diff options
| author | Cong Wang <xiyou.wangcong@gmail.com> | 2019-01-06 10:45:26 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-22 23:40:31 +0300 |
| commit | 8dc262df0c6f304657a0d6db071a7287390307af (patch) | |
| tree | da96a52022d8c3171bc943a332b7844e0c62456b /net | |
| parent | f352903d5d785339623a7d77a60239c76b80eb6e (diff) | |
| download | linux-8dc262df0c6f304657a0d6db071a7287390307af.tar.xz | |
smc: move unhash as early as possible in smc_release()
[ Upstream commit 26d92e951fe0a44ee4aec157cabb65a818cc8151 ]
In smc_release() we release smc->clcsock before unhash the smc
sock, but a parallel smc_diag_dump() may be still reading
smc->clcsock, therefore this could cause a use-after-free as
reported by syzbot.
Reported-and-tested-by: syzbot+fbd1e5476e4c94c7b34e@syzkaller.appspotmail.com
Fixes: 51f1de79ad8e ("net/smc: replace sock_put worker by socket refcounting")
Cc: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reported-by: syzbot+0bf2e01269f1274b4b03@syzkaller.appspotmail.com
Reported-by: syzbot+e3132895630f957306bc@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/smc/af_smc.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 2b8f95290627..e6e506b2db99 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -144,6 +144,9 @@ static int smc_release(struct socket *sock) sock_set_flag(sk, SOCK_DEAD); sk->sk_shutdown |= SHUTDOWN_MASK; } + + sk->sk_prot->unhash(sk); + if (smc->clcsock) { if (smc->use_fallback && sk->sk_state == SMC_LISTEN) { /* wake up clcsock accept */ @@ -168,7 +171,6 @@ static int smc_release(struct socket *sock) smc_conn_free(&smc->conn); release_sock(sk); - sk->sk_prot->unhash(sk); sock_put(sk); /* final sock_put */ out: return rc; |