[PATCH 5.4 037/320] Bluetooth: cmtp: fix possible panic when cmtp_init_sockets() fails

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 14:37:57 EST


From: Wang Hai <wanghai38@xxxxxxxxxx>

[ Upstream commit 2a7ca7459d905febf519163bd9e3eed894de6bb7 ]

I got a kernel BUG report when doing fault injection test:

------------[ cut here ]------------
kernel BUG at lib/list_debug.c:45!
...
RIP: 0010:__list_del_entry_valid.cold+0x12/0x4d
...
Call Trace:
proto_unregister+0x83/0x220
cmtp_cleanup_sockets+0x37/0x40 [cmtp]
cmtp_exit+0xe/0x1f [cmtp]
do_syscall_64+0x35/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae

If cmtp_init_sockets() in cmtp_init() fails, cmtp_init() still returns
success. This will cause a kernel bug when accessing uncreated ctmp
related data when the module exits.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Wang Hai <wanghai38@xxxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/bluetooth/cmtp/core.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/bluetooth/cmtp/core.c b/net/bluetooth/cmtp/core.c
index 0a2d78e811cf5..83eb84e8e688f 100644
--- a/net/bluetooth/cmtp/core.c
+++ b/net/bluetooth/cmtp/core.c
@@ -501,9 +501,7 @@ static int __init cmtp_init(void)
{
BT_INFO("CMTP (CAPI Emulation) ver %s", VERSION);

- cmtp_init_sockets();
-
- return 0;
+ return cmtp_init_sockets();
}

static void __exit cmtp_exit(void)
--
2.34.1