[PATCH v2 bpf-next 10/17] bpf: net: Change do_ipv6_getsockopt() to take the sockptr_t argument

Martin KaFai Lau
2022-09-02T00:31:55Z

Similar to the earlier patch that changes sk_getsockopt() to
take the sockptr_t argument . This patch also changes
do_ipv6_getsockopt() to take the sockptr_t argument such that
a latter patch can make bpf_getsockopt(SOL_IPV6) to reuse
do_ipv6_getsockopt().

Note on the change in ip6_mc_msfget(). This function is to
return an array of sockaddr_storage in optval. This function
is shared between ipv6_get_msfilter() and compat_ipv6_get_msfilter().
However, the sockaddr_storage is stored at different offset of the
optval because of the difference between group_filter and
compat_group_filter. Thus, a new 'ss_offset' argument is
added to ip6_mc_msfget().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
---
include/linux/mroute6.h | 4 +--
include/net/ipv6.h | 2 +-
net/ipv6/ip6mr.c | 10 +++---
net/ipv6/ipv6_sockglue.c | 69 ++++++++++++++++++++++------------------
net/ipv6/mcast.c | 8 ++---
5 files changed, 50 insertions(+), 43 deletions(-)

diff --git a/include/linux/mroute6.h b/include/linux/mroute6.h
index bc351a85ce9b..8f2b307fb124 100644
--- a/include/linux/mroute6.h
+++ b/include/linux/mroute6.h
@@ -27,7 +27,7 @@ struct sock;

#ifdef CONFIG_IPV6_MROUTE
extern int ip6_mroute_setsockopt(struct sock *, int, sockptr_t, unsigned int);
-extern int ip6_mroute_getsockopt(struct sock *, int, char __user *, int __user *);
+extern int ip6_mroute_getsockopt(struct sock *, int, sockptr_t, sockptr_t);
extern int ip6_mr_input(struct sk_buff *skb);
extern int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg);
extern int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
@@ -42,7 +42,7 @@ static inline int ip6_mroute_setsockopt(struct sock *sock, int optname,

static inline
int ip6_mroute_getsockopt(struct sock *sock,
- int optname, char __user *optval, int __user *optlen)
+ int optname, sockptr_t optval, sockptr_t optlen)
{
return -ENOPROTOOPT;
}
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index c110d9032083..a4f24573ed7a 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1209,7 +1209,7 @@ int ip6_mc_source(int add, int omode, struct sock *sk,
int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
struct sockaddr_storage *list);
int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
- struct sockaddr_storage __user *p);
+ sockptr_t optval, size_t ss_offset);

#ifdef CONFIG_PROC_FS
int ac6_proc_init(struct net *net);
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index a9ba41648e36..516e83b52f26 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -1827,8 +1827,8 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
* Getsock opt support for the multicast routing system.
*/

-int ip6_mroute_getsockopt(struct sock *sk, int optname, char __user *optval,
- int __user *optlen)
+int ip6_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
+ sockptr_t optlen)
{
int olr;
int val;
@@ -1859,16 +1859,16 @@ int ip6_mroute_getsockopt(struct sock *sk, int optname, char __user *optval,
return -ENOPROTOOPT;
}

- if (get_user(olr, optlen))
+ if (copy_from_sockptr(&olr, optlen, sizeof(int)))
return -EFAULT;

olr = min_t(int, olr, sizeof(int));
if (olr < 0)
return -EINVAL;

- if (put_user(olr, optlen))
+ if (copy_to_sockptr(optlen, &olr, sizeof(int)))
return -EFAULT;
- if (copy_to_user(optval, &val, olr))
+ if (copy_to_sockptr(optval, &val, olr))
return -EFAULT;
return 0;
}
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 4ab284a4adf8..4d9fadef2d3e 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -1030,7 +1030,7 @@ int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
EXPORT_SYMBOL(ipv6_setsockopt);

static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
- int optname, char __user *optval, int len)
+ int optname, sockptr_t optval, int len)
{
struct ipv6_opt_hdr *hdr;

@@ -1058,45 +1058,44 @@ static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
return 0;

len = min_t(unsigned int, len, ipv6_optlen(hdr));
- if (copy_to_user(optval, hdr, len))
+ if (copy_to_sockptr(optval, hdr, len))
return -EFAULT;
return len;
}

-static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
- int __user *optlen, int len)
+static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
+ sockptr_t optlen, int len)
{
const int size0 = offsetof(struct group_filter, gf_slist_flex);
- struct group_filter __user *p = optval;
struct group_filter gsf;
int num;
int err;

if (len < size0)
return -EINVAL;
- if (copy_from_user(&gsf, p, size0))
+ if (copy_from_sockptr(&gsf, optval, size0))
return -EFAULT;
if (gsf.gf_group.ss_family != AF_INET6)
return -EADDRNOTAVAIL;
num = gsf.gf_numsrc;
lock_sock(sk);
- err = ip6_mc_msfget(sk, &gsf, p->gf_slist_flex);
+ err = ip6_mc_msfget(sk, &gsf, optval, size0);
if (!err) {
if (num > gsf.gf_numsrc)
num = gsf.gf_numsrc;
- if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
- copy_to_user(p, &gsf, size0))
+ len = GROUP_FILTER_SIZE(num);
+ if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
+ copy_to_sockptr(optval, &gsf, size0))
err = -EFAULT;
}
release_sock(sk);
return err;
}

-static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
- int __user *optlen, int len)
+static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
+ sockptr_t optlen, int len)
{
const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
- struct compat_group_filter __user *p = optval;
struct compat_group_filter gf32;
struct group_filter gf;
int err;
@@ -1105,7 +1104,7 @@ static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
if (len < size0)
return -EINVAL;

