2021-06-17 02:25:20

by Kees Cook

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

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 <[email protected]>
---
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

2021-06-19 09:22:26

by Martin K. Petersen

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

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