diff options
| author | Cong Wang <xiyou.wangcong@gmail.com> | 2019-01-05 23:45:26 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-22 21:09:50 +0100 |
| commit | 4fa151046fdb214e933e49d20ddd8ec3db914871 (patch) | |
| tree | afed5f507302d442268ca836a4f22f5d03606f9e /net | |
| parent | 7b585b0b02b61c93848b70eaf1d084804e0d404c (diff) | |
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 82cb0e5634bc..5d2214183601 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -146,6 +146,9 @@ 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 */ @@ -170,7 +173,6 @@ 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; |