| From d0905ca757bc40bd1ebc261a448a521b064777d7 Mon Sep 17 00:00:00 2001 |
| From: Andy Grover <agrover@redhat.com> |
| Date: Mon, 21 Nov 2016 16:35:30 -0800 |
| Subject: target/user: Fix use-after-free of tcmu_cmds if they are expired |
| |
| From: Andy Grover <agrover@redhat.com> |
| |
| commit d0905ca757bc40bd1ebc261a448a521b064777d7 upstream. |
| |
| Don't free the cmd in tcmu_check_expired_cmd, it's still referenced by |
| an entry in our cmd_id->cmd idr. If userspace ever resumes processing, |
| tcmu_handle_completions() will use the now-invalid cmd pointer. |
| |
| Instead, don't free cmd. It will be freed by tcmu_handle_completion() if |
| userspace ever recovers, or tcmu_free_device if not. |
| |
| Reported-by: Bryant G Ly <bgly@us.ibm.com> |
| Tested-by: Bryant G Ly <bgly@us.ibm.com> |
| Signed-off-by: Andy Grover <agrover@redhat.com> |
| Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/target/target_core_user.c | 2 -- |
| 1 file changed, 2 deletions(-) |
| |
| --- a/drivers/target/target_core_user.c |
| +++ b/drivers/target/target_core_user.c |
| @@ -682,8 +682,6 @@ static int tcmu_check_expired_cmd(int id |
| target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); |
| cmd->se_cmd = NULL; |
| |
| - kmem_cache_free(tcmu_cmd_cache, cmd); |
| - |
| return 0; |
| } |
| |
