* [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets
@ 2026-03-24 12:20 Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs Xu Kuohai
` (4 more replies)
0 siblings, 5 replies; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
On architectures with CFI protection enabled that require landing pad
instructions at indirect jump targets, such as x86 with CET/IBT enabled
and arm64 with BTI enabled, kernel panics when an indirect jump lands on
a target without landing pad. Therefore, the JIT must emit landing pad
instructions for indirect jump targets.
The verifier already recognizes which instructions are indirect jump
targets during the verification phase. So we can store this information
in env->insn_aux_data and pass it to the JIT as new parameter, so the JIT
knows which instructions are indirect jump targets.
During JIT, constants blinding is performed. It rewrites the private copy
of instructions for the JITed program, but it does not adjust the global
env->insn_aux_data array. As a result, after constants blinding, the
instruction indexes used by JIT may no longer match the indexes in
env->insn_aux_data, so the JIT can not lookup env->insn_aux_data directly.
To avoid this mismatch, and considering that all existing arch-specific JITs
already implement constants blinding with largely duplicated code, move
constants blinding from JIT to generic code.
v10:
- Fix the incorrect call_imm restore in jit_subprogs
- Define a dummy void version of bpf_jit_prog_release_other and
bpf_patch_insn_data when the corresponding config is not set
- Remove the unnecessary #ifdef in x86_64 JIT (Leon Hwang)
v9: https://lore.kernel.org/bpf/20260312170255.3427799-1-xukuohai@huaweicloud.com/
- Make constant blinding available for classic bpf (Eduard)
- Clear prog->bpf_func, prog->jited ... on the error path of extra pass (Eduard)
- Fix spelling errors and remove unused parameter (Anton Protopopov)
v8: https://lore.kernel.org/bpf/20260309140044.2652538-1-xukuohai@huaweicloud.com/
- Define void bpf_jit_blind_constants() function when CONFIG_BPF_JIT is not set
- Move indirect_target fixup for insn patching from bpf_jit_blind_constants()
to adjust_insn_aux_data()
v7: https://lore.kernel.org/bpf/20260307103949.2340104-1-xukuohai@huaweicloud.com
- Move constants blinding logic back to bpf/core.c
- Compute ip address before switch statement in x86 JIT
- Clear JIT state from error path on arm64 and loongarch
v6: https://lore.kernel.org/bpf/20260306102329.2056216-1-xukuohai@huaweicloud.com/
- Move constants blinding from JIT to verifier
- Move call to bpf_prog_select_runtime from bpf_prog_load to verifier
v5: https://lore.kernel.org/bpf/20260302102726.1126019-1-xukuohai@huaweicloud.com/
- Switch to pass env to JIT directly to get rid of copying private insn_aux_data for
each prog
v4: https://lore.kernel.org/all/20260114093914.2403982-1-xukuohai@huaweicloud.com/
- Switch to the approach proposed by Eduard, using insn_aux_data to identify indirect
jump targets, and emit ENDBR on x86
v3: https://lore.kernel.org/bpf/20251227081033.240336-1-xukuohai@huaweicloud.com/
- Get rid of unnecessary enum definition (Yonghong Song, Anton Protopopov)
v2: https://lore.kernel.org/bpf/20251223085447.139301-1-xukuohai@huaweicloud.com/
- Exclude instruction arrays not used for indirect jumps (Anton Protopopov)
v1: https://lore.kernel.org/bpf/20251127140318.3944249-1-xukuohai@huaweicloud.com/
Xu Kuohai (5):
bpf: Move constants blinding out of arch-specific JITs
bpf: Pass bpf_verifier_env to JIT
bpf: Add helper to detect indirect jump targets
bpf, x86: Emit ENDBR for indirect jump targets
bpf, arm64: Emit BTI for indirect jump target
arch/arc/net/bpf_jit_core.c | 41 ++++-------
arch/arm/net/bpf_jit_32.c | 43 +++--------
arch/arm64/net/bpf_jit_comp.c | 87 ++++++++---------------
arch/loongarch/net/bpf_jit.c | 61 +++++-----------
arch/mips/net/bpf_jit_comp.c | 22 +-----
arch/parisc/net/bpf_jit_core.c | 75 ++++++++------------
arch/powerpc/net/bpf_jit_comp.c | 70 +++++++-----------
arch/riscv/net/bpf_jit_core.c | 63 ++++++-----------
arch/s390/net/bpf_jit_comp.c | 61 ++++++----------
arch/sparc/net/bpf_jit_comp_64.c | 63 ++++++-----------
arch/x86/net/bpf_jit_comp.c | 73 ++++++-------------
arch/x86/net/bpf_jit_comp32.c | 35 ++-------
include/linux/bpf.h | 2 +
include/linux/bpf_verifier.h | 9 +--
include/linux/filter.h | 27 ++++++-
kernel/bpf/core.c | 118 +++++++++++++++++++++----------
kernel/bpf/syscall.c | 4 --
kernel/bpf/verifier.c | 79 +++++++++++++++------
18 files changed, 392 insertions(+), 541 deletions(-)
--
2.47.3
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
@ 2026-03-24 12:20 ` Xu Kuohai
2026-03-24 12:46 ` bot+bpf-ci
2026-03-24 12:20 ` [PATCH bpf-next v10 2/5] bpf: Pass bpf_verifier_env to JIT Xu Kuohai
` (3 subsequent siblings)
4 siblings, 1 reply; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
From: Xu Kuohai <xukuohai@huawei.com>
During the JIT stage, constants blinding rewrites instructions but only
rewrites the private instruction copy of the JITed subprog, leaving the
global instructions and insn_aux_data unchanged. This causes a mismatch
between subprog instructions and the global state, making it difficult
to look up the global insn_aux_data in the JIT.
To avoid this mismatch, and given that all arch-specific JITs already
support constants blinding, move it to the generic verifier code, and
switch to rewrite the global env->insnsi with the global states
adjusted, as other rewrites in the verifier do.
This removes the constants blinding calls in each JIT, which are largely
duplicated code across architectures.
Since constants blinding is only required for JIT, and there are two
entry functions for JIT, jit_subprogs() and bpf_prog_select_runtime(),
move the constants blinding invocation into the two functions.
If constants blinding fails, or if it succeeds but the subsequent JIT
compilation fails, kernel falls back to running the BPF program with
interpreter. To ensure a correct rollback, the program cloning before
instruction rewriting in the constants blinding is preserved. During
the blinding process, only the cloned instructions are patched, leaving
the original program untouched.
Since bpf_patch_insn_data() is chosen for the constants blinding in the
verifier path, and it adjusts the global auxiliary data in the verifier
state, a key question is whether this auxiliary data should be restored
when JIT fails?
Besides instructions, bpf_patch_insn_data() adjusts env->insn_aux_data,
env->subprog_info, prog->aux->poke_tab and env->insn_array_maps. env->
insn_aux_data and env->subprog_info are no longer used after JIT failure
and are freed at the end of bpf_check(). prog->aux->poke_tab is only
used by JIT. And when the JIT fails, programs using insn_array would be
rejected by bpf_insn_array_ready() function since no JITed addresses
available. This means env->insn_array_maps is only useful for JIT.
Therefore, all the auxiliary data adjusted does not need to be restored.
For classic BPF programs, constants blinding works as before since it
is still invoked from bpf_prog_select_runtime().
Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> # v8
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> # powerpc jit
Reviewed-by: Pu Lehui <pulehui@huawei.com> # riscv jit
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
---
arch/arc/net/bpf_jit_core.c | 39 ++++++-----------
arch/arm/net/bpf_jit_32.c | 41 +++---------------
arch/arm64/net/bpf_jit_comp.c | 72 +++++++++----------------------
arch/loongarch/net/bpf_jit.c | 59 ++++++++------------------
arch/mips/net/bpf_jit_comp.c | 20 +--------
arch/parisc/net/bpf_jit_core.c | 73 +++++++++++++-------------------
arch/powerpc/net/bpf_jit_comp.c | 68 +++++++++++------------------
arch/riscv/net/bpf_jit_core.c | 61 ++++++++++----------------
arch/s390/net/bpf_jit_comp.c | 59 +++++++++-----------------
arch/sparc/net/bpf_jit_comp_64.c | 61 +++++++++-----------------
arch/x86/net/bpf_jit_comp.c | 43 +++----------------
arch/x86/net/bpf_jit_comp32.c | 33 ++-------------
include/linux/filter.h | 23 +++++++++-
kernel/bpf/core.c | 66 +++++++++++++++++++++++++----
kernel/bpf/verifier.c | 53 ++++++++++++++---------
15 files changed, 301 insertions(+), 470 deletions(-)
diff --git a/arch/arc/net/bpf_jit_core.c b/arch/arc/net/bpf_jit_core.c
index 1421eeced0f5..973ceae48675 100644
--- a/arch/arc/net/bpf_jit_core.c
+++ b/arch/arc/net/bpf_jit_core.c
@@ -79,7 +79,6 @@ struct arc_jit_data {
* The JIT pertinent context that is used by different functions.
*
* prog: The current eBPF program being handled.
- * orig_prog: The original eBPF program before any possible change.
* jit: The JIT buffer and its length.
* bpf_header: The JITed program header. "jit.buf" points inside it.
* emit: If set, opcodes are written to memory; else, a dry-run.
@@ -94,12 +93,10 @@ struct arc_jit_data {
* need_extra_pass: A forecast if an "extra_pass" will occur.
* is_extra_pass: Indicates if the current pass is an extra pass.
* user_bpf_prog: True, if VM opcodes come from a real program.
- * blinded: True if "constant blinding" step returned a new "prog".
* success: Indicates if the whole JIT went OK.
*/
struct jit_context {
struct bpf_prog *prog;
- struct bpf_prog *orig_prog;
struct jit_buffer jit;
struct bpf_binary_header *bpf_header;
bool emit;
@@ -114,7 +111,6 @@ struct jit_context {
bool need_extra_pass;
bool is_extra_pass;
bool user_bpf_prog;
- bool blinded;
bool success;
};
@@ -161,13 +157,7 @@ static int jit_ctx_init(struct jit_context *ctx, struct bpf_prog *prog)
{
memset(ctx, 0, sizeof(*ctx));
- ctx->orig_prog = prog;
-
- /* If constant blinding was requested but failed, scram. */
- ctx->prog = bpf_jit_blind_constants(prog);
- if (IS_ERR(ctx->prog))
- return PTR_ERR(ctx->prog);
- ctx->blinded = (ctx->prog != ctx->orig_prog);
+ ctx->prog = prog;
/* If the verifier doesn't zero-extend, then we have to do it. */
ctx->do_zext = !ctx->prog->aux->verifier_zext;
@@ -214,14 +204,6 @@ static inline void maybe_free(struct jit_context *ctx, void **mem)
*/
static void jit_ctx_cleanup(struct jit_context *ctx)
{
- if (ctx->blinded) {
- /* if all went well, release the orig_prog. */
- if (ctx->success)
- bpf_jit_prog_release_other(ctx->prog, ctx->orig_prog);
- else
- bpf_jit_prog_release_other(ctx->orig_prog, ctx->prog);
- }
-
maybe_free(ctx, (void **)&ctx->bpf2insn);
maybe_free(ctx, (void **)&ctx->jit_data);
@@ -229,12 +211,19 @@ static void jit_ctx_cleanup(struct jit_context *ctx)
ctx->bpf2insn_valid = false;
/* Freeing "bpf_header" is enough. "jit.buf" is a sub-array of it. */
- if (!ctx->success && ctx->bpf_header) {
- bpf_jit_binary_free(ctx->bpf_header);
- ctx->bpf_header = NULL;
- ctx->jit.buf = NULL;
- ctx->jit.index = 0;
- ctx->jit.len = 0;
+ if (!ctx->success) {
+ if (ctx->bpf_header) {
+ bpf_jit_binary_free(ctx->bpf_header);
+ ctx->bpf_header = NULL;
+ ctx->jit.buf = NULL;
+ ctx->jit.index = 0;
+ ctx->jit.len = 0;
+ }
+ if (ctx->is_extra_pass) {
+ ctx->prog->bpf_func = NULL;
+ ctx->prog->jited = 0;
+ ctx->prog->jited_len = 0;
+ }
}
ctx->emit = false;
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index deeb8f292454..e6b1bb2de627 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -2144,9 +2144,7 @@ bool bpf_jit_needs_zext(void)
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
- struct bpf_prog *tmp, *orig_prog = prog;
struct bpf_binary_header *header;
- bool tmp_blinded = false;
struct jit_ctx ctx;
unsigned int tmp_idx;
unsigned int image_size;
@@ -2156,20 +2154,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
* the interpreter.
