lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2()

Submitted by james.smart () james.smart.()@emulex.comSubmitted by Johannes Thumshirn Johannes.Thumshirn@emulex.com

From: Johannes Thumshirn jthumshirn@suse.de

If the bf_get() call in lpfc_mbx_cmpl_rdp_page_a2() does succeeds, execution
continues normally and mp gets kfree()d.

If the subsequent call to lpfc_sli_issue_mbox() fails execution jumps to the
error label where lpfc_mbuf_free() is called with mp-virt and mp-phys as
function arguments. This is the use after free. Following the use after free mp
gets kfree()d again which is a double free.

Signed-off-by: Johannes Thumshirn jthumshirn@suse.de
Signed-off-by: James Smart james.smart@avagotech.com
http://marc.info/?l=linux-scsi&m=144105412703755&w=2

Orabug: 22029622
From dick.kennedy@avagotech.com lpfc-10.5.0.1-11.0.0.3-1.tar.gz
Acked-by: Chuck Anderson <chuck.anderson@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_mbox.c b/drivers/scsi/lpfc/lpfc_mbox.c
index 723e110ce19ba3b811bf5aef46f2a4f3c2bef61f..18838ea4b6aa982c113536e4c55bae360d81c243 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_mbox.c
+++ b/drivers/scsi/lpfc/lpfc_mbox.c
@@ -2276,7 +2276,7 @@ lpfc_mbx_cmpl_rdp_page_a2(struct lpfc_hba *phba, LPFC_MBOXQ_t *mbox)
                        (struct lpfc_rdp_context *)(mbox->context2);
 
        if (bf_get(lpfc_mqe_status, &mbox->u.mqe))
-               goto error;
+               goto error_mbuf_free;
 
        lpfc_sli_bemem_bcopy(mp->virt, &rdp_context->page_a2,
                                DMP_SFF_PAGE_A2_SIZE);
@@ -2291,13 +2291,14 @@ lpfc_mbx_cmpl_rdp_page_a2(struct lpfc_hba *phba, LPFC_MBOXQ_t *mbox)
        mbox->mbox_cmpl = lpfc_mbx_cmpl_rdp_link_stat;
        mbox->context2 = (struct lpfc_rdp_context *) rdp_context;
        if (lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT) == MBX_NOT_FINISHED)
-               goto error;
+               goto error_cmd_free;
 
        return;
 
-error:
+error_mbuf_free:
        lpfc_mbuf_free(phba, mp->virt, mp->phys);
        kfree(mp);
+error_cmd_free:
        lpfc_sli4_mbox_cmd_free(phba, mbox);
        rdp_context->cmpl(phba, rdp_context, FAILURE);
 }