Return
+ * 0 on success, or a negative error in case of failure.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -2228,7 +2263,10 @@ union bpf_attr {
FN(get_current_cgroup_id), \
FN(get_local_storage), \
FN(sk_select_reuseport), \
- FN(skb_ancestor_cgroup_id),
+ FN(skb_ancestor_cgroup_id), \
+ FN(sk_lookup_tcp), \
+ FN(sk_lookup_udp), \
+ FN(sk_release),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
@@ -2398,6 +2436,23 @@ struct bpf_sock {
*/
};
+struct bpf_sock_tuple {
+ union {
+ struct {
+ __be32 saddr;
+ __be32 daddr;
+ __be16 sport;
+ __be16 dport;
+ } ipv4;
+ struct {
+ __be32 saddr[4];
+ __be32 daddr[4];
+ __be16 sport;
+ __be16 dport;
+ } ipv6;
+ };
+};
+
#define XDP_PACKET_HEADROOM 256
/* User return codes for XDP prog type.
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 16818508b225..7b7fa94aba58 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -153,6 +153,12 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = {
* PTR_TO_MAP_VALUE, PTR_TO_SOCKET_OR_NULL becomes PTR_TO_SOCKET when the type
* passes through a NULL-check conditional. For the branch wherein the state is
* changed to CONST_IMM, the verifier releases the reference.
+ *
+ * For each helper function that allocates a reference, such as
+ * bpf_sk_lookup_tcp(), there is a corresponding release function, such as
+ * bpf_sk_release(). When a reference type passes into the release function,
+ * the verifier also releases the reference. If any unchecked or unreleased
+ * reference remains at the end of the program, the verifier rejects it.
*/
/* verifier_state + insn_idx are pushed to stack when branch is encountered */
@@ -300,7 +306,7 @@ static bool arg_type_is_refcounted(enum bpf_arg_type type)
*/
static bool is_release_function(enum bpf_func_id func_id)
{
- return false;
+ return func_id == BPF_FUNC_sk_release;
}
/* string representation of 'enum bpf_reg_type' */
diff --git a/net/core/filter.c b/net/core/filter.c
index 43f81883f31d..f0715e2e7b07 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -58,13 +58,17 @@
#include <net/busy_poll.h>
#include <net/tcp.h>
#include <net/xfrm.h>
+#include <net/udp.h>
#include <linux/bpf_trace.h>
#include <net/xdp_sock.h>
#include <linux/inetdevice.h>
+#include <net/inet_hashtables.h>
+#include <net/inet6_hashtables.h>
#include <net/ip_fib.h>
#include <net/flow.h>
#include <net/arp.h>
#include <net/ipv6.h>
+#include <net/net_namespace.h>
#include <linux/seg6_local.h>
#include <net/seg6.h>
#include <net/seg6_local.h>
@@ -4812,6 +4816,139 @@ static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
};
#endif /* CONFIG_IPV6_SEG6_BPF */
+struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
+ struct sk_buff *skb, u8 family, u8 proto)
+{
+ int dif = skb->dev->ifindex;
+ bool refcounted = false;
+ struct sock *sk = NULL;
+
+ if (family == AF_INET) {
+ __be32 src4 = tuple->ipv4.saddr;
+ __be32 dst4 = tuple->ipv4.daddr;
+ int sdif = inet_sdif(skb);
+
+ if (proto == IPPROTO_TCP)
+ sk = __inet_lookup(net, &tcp_hashinfo, skb, 0,
+ src4, tuple->ipv4.sport,
+ dst4, tuple->ipv4.dport,
+ dif, sdif, &refcounted);
+ else
+ sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
+ dst4, tuple->ipv4.dport,
+ dif, sdif, &udp_table, skb);
+#if IS_ENABLED(CONFIG_IPV6)
+ } else {
+ struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
+ struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
+ int sdif = inet6_sdif(skb);
+
+ if (proto == IPPROTO_TCP)
+ sk = __inet6_lookup(net, &tcp_hashinfo, skb, 0,
+ src6, tuple->ipv6.sport,
+ dst6, tuple->ipv6.dport,
+ dif, sdif, &refcounted);
+ else
+ sk = __udp6_lib_lookup(net, src6, tuple->ipv6.sport,
+ dst6, tuple->ipv6.dport,
+ dif, sdif, &udp_table, skb);
+#endif
+ }
+
+ if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
+ WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
+ sk = NULL;
+ }
+ return sk;
+}
+
+/* bpf_sk_lookup performs the core lookup for different types of sockets,
+ * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
+ * Returns the socket as an 'unsigned long' to simplify the casting in the
+ * callers to satisfy BPF_CALL declarations.
+ */
+static unsigned long
+bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
+ u8 proto, u64 netns_id, u64 flags)
+{
+ struct net *caller_net = dev_net(skb->dev);
+ struct sock *sk = NULL;
+ u8 family = AF_UNSPEC;
+ struct net *net;
+
+ family = len == sizeof(tuple->ipv4) ? AF_INET : AF_INET6;
+ if (unlikely(family == AF_UNSPEC || netns_id > U32_MAX || flags))
+ goto out;
+
+ if (netns_id)
+ net = get_net_ns_by_id(caller_net, netns_id);
+ else
+ net = caller_net;
+ if (unlikely(!net))
+ goto out;
+ sk = sk_lookup(net, tuple, skb, family, proto);
+ put_net(net);
+
+ if (sk)
+ sk = sk_to_full_sk(sk);
+out:
+ return (unsigned long) sk;
+}
+
+BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
+ struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
+{
+ return bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP, netns_id, flags);
+}
+
+static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
+ .func = bpf_sk_lookup_tcp,
+ .gpl_only = false,
+ .pkt_access = true,
+ .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+ .arg4_type = ARG_ANYTHING,
+ .arg5_type = ARG_ANYTHING,
+};
+
+BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
+ struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
+{
+ return bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP, netns_id, flags);
+}
+
+static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
+ .func = bpf_sk_lookup_udp,
+ .gpl_only = false,
+ .pkt_access = true,
+ .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+ .arg4_type = ARG_ANYTHING,
+ .arg5_type = ARG_ANYTHING,
+};
+
+BPF_CALL_2(bpf_sk_release, struct sock *, sk, u64, flags)
+{
+ if (!sock_flag(sk, SOCK_RCU_FREE))
+ sock_gen_put(sk);
+
+ if (unlikely(flags))
+ return -EINVAL;
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_sk_release_proto = {
+ .func = bpf_sk_release,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_SOCKET,
+ .arg2_type = ARG_ANYTHING,
+};
+
bool bpf_helper_changes_pkt_data(void *func)
{
if (func == bpf_skb_vlan_push ||
@@ -5018,6 +5155,12 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
case BPF_FUNC_skb_ancestor_cgroup_id:
return &bpf_skb_ancestor_cgroup_id_proto;
#endif
+ case BPF_FUNC_sk_lookup_tcp:
+ return &bpf_sk_lookup_tcp_proto;
+ case BPF_FUNC_sk_lookup_udp:
+ return &bpf_sk_lookup_udp_proto;
+ case BPF_FUNC_sk_release:
+ return &bpf_sk_release_proto;
default:
return bpf_base_func_proto(func_id);
}
@@ -5118,6 +5261,12 @@ sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_sk_redirect_hash_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
+ case BPF_FUNC_sk_lookup_tcp:
+ return &bpf_sk_lookup_tcp_proto;
+ case BPF_FUNC_sk_lookup_udp:
+ return &bpf_sk_lookup_udp_proto;
+ case BPF_FUNC_sk_release:
+ return &bpf_sk_release_proto;
default:
return bpf_base_func_proto(func_id);
}
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index aa5ccd2385ed..620adbb09a94 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -2143,6 +2143,41 @@ union bpf_attr {
* request in the skb.
* Return
* 0 on success, or a negative error in case of failure.