*/
if (!prog->jit_requested)
- return orig_prog;
-
- /* If constant blinding was enabled and we failed during blinding
- * then we must fall back to the interpreter. Otherwise, we save
- * the new JITed code.
- */
- tmp = bpf_jit_blind_constants(prog);
-
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
memset(&ctx, 0, sizeof(ctx));
ctx.prog = prog;
@@ -2179,10 +2164,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
* we must fall back to the interpreter
*/
ctx.offsets = kcalloc(prog->len, sizeof(int), GFP_KERNEL);
- if (ctx.offsets == NULL) {
- prog = orig_prog;
- goto out;
- }
+ if (ctx.offsets == NULL)
+ return prog;
/* 1) fake pass to find in the length of the JITed code,
* to compute ctx->offsets and other context variables
@@ -2194,10 +2177,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
* being successful in the second pass, so just fall back
* to the interpreter.
*/
- if (build_body(&ctx)) {
- prog = orig_prog;
+ if (build_body(&ctx))
goto out_off;
- }
tmp_idx = ctx.idx;
build_prologue(&ctx);
@@ -2213,10 +2194,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.idx += ctx.imm_count;
if (ctx.imm_count) {
ctx.imms = kcalloc(ctx.imm_count, sizeof(u32), GFP_KERNEL);
- if (ctx.imms == NULL) {
- prog = orig_prog;
+ if (ctx.imms == NULL)
goto out_off;
- }
}
#else
/* there's nothing about the epilogue on ARMv7 */
@@ -2238,10 +2217,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* Not able to allocate memory for the structure then
* we must fall back to the interpretation
*/
- if (header == NULL) {
- prog = orig_prog;
+ if (header == NULL)
goto out_imms;
- }
/* 2.) Actual pass to generate final JIT code */
ctx.target = (u32 *) image_ptr;
@@ -2278,16 +2255,12 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
#endif
out_off:
kfree(ctx.offsets);
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
+
return prog;
out_free:
image_ptr = NULL;
bpf_jit_binary_free(header);
- prog = orig_prog;
goto out_imms;
}
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index adf84962d579..cd5a72fff500 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -2009,14 +2009,12 @@ struct arm64_jit_data {
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
int image_size, prog_size, extable_size, extable_align, extable_offset;
- struct bpf_prog *tmp, *orig_prog = prog;
struct bpf_binary_header *header;
struct bpf_binary_header *ro_header = NULL;
struct arm64_jit_data *jit_data;
void __percpu *priv_stack_ptr = NULL;
bool was_classic = bpf_prog_was_classic(prog);
int priv_stack_alloc_sz;
- bool tmp_blinded = false;
bool extra_pass = false;
struct jit_ctx ctx;
u8 *image_ptr;
@@ -2025,26 +2023,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
int exentry_idx;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /* If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- prog = orig_prog;
- goto out;
- }
+ if (!jit_data)
+ return prog;
prog->aux->jit_data = jit_data;
}
priv_stack_ptr = prog->aux->priv_stack_ptr;
@@ -2056,10 +2041,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
priv_stack_alloc_sz = round_up(prog->aux->stack_depth, 16) +
2 * PRIV_STACK_GUARD_SZ;
priv_stack_ptr = __alloc_percpu_gfp(priv_stack_alloc_sz, 16, GFP_KERNEL);
- if (!priv_stack_ptr) {
- prog = orig_prog;
+ if (!priv_stack_ptr)
goto out_priv_stack;
- }
priv_stack_init_guard(priv_stack_ptr, priv_stack_alloc_sz);
prog->aux->priv_stack_ptr = priv_stack_ptr;
@@ -2079,10 +2062,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.prog = prog;
ctx.offset = kvzalloc_objs(int, prog->len + 1);
- if (ctx.offset == NULL) {
- prog = orig_prog;
+ if (ctx.offset == NULL)
goto out_off;
- }
ctx.user_vm_start = bpf_arena_get_user_vm_start(prog->aux->arena);
ctx.arena_vm_start = bpf_arena_get_kern_vm_start(prog->aux->arena);
@@ -2095,15 +2076,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
* BPF line info needs ctx->offset[i] to be the offset of
* instruction[i] in jited image, so build prologue first.
*/
- if (build_prologue(&ctx, was_classic)) {
- prog = orig_prog;
+ if (build_prologue(&ctx, was_classic))
goto out_off;
- }
- if (build_body(&ctx, extra_pass)) {
- prog = orig_prog;
+ if (build_body(&ctx, extra_pass))
goto out_off;
- }
ctx.epilogue_offset = ctx.idx;
build_epilogue(&ctx, was_classic);
@@ -2121,10 +2098,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ro_header = bpf_jit_binary_pack_alloc(image_size, &ro_image_ptr,
sizeof(u64), &header, &image_ptr,
jit_fill_hole);
- if (!ro_header) {
- prog = orig_prog;
+ if (!ro_header)
goto out_off;
- }
/* Pass 2: Determine jited position and result for each instruction */
@@ -2152,10 +2127,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* Dont write body instructions to memory for now */
ctx.write = false;
- if (build_body(&ctx, extra_pass)) {
- prog = orig_prog;
+ if (build_body(&ctx, extra_pass))
goto out_free_hdr;
- }
ctx.epilogue_offset = ctx.idx;
ctx.exentry_idx = exentry_idx;
@@ -2164,19 +2137,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* Pass 3: Adjust jump offset and write final image */
if (build_body(&ctx, extra_pass) ||
- WARN_ON_ONCE(ctx.idx != ctx.epilogue_offset)) {
- prog = orig_prog;
+ WARN_ON_ONCE(ctx.idx != ctx.epilogue_offset))
goto out_free_hdr;
- }
build_epilogue(&ctx, was_classic);
build_plt(&ctx);
/* Extra pass to validate JITed code. */
- if (validate_ctx(&ctx)) {
- prog = orig_prog;
+ if (validate_ctx(&ctx))
goto out_free_hdr;
- }
/* update the real prog size */
prog_size = sizeof(u32) * ctx.idx;
@@ -2193,16 +2162,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
if (extra_pass && ctx.idx > jit_data->ctx.idx) {
pr_err_once("multi-func JIT bug %d > %d\n",
ctx.idx, jit_data->ctx.idx);
- prog->bpf_func = NULL;
- prog->jited = 0;
- prog->jited_len = 0;
goto out_free_hdr;
}
if (WARN_ON(bpf_jit_binary_pack_finalize(ro_header, header))) {
- /* ro_header has been freed */
+ /* ro_header and header has been freed */
ro_header = NULL;
- prog = orig_prog;
- goto out_off;
+ header = NULL;
+ goto out_free_hdr;
}
/*
* The instructions have now been copied to the ROX region from
@@ -2245,13 +2211,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
kfree(jit_data);
prog->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
+
return prog;
out_free_hdr:
+ if (extra_pass) {
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ prog->jited_len = 0;
+ }
if (header) {
bpf_arch_text_copy(&ro_header->size, &header->size,
sizeof(header->size));
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index 9cb796e16379..fcc8c0c29fb0 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -1922,43 +1922,26 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
- bool tmp_blinded = false, extra_pass = false;
+ bool extra_pass = false;
u8 *image_ptr, *ro_image_ptr;
int image_size, prog_size, extable_size;
struct jit_ctx ctx;
struct jit_data *jit_data;
struct bpf_binary_header *header;
struct bpf_binary_header *ro_header;
- struct bpf_prog *tmp, *orig_prog = prog;
/*
* If BPF JIT was not enabled then we must fall back to
* the interpreter.
*/
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /*
- * If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter. Otherwise, we save
- * the new JITed code.
- */
- if (IS_ERR(tmp))
- return orig_prog;
-
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- prog = orig_prog;
- goto out;
- }
+ if (!jit_data)
+ return prog;
prog->aux->jit_data = jit_data;
}
if (jit_data->ctx.offset) {
@@ -1978,17 +1961,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.user_vm_start = bpf_arena_get_user_vm_start(prog->aux->arena);
ctx.offset = kvcalloc(prog->len + 1, sizeof(u32), GFP_KERNEL);
- if (ctx.offset == NULL) {
- prog = orig_prog;
+ if (ctx.offset == NULL)
goto out_offset;
- }
/* 1. Initial fake pass to compute ctx->idx and set ctx->flags */
build_prologue(&ctx);
- if (build_body(&ctx, extra_pass)) {
- prog = orig_prog;
+ if (build_body(&ctx, extra_pass))
goto out_offset;
- }
ctx.epilogue_offset = ctx.idx;
build_epilogue(&ctx);
@@ -2004,10 +1983,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* Now we know the size of the structure to make */
ro_header = bpf_jit_binary_pack_alloc(image_size, &ro_image_ptr, sizeof(u32),
&header, &image_ptr, jit_fill_hole);
- if (!ro_header) {
- prog = orig_prog;
+ if (!ro_header)
goto out_offset;
- }
/* 2. Now, the actual pass to generate final JIT code */
/*
@@ -2027,17 +2004,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.num_exentries = 0;
build_prologue(&ctx);
- if (build_body(&ctx, extra_pass)) {
- prog = orig_prog;
+ if (build_body(&ctx, extra_pass))
goto out_free;
- }
build_epilogue(&ctx);
/* 3. Extra pass to validate JITed code */
- if (validate_ctx(&ctx)) {
- prog = orig_prog;
+ if (validate_ctx(&ctx))
goto out_free;
- }
/* And we're done */
if (bpf_jit_enable > 1)
@@ -2050,9 +2023,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
goto out_free;
}
if (WARN_ON(bpf_jit_binary_pack_finalize(ro_header, header))) {
- /* ro_header has been freed */
+ /* ro_header and header have been freed */
ro_header = NULL;
- prog = orig_prog;
+ header = NULL;
goto out_free;
}
/*
@@ -2084,13 +2057,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
prog->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ? tmp : orig_prog);
-
return prog;
out_free:
+ if (extra_pass) {
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ prog->jited_len = 0;
+ }
+
if (header) {
bpf_arch_text_copy(&ro_header->size, &header->size, sizeof(header->size));
bpf_jit_binary_pack_free(ro_header, header);
diff --git a/arch/mips/net/bpf_jit_comp.c b/arch/mips/net/bpf_jit_comp.c
index e355dfca4400..d2b6c955f18e 100644
--- a/arch/mips/net/bpf_jit_comp.c
+++ b/arch/mips/net/bpf_jit_comp.c
@@ -911,10 +911,8 @@ bool bpf_jit_needs_zext(void)
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
- struct bpf_prog *tmp, *orig_prog = prog;
struct bpf_binary_header *header = NULL;
struct jit_context ctx;
- bool tmp_blinded = false;
unsigned int tmp_idx;
unsigned int image_size;
u8 *image_ptr;
@@ -925,19 +923,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
* the interpreter.
*/
if (!prog->jit_requested)
- return orig_prog;
- /*
- * If constant blinding was enabled and we failed during blinding
- * then we must fall back to the interpreter. Otherwise, we save
- * the new JITed code.
