Re: Problems with /proc/net/tcp6 - possible bug - ipv6

From: Eric Dumazet <redacted>
Date: Sat, 22 Jan 2011 16:15:44 +0100

[PATCH] tcp: fix bug in listening_get_next()

commit a8b690f98baf9fb19 (tcp: Fix slowness in read /proc/net/tcp)
introduced a bug in handling of SYN_RECV sockets.

st->offset represents number of sockets found since beginning of
listening_hash[st->bucket].

We should not reset st->offset when iterating through
syn_table[st->sbucket], or else if more than ~25 sockets (if
PAGE_SIZE=4096) are in SYN_RECV state, we exit from listening_get_next()
with a too small st->offset

Next time we enter tcp_seek_last_pos(), we are not able to seek past
already found sockets.

Reported-by: PK <redacted>
CC: Tom Herbert <redacted>
Signed-off-by: Eric Dumazet <redacted>

Applied and queued up for -stable, thanks Eric.