Hi, On Wed, 3 Mar 2021 at 11:28, Pavel Skripkin <paskripkin@xxxxxxxxx> wrote: > > 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 won't be initialized it will cause > NULL dereference in crypto_destroy_tfm(). > > 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+12cf5fbfdeba210a89dd@xxxxxxxxxxxxxxxxxxxxxxxxx > --- > 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 585d33144c33..6709f186f777 100644 > --- a/net/mac802154/llsec.c > +++ b/net/mac802154/llsec.c > @@ -151,7 +151,7 @@ llsec_key_alloc(const struct ieee802154_llsec_key *template) > err_tfm0: > crypto_free_sync_skcipher(key->tfm0); > err_tfm: > - for (i = 0; i < ARRAY_SIZE(key->tfm); i++) > + for (; i >= 0; i--) > if (key->tfm[i]) I think this need to be: if (!IS_ERR_OR_NULL(key->tfm[i])) otherwise we still run into issues for the current iterator when key->tfm[i] is in range of IS_ERR(). - Alex