- */
- tmp = bpf_jit_blind_constants(prog);
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
memset(&ctx, 0, sizeof(ctx));
ctx.program = prog;
@@ -1025,14 +1011,10 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
prog->jited_len = image_size;
out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
kfree(ctx.descriptors);
return prog;
out_err:
- prog = orig_prog;
if (header)
bpf_jit_binary_free(header);
goto out;
diff --git a/arch/parisc/net/bpf_jit_core.c b/arch/parisc/net/bpf_jit_core.c
index a5eb6b51e27a..35dca372b5df 100644
--- a/arch/parisc/net/bpf_jit_core.c
+++ b/arch/parisc/net/bpf_jit_core.c
@@ -44,30 +44,19 @@ bool bpf_jit_needs_zext(void)
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
unsigned int prog_size = 0, extable_size = 0;
- bool tmp_blinded = false, extra_pass = false;
- struct bpf_prog *tmp, *orig_prog = prog;
+ bool extra_pass = false;
int pass = 0, prev_ninsns = 0, prologue_len, i;
struct hppa_jit_data *jit_data;
struct hppa_jit_context *ctx;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- prog = orig_prog;
- goto out;
- }
+ if (!jit_data)
+ return prog;
prog->aux->jit_data = jit_data;
}
@@ -81,10 +70,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx->prog = prog;
ctx->offset = kzalloc_objs(int, prog->len);
- if (!ctx->offset) {
- prog = orig_prog;
- goto out_offset;
- }
+ if (!ctx->offset)
+ goto out_err;
for (i = 0; i < prog->len; i++) {
prev_ninsns += 20;
ctx->offset[i] = prev_ninsns;
@@ -93,10 +80,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
for (i = 0; i < NR_JIT_ITERATIONS; i++) {
pass++;
ctx->ninsns = 0;
- if (build_body(ctx, extra_pass, ctx->offset)) {
- prog = orig_prog;
- goto out_offset;
- }
+ if (build_body(ctx, extra_pass, ctx->offset))
+ goto out_err;
ctx->body_len = ctx->ninsns;
bpf_jit_build_prologue(ctx);
ctx->prologue_len = ctx->ninsns - ctx->body_len;
@@ -116,10 +101,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
&jit_data->image,
sizeof(long),
bpf_fill_ill_insns);
- if (!jit_data->header) {
- prog = orig_prog;
- goto out_offset;
- }
+ if (!jit_data->header)
+ goto out_err;
ctx->insns = (u32 *)jit_data->image;
/*
@@ -134,8 +117,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
pr_err("bpf-jit: image did not converge in <%d passes!\n", i);
if (jit_data->header)
bpf_jit_binary_free(jit_data->header);
- prog = orig_prog;
- goto out_offset;
+ goto out_err;
}
if (extable_size)
@@ -148,8 +130,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
bpf_jit_build_prologue(ctx);
if (build_body(ctx, extra_pass, NULL)) {
bpf_jit_binary_free(jit_data->header);
- prog = orig_prog;
- goto out_offset;
+ goto out_err;
}
bpf_jit_build_epilogue(ctx);
@@ -160,20 +141,19 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{ extern int machine_restart(char *); machine_restart(""); }
}
+ if (!prog->is_func || extra_pass) {
+ if (bpf_jit_binary_lock_ro(jit_data->header)) {
+ bpf_jit_binary_free(jit_data->header);
+ goto out_err;
+ }
+ bpf_flush_icache(jit_data->header, ctx->insns + ctx->ninsns);
+ }
+
prog->bpf_func = (void *)ctx->insns;
prog->jited = 1;
prog->jited_len = prog_size;
- bpf_flush_icache(jit_data->header, ctx->insns + ctx->ninsns);
-
if (!prog->is_func || extra_pass) {
- if (bpf_jit_binary_lock_ro(jit_data->header)) {
- bpf_jit_binary_free(jit_data->header);
- prog->bpf_func = NULL;
- prog->jited = 0;
- prog->jited_len = 0;
- goto out_offset;
- }
prologue_len = ctx->epilogue_offset - ctx->body_len;
for (i = 0; i < prog->len; i++)
ctx->offset[i] += prologue_len;
@@ -183,14 +163,19 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
kfree(jit_data);
prog->aux->jit_data = NULL;
}
-out:
+
if (HPPA_JIT_REBOOT)
{ extern int machine_restart(char *); machine_restart(""); }
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
return prog;
+
+out_err:
+ if (extra_pass) {
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ prog->jited_len = 0;
+ }
+ goto out_offset;
}
u64 hppa_div64(u64 div, u64 divisor)
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index a62a9a92b7b5..711028bebea3 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -142,9 +142,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
int flen;
struct bpf_binary_header *fhdr = NULL;
struct bpf_binary_header *hdr = NULL;
- struct bpf_prog *org_fp = fp;
- struct bpf_prog *tmp_fp;
- bool bpf_blinded = false;
bool extra_pass = false;
u8 *fimage = NULL;
u32 *fcode_base;
@@ -152,24 +149,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
u32 fixup_len;
if (!fp->jit_requested)
- return org_fp;
-
- tmp_fp = bpf_jit_blind_constants(org_fp);
- if (IS_ERR(tmp_fp))
- return org_fp;
-
- if (tmp_fp != org_fp) {
- bpf_blinded = true;
- fp = tmp_fp;
- }
+ return fp;
jit_data = fp->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- fp = org_fp;
- goto out;
- }
+ if (!jit_data)
+ return fp;
fp->aux->jit_data = jit_data;
}
@@ -194,10 +180,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
}
addrs = kcalloc(flen + 1, sizeof(*addrs), GFP_KERNEL);
- if (addrs == NULL) {
- fp = org_fp;
- goto out_addrs;
- }
+ if (addrs == NULL)
+ goto out_err;
memset(&cgctx, 0, sizeof(struct codegen_context));
bpf_jit_init_reg_mapping(&cgctx);
@@ -211,11 +195,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
cgctx.exception_cb = fp->aux->exception_cb;
/* Scouting faux-generate pass 0 */
- if (bpf_jit_build_body(fp, NULL, NULL, &cgctx, addrs, 0, false)) {
+ if (bpf_jit_build_body(fp, NULL, NULL, &cgctx, addrs, 0, false))
/* We hit something illegal or unsupported. */
- fp = org_fp;
- goto out_addrs;
- }
+ goto out_err;
/*
* If we have seen a tail call, we need a second pass.
@@ -226,10 +208,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
*/
if (cgctx.seen & SEEN_TAILCALL || !is_offset_in_branch_range((long)cgctx.idx * 4)) {
cgctx.idx = 0;
- if (bpf_jit_build_body(fp, NULL, NULL, &cgctx, addrs, 0, false)) {
- fp = org_fp;
- goto out_addrs;
- }
+ if (bpf_jit_build_body(fp, NULL, NULL, &cgctx, addrs, 0, false))
+ goto out_err;
}
bpf_jit_realloc_regs(&cgctx);
@@ -250,10 +230,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
fhdr = bpf_jit_binary_pack_alloc(alloclen, &fimage, 4, &hdr, &image,
bpf_jit_fill_ill_insns);
- if (!fhdr) {
- fp = org_fp;
- goto out_addrs;
- }
+ if (!fhdr)
+ goto out_err;
if (extable_len)
fp->aux->extable = (void *)fimage + FUNCTION_DESCR_SIZE + proglen + fixup_len;
@@ -272,8 +250,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
extra_pass)) {
bpf_arch_text_copy(&fhdr->size, &hdr->size, sizeof(hdr->size));
bpf_jit_binary_pack_free(fhdr, hdr);
- fp = org_fp;
- goto out_addrs;
+ goto out_err;
}
bpf_jit_build_epilogue(code_base, &cgctx);
@@ -295,15 +272,16 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
((u64 *)image)[1] = local_paca->kernel_toc;
#endif
+ if (!fp->is_func || extra_pass) {
+ if (bpf_jit_binary_pack_finalize(fhdr, hdr))
+ goto out_err;
+ }
+
fp->bpf_func = (void *)fimage;
fp->jited = 1;
fp->jited_len = cgctx.idx * 4 + FUNCTION_DESCR_SIZE;
if (!fp->is_func || extra_pass) {
- if (bpf_jit_binary_pack_finalize(fhdr, hdr)) {
- fp = org_fp;
- goto out_addrs;
- }
bpf_prog_fill_jited_linfo(fp, addrs);
out_addrs:
kfree(addrs);
@@ -318,11 +296,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
jit_data->hdr = hdr;
}
-out:
- if (bpf_blinded)
- bpf_jit_prog_release_other(fp, fp == org_fp ? tmp_fp : org_fp);
-
return fp;
+
+out_err:
+ if (extra_pass) {
+ fp->bpf_func = NULL;
+ fp->jited = 0;
+ fp->jited_len = 0;
+ }
+ goto out_addrs;
}
/*
diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c
index b3581e926436..527baa50dc68 100644
--- a/arch/riscv/net/bpf_jit_core.c
+++ b/arch/riscv/net/bpf_jit_core.c
@@ -44,29 +44,19 @@ bool bpf_jit_needs_zext(void)
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
unsigned int prog_size = 0, extable_size = 0;
- bool tmp_blinded = false, extra_pass = false;
- struct bpf_prog *tmp, *orig_prog = prog;
+ bool extra_pass = false;
int pass = 0, prev_ninsns = 0, i;
struct rv_jit_data *jit_data;
struct rv_jit_context *ctx;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
if (!jit_data) {
- prog = orig_prog;
- goto out;
+ return prog;
}
prog->aux->jit_data = jit_data;
}
@@ -83,15 +73,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx->user_vm_start = bpf_arena_get_user_vm_start(prog->aux->arena);
ctx->prog = prog;
ctx->offset = kzalloc_objs(int, prog->len);
- if (!ctx->offset) {
- prog = orig_prog;
+ if (!ctx->offset)
goto out_offset;
- }
- if (build_body(ctx, extra_pass, NULL)) {
- prog = orig_prog;
+ if (build_body(ctx, extra_pass, NULL))
goto out_offset;
- }
for (i = 0; i < prog->len; i++) {
prev_ninsns += 32;
@@ -105,10 +91,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
bpf_jit_build_prologue(ctx, bpf_is_subprog(prog));
ctx->prologue_len = ctx->ninsns;
- if (build_body(ctx, extra_pass, ctx->offset)) {
- prog = orig_prog;
+ if (build_body(ctx, extra_pass, ctx->offset))
goto out_offset;
- }
ctx->epilogue_offset = ctx->ninsns;
bpf_jit_build_epilogue(ctx);
@@ -126,10 +110,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
&jit_data->ro_image, sizeof(u32),
&jit_data->header, &jit_data->image,
bpf_fill_ill_insns);
- if (!jit_data->ro_header) {
- prog = orig_prog;
+ if (!jit_data->ro_header)
goto out_offset;
- }
/*
* Use the image(RW) for writing the JITed instructions. But also save
@@ -150,7 +132,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
if (i == NR_JIT_ITERATIONS) {
pr_err("bpf-jit: image did not converge in <%d passes!\n", i);
- prog = orig_prog;
goto out_free_hdr;
}
@@ -163,26 +144,27 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx->nexentries = 0;
bpf_jit_build_prologue(ctx, bpf_is_subprog(prog));
- if (build_body(ctx, extra_pass, NULL)) {
- prog = orig_prog;
+ if (build_body(ctx, extra_pass, NULL))
goto out_free_hdr;
- }
bpf_jit_build_epilogue(ctx);
if (bpf_jit_enable > 1)
bpf_jit_dump(prog->len, prog_size, pass, ctx->insns);
- prog->bpf_func = (void *)ctx->ro_insns + cfi_get_offset();
- prog->jited = 1;
- prog->jited_len = prog_size - cfi_get_offset();
-
if (!prog->is_func || extra_pass) {
if (WARN_ON(bpf_jit_binary_pack_finalize(jit_data->ro_header, jit_data->header))) {
/* ro_header has been freed */
jit_data->ro_header = NULL;
- prog = orig_prog;
- goto out_offset;
+ jit_data->header = NULL;
+ goto out_free_hdr;
}
+ }
+
+ prog->bpf_func = (void *)ctx->ro_insns + cfi_get_offset();
+ prog->jited = 1;
+ prog->jited_len = prog_size - cfi_get_offset();
+
+ if (!prog->is_func || extra_pass) {
/*
* The instructions have now been copied to the ROX region from
* where they will execute.
