diff mbox

[08/14] lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2()

Message ID 55e4bd8f.66pL9YWWXA/xjdG0%james.smart@avagotech.com (mailing list archive)
State Accepted, archived
Headers show

Commit Message

James Smart Aug. 31, 2015, 8:48 p.m. UTC
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>
---
 drivers/scsi/lpfc/lpfc_mbox.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Comments

Sebastian Herbszt Sept. 1, 2015, 9:37 p.m. UTC | #1
James Smart wrote:
> 
> 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>
> ---
>  drivers/scsi/lpfc/lpfc_mbox.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/scsi/lpfc/lpfc_mbox.c b/drivers/scsi/lpfc/lpfc_mbox.c
> index 723e110..18838ea 100644
> --- 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);
>  }

Reviewed-by: Sebastian Herbszt <herbszt@gmx.de>
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Hannes Reinecke Sept. 14, 2015, 7:37 a.m. UTC | #2
On 08/31/2015 10:48 PM, James Smart wrote:
> 
> 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>
> ---
>  drivers/scsi/lpfc/lpfc_mbox.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/scsi/lpfc/lpfc_mbox.c b/drivers/scsi/lpfc/lpfc_mbox.c
> index 723e110..18838ea 100644
> --- 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);
>  }
> 
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
diff mbox

Patch

diff --git a/drivers/scsi/lpfc/lpfc_mbox.c b/drivers/scsi/lpfc/lpfc_mbox.c
index 723e110..18838ea 100644
--- 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);
 }