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| author | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2022-09-29 13:27:13 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-10-26 13:22:51 +0200 |
| commit | 7d6f9cb24d2b2f6b6370eac074e2e6b1bafdad45 (patch) | |
| tree | 416d7b4bf4538d4fbaf3e407a668ecc4b313b28d | |
| parent | a76462dbdd8bddcbeec9463bc9e54e509b860762 (diff) | |
| download | linux-stable-7d6f9cb24d2b2f6b6370eac074e2e6b1bafdad45.tar.gz linux-stable-7d6f9cb24d2b2f6b6370eac074e2e6b1bafdad45.tar.bz2 linux-stable-7d6f9cb24d2b2f6b6370eac074e2e6b1bafdad45.zip | |
Bluetooth: L2CAP: Fix user-after-free
[ Upstream commit 35fcbc4243aad7e7d020b7c1dfb14bb888b20a4f ]
This uses l2cap_chan_hold_unless_zero() after calling
__l2cap_get_chan_blah() to prevent the following trace:
Bluetooth: l2cap_core.c:static void l2cap_chan_destroy(struct kref
*kref)
Bluetooth: chan 0000000023c4974d
Bluetooth: parent 00000000ae861c08
==================================================================
BUG: KASAN: use-after-free in __mutex_waiter_is_first
kernel/locking/mutex.c:191 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common
kernel/locking/mutex.c:671 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x278/0x400
kernel/locking/mutex.c:729
Read of size 8 at addr ffff888006a49b08 by task kworker/u3:2/389
Link: https://lore.kernel.org/lkml/20220622082716.478486-1-lee.jones@linaro.org
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/bluetooth/l2cap_core.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 442432f89be1..2d28b4e49b7a 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4066,6 +4066,12 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, } } + chan = l2cap_chan_hold_unless_zero(chan); + if (!chan) { + err = -EBADSLT; + goto unlock; + } + err = 0; l2cap_chan_lock(chan); @@ -4095,6 +4101,7 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, } l2cap_chan_unlock(chan); + l2cap_chan_put(chan); unlock: mutex_unlock(&conn->chan_lock); |