+ *
+ * struct bpf_sock_ops *bpf_sk_lookup_tcp(ctx, tuple, tuple_size, netns, flags)
+ * Decription
+ * Look for TCP socket matching 'tuple'. The return value must
+ * be checked, and if non-NULL, released via bpf_sk_release().
+ * @ctx: pointer to ctx
+ * @tuple: pointer to struct bpf_sock_tuple
+ * @tuple_size: size of the tuple
+ * @netns: network namespace id
+ * @flags: flags value
+ * Return
+ * pointer to socket ops on success, or
+ * NULL in case of failure
+ *
+ * struct bpf_sock_ops *bpf_sk_lookup_udp(ctx, tuple, tuple_size, netns, flags)
+ * Decription
+ * Look for UDP socket matching 'tuple'. The return value must
+ * be checked, and if non-NULL, released via bpf_sk_release().
+ * @ctx: pointer to ctx
+ * @tuple: pointer to struct bpf_sock_tuple
+ * @tuple_size: size of the tuple
+ * @netns: network namespace id
+ * @flags: flags value
+ * Return
+ * pointer to socket ops on success, or
+ * NULL in case of failure
+ *
+ * int bpf_sk_release(sock, flags)
+ * Description
+ * Release the reference held by 'sock'.
+ * @sock: Pointer reference to release. Must be found via
+ * bpf_sk_lookup_xxx().
+ * @flags: flags value
+ * Return
+ * 0 on success, or a negative error in case of failure.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -2228,7 +2263,10 @@ union bpf_attr {
FN(get_current_cgroup_id), \
FN(get_local_storage), \
FN(sk_select_reuseport), \
- FN(skb_ancestor_cgroup_id),
+ FN(skb_ancestor_cgroup_id), \
+ FN(sk_lookup_tcp), \
+ FN(sk_lookup_udp), \
+ FN(sk_release),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
@@ -2398,6 +2436,23 @@ struct bpf_sock {
*/
};
+struct bpf_sock_tuple {
+ union {
+ struct {
+ __be32 saddr;
+ __be32 daddr;
+ __be16 sport;
+ __be16 dport;
+ } ipv4;
+ struct {
+ __be32 saddr[4];
+ __be32 daddr[4];
+ __be16 sport;
+ __be16 dport;
+ } ipv6;
+ };
+};
+
#define XDP_PACKET_HEADROOM 256
/* User return codes for XDP prog type.
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index e4be7730222d..88ce00c3aa0f 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -143,6 +143,18 @@ static unsigned long long (*bpf_skb_cgroup_id)(void *ctx) =
(void *) BPF_FUNC_skb_cgroup_id;
static unsigned long long (*bpf_skb_ancestor_cgroup_id)(void *ctx, int level) =
(void *) BPF_FUNC_skb_ancestor_cgroup_id;
+static struct bpf_sock *(*bpf_sk_lookup_tcp)(void *ctx,
+ struct bpf_sock_tuple *tuple,
+ int size, unsigned int netns_id,
+ unsigned long long flags) =
+ (void *) BPF_FUNC_sk_lookup_tcp;
+static struct bpf_sock *(*bpf_sk_lookup_udp)(void *ctx,
+ struct bpf_sock_tuple *tuple,
+ int size, unsigned int netns_id,
+ unsigned long long flags) =
+ (void *) BPF_FUNC_sk_lookup_udp;
+static int (*bpf_sk_release)(struct bpf_sock *sk, unsigned long long flags) =
+ (void *) BPF_FUNC_sk_release;
/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 08/11] selftests/bpf: Add tests for reference tracking
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
reference tracking: leak potential reference
reference tracking: leak potential reference on stack
reference tracking: leak potential reference on stack 2
reference tracking: zero potential reference
reference tracking: copy and zero potential references
reference tracking: release reference without check
reference tracking: release reference
reference tracking: release reference twice
reference tracking: release reference twice inside branch
reference tracking: alloc, check, free in one subbranch
reference tracking: alloc, check, free in both subbranches
reference tracking in call: free reference in subprog
reference tracking in call: free reference in subprog and outside
reference tracking in call: alloc & leak reference in subprog
reference tracking in call: alloc in subprog, release outside
reference tracking in call: sk_ptr leak into caller stack
reference tracking in call: sk_ptr spill into caller stack
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
tools/testing/selftests/bpf/test_verifier.c | 359 ++++++++++++++++++++
1 file changed, 359 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index ceb55a9f3da9..eb760ead257a 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -3,6 +3,7 @@
*
* Copyright (c) 2014 PLUMgrid, http://plumgrid.com
* Copyright (c) 2017 Facebook
+ * Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
@@ -177,6 +178,23 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
self->retval = (uint32_t)res;
}
+#define BPF_SK_LOOKUP \
+ /* struct bpf_sock_tuple tuple = {} */ \
+ BPF_MOV64_IMM(BPF_REG_2, 0), \
+ BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -16), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -24), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -32), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -40), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -48), \
+ /* sk = sk_lookup_tcp(ctx, &tuple, sizeof tuple, 0, 0) */ \
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), \
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -48), \
+ BPF_MOV64_IMM(BPF_REG_3, 44), \
+ BPF_MOV64_IMM(BPF_REG_4, 0), \
+ BPF_MOV64_IMM(BPF_REG_5, 0), \
+ BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp)
+
static struct bpf_test tests[] = {
{
"add+sub+mul",
@@ -12441,6 +12459,222 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
},
+ {
+ "reference tracking: leak potential reference",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_0), /* leak reference */
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: leak potential reference on stack",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
+ BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: leak potential reference on stack 2",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
+ BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_ST_MEM(BPF_DW, BPF_REG_4, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: zero potential reference",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_IMM(BPF_REG_0, 0), /* leak reference */
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: copy and zero potential references",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_7, 0), /* leak reference */
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: release reference without check",
+ .insns = {
+ BPF_SK_LOOKUP,
+ /* reference in r0 may be NULL */
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "type=sock_or_null expected=sock",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: release reference",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
+ {
+ "reference tracking: release reference 2",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
+ {
+ "reference tracking: release reference twice",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "type=inv expected=sock",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: release reference twice inside branch",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4), /* goto end */
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "type=inv expected=sock",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: alloc, check, free in one subbranch",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 16),
+ /* if (offsetof(skb, mark) > data_len) exit; */
+ BPF_JMP_REG(BPF_JLE, BPF_REG_0, BPF_REG_3, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_2,
+ offsetof(struct __sk_buff, mark)),
+ BPF_SK_LOOKUP,
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 1), /* mark == 0? */
+ /* Leak reference in R0 */
+ BPF_EXIT_INSN(),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), /* sk NULL? */
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking: alloc, check, free in both subbranches",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 16),
+ /* if (offsetof(skb, mark) > data_len) exit; */
+ BPF_JMP_REG(BPF_JLE, BPF_REG_0, BPF_REG_3, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_2,
+ offsetof(struct __sk_buff, mark)),
+ BPF_SK_LOOKUP,
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 5), /* mark == 0? */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), /* sk NULL? */
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), /* sk NULL? */
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
+ {
+ "reference tracking in call: free reference in subprog",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), /* unchecked reference */
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
{
"pass modified ctx pointer to helper, 1",
.insns = {
@@ -12511,6 +12745,131 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
},
+ {
+ "reference tracking in call: free reference in subprog and outside",
+ .insns = {
+ BPF_SK_LOOKUP,
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), /* unchecked reference */
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 3),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "type=inv expected=sock",
+ .result = REJECT,
+ },
+ {
+ "reference tracking in call: alloc & leak reference in subprog",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 3),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_4),
+ BPF_SK_LOOKUP,
+ /* spill unchecked sk_ptr into stack of caller */
+ BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking in call: alloc in subprog, release outside",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 5),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_SK_LOOKUP,
+ BPF_EXIT_INSN(), /* return sk */
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .retval = POINTER_VALUE,
+ .result = ACCEPT,
+ },
+ {
