5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeremy Cline <jeremy@xxxxxxxxxx> [ Upstream commit dfc7f7a988dad34c3bf4c053124fb26aa6c5f916 ] The device list needs its associated lock held when modifying it, or the list could become corrupted, as syzbot discovered. Reported-and-tested-by: syzbot+c1d0a03d305972dbbe14@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=c1d0a03d305972dbbe14 Signed-off-by: Jeremy Cline <jeremy@xxxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Fixes: 6709d4b7bc2e ("net: nfc: Fix use-after-free caused by nfc_llcp_find_local") Link: https://lore.kernel.org/r/20230908235853.1319596-1-jeremy@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/nfc/llcp_core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c index ddfd159f64e13..b1107570eaee8 100644 --- a/net/nfc/llcp_core.c +++ b/net/nfc/llcp_core.c @@ -1646,7 +1646,9 @@ int nfc_llcp_register_device(struct nfc_dev *ndev) timer_setup(&local->sdreq_timer, nfc_llcp_sdreq_timer, 0); INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work); + spin_lock(&llcp_devices_lock); list_add(&local->list, &llcp_devices); + spin_unlock(&llcp_devices_lock); return 0; } -- 2.40.1