@@ -198,14 +180,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
kfree(jit_data);
prog->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
return prog;
out_free_hdr:
+ if (extra_pass) {
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ prog->jited_len = 0;
+ }
if (jit_data->header) {
bpf_arch_text_copy(&jit_data->ro_header->size, &jit_data->header->size,
sizeof(jit_data->header->size));
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index d08d159b6319..2dfc279b1be2 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2314,36 +2314,20 @@ static struct bpf_binary_header *bpf_jit_alloc(struct bpf_jit *jit,
*/
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
{
- struct bpf_prog *tmp, *orig_fp = fp;
struct bpf_binary_header *header;
struct s390_jit_data *jit_data;
- bool tmp_blinded = false;
bool extra_pass = false;
struct bpf_jit jit;
int pass;
if (!fp->jit_requested)
- return orig_fp;
-
- tmp = bpf_jit_blind_constants(fp);
- /*
- * If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_fp;
- if (tmp != fp) {
- tmp_blinded = true;
- fp = tmp;
- }
+ return fp;
jit_data = fp->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- fp = orig_fp;
- goto out;
- }
+ if (!jit_data)
+ return fp;
fp->aux->jit_data = jit_data;
}
if (jit_data->ctx.addrs) {
@@ -2356,34 +2340,27 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
memset(&jit, 0, sizeof(jit));
jit.addrs = kvcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL);
- if (jit.addrs == NULL) {
- fp = orig_fp;
- goto free_addrs;
- }
+ if (jit.addrs == NULL)
+ goto out_err;
/*
* Three initial passes:
* - 1/2: Determine clobbered registers
* - 3: Calculate program size and addrs array
*/
for (pass = 1; pass <= 3; pass++) {
- if (bpf_jit_prog(&jit, fp, extra_pass)) {
- fp = orig_fp;
- goto free_addrs;
- }
+ if (bpf_jit_prog(&jit, fp, extra_pass))
+ goto out_err;
}
/*
* Final pass: Allocate and generate program
*/
header = bpf_jit_alloc(&jit, fp);
- if (!header) {
- fp = orig_fp;
- goto free_addrs;
- }
+ if (!header)
+ goto out_err;
skip_init_ctx:
if (bpf_jit_prog(&jit, fp, extra_pass)) {
bpf_jit_binary_free(header);
- fp = orig_fp;
- goto free_addrs;
+ goto out_err;
}
if (bpf_jit_enable > 1) {
bpf_jit_dump(fp->len, jit.size, pass, jit.prg_buf);
@@ -2392,8 +2369,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
if (!fp->is_func || extra_pass) {
if (bpf_jit_binary_lock_ro(header)) {
bpf_jit_binary_free(header);
- fp = orig_fp;
- goto free_addrs;
+ goto out_err;
}
} else {
jit_data->header = header;
@@ -2411,11 +2387,16 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
kfree(jit_data);
fp->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(fp, fp == orig_fp ?
- tmp : orig_fp);
+
return fp;
+
+out_err:
+ if (extra_pass) {
+ fp->bpf_func = NULL;
+ fp->jited = 0;
+ fp->jited_len = 0;
+ }
+ goto free_addrs;
}
bool bpf_jit_supports_kfunc_call(void)
diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c
index b23d1c645ae5..e83e29137566 100644
--- a/arch/sparc/net/bpf_jit_comp_64.c
+++ b/arch/sparc/net/bpf_jit_comp_64.c
@@ -1479,37 +1479,22 @@ struct sparc64_jit_data {
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
- struct bpf_prog *tmp, *orig_prog = prog;
struct sparc64_jit_data *jit_data;
struct bpf_binary_header *header;
u32 prev_image_size, image_size;
- bool tmp_blinded = false;
bool extra_pass = false;
struct jit_ctx ctx;
u8 *image_ptr;
int pass, i;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /* If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- prog = orig_prog;
- goto out;
- }
+ if (!jit_data)
+ return prog;
prog->aux->jit_data = jit_data;
}
if (jit_data->ctx.offset) {
@@ -1527,10 +1512,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.prog = prog;
ctx.offset = kmalloc_array(prog->len, sizeof(unsigned int), GFP_KERNEL);
- if (ctx.offset == NULL) {
- prog = orig_prog;
- goto out_off;
- }
+ if (ctx.offset == NULL)
+ goto out_err;
/* Longest sequence emitted is for bswap32, 12 instructions. Pre-cook
* the offset array so that we converge faster.
@@ -1543,10 +1526,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
ctx.idx = 0;
build_prologue(&ctx);
- if (build_body(&ctx)) {
- prog = orig_prog;
- goto out_off;
- }
+ if (build_body(&ctx))
+ goto out_err;
build_epilogue(&ctx);
if (bpf_jit_enable > 1)
@@ -1569,10 +1550,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
image_size = sizeof(u32) * ctx.idx;
header = bpf_jit_binary_alloc(image_size, &image_ptr,
sizeof(u32), jit_fill_hole);
- if (header == NULL) {
- prog = orig_prog;
- goto out_off;
- }
+ if (header == NULL)
+ goto out_err;
ctx.image = (u32 *)image_ptr;
skip_init_ctx:
@@ -1582,8 +1561,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
if (build_body(&ctx)) {
bpf_jit_binary_free(header);
- prog = orig_prog;
- goto out_off;
+ goto out_err;
}
build_epilogue(&ctx);
@@ -1592,8 +1570,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
pr_err("bpf_jit: Failed to converge, prev_size=%u size=%d\n",
prev_image_size, ctx.idx * 4);
bpf_jit_binary_free(header);
- prog = orig_prog;
- goto out_off;
+ goto out_err;
}
if (bpf_jit_enable > 1)
@@ -1604,8 +1581,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
if (!prog->is_func || extra_pass) {
if (bpf_jit_binary_lock_ro(header)) {
bpf_jit_binary_free(header);
- prog = orig_prog;
- goto out_off;
+ goto out_err;
}
} else {
jit_data->ctx = ctx;
@@ -1624,9 +1600,14 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
kfree(jit_data);
prog->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
+
return prog;
+
+out_err:
+ if (extra_pass) {
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ prog->jited_len = 0;
+ }
+ goto out_off;
}
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index e9b78040d703..77d00a8dec87 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -3717,13 +3717,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
struct bpf_binary_header *rw_header = NULL;
struct bpf_binary_header *header = NULL;
- struct bpf_prog *tmp, *orig_prog = prog;
void __percpu *priv_stack_ptr = NULL;
struct x64_jit_data *jit_data;
int priv_stack_alloc_sz;
int proglen, oldproglen = 0;
struct jit_context ctx = {};
- bool tmp_blinded = false;
bool extra_pass = false;
bool padding = false;
u8 *rw_image = NULL;
@@ -3733,27 +3731,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
int i;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /*
- * If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc_obj(*jit_data);
- if (!jit_data) {
- prog = orig_prog;
- goto out;
- }
+ if (!jit_data)
+ return prog;
prog->aux->jit_data = jit_data;
}
priv_stack_ptr = prog->aux->priv_stack_ptr;
@@ -3765,10 +3749,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
priv_stack_alloc_sz = round_up(prog->aux->stack_depth, 8) +
2 * PRIV_STACK_GUARD_SZ;
priv_stack_ptr = __alloc_percpu_gfp(priv_stack_alloc_sz, 8, GFP_KERNEL);
- if (!priv_stack_ptr) {
- prog = orig_prog;
+ if (!priv_stack_ptr)
goto out_priv_stack;
- }
priv_stack_init_guard(priv_stack_ptr, priv_stack_alloc_sz);
prog->aux->priv_stack_ptr = priv_stack_ptr;
@@ -3786,10 +3768,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
goto skip_init_addrs;
}
addrs = kvmalloc_objs(*addrs, prog->len + 1);
- if (!addrs) {
- prog = orig_prog;
+ if (!addrs)
goto out_addrs;
- }
/*
* Before first pass, make a rough estimation of addrs[]
@@ -3820,8 +3800,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
sizeof(rw_header->size));
bpf_jit_binary_pack_free(header, rw_header);
}
- /* Fall back to interpreter mode */
- prog = orig_prog;
if (extra_pass) {
prog->bpf_func = NULL;
prog->jited = 0;
@@ -3852,10 +3830,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
header = bpf_jit_binary_pack_alloc(roundup(proglen, align) + extable_size,
&image, align, &rw_header, &rw_image,
jit_fill_hole);
- if (!header) {
- prog = orig_prog;
+ if (!header)
goto out_addrs;
- }
prog->aux->extable = (void *) image + roundup(proglen, align);
}
oldproglen = proglen;
@@ -3908,8 +3884,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
prog->bpf_func = (void *)image + cfi_get_offset();
prog->jited = 1;
prog->jited_len = proglen - cfi_get_offset();
- } else {
- prog = orig_prog;
}
if (!image || !prog->is_func || extra_pass) {
@@ -3925,10 +3899,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
kfree(jit_data);
prog->aux->jit_data = NULL;
}
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
+
return prog;
}
diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
index dda423025c3d..5f259577614a 100644
--- a/arch/x86/net/bpf_jit_comp32.c
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -2521,35 +2521,19 @@ bool bpf_jit_needs_zext(void)
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
struct bpf_binary_header *header = NULL;
- struct bpf_prog *tmp, *orig_prog = prog;
int proglen, oldproglen = 0;
struct jit_context ctx = {};
- bool tmp_blinded = false;
u8 *image = NULL;
int *addrs;
int pass;
int i;
if (!prog->jit_requested)
- return orig_prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /*
- * If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
+ return prog;
addrs = kmalloc_objs(*addrs, prog->len);
- if (!addrs) {
- prog = orig_prog;
- goto out;
- }
+ if (!addrs)
+ return prog;
/*
* Before first pass, make a rough estimation of addrs[]
@@ -2574,7 +2558,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
image = NULL;
if (header)
bpf_jit_binary_free(header);
- prog = orig_prog;
goto out_addrs;
}
if (image) {
@@ -2588,10 +2571,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
if (proglen == oldproglen) {
header = bpf_jit_binary_alloc(proglen, &image,
1, jit_fill_hole);
- if (!header) {
- prog = orig_prog;
+ if (!header)
goto out_addrs;
- }
}
oldproglen = proglen;
cond_resched();
@@ -2604,16 +2585,10 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
prog->bpf_func = (void *)image;
prog->jited = 1;
prog->jited_len = proglen;
- } else {
- prog = orig_prog;
}
out_addrs:
kfree(addrs);
-out:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
return prog;
}
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 44d7ae95ddbc..d8c97f463e0f 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1184,6 +1184,18 @@ static inline bool bpf_dump_raw_ok(const struct cred *cred)
struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
const struct bpf_insn *patch, u32 len);
+
+#ifdef CONFIG_BPF_SYSCALL
+struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off,
+ const struct bpf_insn *patch, u32 len);
+#else
+static inline struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off,
+ const struct bpf_insn *patch, u32 len)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
+#endif
+
int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
static inline bool xdp_return_frame_no_direct(void)
@@ -1310,7 +1322,7 @@ int bpf_jit_get_func_addr(const struct bpf_prog *prog,
const char *bpf_jit_get_prog_name(struct bpf_prog *prog);
-struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
+struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog);
void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
@@ -1451,6 +1463,15 @@ static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
{
}
+static inline
+struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
+{
+ return prog;
+}
+
+static inline void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other)
+{
+}
#endif /* CONFIG_BPF_JIT */
void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 67eb12b637a5..8f52f4b6c3af 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1507,13 +1507,16 @@ static void adjust_insn_arrays(struct bpf_prog *prog, u32 off, u32 len)
#endif
}
-struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
+struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_insn insn_buff[16], aux[2];
struct bpf_prog *clone, *tmp;
int insn_delta, insn_cnt;
struct bpf_insn *insn;
- int i, rewritten;
+ int i, rewritten, subprog_start;
+
+ if (env)
+ prog = env->prog;
if (!prog->blinding_requested || prog->blinded)
return prog;
@@ -1522,8 +1525,13 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
if (!clone)
return ERR_PTR(-ENOMEM);
+ /* make sure bpf_patch_insn_data() patches the correct prog */
+ if (env)
+ env->prog = clone;
+
insn_cnt = clone->len;
insn = clone->insnsi;
+ subprog_start = prog->aux->subprog_start;
for (i = 0; i < insn_cnt; i++, insn++) {
if (bpf_pseudo_func(insn)) {
@@ -1549,21 +1557,34 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
if (!rewritten)
continue;
- tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
- if (IS_ERR(tmp)) {
+ if (env)
+ tmp = bpf_patch_insn_data(env, subprog_start + i, insn_buff, rewritten);
+ else
+ tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
+
+ if (IS_ERR_OR_NULL(tmp)) {
+ /* restore the original prog */
+ if (env)
+ env->prog = prog;
/* Patching may have repointed aux->prog during
* realloc from the original one, so we need to
* fix it up here on error.