+ "reference tracking in call: sk_ptr leak into caller stack",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
+ BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 5),
+ /* spill unchecked sk_ptr into stack of caller */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+
+ /* subprog 2 */
+ BPF_SK_LOOKUP,
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .errstr = "Unreleased reference",
+ .result = REJECT,
+ },
+ {
+ "reference tracking in call: sk_ptr spill into caller stack",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+
+ /* subprog 1 */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
+ BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 9),
+ /* spill unchecked sk_ptr into stack of caller */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
+ /* now the sk_ptr is verified, free the reference */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_4, 0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_release),
+ BPF_EXIT_INSN(),
+
+ /* subprog 2 */
+ BPF_SK_LOOKUP,
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 09/11] libbpf: Support loading individual progs
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Allow the individual program load to be invoked. This will help with
testing, where a single ELF may contain several sections, some of which
denote subprograms that are expected to fail verification, along with
some which are expected to pass verification. By allowing programs to be
iterated and individually loaded, each program can be independently
checked against its expected verification result.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
tools/lib/bpf/libbpf.c | 4 ++--
tools/lib/bpf/libbpf.h | 3 +++
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9ca8e0e624d8..b758883bed68 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -227,7 +227,7 @@ struct bpf_object {
};
#define obj_elf_valid(o) ((o)->efile.elf)
-static void bpf_program__unload(struct bpf_program *prog)
+void bpf_program__unload(struct bpf_program *prog)
{
int i;
@@ -1375,7 +1375,7 @@ load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type,
return ret;
}
-static int
+int
bpf_program__load(struct bpf_program *prog,
char *license, u32 kern_version)
{
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index e3b00e23e181..40e4395f1c07 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -126,10 +126,13 @@ void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex);
const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
+int bpf_program__load(struct bpf_program *prog, char *license,
+ u32 kern_version);
int bpf_program__fd(struct bpf_program *prog);
int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
int instance);
int bpf_program__pin(struct bpf_program *prog, const char *path);
+void bpf_program__unload(struct bpf_program *prog);
struct bpf_insn;
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 10/11] selftests/bpf: Add C tests for reference tracking
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Add some tests that demonstrate and test the balanced lookup/free
nature of socket lookup. Section names that start with "fail" represent
programs that are expected to fail verification; all others should
succeed.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
tools/testing/selftests/bpf/Makefile | 2 +-
tools/testing/selftests/bpf/test_progs.c | 38 +++++
.../selftests/bpf/test_sk_lookup_kern.c | 137 ++++++++++++++++++
3 files changed, 176 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/test_sk_lookup_kern.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index fd3851d5c079..a0c9c2208aad 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -35,7 +35,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
test_get_stack_rawtp.o test_sockmap_kern.o test_sockhash_kern.o \
test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
- test_skb_cgroup_id_kern.o bpf_flow.o
+ test_skb_cgroup_id_kern.o bpf_flow.o test_sk_lookup_kern.o
# Order correspond to 'make run_tests' order
TEST_PROGS := test_kmod.sh \
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index 63a671803ed6..e8becca9c521 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -1698,6 +1698,43 @@ static void test_task_fd_query_tp(void)
"sys_enter_read");
}
+static void test_reference_tracking()
+{
+ const char *file = "./test_sk_lookup_kern.o";
+ struct bpf_object *obj;
+ struct bpf_program *prog;
+ __u32 duration;
+ int err = 0;
+
+ obj = bpf_object__open(file);
+ if (IS_ERR(obj)) {
+ error_cnt++;
+ return;
+ }
+
+ bpf_object__for_each_program(prog, obj) {
+ const char *title;
+
+ /* Ignore .text sections */
+ title = bpf_program__title(prog, false);
+ if (strstr(title, ".text") != NULL)
+ continue;
+
+ bpf_program__set_type(prog, BPF_PROG_TYPE_SCHED_CLS);
+
+ /* Expect verifier failure if test name has 'fail' */
+ if (strstr(title, "fail") != NULL) {
+ libbpf_set_print(NULL, NULL, NULL);
+ err = !bpf_program__load(prog, "GPL", 0);
+ libbpf_set_print(printf, printf, NULL);
+ } else {
+ err = bpf_program__load(prog, "GPL", 0);
+ }
+ CHECK(err, title, "\n");
+ }
+ bpf_object__close(obj);
+}
+
int main(void)
{
jit_enabled = is_jit_enabled();
@@ -1719,6 +1756,7 @@ int main(void)
test_get_stack_raw_tp();
test_task_fd_query_rawtp();
test_task_fd_query_tp();
+ test_reference_tracking();
printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/tools/testing/selftests/bpf/test_sk_lookup_kern.c b/tools/testing/selftests/bpf/test_sk_lookup_kern.c
new file mode 100644
index 000000000000..d59a84e80120
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_sk_lookup_kern.c
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+// Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/pkt_cls.h>
+#include <linux/tcp.h>
+#include <sys/socket.h>
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+
+int _version SEC("version") = 1;
+char _license[] SEC("license") = "GPL";
+
+/* Fill 'tuple' with L3 info, and attempt to find L4. On fail, return NULL. */
+static struct bpf_sock_tuple *get_tuple(void *data, __u64 nh_off,
+ void *data_end, __u16 eth_proto,
+ bool *ipv4)
+{
+ struct bpf_sock_tuple *result;
+ __u8 proto = 0;
+ __u64 ihl_len;
+
+ if (eth_proto == bpf_htons(ETH_P_IP)) {
+ struct iphdr *iph = (struct iphdr *)(data + nh_off);
+
+ if (iph + 1 > data_end)
+ return NULL;
+ ihl_len = iph->ihl * 4;
+ proto = iph->protocol;
+ *ipv4 = true;
+ result = (struct bpf_sock_tuple *)&iph->saddr;
+ } else if (eth_proto == bpf_htons(ETH_P_IPV6)) {
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(data + nh_off);
+
+ if (ip6h + 1 > data_end)
+ return NULL;
+ ihl_len = sizeof(*ip6h);
+ proto = ip6h->nexthdr;
+ *ipv4 = true;
+ result = (struct bpf_sock_tuple *)&ip6h->saddr;
+ }
+
+ if (data + nh_off + ihl_len > data_end || proto != IPPROTO_TCP)
+ return NULL;
+
+ return result;
+}
+
+SEC("sk_lookup_success")
+int bpf_sk_lookup_test0(struct __sk_buff *skb)
+{
+ void *data_end = (void *)(long)skb->data_end;
+ void *data = (void *)(long)skb->data;
+ struct ethhdr *eth = (struct ethhdr *)(data);
+ struct bpf_sock_tuple *tuple;
+ struct bpf_sock *sk;
+ size_t tuple_len;
+ bool ipv4;
+
+ if (eth + 1 > data_end)
+ return TC_ACT_SHOT;
+
+ tuple = get_tuple(data, sizeof(*eth), data_end, eth->h_proto, &ipv4);
+ if (!tuple || tuple + sizeof *tuple > data_end)
+ return TC_ACT_SHOT;
+
+ tuple_len = ipv4 ? sizeof(tuple->ipv4) : sizeof(tuple->ipv6);
+ sk = bpf_sk_lookup_tcp(skb, tuple, tuple_len, 0, 0);
+ if (sk)
+ bpf_sk_release(sk, 0);
+ return sk ? TC_ACT_OK : TC_ACT_UNSPEC;
+}
+
+SEC("sk_lookup_success_simple")
+int bpf_sk_lookup_test1(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ if (sk)
+ bpf_sk_release(sk, 0);
+ return 0;
+}
+
+
+SEC("fail_no_release")
+int bpf_sk_lookup_test2(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+
+ bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ return 0;
+}
+
+SEC("fail_release_twice")
+int bpf_sk_lookup_test3(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ bpf_sk_release(sk, 0);
+ bpf_sk_release(sk, 0);
+ return 0;
+}
+
+SEC("fail_release_unchecked")
+int bpf_sk_lookup_test4(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ struct bpf_sock *sk;
+
+ sk = bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+ bpf_sk_release(sk, 0);
+ return 0;
+}
+
+void lookup_no_release(struct __sk_buff *skb)
+{
+ struct bpf_sock_tuple tuple = {};
+ bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), 0, 0);
+}
+
+SEC("fail_no_release_subcall")
+int bpf_sk_lookup_test5(struct __sk_buff *skb)
+{
+ lookup_no_release(skb);
+ return 0;
+}
--
2.17.1
^ permalink raw reply related
* [PATCHv2 bpf-next 11/11] Documentation: Describe bpf reference tracking
From: Joe Stringer @ 2018-09-21 17:10 UTC (permalink / raw)
To: ast
Cc: netdev, daniel, john.fastabend, tgraf, kafai, nitin.hande,
mauricio.vasquez
In-Reply-To: <20180921171043.20823-1-joe@wand.net.nz>
Document the new pointer types in the verifier and how the pointer ID
tracking works to ensure that references which are taken are later
released.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
Documentation/networking/filter.txt | 64 +++++++++++++++++++++++++++++
1 file changed, 64 insertions(+)
diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt
index e6b4ebb2b243..4443ce958862 100644
--- a/Documentation/networking/filter.txt
+++ b/Documentation/networking/filter.txt
@@ -1125,6 +1125,14 @@ pointer type. The types of pointers describe their base, as follows:
PTR_TO_STACK Frame pointer.
