diff options
| author | Cong Wang <cong.wang@bytedance.com> | 2022-08-27 11:13:14 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-08 12:28:03 +0200 |
| commit | 55fb8c3baa8071c5d533a9ad48624e44e2a04ef5 (patch) | |
| tree | 31f1379729c4bb4e67aaebf4d4b56a917f27125e | |
| parent | 660df4411ef494db2da042024674ebd3cd4c15bf (diff) | |
kcm: fix strp_init() order and cleanup
[ Upstream commit 8fc29ff3910f3af08a7c40a75d436b5720efe2bf ]
strp_init() is called just a few lines above this csk->sk_user_data
check, it also initializes strp->work etc., therefore, it is
unnecessary to call strp_done() to cancel the freshly initialized
work.
And if sk_user_data is already used by KCM, psock->strp should not be
touched, particularly strp->work state, so we need to move strp_init()
after the csk->sk_user_data check.
This also makes a lockdep warning reported by syzbot go away.
Reported-and-tested-by: syzbot+9fc084a4348493ef65d2@syzkaller.appspotmail.com
Reported-by: syzbot+e696806ef96cdd2d87cd@syzkaller.appspotmail.com
Fixes: e5571240236c ("kcm: Check if sk_user_data already set in kcm_attach")
Fixes: dff8baa26117 ("kcm: Call strp_stop before strp_done in kcm_attach")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/20220827181314.193710-1-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/kcm/kcmsock.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index 11a715d76a4f1..f780fbe82e7dc 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1411,12 +1411,6 @@ static int kcm_attach(struct socket *sock, struct socket *csock, psock->sk = csk; psock->bpf_prog = prog; - err = strp_init(&psock->strp, csk, &cb); - if (err) { - kmem_cache_free(kcm_psockp, psock); - goto out; - } - write_lock_bh(&csk->sk_callback_lock); /* Check if sk_user_data is already by KCM or someone else. @@ -1424,13 +1418,18 @@ static int kcm_attach(struct socket *sock, struct socket *csock, */ if (csk->sk_user_data) { write_unlock_bh(&csk->sk_callback_lock); - strp_stop(&psock->strp); - strp_done(&psock->strp); kmem_cache_free(kcm_psockp, psock); err = -EALREADY; goto out; } + err = strp_init(&psock->strp, csk, &cb); + if (err) { + write_unlock_bh(&csk->sk_callback_lock); + kmem_cache_free(kcm_psockp, psock); + goto out; + } + psock->save_data_ready = csk->sk_data_ready; psock->save_write_space = csk->sk_write_space; psock->save_state_change = csk->sk_state_change; |