[PATCH] scsi: aha1740: Avoid over-read of sense buffer

[PATCH] scsi: aha1740: Avoid over-read of sense buffer

[Kees Cook]

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading across neighboring array fields.

SCtmp->sense_buffer is 96 bytes, but ecbptr->sense is 14 bytes. Instead
of over-reading ecbptr->sense, copy only the actual contents and zero
pad the remaining bytes, avoiding potential over-reads.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/scsi/aha1740.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/aha1740.c b/drivers/scsi/aha1740.c
index 0dc831026e9e..39d8759fe558 100644
--- a/drivers/scsi/aha1740.c
+++ b/drivers/scsi/aha1740.c
@@ -267,8 +267,11 @@ static irqreturn_t aha1740_intr_handle(int irq, void *dev_id)
 			   guarantee that we will still have it in the
 			   cdb when we come back */
 			if ( (adapstat & G2INTST_MASK) == G2INTST_CCBERROR ) {
-				memcpy(SCtmp->sense_buffer, ecbptr->sense, 
-				       SCSI_SENSE_BUFFERSIZE);
+				memcpy_and_pad(SCtmp->sense_buffer,
+					       SCSI_SENSE_BUFFERSIZE,
+					       ecbptr->sense,
+					       sizeof(ecbptr->sense),
+					       0);
 				errstatus = aha1740_makecode(ecbptr->sense,ecbptr->status);
 			} else
 				errstatus = 0;
-- 
2.25.1

Re: [PATCH] scsi: aha1740: Avoid over-read of sense buffer

[Martin K. Petersen]

Kees,

> In preparation for FORTIFY_SOURCE performing compile-time and run-time
> field bounds checking for memcpy(), memmove(), and memset(), avoid
> intentionally reading across neighboring array fields.

Applied to 5.14/scsi-staging, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering