[PATCH AUTOSEL 4.9 19/23] net: mac802154: Fix general protection fault

From: Sasha Levin
Date: Mon Apr 12 2021 - 12:48:05 EST


From: Pavel Skripkin <paskripkin@xxxxxxxxx>

[ Upstream commit 1165affd484889d4986cf3b724318935a0b120d8 ]

syzbot found general protection fault in crypto_destroy_tfm()[1].
It was caused by wrong clean up loop in llsec_key_alloc().
If one of the tfm array members is in IS_ERR() range it will
cause general protection fault in clean up function [1].

Call Trace:
crypto_free_aead include/crypto/aead.h:191 [inline] [1]
llsec_key_alloc net/mac802154/llsec.c:156 [inline]
mac802154_llsec_key_add+0x9e0/0xcc0 net/mac802154/llsec.c:249
ieee802154_add_llsec_key+0x56/0x80 net/mac802154/cfg.c:338
rdev_add_llsec_key net/ieee802154/rdev-ops.h:260 [inline]
nl802154_add_llsec_key+0x3d3/0x560 net/ieee802154/nl802154.c:1584
genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
sock_sendmsg_nosec net/socket.c:654 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:674
____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
___sys_sendmsg+0xf3/0x170 net/socket.c:2404
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Reported-by: syzbot+9ec037722d2603a9f52e@xxxxxxxxxxxxxxxxxxxxxxxxx
Acked-by: Alexander Aring <aahringo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210304152125.1052825-1-paskripkin@xxxxxxxxx
Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/mac802154/llsec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac802154/llsec.c b/net/mac802154/llsec.c
index 6a3e1c2181d3..9e885d94e515 100644
--- a/net/mac802154/llsec.c
+++ b/net/mac802154/llsec.c
@@ -158,7 +158,7 @@ llsec_key_alloc(const struct ieee802154_llsec_key *template)
crypto_free_skcipher(key->tfm0);
err_tfm:
for (i = 0; i < ARRAY_SIZE(key->tfm); i++)
- if (key->tfm[i])
+ if (!IS_ERR_OR_NULL(key->tfm[i]))
crypto_free_aead(key->tfm[i]);

kzfree(key);
--
2.30.2