Messages in this thread Patch in this message | | | From | Tomas Bortoli <> | Subject | [PATCH] /net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree() | Date | Thu, 19 Jul 2018 22:06:07 +0200 |
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The patch adds the flush in p9_mux_poll_stop() as it the function used by p9_conn_destroy(), in turn called by p9_fd_close() to stop the async polling associated with the data regarding the connection.
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+39749ed7d9ef6dfb23f6@syzkaller.appspotmail.com --- As shown by Syzbot, it is possible to provoke a race between p9_fd_close() and p9_poll_workfn() that is called to take care of the async read/write work to do. To make sure p9_fd_close() frees "trans" when it is not used anymore, it has to explicitly call flush_scheduled_work() before the kfree().
net/9p/trans_fd.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index bf459ee0feab..76ae134c05d9 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -185,6 +185,8 @@ static void p9_mux_poll_stop(struct p9_conn *m) spin_lock_irqsave(&p9_poll_lock, flags); list_del_init(&m->poll_pending_link); spin_unlock_irqrestore(&p9_poll_lock, flags); + + flush_scheduled_work(); } /** -- 2.11.0
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