diff options
| author | Andrey Ryabinin <aryabinin@virtuozzo.com> | 2016-05-18 19:19:27 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-05-20 18:05:32 -0400 |
| commit | fc64869c48494a401b1fb627c9ecc4e6c1d74b0d (patch) | |
| tree | 8db60382773d8a27d29cf2270a9778641c8b6354 | |
| parent | 911f6b1f57c48c9f379e6658e2e5198d84acdab3 (diff) | |
| download | linux-fc64869c48494a401b1fb627c9ecc4e6c1d74b0d.tar.bz2 | |
net: sock: move ->sk_shutdown out of bitfields.
->sk_shutdown bits share one bitfield with some other bits in sock struct,
such as ->sk_no_check_[r,t]x, ->sk_userlocks ...
sock_setsockopt() may write to these bits, while holding the socket lock.
In case of AF_UNIX sockets, we change ->sk_shutdown bits while holding only
unix_state_lock(). So concurrent setsockopt() and shutdown() may lead
to corrupting these bits.
Fix this by moving ->sk_shutdown bits out of bitfield into a separate byte.
This will not change the 'struct sock' size since ->sk_shutdown moved into
previously unused 16-bit hole.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sock.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index c9c8b19df27c..649d2a8c17fc 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -382,8 +382,13 @@ struct sock { atomic_t sk_omem_alloc; int sk_sndbuf; struct sk_buff_head sk_write_queue; + + /* + * Because of non atomicity rules, all + * changes are protected by socket lock. + */ kmemcheck_bitfield_begin(flags); - unsigned int sk_shutdown : 2, + unsigned int sk_padding : 2, sk_no_check_tx : 1, sk_no_check_rx : 1, sk_userlocks : 4, @@ -391,6 +396,7 @@ struct sock { sk_type : 16; #define SK_PROTOCOL_MAX U8_MAX kmemcheck_bitfield_end(flags); + int sk_wmem_queued; gfp_t sk_allocation; u32 sk_pacing_rate; /* bytes per second */ @@ -418,6 +424,7 @@ struct sock { struct timer_list sk_timer; ktime_t sk_stamp; u16 sk_tsflags; + u8 sk_shutdown; u32 sk_tskey; struct socket *sk_socket; void *sk_user_data; |