diff options
author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2022-09-29 00:25:37 +0900 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-10-03 07:56:02 +0100 |
commit | a91b750fd6629354460282bbf5146c01b05c4859 (patch) | |
tree | 4f7407a3955bcc7abdfa71a8a7def8c3c51334ca | |
parent | ae3ed15da5889263de372ff9df2e83e16acca4cb (diff) |
net: rds: don't hold sock lock when cancelling work from rds_tcp_reset_callbacks()
syzbot is reporting lockdep warning at rds_tcp_reset_callbacks() [1], for
commit ac3615e7f3cffe2a ("RDS: TCP: Reduce code duplication in
rds_tcp_reset_callbacks()") added cancel_delayed_work_sync() into a section
protected by lock_sock() without realizing that rds_send_xmit() might call
lock_sock().
We don't need to protect cancel_delayed_work_sync() using lock_sock(), for
even if rds_{send,recv}_worker() re-queued this work while __flush_work()
from cancel_delayed_work_sync() was waiting for this work to complete,
retried rds_{send,recv}_worker() is no-op due to the absence of RDS_CONN_UP
bit.
Link: https://syzkaller.appspot.com/bug?extid=78c55c7bc6f66e53dce2 [1]
Reported-by: syzbot <syzbot+78c55c7bc6f66e53dce2@syzkaller.appspotmail.com>
Co-developed-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+78c55c7bc6f66e53dce2@syzkaller.appspotmail.com>
Fixes: ac3615e7f3cffe2a ("RDS: TCP: Reduce code duplication in rds_tcp_reset_callbacks()")
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/rds/tcp.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/rds/tcp.c b/net/rds/tcp.c index 73ee2771093d..d0ff413f697c 100644 --- a/net/rds/tcp.c +++ b/net/rds/tcp.c @@ -166,10 +166,10 @@ void rds_tcp_reset_callbacks(struct socket *sock, */ atomic_set(&cp->cp_state, RDS_CONN_RESETTING); wait_event(cp->cp_waitq, !test_bit(RDS_IN_XMIT, &cp->cp_flags)); - lock_sock(osock->sk); /* reset receive side state for rds_tcp_data_recv() for osock */ cancel_delayed_work_sync(&cp->cp_send_w); cancel_delayed_work_sync(&cp->cp_recv_w); + lock_sock(osock->sk); if (tc->t_tinc) { rds_inc_put(&tc->t_tinc->ti_inc); tc->t_tinc = NULL; |