[PATCH 6.6 078/137] scsi: core: Handle devices which return an unusually large VPD page count

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



6.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Martin K. Petersen <martin.petersen@xxxxxxxxxx>

commit d09c05aa35909adb7d29f92f0cd79fdcd1338ef0 upstream.

Peter Schneider reported that a system would no longer boot after
updating to 6.8.4.  Peter bisected the issue and identified commit
b5fc07a5fb56 ("scsi: core: Consult supported VPD page list prior to
fetching page") as being the culprit.

Turns out the enclosure device in Peter's system reports a byteswapped
page length for VPD page 0. It reports "02 00" as page length instead
of "00 02". This causes us to attempt to access 516 bytes (page length
+ header) of information despite only 2 pages being present.

Limit the page search scope to the size of our VPD buffer to guard
against devices returning a larger page count than requested.

Link: https://lore.kernel.org/r/20240521023040.2703884-1-martin.petersen@xxxxxxxxxx
Fixes: b5fc07a5fb56 ("scsi: core: Consult supported VPD page list prior to fetching page")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Peter Schneider <pschneider1968@xxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/all/eec6ebbf-061b-4a7b-96dc-ea748aa4d035@xxxxxxxxxxxxxx/
Tested-by: Peter Schneider <pschneider1968@xxxxxxxxxxxxxx>
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/scsi/scsi.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -350,6 +350,13 @@ static int scsi_get_vpd_size(struct scsi
 		if (result < SCSI_VPD_HEADER_SIZE)
 			return 0;
 
+		if (result > sizeof(vpd)) {
+			dev_warn_once(&sdev->sdev_gendev,
+				      "%s: long VPD page 0 length: %d bytes\n",
+				      __func__, result);
+			result = sizeof(vpd);
+		}
+
 		result -= SCSI_VPD_HEADER_SIZE;
 		if (!memchr(&vpd[SCSI_VPD_HEADER_SIZE], page, result))
 			return 0;






[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux