From: Jianglei Nie <niejianglei2021@163.com> stable inclusion from stable-v4.19.238 commit 6044ad64f41c87382cfeeca281573d1886d80cbe category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBPBYM CVE: CVE-2022-49114 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 271add11994ba1a334859069367e04d2be2ebdd4 ] fc_exch_release(ep) will decrease the ep's reference count. When the reference count reaches zero, it is freed. But ep is still used in the following code, which will lead to a use after free. Return after the fc_exch_release() call to avoid use after free. Link: https://lore.kernel.org/r/20220303015115.459778-1-niejianglei2021@163.com Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jianglei Nie <niejianglei2021@163.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Baokun Li <libaokun1@huawei.com> --- drivers/scsi/libfc/fc_exch.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c index 6ba257cbc6d9..e821d4cbe772 100644 --- a/drivers/scsi/libfc/fc_exch.c +++ b/drivers/scsi/libfc/fc_exch.c @@ -1703,6 +1703,7 @@ static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp) if (cancel_delayed_work_sync(&ep->timeout_work)) { FC_EXCH_DBG(ep, "Exchange timer canceled due to ABTS response\n"); fc_exch_release(ep); /* release from pending timer hold */ + return; } spin_lock_bh(&ep->ex_lock); -- 2.46.1