- if (copy_from_user(&gf32, p, size0))
+ if (copy_from_sockptr(&gf32, optval, size0))
return -EFAULT;
gf.gf_interface = gf32.gf_interface;
gf.gf_fmode = gf32.gf_fmode;
@@ -1116,22 +1115,24 @@ static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
return -EADDRNOTAVAIL;

lock_sock(sk);
- err = ip6_mc_msfget(sk, &gf, p->gf_slist_flex);
+ err = ip6_mc_msfget(sk, &gf, optval, size0);
release_sock(sk);
if (err)
return err;
if (num > gf.gf_numsrc)
num = gf.gf_numsrc;
len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
- if (put_user(len, optlen) ||
- put_user(gf.gf_fmode, &p->gf_fmode) ||
- put_user(gf.gf_numsrc, &p->gf_numsrc))
+ if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
+ copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
+ &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
+ copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
+ &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
return -EFAULT;
return 0;
}

static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
- char __user *optval, int __user *optlen)
+ sockptr_t optval, sockptr_t optlen)
{
struct ipv6_pinfo *np = inet6_sk(sk);
int len;
@@ -1140,7 +1141,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
if (ip6_mroute_opt(optname))
return ip6_mroute_getsockopt(sk, optname, optval, optlen);

- if (get_user(len, optlen))
+ if (copy_from_sockptr(&len, optlen, sizeof(int)))
return -EFAULT;
switch (optname) {
case IPV6_ADDRFORM:
@@ -1164,10 +1165,15 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
if (sk->sk_type != SOCK_STREAM)
return -ENOPROTOOPT;

- msg.msg_control_user = optval;
+ if (optval.is_kernel) {
+ msg.msg_control_is_user = false;
+ msg.msg_control = optval.kernel;
+ } else {
+ msg.msg_control_is_user = true;
+ msg.msg_control_user = optval.user;
+ }
msg.msg_controllen = len;
msg.msg_flags = 0;
- msg.msg_control_is_user = true;

lock_sock(sk);
skb = np->pktoptions;
@@ -1210,7 +1216,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
}
}
len -= msg.msg_controllen;
- return put_user(len, optlen);
+ return copy_to_sockptr(optlen, &len, sizeof(int));
}
case IPV6_MTU:
{
@@ -1270,7 +1276,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
/* check if ipv6_getsockopt_sticky() returns err code */
if (len < 0)
return len;
- return put_user(len, optlen);
+ return copy_to_sockptr(optlen, &len, sizeof(int));
}

case IPV6_RECVHOPOPTS:
@@ -1324,9 +1330,9 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
if (!mtuinfo.ip6m_mtu)
return -ENOTCONN;

- if (put_user(len, optlen))
+ if (copy_to_sockptr(optlen, &len, sizeof(int)))
return -EFAULT;
- if (copy_to_user(optval, &mtuinfo, len))
+ if (copy_to_sockptr(optval, &mtuinfo, len))
return -EFAULT;

return 0;
@@ -1403,7 +1409,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
if (len < sizeof(freq))
return -EINVAL;

- if (copy_from_user(&freq, optval, sizeof(freq)))
+ if (copy_from_sockptr(&freq, optval, sizeof(freq)))
return -EFAULT;

if (freq.flr_action != IPV6_FL_A_GET)
@@ -1418,9 +1424,9 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
if (val < 0)
return val;

- if (put_user(len, optlen))
+ if (copy_to_sockptr(optlen, &len, sizeof(int)))
return -EFAULT;
- if (copy_to_user(optval, &freq, len))
+ if (copy_to_sockptr(optval, &freq, len))
return -EFAULT;

return 0;
@@ -1472,9 +1478,9 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
return -ENOPROTOOPT;
}
len = min_t(unsigned int, sizeof(int), len);
- if (put_user(len, optlen))
+ if (copy_to_sockptr(optlen, &len, sizeof(int)))
return -EFAULT;
- if (copy_to_user(optval, &val, len))
+ if (copy_to_sockptr(optval, &val, len))
return -EFAULT;
return 0;
}
@@ -1490,7 +1496,8 @@ int ipv6_getsockopt(struct sock *sk, int level, int optname,
if (level != SOL_IPV6)
return -ENOPROTOOPT;

- err = do_ipv6_getsockopt(sk, level, optname, optval, optlen);
+ err = do_ipv6_getsockopt(sk, level, optname,
+ USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
#ifdef CONFIG_NETFILTER
/* we need to exclude all possible ENOPROTOOPTs except default case */
if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 87c699d57b36..0566ab03ddbe 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -580,7 +580,7 @@ int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
}

int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
- struct sockaddr_storage __user *p)
+ sockptr_t optval, size_t ss_offset)
{
struct ipv6_pinfo *inet6 = inet6_sk(sk);
const struct in6_addr *group;
@@ -612,8 +612,7 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,

copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
gsf->gf_numsrc = count;
-
- for (i = 0; i < copycount; i++, p++) {
+ for (i = 0; i < copycount; i++) {
struct sockaddr_in6 *psin6;
struct sockaddr_storage ss;

@@ -621,8 +620,9 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
memset(&ss, 0, sizeof(ss));
psin6->sin6_family = AF_INET6;
psin6->sin6_addr = psl->sl_addr[i];
- if (copy_to_user(p, &ss, sizeof(ss)))
+ if (copy_to_sockptr_offset(optval, ss_offset, &ss, sizeof(ss)))
return -EFAULT;
+ ss_offset += sizeof(ss);
}
return 0;
}
--
2.30.2