PTR_TO_PACKET skb->data.
PTR_TO_PACKET_END skb->data + headlen; arithmetic forbidden.
+ PTR_TO_SOCKET Pointer to struct bpf_sock_ops, implicitly refcounted.
+ PTR_TO_SOCKET_OR_NULL
+ Either a pointer to a socket, or NULL; socket lookup
+ returns this type, which becomes a PTR_TO_SOCKET when
+ checked != NULL. PTR_TO_SOCKET is reference-counted,
+ so programs must release the reference through the
+ socket release function before the end of the program.
+ Arithmetic on these pointers is forbidden.
However, a pointer may be offset from this base (as a result of pointer
arithmetic), and this is tracked in two parts: the 'fixed offset' and 'variable
offset'. The former is used when an exactly-known value (e.g. an immediate
@@ -1171,6 +1179,13 @@ over the Ethernet header, then reads IHL and addes (IHL * 4), the resulting
pointer will have a variable offset known to be 4n+2 for some n, so adding the 2
bytes (NET_IP_ALIGN) gives a 4-byte alignment and so word-sized accesses through
that pointer are safe.
+The 'id' field is also used on PTR_TO_SOCKET and PTR_TO_SOCKET_OR_NULL, common
+to all copies of the pointer returned from a socket lookup. This has similar
+behaviour to the handling for PTR_TO_MAP_VALUE_OR_NULL->PTR_TO_MAP_VALUE, but
+it also handles reference tracking for the pointer. PTR_TO_SOCKET implicitly
+represents a reference to the corresponding 'struct sock'. To ensure that the
+reference is not leaked, it is imperative to NULL-check the reference and in
+the non-NULL case, and pass the valid reference to the socket release function.
Direct packet access
--------------------
@@ -1444,6 +1459,55 @@ Error:
8: (7a) *(u64 *)(r0 +0) = 1
R0 invalid mem access 'imm'
+Program that performs a socket lookup then sets the pointer to NULL without
+checking it:
+value:
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_MOV64_IMM(BPF_REG_3, 4),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_MOV64_IMM(BPF_REG_5, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+Error:
+ 0: (b7) r2 = 0
+ 1: (63) *(u32 *)(r10 -8) = r2
+ 2: (bf) r2 = r10
+ 3: (07) r2 += -8
+ 4: (b7) r3 = 4
+ 5: (b7) r4 = 0
+ 6: (b7) r5 = 0
+ 7: (85) call bpf_sk_lookup_tcp#65
+ 8: (b7) r0 = 0
+ 9: (95) exit
+ Unreleased reference id=1, alloc_insn=7
+
+Program that performs a socket lookup but does not NULL-check the returned
+value:
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_MOV64_IMM(BPF_REG_3, 4),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_MOV64_IMM(BPF_REG_5, 0),
+ BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp),
+ BPF_EXIT_INSN(),
+Error:
+ 0: (b7) r2 = 0
+ 1: (63) *(u32 *)(r10 -8) = r2
+ 2: (bf) r2 = r10
+ 3: (07) r2 += -8
+ 4: (b7) r3 = 4
+ 5: (b7) r4 = 0
+ 6: (b7) r5 = 0
+ 7: (85) call bpf_sk_lookup_tcp#65
+ 8: (95) exit
+ Unreleased reference id=1, alloc_insn=7
+
Testing
-------
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next 7/9] selftests/bpf: add verifier per-cpu cgroup storage tests
From: Roman Gushchin @ 2018-09-21 17:14 UTC (permalink / raw)
To: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Kernel Team, Roman Gushchin,
Daniel Borkmann, Alexei Starovoitov
In-Reply-To: <20180921171353.11050-1-guro@fb.com>
This commits adds verifier tests covering per-cpu cgroup storage
functionality. There are 6 new tests, which are exactly the same
as for shared cgroup storage, but do use per-cpu cgroup storage
map.
Expected output:
$ ./test_verifier
#0/u add+sub+mul OK
#0/p add+sub+mul OK
...
#286/p invalid cgroup storage access 6 OK
#287/p valid per-cpu cgroup storage access OK
#288/p invalid per-cpu cgroup storage access 1 OK
#289/p invalid per-cpu cgroup storage access 2 OK
#290/p invalid per-cpu cgroup storage access 3 OK
#291/p invalid per-cpu cgroup storage access 4 OK
#292/p invalid per-cpu cgroup storage access 5 OK
#293/p invalid per-cpu cgroup storage access 6 OK
#294/p multiple registers share map_lookup_elem result OK
...