*/
bpf_jit_prog_release_other(prog, clone);
- return tmp;
+ return IS_ERR(tmp) ? tmp : ERR_PTR(-ENOMEM);
}
clone = tmp;
insn_delta = rewritten - 1;
- /* Instructions arrays must be updated using absolute xlated offsets */
- adjust_insn_arrays(clone, prog->aux->subprog_start + i, rewritten);
+ if (env)
+ env->prog = clone;
+ else
+ /* Instructions arrays must be updated using absolute xlated offsets.
+ * The arrays have already been adjusted by bpf_patch_insn_data() when
+ * env is not NULL.
+ */
+ adjust_insn_arrays(clone, subprog_start + i, rewritten);
/* Walk new program and skip insns we just inserted. */
insn = clone->insnsi + i + insn_delta;
@@ -2532,6 +2553,35 @@ static bool bpf_prog_select_interpreter(struct bpf_prog *fp)
return select_interpreter;
}
+static struct bpf_prog *bpf_prog_jit_compile(struct bpf_prog *prog)
+{
+#ifdef CONFIG_BPF_JIT
+ bool blinded = false;
+ struct bpf_prog *orig_prog = prog;
+
+ prog = bpf_jit_blind_constants(NULL, orig_prog);
+ /* If blinding was requested and we failed during blinding, we must fall
+ * back to the interpreter.
+ */
+ if (IS_ERR(prog))
+ return orig_prog;
+
+ if (prog != orig_prog)
+ blinded = true;
+
+ prog = bpf_int_jit_compile(prog);
+ if (blinded) {
+ if (!prog->jited) {
+ bpf_jit_prog_release_other(orig_prog, prog);
+ prog = orig_prog;
+ } else {
+ bpf_jit_prog_release_other(prog, orig_prog);
+ }
+ }
+#endif
+ return prog;
+}
+
/**
* bpf_prog_select_runtime - select exec runtime for BPF program
* @fp: bpf_prog populated with BPF program
@@ -2571,7 +2621,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
if (*err)
return fp;
- fp = bpf_int_jit_compile(fp);
+ fp = bpf_prog_jit_compile(fp);
bpf_prog_jit_attempt_done(fp);
if (!fp->jited && jit_needed) {
*err = -ENOTSUPP;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index cd008b146ee5..1b2b99f2d859 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -22105,8 +22105,8 @@ static void adjust_poke_descs(struct bpf_prog *prog, u32 off, u32 len)
}
}
-static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off,
- const struct bpf_insn *patch, u32 len)
+struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off,
+ const struct bpf_insn *patch, u32 len)
{
struct bpf_prog *new_prog;
struct bpf_insn_aux_data *new_data = NULL;
@@ -22875,17 +22875,23 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
static int jit_subprogs(struct bpf_verifier_env *env)
{
- struct bpf_prog *prog = env->prog, **func, *tmp;
+ struct bpf_prog *orig_prog = env->prog, *prog, **func, *tmp;
int i, j, subprog_start, subprog_end = 0, len, subprog;
struct bpf_map *map_ptr;
struct bpf_insn *insn;
void *old_bpf_func;
int err, num_exentries;
- int old_len, subprog_start_adjustment = 0;
+ bool blinded = false;
if (env->subprog_cnt <= 1)
return 0;
+ prog = bpf_jit_blind_constants(env, NULL);
+ if (IS_ERR(prog))
+ return -ENOMEM;
+ if (prog != orig_prog)
+ blinded = true;
+
for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
if (!bpf_pseudo_func(insn) && !bpf_pseudo_call(insn))
continue;
@@ -22896,8 +22902,13 @@ static int jit_subprogs(struct bpf_verifier_env *env)
*/
subprog = find_subprog(env, i + insn->imm + 1);
if (verifier_bug_if(subprog < 0, env, "No program to jit at insn %d",
- i + insn->imm + 1))
+ i + insn->imm + 1)) {
+ if (blinded) {
+ bpf_jit_prog_release_other(orig_prog, prog);
+ env->prog = orig_prog;
+ }
return -EFAULT;
+ }
/* temporarily remember subprog id inside insn instead of
* aux_data, since next loop will split up all insns into funcs
*/
@@ -22953,10 +22964,11 @@ static int jit_subprogs(struct bpf_verifier_env *env)
goto out_free;
func[i]->is_func = 1;
func[i]->sleepable = prog->sleepable;
+ func[i]->blinded = prog->blinded;
func[i]->aux->func_idx = i;
/* Below members will be freed only at prog->aux */
func[i]->aux->btf = prog->aux->btf;
- func[i]->aux->subprog_start = subprog_start + subprog_start_adjustment;
+ func[i]->aux->subprog_start = subprog_start;
func[i]->aux->func_info = prog->aux->func_info;
func[i]->aux->func_info_cnt = prog->aux->func_info_cnt;
func[i]->aux->poke_tab = prog->aux->poke_tab;
@@ -23012,15 +23024,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->might_sleep = env->subprog_info[i].might_sleep;
if (!i)
func[i]->aux->exception_boundary = env->seen_exception;
-
- /*
- * To properly pass the absolute subprog start to jit
- * all instruction adjustments should be accumulated
- */
- old_len = func[i]->len;
func[i] = bpf_int_jit_compile(func[i]);
- subprog_start_adjustment += func[i]->len - old_len;
-
if (!func[i]->jited) {
err = -ENOTSUPP;
goto out_free;
@@ -23124,6 +23128,10 @@ static int jit_subprogs(struct bpf_verifier_env *env)
prog->aux->bpf_exception_cb = (void *)func[env->exception_callback_subprog]->bpf_func;
prog->aux->exception_boundary = func[0]->aux->exception_boundary;
bpf_prog_jit_attempt_done(prog);
+
+ if (blinded)
+ bpf_jit_prog_release_other(prog, orig_prog);
+
return 0;
out_free:
/* We failed JIT'ing, so at this point we need to unregister poke
@@ -23146,14 +23154,21 @@ static int jit_subprogs(struct bpf_verifier_env *env)
}
kfree(func);
out_undo_insn:
+ if (blinded) {
+ bpf_jit_prog_release_other(orig_prog, prog);
+ env->prog = prog = orig_prog;
+ }
/* cleanup main prog to be interpreted */
prog->jit_requested = 0;
prog->blinding_requested = 0;
- for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
- if (!bpf_pseudo_call(insn))
- continue;
- insn->off = 0;
- insn->imm = env->insn_aux_data[i].call_imm;
+ /* we already rolled back to the clean orig_prog when blinded is true */
+ if (!blinded) {
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ if (!bpf_pseudo_call(insn))
+ continue;
+ insn->off = 0;
+ insn->imm = env->insn_aux_data[i].call_imm;
+ }
}
bpf_prog_jit_attempt_done(prog);
return err;
--
2.47.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH bpf-next v10 2/5] bpf: Pass bpf_verifier_env to JIT
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs Xu Kuohai
@ 2026-03-24 12:20 ` Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 3/5] bpf: Add helper to detect indirect jump targets Xu Kuohai
` (2 subsequent siblings)
4 siblings, 0 replies; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
From: Xu Kuohai <xukuohai@huawei.com>
Pass bpf_verifier_env to bpf_int_jit_compile(). The follow-up patch will
use env->insn_aux_data in the JIT stage to detect indirect jump targets.
Since bpf_prog_select_runtime() can be called by cbpf and lib/test_bpf.c
code without verifier, introduce helper __bpf_prog_select_runtime()
to accept the env parameter.
Remove the call to bpf_prog_select_runtime() in bpf_prog_load(), and
switch to call __bpf_prog_select_runtime() in the verifier, with env
variable passed. The original bpf_prog_select_runtime() is preserved for
cbpf and lib/test_bpf.c, where env is NULL.
Now all constants blinding calls are moved into the verifier, except
the cbpf and lib/test_bpf.c cases. The instructions arrays are adjusted
by bpf_patch_insn_data() function for normal cases, so there is no need
to call adjust_insn_arrays() in bpf_jit_blind_constants(). Remove it.
Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
---
arch/arc/net/bpf_jit_core.c | 2 +-
arch/arm/net/bpf_jit_32.c | 2 +-
arch/arm64/net/bpf_jit_comp.c | 2 +-
arch/loongarch/net/bpf_jit.c | 2 +-
arch/mips/net/bpf_jit_comp.c | 2 +-
arch/parisc/net/bpf_jit_core.c | 2 +-
arch/powerpc/net/bpf_jit_comp.c | 2 +-
arch/riscv/net/bpf_jit_core.c | 2 +-
arch/s390/net/bpf_jit_comp.c | 2 +-
arch/sparc/net/bpf_jit_comp_64.c | 2 +-
arch/x86/net/bpf_jit_comp.c | 2 +-
arch/x86/net/bpf_jit_comp32.c | 2 +-
include/linux/filter.h | 4 +-
kernel/bpf/core.c | 63 ++++++++++++--------------------
kernel/bpf/syscall.c | 4 --
kernel/bpf/verifier.c | 8 +++-
16 files changed, 44 insertions(+), 59 deletions(-)
diff --git a/arch/arc/net/bpf_jit_core.c b/arch/arc/net/bpf_jit_core.c
index 973ceae48675..639a2736f029 100644
--- a/arch/arc/net/bpf_jit_core.c
+++ b/arch/arc/net/bpf_jit_core.c
@@ -1400,7 +1400,7 @@ static struct bpf_prog *do_extra_pass(struct bpf_prog *prog)
* (re)locations involved that their addresses are not known
* during the first run.
*/
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
vm_dump(prog);
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index e6b1bb2de627..1628b6fc70a4 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -2142,7 +2142,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_binary_header *header;
struct jit_ctx ctx;
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index cd5a72fff500..7212ec89dfe3 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -2006,7 +2006,7 @@ struct arm64_jit_data {
struct jit_ctx ctx;
};
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
int image_size, prog_size, extable_size, extable_align, extable_offset;
struct bpf_binary_header *header;
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index fcc8c0c29fb0..5149ce4cef7e 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -1920,7 +1920,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
return ret < 0 ? ret : ret * LOONGARCH_INSN_SIZE;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
bool extra_pass = false;
u8 *image_ptr, *ro_image_ptr;
diff --git a/arch/mips/net/bpf_jit_comp.c b/arch/mips/net/bpf_jit_comp.c
index d2b6c955f18e..6ee4abe6a1f7 100644
--- a/arch/mips/net/bpf_jit_comp.c
+++ b/arch/mips/net/bpf_jit_comp.c
@@ -909,7 +909,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_binary_header *header = NULL;
struct jit_context ctx;
diff --git a/arch/parisc/net/bpf_jit_core.c b/arch/parisc/net/bpf_jit_core.c
index 35dca372b5df..172770132440 100644
--- a/arch/parisc/net/bpf_jit_core.c
+++ b/arch/parisc/net/bpf_jit_core.c
@@ -41,7 +41,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
unsigned int prog_size = 0, extable_size = 0;
bool extra_pass = false;
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 711028bebea3..27fecb4cc063 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -129,7 +129,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *fp)
{
u32 proglen;
u32 alloclen;
diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c
index 527baa50dc68..768ac686b359 100644
--- a/arch/riscv/net/bpf_jit_core.c
+++ b/arch/riscv/net/bpf_jit_core.c
@@ -41,7 +41,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
unsigned int prog_size = 0, extable_size = 0;
bool extra_pass = false;
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 2dfc279b1be2..94128fe6be23 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2312,7 +2312,7 @@ static struct bpf_binary_header *bpf_jit_alloc(struct bpf_jit *jit,
/*
* Compile eBPF program "fp"
*/
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *fp)
{
struct bpf_binary_header *header;
struct s390_jit_data *jit_data;
diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c
index e83e29137566..2fa0e9375127 100644
--- a/arch/sparc/net/bpf_jit_comp_64.c
+++ b/arch/sparc/net/bpf_jit_comp_64.c
@@ -1477,7 +1477,7 @@ struct sparc64_jit_data {
struct jit_ctx ctx;
};
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct sparc64_jit_data *jit_data;
struct bpf_binary_header *header;
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 77d00a8dec87..72d9a5faa230 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -3713,7 +3713,7 @@ struct x64_jit_data {
#define MAX_PASSES 20
#define PADDING_PASSES (MAX_PASSES - 5)
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_binary_header *rw_header = NULL;
struct bpf_binary_header *header = NULL;
diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
index 5f259577614a..852baf2e4db4 100644
--- a/arch/x86/net/bpf_jit_comp32.c
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -2518,7 +2518,7 @@ bool bpf_jit_needs_zext(void)
return true;
}
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_binary_header *header = NULL;
int proglen, oldproglen = 0;
diff --git a/include/linux/filter.h b/include/linux/filter.h
index d8c97f463e0f..fe19faae35bb 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1108,6 +1108,8 @@ static inline int sk_filter_reason(struct sock *sk, struct sk_buff *skb,
return sk_filter_trim_cap(sk, skb, 1, reason);
}
+struct bpf_prog *__bpf_prog_select_runtime(struct bpf_verifier_env *env, struct bpf_prog *fp,
+ int *err);
struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
void bpf_prog_free(struct bpf_prog *fp);
@@ -1153,7 +1155,7 @@ u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
(void *)__bpf_call_base)
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog);
void bpf_jit_compile(struct bpf_prog *prog);
bool bpf_jit_needs_zext(void);
bool bpf_jit_inlines_helper_call(s32 imm);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 8f52f4b6c3af..fa3d6d8d76da 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1490,23 +1490,6 @@ void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other)
bpf_prog_clone_free(fp_other);
}
-static void adjust_insn_arrays(struct bpf_prog *prog, u32 off, u32 len)
-{
-#ifdef CONFIG_BPF_SYSCALL
- struct bpf_map *map;
- int i;
-
- if (len <= 1)
- return;
-
- for (i = 0; i < prog->aux->used_map_cnt; i++) {
- map = prog->aux->used_maps[i];
- if (map->map_type == BPF_MAP_TYPE_INSN_ARRAY)
- bpf_insn_array_adjust(map, off, len);
- }
-#endif
-}
-
struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
struct bpf_insn insn_buff[16], aux[2];
@@ -1579,12 +1562,6 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bp
if (env)
env->prog = clone;
- else
- /* Instructions arrays must be updated using absolute xlated offsets.
- * The arrays have already been adjusted by bpf_patch_insn_data() when
- * env is not NULL.
- */
- adjust_insn_arrays(clone, subprog_start + i, rewritten);
/* Walk new program and skip insns we just inserted. */
insn = clone->insnsi + i + insn_delta;
@@ -2553,13 +2530,13 @@ static bool bpf_prog_select_interpreter(struct bpf_prog *fp)
return select_interpreter;
}
-static struct bpf_prog *bpf_prog_jit_compile(struct bpf_prog *prog)
+static struct bpf_prog *bpf_prog_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
#ifdef CONFIG_BPF_JIT
bool blinded = false;
struct bpf_prog *orig_prog = prog;
- prog = bpf_jit_blind_constants(NULL, orig_prog);
+ prog = bpf_jit_blind_constants(env, orig_prog);
/* If blinding was requested and we failed during blinding, we must fall
* back to the interpreter.
*/
@@ -2569,7 +2546,7 @@ static struct bpf_prog *bpf_prog_jit_compile(struct bpf_prog *prog)
if (prog != orig_prog)
blinded = true;
- prog = bpf_int_jit_compile(prog);
+ prog = bpf_int_jit_compile(env, prog);
if (blinded) {
if (!prog->jited) {
bpf_jit_prog_release_other(orig_prog, prog);
@@ -2582,18 +2559,8 @@ static struct bpf_prog *bpf_prog_jit_compile(struct bpf_prog *prog)
return prog;
}
-/**
- * bpf_prog_select_runtime - select exec runtime for BPF program
- * @fp: bpf_prog populated with BPF program
- * @err: pointer to error variable
- *
- * Try to JIT eBPF program, if JIT is not available, use interpreter.
- * The BPF program will be executed via bpf_prog_run() function.
- *
- * Return: the &fp argument along with &err set to 0 for success or
- * a negative errno code on failure
- */
-struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
+struct bpf_prog *__bpf_prog_select_runtime(struct bpf_verifier_env *env, struct bpf_prog *fp,
+ int *err)
{
/* In case of BPF to BPF calls, verifier did all the prep
* work with regards to JITing, etc.
@@ -2621,7 +2588,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
if (*err)
return fp;
- fp = bpf_prog_jit_compile(fp);
+ fp = bpf_prog_jit_compile(env, fp);
bpf_prog_jit_attempt_done(fp);
if (!fp->jited && jit_needed) {
*err = -ENOTSUPP;
@@ -2647,6 +2614,22 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
return fp;
}
+
+/**
+ * bpf_prog_select_runtime - select exec runtime for BPF program
+ * @fp: bpf_prog populated with BPF program
+ * @err: pointer to error variable
+ *
+ * Try to JIT eBPF program, if JIT is not available, use interpreter.
+ * The BPF program will be executed via bpf_prog_run() function.
+ *
+ * Return: the &fp argument along with &err set to 0 for success or
+ * a negative errno code on failure
+ */
+struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
+{
+ return __bpf_prog_select_runtime(NULL, fp, err);
+}
EXPORT_SYMBOL_GPL(bpf_prog_select_runtime);
static unsigned int __bpf_prog_ret1(const void *ctx,
@@ -3134,7 +3117,7 @@ const struct bpf_func_proto bpf_tail_call_proto = {
* It is encouraged to implement bpf_int_jit_compile() instead, so that
* eBPF and implicitly also cBPF can get JITed!
*/
-struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog)
+struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
{
return prog;
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 274039e36465..fb07be46c936 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3090,10 +3090,6 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size)
if (err < 0)
goto free_used_maps;
- prog = bpf_prog_select_runtime(prog, &err);
- if (err < 0)
- goto free_used_maps;
-
err = bpf_prog_mark_insn_arrays_ready(prog);
if (err < 0)
goto free_used_maps;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1b2b99f2d859..89fb700d818f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -23024,7 +23024,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->might_sleep = env->subprog_info[i].might_sleep;
if (!i)
func[i]->aux->exception_boundary = env->seen_exception;
- func[i] = bpf_int_jit_compile(func[i]);
+ func[i] = bpf_int_jit_compile(env, func[i]);
if (!func[i]->jited) {
err = -ENOTSUPP;
goto out_free;
@@ -23068,7 +23068,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
}
for (i = 0; i < env->subprog_cnt; i++) {
old_bpf_func = func[i]->bpf_func;
- tmp = bpf_int_jit_compile(func[i]);
+ tmp = bpf_int_jit_compile(env, func[i]);
if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) {
verbose(env, "JIT doesn't support bpf-to-bpf calls\n");
err = -ENOTSUPP;
@@ -26339,6 +26339,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3
convert_pseudo_ld_imm64(env);
}
+ env->prog = __bpf_prog_select_runtime(env, env->prog, &ret);
+ if (ret)
+ goto err_release_maps;
+
adjust_btf_func(env);
err_release_maps:
--
2.47.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH bpf-next v10 3/5] bpf: Add helper to detect indirect jump targets
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 2/5] bpf: Pass bpf_verifier_env to JIT Xu Kuohai
@ 2026-03-24 12:20 ` Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for " Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target Xu Kuohai
4 siblings, 0 replies; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
From: Xu Kuohai <xukuohai@huawei.com>
Introduce helper bpf_insn_is_indirect_target to check whether a BPF
instruction is an indirect jump target.
Since the verifier knows which instructions are indirect jump targets,
add a new flag indirect_target to struct bpf_insn_aux_data to mark
them. The verifier sets this flag when verifying an indirect jump target
instruction, and the helper checks the flag to determine whether an
instruction is an indirect jump target.
Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
---
include/linux/bpf.h | 2 ++
include/linux/bpf_verifier.h | 9 +++++----
kernel/bpf/core.c | 9 +++++++++
kernel/bpf/verifier.c | 18 ++++++++++++++++++
4 files changed, 34 insertions(+), 4 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 05b34a6355b0..90760e250865 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1541,6 +1541,8 @@ bool bpf_has_frame_pointer(unsigned long ip);
int bpf_jit_charge_modmem(u32 size);
void bpf_jit_uncharge_modmem(u32 size);
bool bpf_prog_has_trampoline(const struct bpf_prog *prog);
+bool bpf_insn_is_indirect_target(const struct bpf_verifier_env *env, const struct bpf_prog *prog,
+ int insn_idx);
#else
static inline int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
struct bpf_trampoline *tr,
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 090aa26d1c98..6431b94746cf 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -578,16 +578,17 @@ struct bpf_insn_aux_data {
/* below fields are initialized once */
unsigned int orig_idx; /* original instruction index */
- bool jmp_point;
- bool prune_point;
+ u32 jmp_point:1;
+ u32 prune_point:1;
/* ensure we check state equivalence and save state checkpoint and
* this instruction, regardless of any heuristics
*/
- bool force_checkpoint;
+ u32 force_checkpoint:1;
/* true if instruction is a call to a helper function that
* accepts callback function as a parameter.
*/
- bool calls_callback;
+ u32 calls_callback:1;
+ u32 indirect_target:1; /* if it is an indirect jump target */
/*
* CFG strongly connected component this instruction belongs to,
* zero if it is a singleton SCC.
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index fa3d6d8d76da..6e0c3f327144 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1572,6 +1572,15 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bp
clone->blinded = 1;
return clone;
}
+
+bool bpf_insn_is_indirect_target(const struct bpf_verifier_env *env, const struct bpf_prog *prog,
+ int insn_idx)
+{
+ if (!env)
+ return false;
+ insn_idx += prog->aux->subprog_start;
+ return env->insn_aux_data[insn_idx].indirect_target;
+}
#endif /* CONFIG_BPF_JIT */
/* Base function for offset calculation. Needs to go into .text section,
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 89fb700d818f..3b81747a1b61 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4028,6 +4028,11 @@ static bool is_jmp_point(struct bpf_verifier_env *env, int insn_idx)
return env->insn_aux_data[insn_idx].jmp_point;
}
+static void mark_indirect_target(struct bpf_verifier_env *env, int idx)
+{
+ env->insn_aux_data[idx].indirect_target = true;
+}
+
#define LR_FRAMENO_BITS 3
#define LR_SPI_BITS 6
#define LR_ENTRY_BITS (LR_SPI_BITS + LR_FRAMENO_BITS + 1)
@@ -21117,12 +21122,14 @@ static int check_indirect_jump(struct bpf_verifier_env *env, struct bpf_insn *in
}
for (i = 0; i < n - 1; i++) {
+ mark_indirect_target(env, env->gotox_tmp_buf->items[i]);
other_branch = push_stack(env, env->gotox_tmp_buf->items[i],
env->insn_idx, env->cur_state->speculative);
if (IS_ERR(other_branch))
return PTR_ERR(other_branch);
}
env->insn_idx = env->gotox_tmp_buf->items[n-1];
+ mark_indirect_target(env, env->insn_idx);
return 0;
}
@@ -22048,6 +22055,17 @@ static void adjust_insn_aux_data(struct bpf_verifier_env *env,
data[i].seen = old_seen;
data[i].zext_dst = insn_has_def32(insn + i);
}
+
+ /* The indirect_target flag of the original instruction was moved to the last of the
+ * new instructions by the above memmove and memset, but the indirect jump target is
+ * actually the first instruction, so move it back. This also matches with the behavior
+ * of bpf_insn_array_adjust(), which preserves xlated_off to point to the first new
+ * instruction.
+ */
+ if (data[off + cnt - 1].indirect_target) {
+ data[off].indirect_target = 1;
+ data[off + cnt - 1].indirect_target = 0;
+ }
}
static void adjust_subprog_starts(struct bpf_verifier_env *env, u32 off, u32 len)
--
2.47.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for indirect jump targets
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
` (2 preceding siblings ...)
2026-03-24 12:20 ` [PATCH bpf-next v10 3/5] bpf: Add helper to detect indirect jump targets Xu Kuohai
@ 2026-03-24 12:20 ` Xu Kuohai
2026-03-25 10:13 ` Leon Hwang
2026-03-24 12:20 ` [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target Xu Kuohai
4 siblings, 1 reply; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
From: Xu Kuohai <xukuohai@huawei.com>
On CPUs that support CET/IBT, the indirect jump selftest triggers
a kernel panic because the indirect jump targets lack ENDBR
instructions.
