From: Mike Christie michael.christie@oracle.com
mainline inclusion from mainline-v5.15-rc5 commit 258aad75c62146453d03028a44f2f1590d58e1f6 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9R4O4 CVE: CVE-2021-47427
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Commit d39df158518c ("scsi: iscsi: Have abort handler get ref to conn") added iscsi_get_conn()/iscsi_put_conn() calls during abort handling but then also changed the handling of the case where we detect an already completed task where we now end up doing a goto to the common put/cleanup code. This results in a iscsi_task use after free, because the common cleanup code will do a put on the iscsi_task.
This reverts the goto and moves the iscsi_get_conn() to after we've checked if the iscsi_task is valid.
Link: https://lore.kernel.org/r/20211004210608.9962-1-michael.christie@oracle.com Fixes: d39df158518c ("scsi: iscsi: Have abort handler get ref to conn") Signed-off-by: Mike Christie michael.christie@oracle.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Li Nan linan122@huawei.com --- drivers/scsi/libiscsi.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 06246388791f..f1809282b67f 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -2285,11 +2285,6 @@ int iscsi_eh_abort(struct scsi_cmnd *sc) return FAILED; }
- conn = session->leadconn; - iscsi_get_conn(conn->cls_conn); - conn->eh_abort_cnt++; - age = session->age; - spin_lock(&session->back_lock); task = (struct iscsi_task *)sc->SCp.ptr; if (!task || !task->sc) { @@ -2297,8 +2292,16 @@ int iscsi_eh_abort(struct scsi_cmnd *sc) ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
spin_unlock(&session->back_lock); - goto success; + spin_unlock_bh(&session->frwd_lock); + mutex_unlock(&session->eh_mutex); + return SUCCESS; } + + conn = session->leadconn; + iscsi_get_conn(conn->cls_conn); + conn->eh_abort_cnt++; + age = session->age; + ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt); __iscsi_get_task(task); spin_unlock(&session->back_lock);