#662/p mov64 src == dst OK
#663/p mov64 src != dst OK
Summary: 914 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
---
tools/testing/selftests/bpf/test_verifier.c | 139 +++++++++++++++++++-
1 file changed, 133 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 67c412d19c09..c7d25f23baf9 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -68,6 +68,7 @@ struct bpf_test {
int fixup_prog2[MAX_FIXUPS];
int fixup_map_in_map[MAX_FIXUPS];
int fixup_cgroup_storage[MAX_FIXUPS];
+ int fixup_percpu_cgroup_storage[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
uint32_t retval;
@@ -4676,7 +4677,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
},
{
- "invalid per-cgroup storage access 3",
+ "invalid cgroup storage access 3",
.insns = {
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
@@ -4743,6 +4744,121 @@ static struct bpf_test tests[] = {
.errstr = "get_local_storage() doesn't support non-zero flags",
.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
},
+ {
+ "valid per-cpu cgroup storage access",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_percpu_cgroup_storage = { 1 },
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map1 = { 1 },
+ .result = REJECT,
+ .errstr = "cannot pass map_type 1 into func bpf_get_local_storage",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 1),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .errstr = "fd 1 is not pointing to valid bpf_map",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 256),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_percpu_cgroup_storage = { 1 },
+ .result = REJECT,
+ .errstr = "invalid access to map value, value_size=64 off=256 size=4",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 4",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, -2),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_cgroup_storage = { 1 },
+ .result = REJECT,
+ .errstr = "invalid access to map value, value_size=64 off=-2 size=4",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 5",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_2, 7),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_percpu_cgroup_storage = { 1 },
+ .result = REJECT,
+ .errstr = "get_local_storage() doesn't support non-zero flags",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid per-cpu cgroup storage access 6",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_local_storage),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_percpu_cgroup_storage = { 1 },
+ .result = REJECT,
+ .errstr = "get_local_storage() doesn't support non-zero flags",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
{
"multiple registers share map_lookup_elem result",
.insns = {
@@ -12615,15 +12731,17 @@ static int create_map_in_map(void)
return outer_map_fd;
}
-static int create_cgroup_storage(void)
+static int create_cgroup_storage(bool percpu)
{
+ enum bpf_map_type type = percpu ? BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE :
+ BPF_MAP_TYPE_CGROUP_STORAGE;
int fd;
- fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE,
- sizeof(struct bpf_cgroup_storage_key),
+ fd = bpf_create_map(type, sizeof(struct bpf_cgroup_storage_key),
TEST_DATA_LEN, 0, 0);
if (fd < 0)
- printf("Failed to create array '%s'!\n", strerror(errno));
+ printf("Failed to create cgroup storage '%s'!\n",
+ strerror(errno));
return fd;
}
@@ -12641,6 +12759,7 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog,
int *fixup_prog2 = test->fixup_prog2;
int *fixup_map_in_map = test->fixup_map_in_map;
int *fixup_cgroup_storage = test->fixup_cgroup_storage;
+ int *fixup_percpu_cgroup_storage = test->fixup_percpu_cgroup_storage;
if (test->fill_helper)
test->fill_helper(test);
@@ -12710,12 +12829,20 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog,
}
if (*fixup_cgroup_storage) {
- map_fds[7] = create_cgroup_storage();
+ map_fds[7] = create_cgroup_storage(false);
do {
prog[*fixup_cgroup_storage].imm = map_fds[7];
fixup_cgroup_storage++;
} while (*fixup_cgroup_storage);
}
+
+ if (*fixup_percpu_cgroup_storage) {
+ map_fds[8] = create_cgroup_storage(true);
+ do {
+ prog[*fixup_percpu_cgroup_storage].imm = map_fds[8];
+ fixup_percpu_cgroup_storage++;
+ } while (*fixup_percpu_cgroup_storage);
+ }
}
static void do_test_single(struct bpf_test *test, bool unpriv,
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next 1/9] bpf: extend cgroup bpf core to allow multiple cgroup storage types
From: Roman Gushchin @ 2018-09-21 17:14 UTC (permalink / raw)
To: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Kernel Team, Roman Gushchin,
Daniel Borkmann, Alexei Starovoitov
In order to introduce per-cpu cgroup storage, let's generalize
bpf cgroup core to support multiple cgroup storage types.
Potentially, per-node cgroup storage can be added later.
This commit is mostly a formal change that replaces
cgroup_storage pointer with a array of cgroup_storage pointers.
It doesn't actually introduce a new storage type,
it will be done later.
Each bpf program is now able to have one cgroup storage of each type.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
---
include/linux/bpf-cgroup.h | 38 ++++++++++++++------
include/linux/bpf.h | 11 ++++--
kernel/bpf/cgroup.c | 74 ++++++++++++++++++++++++++------------
kernel/bpf/helpers.c | 15 ++++----
kernel/bpf/local_storage.c | 18 ++++++----
kernel/bpf/syscall.c | 9 +++--
kernel/bpf/verifier.c | 8 +++--
net/bpf/test_run.c | 20 +++++++----
8 files changed, 136 insertions(+), 57 deletions(-)
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index f91b0f8ff3a9..e9871b012dac 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -2,6 +2,7 @@
#ifndef _BPF_CGROUP_H
#define _BPF_CGROUP_H
+#include <linux/bpf.h>
#include <linux/errno.h>
#include <linux/jump_label.h>
#include <linux/percpu.h>
@@ -22,7 +23,10 @@ struct bpf_cgroup_storage;
extern struct static_key_false cgroup_bpf_enabled_key;
#define cgroup_bpf_enabled static_branch_unlikely(&cgroup_bpf_enabled_key)
-DECLARE_PER_CPU(void*, bpf_cgroup_storage);
+DECLARE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
+
+#define for_each_cgroup_storage_type(stype) \
+ for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
struct bpf_cgroup_storage_map;
@@ -43,7 +47,7 @@ struct bpf_cgroup_storage {
struct bpf_prog_list {
struct list_head node;
struct bpf_prog *prog;
- struct bpf_cgroup_storage *storage;
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE];
};
struct bpf_prog_array;
@@ -101,18 +105,29 @@ int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
short access, enum bpf_attach_type type);
-static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage)
+static inline enum bpf_cgroup_storage_type cgroup_storage_type(
+ struct bpf_map *map)
{
+ return BPF_CGROUP_STORAGE_SHARED;
+}
+
+static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage
+ *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
+{
+ enum bpf_cgroup_storage_type stype;
struct bpf_storage_buffer *buf;
- if (!storage)
- return;
+ for_each_cgroup_storage_type(stype) {
+ if (!storage[stype])
+ continue;
- buf = READ_ONCE(storage->buf);
- this_cpu_write(bpf_cgroup_storage, &buf->data[0]);
+ buf = READ_ONCE(storage[stype]->buf);
+ this_cpu_write(bpf_cgroup_storage[stype], &buf->data[0]);
+ }
}
-struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog);
+struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
+ enum bpf_cgroup_storage_type stype);
void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
struct cgroup *cgroup,
@@ -265,13 +280,14 @@ static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
return -EINVAL;
}
-static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage) {}
+static inline void bpf_cgroup_storage_set(
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {}