To fix it, emit an ENDBR instruction to each indirect jump target. Since
the ENDBR instruction shifts the position of original jited instructions,
fix the instruction address calculation wherever the addresses are used.
For reference, below is a sample panic log.
Missing ENDBR: bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x97/0xe1
------------[ cut here ]------------
kernel BUG at arch/x86/kernel/cet.c:133!
Oops: invalid opcode: 0000 [#1] SMP NOPTI
...
? 0xffffffffc00fb258
? bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x97/0xe1
bpf_prog_test_run_syscall+0x110/0x2f0
? fdget+0xba/0xe0
__sys_bpf+0xe4b/0x2590
? __kmalloc_node_track_caller_noprof+0x1c7/0x680
? bpf_prog_test_run_syscall+0x215/0x2f0
__x64_sys_bpf+0x21/0x30
do_syscall_64+0x85/0x620
? bpf_prog_test_run_syscall+0x1e2/0x2f0
Fixes: 493d9e0d6083 ("bpf, x86: add support for indirect jumps")
Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
---
arch/x86/net/bpf_jit_comp.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 72d9a5faa230..ea9e707e8abf 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -58,8 +58,8 @@ static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
#define EMIT_ENDBR() EMIT(gen_endbr(), 4)
#define EMIT_ENDBR_POISON() EMIT(gen_endbr_poison(), 4)
#else
-#define EMIT_ENDBR()
-#define EMIT_ENDBR_POISON()
+#define EMIT_ENDBR() do { } while (0)
+#define EMIT_ENDBR_POISON() do { } while (0)
#endif
static bool is_imm8(int value)
@@ -1649,8 +1649,8 @@ static int emit_spectre_bhb_barrier(u8 **pprog, u8 *ip,
return 0;
}
-static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image,
- int oldproglen, struct jit_context *ctx, bool jmp_padding)
+static int do_jit(struct bpf_verifier_env *env, struct bpf_prog *bpf_prog, int *addrs, u8 *image,
+ u8 *rw_image, int oldproglen, struct jit_context *ctx, bool jmp_padding)
{
bool tail_call_reachable = bpf_prog->aux->tail_call_reachable;
struct bpf_insn *insn = bpf_prog->insnsi;
@@ -1663,7 +1663,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image
void __percpu *priv_stack_ptr;
int i, excnt = 0;
int ilen, proglen = 0;
- u8 *prog = temp;
+ u8 *ip, *prog = temp;
u32 stack_depth;
int err;
@@ -1734,6 +1734,11 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image
dst_reg = X86_REG_R9;
}
+ if (bpf_insn_is_indirect_target(env, bpf_prog, i - 1))
+ EMIT_ENDBR();
+
+ ip = image + addrs[i - 1] + (prog - temp);
+
switch (insn->code) {
/* ALU */
case BPF_ALU | BPF_ADD | BPF_X:
@@ -2440,8 +2445,6 @@ st: if (is_imm8(insn->off))
/* call */
case BPF_JMP | BPF_CALL: {
- u8 *ip = image + addrs[i - 1];
-
func = (u8 *) __bpf_call_base + imm32;
if (src_reg == BPF_PSEUDO_CALL && tail_call_reachable) {
LOAD_TAIL_CALL_CNT_PTR(stack_depth);
@@ -2465,7 +2468,8 @@ st: if (is_imm8(insn->off))
if (imm32)
emit_bpf_tail_call_direct(bpf_prog,
&bpf_prog->aux->poke_tab[imm32 - 1],
- &prog, image + addrs[i - 1],
+ &prog,
+ ip,
callee_regs_used,
stack_depth,
ctx);
@@ -2474,7 +2478,7 @@ st: if (is_imm8(insn->off))
&prog,
callee_regs_used,
stack_depth,
- image + addrs[i - 1],
+ ip,
ctx);
break;
@@ -2639,7 +2643,7 @@ st: if (is_imm8(insn->off))
break;
case BPF_JMP | BPF_JA | BPF_X:
- emit_indirect_jump(&prog, insn->dst_reg, image + addrs[i - 1]);
+ emit_indirect_jump(&prog, insn->dst_reg, ip);
break;
case BPF_JMP | BPF_JA:
case BPF_JMP32 | BPF_JA:
@@ -2729,8 +2733,6 @@ st: if (is_imm8(insn->off))
ctx->cleanup_addr = proglen;
if (bpf_prog_was_classic(bpf_prog) &&
!ns_capable_noaudit(&init_user_ns, CAP_SYS_ADMIN)) {
- u8 *ip = image + addrs[i - 1];
-
if (emit_spectre_bhb_barrier(&prog, ip, bpf_prog))
return -EINVAL;
}
@@ -3791,7 +3793,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_pr
for (pass = 0; pass < MAX_PASSES || image; pass++) {
if (!padding && pass >= PADDING_PASSES)
padding = true;
- proglen = do_jit(prog, addrs, image, rw_image, oldproglen, &ctx, padding);
+ proglen = do_jit(env, prog, addrs, image, rw_image, oldproglen, &ctx, padding);
if (proglen <= 0) {
out_image:
image = NULL;
--
2.47.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
` (3 preceding siblings ...)
2026-03-24 12:20 ` [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for " Xu Kuohai
@ 2026-03-24 12:20 ` Xu Kuohai
2026-03-25 10:14 ` Leon Hwang
4 siblings, 1 reply; 11+ messages in thread
From: Xu Kuohai @ 2026-03-24 12:20 UTC (permalink / raw)
To: bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
From: Xu Kuohai <xukuohai@huawei.com>
On CPUs that support BTI, the indirect jump selftest triggers a kernel
panic because there is no BTI instructions at the indirect jump targets.
Fix it by emitting a BTI instruction for each indirect jump target.
For reference, below is a sample panic log.
Internal error: Oops - BTI: 0000000036000003 [#1] SMP
...
Call trace:
bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x54/0xf8 (P)
bpf_prog_run_pin_on_cpu+0x140/0x468
bpf_prog_test_run_syscall+0x280/0x3b8
bpf_prog_test_run+0x22c/0x2c0
Fixes: f4a66cf1cb14 ("bpf: arm64: Add support for indirect jumps")
Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
---
arch/arm64/net/bpf_jit_comp.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index 7212ec89dfe3..aa5cd240cdda 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -1198,8 +1198,8 @@ static int add_exception_handler(const struct bpf_insn *insn,
* >0 - successfully JITed a 16-byte eBPF instruction.
* <0 - failed to JIT.
*/
-static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
- bool extra_pass)
+static int build_insn(const struct bpf_verifier_env *env, const struct bpf_insn *insn,
+ struct jit_ctx *ctx, bool extra_pass)
{
const u8 code = insn->code;
u8 dst = bpf2a64[insn->dst_reg];
@@ -1224,6 +1224,9 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
int ret;
bool sign_extend;
+ if (bpf_insn_is_indirect_target(env, ctx->prog, i))
+ emit_bti(A64_BTI_J, ctx);
+
switch (code) {
/* dst = src */
case BPF_ALU | BPF_MOV | BPF_X:
@@ -1899,7 +1902,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
return 0;
}
-static int build_body(struct jit_ctx *ctx, bool extra_pass)
+static int build_body(struct bpf_verifier_env *env, struct jit_ctx *ctx, bool extra_pass)
{
const struct bpf_prog *prog = ctx->prog;
int i;
@@ -1918,7 +1921,7 @@ static int build_body(struct jit_ctx *ctx, bool extra_pass)
int ret;
ctx->offset[i] = ctx->idx;
- ret = build_insn(insn, ctx, extra_pass);
+ ret = build_insn(env, insn, ctx, extra_pass);
if (ret > 0) {
i++;
ctx->offset[i] = ctx->idx;
@@ -2079,7 +2082,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_pr
if (build_prologue(&ctx, was_classic))
goto out_off;
- if (build_body(&ctx, extra_pass))
+ if (build_body(env, &ctx, extra_pass))
goto out_off;
ctx.epilogue_offset = ctx.idx;
@@ -2127,7 +2130,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_pr
/* Dont write body instructions to memory for now */
ctx.write = false;
- if (build_body(&ctx, extra_pass))
+ if (build_body(env, &ctx, extra_pass))
goto out_free_hdr;
ctx.epilogue_offset = ctx.idx;
@@ -2136,7 +2139,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_pr
ctx.write = true;
/* Pass 3: Adjust jump offset and write final image */
- if (build_body(&ctx, extra_pass) ||
+ if (build_body(env, &ctx, extra_pass) ||
WARN_ON_ONCE(ctx.idx != ctx.epilogue_offset))
goto out_free_hdr;
--
2.47.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs
2026-03-24 12:20 ` [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs Xu Kuohai
@ 2026-03-24 12:46 ` bot+bpf-ci
2026-03-25 7:47 ` Xu Kuohai
0 siblings, 1 reply; 11+ messages in thread
From: bot+bpf-ci @ 2026-03-24 12:46 UTC (permalink / raw)
To: xukuohai, bpf, linux-kernel, linux-arm-kernel
Cc: ast, daniel, andrii, martin.lau, eddyz87, yonghong.song, puranjay,
a.s.protopopov, alexis.lothore, list+bpf, linux, yangtiezhu,
hengqi.chen, johan.almbladh, paulburton, hbathini, chleroy,
naveen, luke.r.nels, xi.wang, bjorn, pulehui, iii, hca, gor,
davem, udknight, ast, andrii, daniel, martin.lau, eddyz87,
yonghong.song, clm, ihor.solodrai
[-- Attachment #1: Type: text/plain, Size: 3978 bytes --]
> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
> index 67eb12b637a5..8f52f4b6c3af 100644
> --- a/kernel/bpf/core.c
> +++ b/kernel/bpf/core.c
[ ... ]
> @@ -1507,13 +1507,16 @@ static void adjust_insn_arrays(struct bpf_prog *prog, u32 off, u32 len)
> #endif
> }
>
> -struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
> +struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
> {
[ ... ]
> - tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
> - if (IS_ERR(tmp)) {
> + if (env)
> + tmp = bpf_patch_insn_data(env, subprog_start + i, insn_buff, rewritten);
> + else
> + tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
When env is non-NULL, bpf_patch_insn_data() adjusts env->insn_aux_data
via adjust_insn_aux_data() and env->subprog_info via
adjust_subprog_starts(). This shifts subprogram start positions to
account for the expanded instructions.
> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> index cd008b146ee5..1b2b99f2d859 100644
> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
[ ... ]
> static int jit_subprogs(struct bpf_verifier_env *env)
> {
> - struct bpf_prog *prog = env->prog, **func, *tmp;
> + struct bpf_prog *orig_prog = env->prog, *prog, **func, *tmp;
> int i, j, subprog_start, subprog_end = 0, len, subprog;
> struct bpf_map *map_ptr;
> struct bpf_insn *insn;
> void *old_bpf_func;
> int err, num_exentries;
> - int old_len, subprog_start_adjustment = 0;
> + bool blinded = false;
>
> if (env->subprog_cnt <= 1)
> return 0;
>
> + prog = bpf_jit_blind_constants(env, NULL);
> + if (IS_ERR(prog))
> + return -ENOMEM;
> + if (prog != orig_prog)
> + blinded = true;
[ ... ]
> + if (blinded) {
> + bpf_jit_prog_release_other(orig_prog, prog);
> + env->prog = prog = orig_prog;
> + }
> /* cleanup main prog to be interpreted */
> prog->jit_requested = 0;
> prog->blinding_requested = 0;
> - for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
> - if (!bpf_pseudo_call(insn))
> - continue;
> - insn->off = 0;
> - insn->imm = env->insn_aux_data[i].call_imm;
> + /* we already rolled back to the clean orig_prog when blinded is true */
> + if (!blinded) {
> + for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
> + if (!bpf_pseudo_call(insn))
> + continue;
> + insn->off = 0;
> + insn->imm = env->insn_aux_data[i].call_imm;
> + }
> }
> bpf_prog_jit_attempt_done(prog);
> return err;
When blinded is true, the rollback restores env->prog to orig_prog, but
env->subprog_info still holds the shifted start positions from blinding
(adjusted by adjust_subprog_starts() in bpf_patch_insn_data()). The
commit message states "env->insn_aux_data and env->subprog_info are no
longer used after JIT failure." However, on configurations without
CONFIG_BPF_JIT_ALWAYS_ON, fixup_call_args() falls through to the
interpreter fixup loop after jit_subprogs() fails:
fixup_call_args() {
err = jit_subprogs(env); /* fails, e.g. -ENOTSUPP */
...
for (i = 0; i < prog->len; ...) {
...
depth = get_callee_stack_depth(env, insn, i);
}
}
get_callee_stack_depth() computes a target address from orig_prog's
original instruction offsets and calls find_subprog(env, start). Since
env->subprog_info start positions were shifted by blinding but the
instruction addresses are from the unblinded orig_prog, find_subprog()
fails to find a matching entry and returns -ENOENT, triggering a
spurious "verifier bug" warning and rejecting the program.
