mmc: sdhci: Check mrq->cmd in sdhci_tasklet_finish

It seems that under certain circumstances that the sdhci_tasklet_finish()
call can be entered with mrq->cmd set to NULL, causing the system to crash
with a NULL pointer de-reference.

Unable to handle kernel NULL pointer dereference at virtual address 00000000
PC is at sdhci_tasklet_finish+0x34/0xe8
LR is at sdhci_tasklet_finish+0x24/0xe8

Seen on S3C6410 system.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Ben Dooks 2011-04-27 14:24:19 +01:00 committed by Chris Ball
parent c919c2a073
commit b7b4d3426d

View file

@ -1345,7 +1345,7 @@ static void sdhci_tasklet_finish(unsigned long param)
* upon error conditions.
*/
if (!(host->flags & SDHCI_DEVICE_DEAD) &&
(mrq->cmd->error ||
((mrq->cmd && mrq->cmd->error) ||
(mrq->data && (mrq->data->error ||
(mrq->data->stop && mrq->data->stop->error))) ||
(host->quirks & SDHCI_QUIRK_RESET_AFTER_REQUEST))) {