static inline int bpf_cgroup_storage_assign(struct bpf_prog *prog,
struct bpf_map *map) { return 0; }
static inline void bpf_cgroup_storage_release(struct bpf_prog *prog,
struct bpf_map *map) {}
static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
- struct bpf_prog *prog) { return 0; }
+ struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return 0; }
static inline void bpf_cgroup_storage_free(
struct bpf_cgroup_storage *storage) {}
@@ -293,6 +309,8 @@ static inline void bpf_cgroup_storage_free(
#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
#define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
+#define for_each_cgroup_storage_type(stype) for (; false; )
+
#endif /* CONFIG_CGROUP_BPF */
#endif /* _BPF_CGROUP_H */
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 988a00797bcd..b457fbe7b70b 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -272,6 +272,13 @@ struct bpf_prog_offload {
u32 jited_len;
};
+enum bpf_cgroup_storage_type {
+ BPF_CGROUP_STORAGE_SHARED,
+ __BPF_CGROUP_STORAGE_MAX
+};
+
+#define MAX_BPF_CGROUP_STORAGE_TYPE __BPF_CGROUP_STORAGE_MAX
+
struct bpf_prog_aux {
atomic_t refcnt;
u32 used_map_cnt;
@@ -289,7 +296,7 @@ struct bpf_prog_aux {
struct bpf_prog *prog;
struct user_struct *user;
u64 load_time; /* ns since boottime */
- struct bpf_map *cgroup_storage;
+ struct bpf_map *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE];
char name[BPF_OBJ_NAME_LEN];
#ifdef CONFIG_SECURITY
void *security;
@@ -358,7 +365,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
*/
struct bpf_prog_array_item {
struct bpf_prog *prog;
- struct bpf_cgroup_storage *cgroup_storage;
+ struct bpf_cgroup_storage *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE];
};
struct bpf_prog_array {
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index 6a7d931bbc55..065c3d9ff8eb 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -25,6 +25,7 @@ EXPORT_SYMBOL(cgroup_bpf_enabled_key);
*/
void cgroup_bpf_put(struct cgroup *cgrp)
{
+ enum bpf_cgroup_storage_type stype;
unsigned int type;
for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) {
@@ -34,8 +35,10 @@ void cgroup_bpf_put(struct cgroup *cgrp)
list_for_each_entry_safe(pl, tmp, progs, node) {
list_del(&pl->node);
bpf_prog_put(pl->prog);
- bpf_cgroup_storage_unlink(pl->storage);
- bpf_cgroup_storage_free(pl->storage);
+ for_each_cgroup_storage_type(stype) {
+ bpf_cgroup_storage_unlink(pl->storage[stype]);
+ bpf_cgroup_storage_free(pl->storage[stype]);
+ }
kfree(pl);
static_branch_dec(&cgroup_bpf_enabled_key);
}
@@ -97,6 +100,7 @@ static int compute_effective_progs(struct cgroup *cgrp,
enum bpf_attach_type type,
struct bpf_prog_array __rcu **array)
{
+ enum bpf_cgroup_storage_type stype;
struct bpf_prog_array *progs;
struct bpf_prog_list *pl;
struct cgroup *p = cgrp;
@@ -125,7 +129,9 @@ static int compute_effective_progs(struct cgroup *cgrp,
continue;
progs->items[cnt].prog = pl->prog;
- progs->items[cnt].cgroup_storage = pl->storage;
+ for_each_cgroup_storage_type(stype)
+ progs->items[cnt].cgroup_storage[stype] =
+ pl->storage[stype];
cnt++;
}
} while ((p = cgroup_parent(p)));
@@ -232,7 +238,9 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
{
struct list_head *progs = &cgrp->bpf.progs[type];
struct bpf_prog *old_prog = NULL;
- struct bpf_cgroup_storage *storage, *old_storage = NULL;
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE],
+ *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {NULL};
+ enum bpf_cgroup_storage_type stype;
struct bpf_prog_list *pl;
bool pl_was_allocated;
int err;
@@ -254,34 +262,44 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
if (prog_list_length(progs) >= BPF_CGROUP_MAX_PROGS)
return -E2BIG;
- storage = bpf_cgroup_storage_alloc(prog);
- if (IS_ERR(storage))
- return -ENOMEM;
+ for_each_cgroup_storage_type(stype) {
+ storage[stype] = bpf_cgroup_storage_alloc(prog, stype);
+ if (IS_ERR(storage[stype])) {
+ storage[stype] = NULL;
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
+ return -ENOMEM;
+ }
+ }
if (flags & BPF_F_ALLOW_MULTI) {
list_for_each_entry(pl, progs, node) {
if (pl->prog == prog) {
/* disallow attaching the same prog twice */
- bpf_cgroup_storage_free(storage);
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
return -EINVAL;
}
}
pl = kmalloc(sizeof(*pl), GFP_KERNEL);
if (!pl) {
- bpf_cgroup_storage_free(storage);
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
return -ENOMEM;
}
pl_was_allocated = true;
pl->prog = prog;
- pl->storage = storage;
+ for_each_cgroup_storage_type(stype)
+ pl->storage[stype] = storage[stype];
list_add_tail(&pl->node, progs);
} else {
if (list_empty(progs)) {
pl = kmalloc(sizeof(*pl), GFP_KERNEL);
if (!pl) {
- bpf_cgroup_storage_free(storage);
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
return -ENOMEM;
}
pl_was_allocated = true;
@@ -289,12 +307,15 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
} else {
pl = list_first_entry(progs, typeof(*pl), node);
old_prog = pl->prog;
- old_storage = pl->storage;
- bpf_cgroup_storage_unlink(old_storage);
+ for_each_cgroup_storage_type(stype) {
+ old_storage[stype] = pl->storage[stype];
+ bpf_cgroup_storage_unlink(old_storage[stype]);
+ }
pl_was_allocated = false;
}
pl->prog = prog;
- pl->storage = storage;
+ for_each_cgroup_storage_type(stype)
+ pl->storage[stype] = storage[stype];
}
cgrp->bpf.flags[type] = flags;
@@ -304,21 +325,27 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
goto cleanup;
static_branch_inc(&cgroup_bpf_enabled_key);
- if (old_storage)
- bpf_cgroup_storage_free(old_storage);
+ for_each_cgroup_storage_type(stype) {
+ if (!old_storage[stype])
+ continue;
+ bpf_cgroup_storage_free(old_storage[stype]);
+ }
if (old_prog) {
bpf_prog_put(old_prog);
static_branch_dec(&cgroup_bpf_enabled_key);
}
- bpf_cgroup_storage_link(storage, cgrp, type);
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_link(storage[stype], cgrp, type);
return 0;
cleanup:
/* and cleanup the prog list */
pl->prog = old_prog;
- bpf_cgroup_storage_free(pl->storage);
- pl->storage = old_storage;
- bpf_cgroup_storage_link(old_storage, cgrp, type);
+ for_each_cgroup_storage_type(stype) {
+ bpf_cgroup_storage_free(pl->storage[stype]);
+ pl->storage[stype] = old_storage[stype];
+ bpf_cgroup_storage_link(old_storage[stype], cgrp, type);
+ }
if (pl_was_allocated) {
list_del(&pl->node);
kfree(pl);
@@ -339,6 +366,7 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
enum bpf_attach_type type, u32 unused_flags)
{
struct list_head *progs = &cgrp->bpf.progs[type];
+ enum bpf_cgroup_storage_type stype;
u32 flags = cgrp->bpf.flags[type];
struct bpf_prog *old_prog = NULL;
struct bpf_prog_list *pl;
@@ -385,8 +413,10 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
/* now can actually delete it from this cgroup list */
list_del(&pl->node);
- bpf_cgroup_storage_unlink(pl->storage);
- bpf_cgroup_storage_free(pl->storage);
+ for_each_cgroup_storage_type(stype) {
+ bpf_cgroup_storage_unlink(pl->storage[stype]);
+ bpf_cgroup_storage_free(pl->storage[stype]);
+ }
kfree(pl);
if (list_empty(progs))
/* last program was detached, reset flags to zero */
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 1991466b8327..9070b2ace6aa 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -194,16 +194,18 @@ const struct bpf_func_proto bpf_get_current_cgroup_id_proto = {
.ret_type = RET_INTEGER,
};
-DECLARE_PER_CPU(void*, bpf_cgroup_storage);
+#ifdef CONFIG_CGROUP_BPF
+DECLARE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
{
- /* map and flags arguments are not used now,
- * but provide an ability to extend the API
- * for other types of local storages.
- * verifier checks that their values are correct.
+ /* flags argument is not used now,
+ * but provides an ability to extend the API.
+ * verifier checks that its value is correct.