Could env->subprog_info be restored alongside the prog rollback, or
could jit_subprogs() return -EFAULT when blinding was active to skip
the interpreter fallback path?
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/23488858455
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs
2026-03-24 12:46 ` bot+bpf-ci
@ 2026-03-25 7:47 ` Xu Kuohai
2026-03-25 15:12 ` Alexei Starovoitov
0 siblings, 1 reply; 11+ messages in thread
From: Xu Kuohai @ 2026-03-25 7:47 UTC (permalink / raw)
To: bot+bpf-ci, bpf, linux-kernel, linux-arm-kernel
Cc: ast, daniel, andrii, martin.lau, eddyz87, yonghong.song, puranjay,
a.s.protopopov, alexis.lothore, list+bpf, linux, yangtiezhu,
hengqi.chen, johan.almbladh, paulburton, hbathini, chleroy,
naveen, luke.r.nels, xi.wang, bjorn, pulehui, iii, hca, gor,
davem, udknight, martin.lau, clm, ihor.solodrai
On 3/24/2026 8:46 PM, bot+bpf-ci@kernel.org wrote:
>> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
>> index 67eb12b637a5..8f52f4b6c3af 100644
>> --- a/kernel/bpf/core.c
>> +++ b/kernel/bpf/core.c
>
> [ ... ]
>
>> @@ -1507,13 +1507,16 @@ static void adjust_insn_arrays(struct bpf_prog *prog, u32 off, u32 len)
>> #endif
>> }
>>
>> -struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
>> +struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
>> {
>
> [ ... ]
>
>> - tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
>> - if (IS_ERR(tmp)) {
>> + if (env)
>> + tmp = bpf_patch_insn_data(env, subprog_start + i, insn_buff, rewritten);
>> + else
>> + tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
>
> When env is non-NULL, bpf_patch_insn_data() adjusts env->insn_aux_data
> via adjust_insn_aux_data() and env->subprog_info via
> adjust_subprog_starts(). This shifts subprogram start positions to
> account for the expanded instructions.
>
Right, but only the subsequent subprogs are shifted, the current subprog
is not. Since we are patching the main prog when env is non-NULL, and
subprog_start is always 0 for a main prog, subprog_start is not needed
here and can be removed.
>> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
>> index cd008b146ee5..1b2b99f2d859 100644
>> --- a/kernel/bpf/verifier.c
>> +++ b/kernel/bpf/verifier.c
>
[ ... ]
>> }
>> bpf_prog_jit_attempt_done(prog);
>> return err;
>
> When blinded is true, the rollback restores env->prog to orig_prog, but
> env->subprog_info still holds the shifted start positions from blinding
> (adjusted by adjust_subprog_starts() in bpf_patch_insn_data()). The
> commit message states "env->insn_aux_data and env->subprog_info are no
> longer used after JIT failure." However, on configurations without
> CONFIG_BPF_JIT_ALWAYS_ON, fixup_call_args() falls through to the
> interpreter fixup loop after jit_subprogs() fails:
>
> fixup_call_args() {
> err = jit_subprogs(env); /* fails, e.g. -ENOTSUPP */
> ...
> for (i = 0; i < prog->len; ...) {
> ...
> depth = get_callee_stack_depth(env, insn, i);
> }
> }
>
> get_callee_stack_depth() computes a target address from orig_prog's
> original instruction offsets and calls find_subprog(env, start). Since
> env->subprog_info start positions were shifted by blinding but the
> instruction addresses are from the unblinded orig_prog, find_subprog()
> fails to find a matching entry and returns -ENOENT, triggering a
> spurious "verifier bug" warning and rejecting the program.
>
> Could env->subprog_info be restored alongside the prog rollback, or
> could jit_subprogs() return -EFAULT when blinding was active to skip
> the interpreter fallback path?
>
We can save and restore env->subprog_info. Since only the subprog start
values in the subprog_info array are adjusted by the patching function,
I will just back up the original values and restore them on failure,
without duplicating the full subprog_info array.
>
> ---
> AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
> See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
>
> CI run summary: https://github.com/kernel-patches/bpf/actions/runs/23488858455
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for indirect jump targets
2026-03-24 12:20 ` [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for " Xu Kuohai
@ 2026-03-25 10:13 ` Leon Hwang
0 siblings, 0 replies; 11+ messages in thread
From: Leon Hwang @ 2026-03-25 10:13 UTC (permalink / raw)
To: xukuohai
Cc: a.s.protopopov, alexis.lothore, andrii, ast, bjorn, bpf, chleroy,
daniel, davem, eddyz87, gor, hbathini, hca, hengqi.chen, iii,
johan.almbladh, linux-arm-kernel, linux-kernel, linux, list+bpf,
luke.r.nels, martin.lau, naveen, paulburton, pulehui, puranjay,
udknight, xi.wang, yangtiezhu, yonghong.song, Leon Hwang
On Tue, Mar 24, 2026 at 08:20:51PM +0800, Xu Kuohai wrote:
>From: Xu Kuohai <xukuohai@huawei.com>
>
>On CPUs that support CET/IBT, the indirect jump selftest triggers
>a kernel panic because the indirect jump targets lack ENDBR
>instructions.
>
>To fix it, emit an ENDBR instruction to each indirect jump target. Since
>the ENDBR instruction shifts the position of original jited instructions,
>fix the instruction address calculation wherever the addresses are used.
>
>For reference, below is a sample panic log.
>
> Missing ENDBR: bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x97/0xe1
> ------------[ cut here ]------------
> kernel BUG at arch/x86/kernel/cet.c:133!
> Oops: invalid opcode: 0000 [#1] SMP NOPTI
>
> ...
>
> ? 0xffffffffc00fb258
> ? bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x97/0xe1
> bpf_prog_test_run_syscall+0x110/0x2f0
> ? fdget+0xba/0xe0
> __sys_bpf+0xe4b/0x2590
> ? __kmalloc_node_track_caller_noprof+0x1c7/0x680
> ? bpf_prog_test_run_syscall+0x215/0x2f0
> __x64_sys_bpf+0x21/0x30
> do_syscall_64+0x85/0x620
> ? bpf_prog_test_run_syscall+0x1e2/0x2f0
>
>Fixes: 493d9e0d6083 ("bpf, x86: add support for indirect jumps")
>Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
>Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Acked-by: Leon Hwang <leon.hwang@linux.dev>
[...]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target
2026-03-24 12:20 ` [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target Xu Kuohai
@ 2026-03-25 10:14 ` Leon Hwang
0 siblings, 0 replies; 11+ messages in thread
From: Leon Hwang @ 2026-03-25 10:14 UTC (permalink / raw)
To: Xu Kuohai, bpf, linux-kernel, linux-arm-kernel
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard Zingerman, Yonghong Song, Puranjay Mohan,
Anton Protopopov, Alexis Lothoré, Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S . Miller,
Wang YanQing
On 24/3/26 20:20, Xu Kuohai wrote:
> From: Xu Kuohai <xukuohai@huawei.com>
>
> On CPUs that support BTI, the indirect jump selftest triggers a kernel
> panic because there is no BTI instructions at the indirect jump targets.
>
> Fix it by emitting a BTI instruction for each indirect jump target.
>
> For reference, below is a sample panic log.
>
> Internal error: Oops - BTI: 0000000036000003 [#1] SMP
> ...
> Call trace:
> bpf_prog_2e5f1c71c13ac3e0_big_jump_table+0x54/0xf8 (P)
> bpf_prog_run_pin_on_cpu+0x140/0x468
> bpf_prog_test_run_syscall+0x280/0x3b8
> bpf_prog_test_run+0x22c/0x2c0
>
> Fixes: f4a66cf1cb14 ("bpf: arm64: Add support for indirect jumps")
> Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com>
> Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Acked-by: Leon Hwang <leon.hwang@linux.dev>
> ---
[...]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs
2026-03-25 7:47 ` Xu Kuohai
@ 2026-03-25 15:12 ` Alexei Starovoitov
0 siblings, 0 replies; 11+ messages in thread
From: Alexei Starovoitov @ 2026-03-25 15:12 UTC (permalink / raw)
To: Xu Kuohai
Cc: bot+bpf-ci, bpf, LKML, linux-arm-kernel, Alexei Starovoitov,
Daniel Borkmann, Andrii Nakryiko, Martin KaFai Lau, Eduard,
Yonghong Song, Puranjay Mohan, Anton Protopopov,
Alexis Lothoré (eBPF Foundation), Shahab Vahedi,
Russell King, Tiezhu Yang, Hengqi Chen, Johan Almbladh,
Paul Burton, Hari Bathini, Christophe Leroy, Naveen N. Rao,
Luke Nelson, Xi Wang, Björn Töpel, Pu Lehui,
Ilya Leoshkevich, Heiko Carstens, Vasily Gorbik, David S. Miller,
Wang YanQing, Martin KaFai Lau, Chris Mason, Ihor Solodrai
On Wed, Mar 25, 2026 at 12:47 AM Xu Kuohai <xukuohai@huaweicloud.com> wrote:
>
> On 3/24/2026 8:46 PM, bot+bpf-ci@kernel.org wrote:
> >> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
> >> index 67eb12b637a5..8f52f4b6c3af 100644
> >> --- a/kernel/bpf/core.c
> >> +++ b/kernel/bpf/core.c
> >
> > [ ... ]
> >
> >> @@ -1507,13 +1507,16 @@ static void adjust_insn_arrays(struct bpf_prog *prog, u32 off, u32 len)
> >> #endif
> >> }
> >>
> >> -struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
> >> +struct bpf_prog *bpf_jit_blind_constants(struct bpf_verifier_env *env, struct bpf_prog *prog)
> >> {
> >
> > [ ... ]
> >
> >> - tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
> >> - if (IS_ERR(tmp)) {
> >> + if (env)
> >> + tmp = bpf_patch_insn_data(env, subprog_start + i, insn_buff, rewritten);
> >> + else
> >> + tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
> >
> > When env is non-NULL, bpf_patch_insn_data() adjusts env->insn_aux_data
> > via adjust_insn_aux_data() and env->subprog_info via
> > adjust_subprog_starts(). This shifts subprogram start positions to
> > account for the expanded instructions.
> >
>
> Right, but only the subsequent subprogs are shifted, the current subprog
> is not. Since we are patching the main prog when env is non-NULL, and
> subprog_start is always 0 for a main prog, subprog_start is not needed
> here and can be removed.
sashiko found other bugs too:
https://sashiko.dev/#/patchset/20260324122052.342751-1-xukuohai%40huaweicloud.com
Pls fix them all.
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2026-03-25 15:12 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-03-24 12:20 [PATCH bpf-next v10 0/5] emit ENDBR/BTI instructions for indirect jump targets Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 1/5] bpf: Move constants blinding out of arch-specific JITs Xu Kuohai
2026-03-24 12:46 ` bot+bpf-ci
2026-03-25 7:47 ` Xu Kuohai
2026-03-25 15:12 ` Alexei Starovoitov
2026-03-24 12:20 ` [PATCH bpf-next v10 2/5] bpf: Pass bpf_verifier_env to JIT Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 3/5] bpf: Add helper to detect indirect jump targets Xu Kuohai
2026-03-24 12:20 ` [PATCH bpf-next v10 4/5] bpf, x86: Emit ENDBR for " Xu Kuohai
2026-03-25 10:13 ` Leon Hwang
2026-03-24 12:20 ` [PATCH bpf-next v10 5/5] bpf, arm64: Emit BTI for indirect jump target Xu Kuohai
2026-03-25 10:14 ` Leon Hwang
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