diff options
| author | Kees Cook <kees@kernel.org> | 2025-11-03 16:26:16 -0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-11-04 19:10:33 -0800 |
| commit | 2b5e9f9b7e414c5eeb20dd7a7b80816ff55cf57b (patch) | |
| tree | 8e72511780bc69941e51a54cfa126f0e9538347a /net/packet | |
| parent | c1a799eef62b8c3298a4d82753fe0f2a448e5e4f (diff) | |
net: Convert struct sockaddr to fixed-size "sa_data[14]"
Revert struct sockaddr from flexible array to fixed 14-byte "sa_data",
to solve over 36,000 -Wflex-array-member-not-at-end warnings, since
struct sockaddr is embedded within many network structs.
With socket/proto sockaddr-based internal APIs switched to use struct
sockaddr_unsized, there should be no more uses of struct sockaddr that
depend on reading beyond the end of struct sockaddr::sa_data that might
trigger bounds checking.
Comparing an x86_64 "allyesconfig" vmlinux build before and after this
patch showed no new "ud1" instructions from CONFIG_UBSAN_BOUNDS nor any
new "field-spanning" memcpy CONFIG_FORTIFY_SOURCE instrumentations.
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-8-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/packet')
| -rw-r--r-- | net/packet/af_packet.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index fccad2a529cc..494d628d10a5 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3284,7 +3284,7 @@ static int packet_bind_spkt(struct socket *sock, struct sockaddr_unsized *uaddr, { struct sock *sk = sock->sk; struct sockaddr *sa = (struct sockaddr *)uaddr; - char name[sizeof(sa->sa_data_min) + 1]; + char name[sizeof(sa->sa_data) + 1]; /* * Check legality @@ -3295,8 +3295,8 @@ static int packet_bind_spkt(struct socket *sock, struct sockaddr_unsized *uaddr, /* uaddr->sa_data comes from the userspace, it's not guaranteed to be * zero-terminated. */ - memcpy(name, sa->sa_data, sizeof(sa->sa_data_min)); - name[sizeof(sa->sa_data_min)] = 0; + memcpy(name, sa->sa_data, sizeof(sa->sa_data)); + name[sizeof(sa->sa_data)] = 0; return packet_do_bind(sk, name, 0, 0); } @@ -3581,11 +3581,11 @@ static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, return -EOPNOTSUPP; uaddr->sa_family = AF_PACKET; - memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data_min)); + memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), READ_ONCE(pkt_sk(sk)->ifindex)); if (dev) - strscpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data_min)); + strscpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); rcu_read_unlock(); return sizeof(*uaddr); |