*/
- return (unsigned long) this_cpu_read(bpf_cgroup_storage);
+ enum bpf_cgroup_storage_type stype = cgroup_storage_type(map);
+
+ return (unsigned long) this_cpu_read(bpf_cgroup_storage[stype]);
}
const struct bpf_func_proto bpf_get_local_storage_proto = {
@@ -214,3 +216,4 @@ const struct bpf_func_proto bpf_get_local_storage_proto = {
.arg2_type = ARG_ANYTHING,
};
#endif
+#endif
diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 22ad967d1e5f..0bd9f19fc557 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -7,7 +7,7 @@
#include <linux/rbtree.h>
#include <linux/slab.h>
-DEFINE_PER_CPU(void*, bpf_cgroup_storage);
+DEFINE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
#ifdef CONFIG_CGROUP_BPF
@@ -251,6 +251,7 @@ const struct bpf_map_ops cgroup_storage_map_ops = {
int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map)
{
+ enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map);
struct bpf_cgroup_storage_map *map = map_to_storage(_map);
int ret = -EBUSY;
@@ -258,11 +259,12 @@ int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map)
if (map->prog && map->prog != prog)
goto unlock;
- if (prog->aux->cgroup_storage && prog->aux->cgroup_storage != _map)
+ if (prog->aux->cgroup_storage[stype] &&
+ prog->aux->cgroup_storage[stype] != _map)
goto unlock;
map->prog = prog;
- prog->aux->cgroup_storage = _map;
+ prog->aux->cgroup_storage[stype] = _map;
ret = 0;
unlock:
spin_unlock_bh(&map->lock);
@@ -272,24 +274,26 @@ int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map)
void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *_map)
{
+ enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map);
struct bpf_cgroup_storage_map *map = map_to_storage(_map);
spin_lock_bh(&map->lock);
if (map->prog == prog) {
- WARN_ON(prog->aux->cgroup_storage != _map);
+ WARN_ON(prog->aux->cgroup_storage[stype] != _map);
map->prog = NULL;
- prog->aux->cgroup_storage = NULL;
+ prog->aux->cgroup_storage[stype] = NULL;
}
spin_unlock_bh(&map->lock);
}
-struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog)
+struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
+ enum bpf_cgroup_storage_type stype)
{
struct bpf_cgroup_storage *storage;
struct bpf_map *map;
u32 pages;
- map = prog->aux->cgroup_storage;
+ map = prog->aux->cgroup_storage[stype];
if (!map)
return NULL;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b3c2d09bcf7a..8c91d2b41b1e 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -988,10 +988,15 @@ static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
/* drop refcnt on maps used by eBPF program and free auxilary data */
static void free_used_maps(struct bpf_prog_aux *aux)
{
+ enum bpf_cgroup_storage_type stype;
int i;
- if (aux->cgroup_storage)
- bpf_cgroup_storage_release(aux->prog, aux->cgroup_storage);
+ for_each_cgroup_storage_type(stype) {
+ if (!aux->cgroup_storage[stype])
+ continue;
+ bpf_cgroup_storage_release(aux->prog,
+ aux->cgroup_storage[stype]);
+ }
for (i = 0; i < aux->used_map_cnt; i++)
bpf_map_put(aux->used_maps[i]);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 8ccbff4fff93..e75f36de91d6 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5171,11 +5171,15 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env)
/* drop refcnt of maps used by the rejected program */
static void release_maps(struct bpf_verifier_env *env)
{
+ enum bpf_cgroup_storage_type stype;
int i;
- if (env->prog->aux->cgroup_storage)
+ for_each_cgroup_storage_type(stype) {
+ if (!env->prog->aux->cgroup_storage[stype])
+ continue;
bpf_cgroup_storage_release(env->prog,
- env->prog->aux->cgroup_storage);
+ env->prog->aux->cgroup_storage[stype]);
+ }
for (i = 0; i < env->used_map_cnt; i++)
bpf_map_put(env->used_maps[i]);
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index f4078830ea50..0c423b8cd75c 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -12,7 +12,7 @@
#include <linux/sched/signal.h>
static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx,
- struct bpf_cgroup_storage *storage)
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
{
u32 ret;
@@ -28,13 +28,20 @@ static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx,
static u32 bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *time)
{
- struct bpf_cgroup_storage *storage = NULL;
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { 0 };
+ enum bpf_cgroup_storage_type stype;
u64 time_start, time_spent = 0;
u32 ret = 0, i;
- storage = bpf_cgroup_storage_alloc(prog);
- if (IS_ERR(storage))
- return PTR_ERR(storage);
+ for_each_cgroup_storage_type(stype) {
+ storage[stype] = bpf_cgroup_storage_alloc(prog, stype);
+ if (IS_ERR(storage[stype])) {
+ storage[stype] = NULL;
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
+ return -ENOMEM;
+ }
+ }
if (!repeat)
repeat = 1;
@@ -53,7 +60,8 @@ static u32 bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *time)
do_div(time_spent, repeat);
*time = time_spent > U32_MAX ? U32_MAX : (u32)time_spent;
- bpf_cgroup_storage_free(storage);
+ for_each_cgroup_storage_type(stype)
+ bpf_cgroup_storage_free(storage[stype]);
return ret;
}
--
2.17.1
^ permalink raw reply related
* Re: [PATCH net-next] ravb: Disable Pause Advertisement
From: Sergei Shtylyov @ 2018-09-21 17:25 UTC (permalink / raw)
To: Andrew Lunn, David Miller; +Cc: Simon Horman, Florian Fainelli, netdev
In-Reply-To: <1537537946-24786-1-git-send-email-andrew@lunn.ch>
Hello!
You forgot to CC me. :-/
On 09/21/2018 04:52 PM, Andrew Lunn wrote:
> The previous commit to ravb had the side effect of making the PHY
> advertise Pause and Asym Pause, which previously did not happen. By
> default, phydev->supported has both forms of pause enabled, but
> phydev->advertising does not. The new phy_remove_link_mode() copies
> phydev->supported to phydev->advertising after removing the requested
> link mode. These Pause configuration bits appears it stops the PHY
> from completing Auto-Neg and the link remains down. Be explicit and
> remove the Pause and Asym Pause modes, so restoring the old behavior.
>
> Reported-by: Simon Horman <horms@verge.net.au>
> Fixes: 41124fa64d4b ("net: ethernet: Add helper to remove a supported link mode")
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[...]
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
MBR, Sergei
^ permalink raw reply
* Re: [PATCH net] af_key: free SKBs under RCU protection
From: Eric Dumazet @ 2018-09-21 17:40 UTC (permalink / raw)
To: stranche, Eric Dumazet; +Cc: netdev, steffen.klassert
In-Reply-To: <a1b484c544c9f631246374ccf09e491f@codeaurora.org>
On 09/21/2018 10:09 AM, stranche@codeaurora.org wrote:
> I also tried reverting 7f6b9dbd5afb ("af_key: locking change") and running the
> test there and I still see the crash, so it doesn't seem to be an RCU specific
> issue.
>
> Is there anything else that could be causing this?
What about you share your repro ?
^ permalink raw reply
* [PATCH net] net/ipv4: avoid compile error in fib_info_nh_uses_dev
From: Eric Dumazet @ 2018-09-21 17:58 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet, David Ahern
net/ipv4/fib_frontend.c: In function 'fib_info_nh_uses_dev':
net/ipv4/fib_frontend.c:322:6: error: unused variable 'ret' [-Werror=unused-variable]
cc1: all warnings being treated as errors
Fixes: 78f2756c5fc0 ("net/ipv4: Move device validation to helper")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@gmail.com>
---
net/ipv4/fib_frontend.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 222b968de94cbff98c4a1b4a2f298b2e68452984..30e2bcc3ef2a293568076228fecf3cf07ba01f20 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -318,9 +318,9 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev)
{
bool dev_match = false;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
int ret;
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
for (ret = 0; ret < fi->fib_nhs; ret++) {
struct fib_nh *nh = &fi->fib_nh[ret];
--
2.19.0.444.g18242da7ef-goog
^ permalink raw reply related
* Re: [PATCH net] net/ipv4: avoid compile error in fib_info_nh_uses_dev
From: Eric Dumazet @ 2018-09-21 18:01 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern
In-Reply-To: <20180921175807.85168-1-edumazet@google.com>
On 09/21/2018 10:58 AM, Eric Dumazet wrote:
> net/ipv4/fib_frontend.c: In function 'fib_info_nh_uses_dev':
> net/ipv4/fib_frontend.c:322:6: error: unused variable 'ret' [-Werror=unused-variable]
> cc1: all warnings being treated as errors
>
> Fixes: 78f2756c5fc0 ("net/ipv4: Move device validation to helper")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: David Ahern <dsahern@gmail.com>
>
This targets net-next tree, sorry for the wrong tag in title.
^ permalink raw reply
* Re: [PATCH net] net/ipv4: avoid compile error in fib_info_nh_uses_dev
From: David Ahern @ 2018-09-21 18:03 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller; +Cc: netdev, Eric Dumazet
In-Reply-To: <20180921175807.85168-1-edumazet@google.com>
On 9/21/18 10:58 AM, Eric Dumazet wrote:
> net/ipv4/fib_frontend.c: In function 'fib_info_nh_uses_dev':
> net/ipv4/fib_frontend.c:322:6: error: unused variable 'ret' [-Werror=unused-variable]
> cc1: all warnings being treated as errors
>
> Fixes: 78f2756c5fc0 ("net/ipv4: Move device validation to helper")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: David Ahern <dsahern@gmail.com>
> ---
> net/ipv4/fib_frontend.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
> index 222b968de94cbff98c4a1b4a2f298b2e68452984..30e2bcc3ef2a293568076228fecf3cf07ba01f20 100644
> --- a/net/ipv4/fib_frontend.c
> +++ b/net/ipv4/fib_frontend.c
> @@ -318,9 +318,9 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
> bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev)
> {
> bool dev_match = false;
> +#ifdef CONFIG_IP_ROUTE_MULTIPATH
> int ret;
>
> -#ifdef CONFIG_IP_ROUTE_MULTIPATH
> for (ret = 0; ret < fi->fib_nhs; ret++) {
> struct fib_nh *nh = &fi->fib_nh[ret];
>
>
Reviewed-by: David Ahern <dsahern@gmail.com>
Thanks for the fix.
^ permalink raw reply
* [PATCH net-next 1/3] ipv6: discard IP frag queue on more errors
From: Peter Oskolkov @ 2018-09-21 18:17 UTC (permalink / raw)
To: David Miller, netdev; +Cc: Peter Oskolkov
This is similar to how ipv4 now behaves:
commit 0ff89efb5246 ("ip: fail fast on IP defrag errors").
Signed-off-by: Peter Oskolkov <posk@google.com>
---
net/ipv6/reassembly.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index f1b1ff30fe5b..536c1d172cba 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -145,7 +145,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
*/
if (end < fq->q.len ||
((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len))
- goto err;
+ goto discard_fq;
fq->q.flags |= INET_FRAG_LAST_IN;
fq->q.len = end;
} else {
@@ -162,20 +162,20 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
if (end > fq->q.len) {
/* Some bits beyond end -> corruption. */
if (fq->q.flags & INET_FRAG_LAST_IN)
- goto err;
+ goto discard_fq;
fq->q.len = end;
}
}
if (end == offset)
- goto err;
+ goto discard_fq;
/* Point into the IP datagram 'data' part. */
if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data))
- goto err;
+ goto discard_fq;
if (pskb_trim_rcsum(skb, end - offset))
- goto err;
+ goto discard_fq;
/* Find out which fragments are in front and at the back of us
* in the chain of fragments so far. We must know where to put
@@ -418,6 +418,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
rcu_read_lock();
__IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
rcu_read_unlock();
+ inet_frag_kill(&fq->q);
return -1;
}
--
2.19.0.444.g18242da7ef-goog
^ permalink raw reply related
* Re: [Intel-wired-lan] [PATCH v2 1/4] i40e: clean zero-copy XDP Tx ring on shutdown/reset
From: Jeff Kirsher @ 2018-09-21 18:17 UTC (permalink / raw)
To: Björn Töpel, intel-wired-lan
Cc: Netdev, Björn Töpel, Magnus Karlsson, Karlsson, Magnus,
Jakub Kicinski, Daniel Borkmann, ast
In-Reply-To: <CAJ+HfNgYwWo1Cmx81SGSRAPEtVzKvogaWSL17vPuorYpx-U-Lw@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 1272 bytes --]
On Fri, 2018-09-21 at 09:35 +0200, Björn Töpel wrote:
> > --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
> > +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
> > @@ -830,3 +830,33 @@ int i40e_xsk_async_xmit(struct net_device
> > *dev, u32 queue_id)
> >
> > return 0;
> > }
> > +
> > +/**
> > + * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
> > + * @xdp_ring: XDP Tx ring
> > + **/
> > +void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
> > +{
> > + u16 ntc = tx_ring->next_to_clean, ntu = tx_ring-
> > >next_to_use;
> > + struct xdp_umem *umem = tx_ring->xsk_umem;
> > + struct i40e_tx_buffer *tx_bi;
> > + u32 xsk_frames = 0;
> > +
> > + while (ntc != ntu) {
> > + tx_bi = &tx_ring->tx_bi[ntc];
> > +
> > + if (tx_bi->xdpf)
> > + i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
> > + else
> > + xsk_frames++;
> > +
> > + tx_bi->xdpf = NULL;
> > +
> > + ntc++;
> > + if (ntc > tx_ring->count)
>
> This is an off-by-one error, and should be:
> if (ntc == tx_ring->count)
>
> Can you fix it up, or should I respin the patch?
I can fix it up.
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply
* [PATCH net-next 2/3] net/ipfrag: let ip[6]frag_high_thresh in ns be higher than in init_net
From: Peter Oskolkov @ 2018-09-21 18:17 UTC (permalink / raw)
To: David Miller, netdev; +Cc: Peter Oskolkov
In-Reply-To: <20180921181717.113242-1-posk@google.com>
Currently, ip[6]frag_high_thresh sysctl values in new namespaces are
hard-limited to those of the root/init ns.
There are at least two use cases when it would be desirable to
set the high_thresh values higher in a child namespace vs the global hard
limit:
- a security/ddos protection policy may lower the thresholds in the
root/init ns but allow for a special exception in a child namespace
- testing: a test running in a namespace may want to set these
thresholds higher in its namespace than what is in the root/init ns
The new behavior:
# ip netns add testns
# ip netns exec testns bash
# sysctl -w net.ipv4.ipfrag_high_thresh=9000000
net.ipv4.ipfrag_high_thresh = 9000000
# sysctl net.ipv4.ipfrag_high_thresh
net.ipv4.ipfrag_high_thresh = 9000000
# sysctl -w net.ipv6.ip6frag_high_thresh=9000000
net.ipv6.ip6frag_high_thresh = 9000000
# sysctl net.ipv6.ip6frag_high_thresh
net.ipv6.ip6frag_high_thresh = 9000000
The old behavior:
# ip netns add testns
# ip netns exec testns bash
# sysctl -w net.ipv4.ipfrag_high_thresh=9000000
net.ipv4.ipfrag_high_thresh = 9000000
# sysctl net.ipv4.ipfrag_high_thresh
net.ipv4.ipfrag_high_thresh = 4194304
# sysctl -w net.ipv6.ip6frag_high_thresh=9000000
net.ipv6.ip6frag_high_thresh = 9000000
# sysctl net.ipv6.ip6frag_high_thresh
net.ipv6.ip6frag_high_thresh = 4194304
Signed-off-by: Peter Oskolkov <posk@google.com>
---
net/ieee802154/6lowpan/reassembly.c | 1 -
net/ipv4/ip_fragment.c | 1 -
net/ipv6/reassembly.c | 1 -
3 files changed, 3 deletions(-)
diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c
index 09ffbf5ce8fa..d14226ecfde4 100644
--- a/net/ieee802154/6lowpan/reassembly.c
+++ b/net/ieee802154/6lowpan/reassembly.c
@@ -463,7 +463,6 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
table[0].data = &ieee802154_lowpan->frags.high_thresh;
table[0].extra1 = &ieee802154_lowpan->frags.low_thresh;
- table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh;
table[1].data = &ieee802154_lowpan->frags.low_thresh;
table[1].extra2 = &ieee802154_lowpan->frags.high_thresh;
table[2].data = &ieee802154_lowpan->frags.timeout;
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 13f4d189e12b..9b0158fa431f 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -822,7 +822,6 @@ static int __net_init ip4_frags_ns_ctl_register(struct net *net)
table[0].data = &net->ipv4.frags.high_thresh;
table[0].extra1 = &net->ipv4.frags.low_thresh;
- table[0].extra2 = &init_net.ipv4.frags.high_thresh;
table[1].data = &net->ipv4.frags.low_thresh;
table[1].extra2 = &net->ipv4.frags.high_thresh;
table[2].data = &net->ipv4.frags.timeout;
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 536c1d172cba..5c3c92713096 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -554,7 +554,6 @@ static int __net_init ip6_frags_ns_sysctl_register(struct net *net)
table[0].data = &net->ipv6.frags.high_thresh;
table[0].extra1 = &net->ipv6.frags.low_thresh;
- table[0].extra2 = &init_net.ipv6.frags.high_thresh;
table[1].data = &net->ipv6.frags.low_thresh;
table[1].extra2 = &net->ipv6.frags.high_thresh;
table[2].data = &net->ipv6.frags.timeout;
--
2.19.0.444.g18242da7ef-goog
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