path: root/drivers
diff options
authorChris Ball <cjb@laptop.org>2011-04-27 17:35:31 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2011-05-09 15:06:40 -0700
commitd688cdef6b4638f6e4f8127770468a04758487e3 (patch)
tree6558f0fe0a8b067f1e9e4a434cf0602bb58fbaee /drivers
parent40e6af80dbcb551530b6c442564df01f9db3af33 (diff)
mmc: sdhci: Check mrq != NULL in sdhci_tasklet_finish
commit 0c9c99a765321104cc5f9c97f949382a9ba4927e upstream. It seems that under certain circumstances the sdhci_tasklet_finish() call can be entered with mrq set to NULL, causing the system to crash with a NULL pointer de-reference. Seen on S3C6410 system. Based on a patch by Dimitris Papastamos. Reported-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Chris Ball <cjb@laptop.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index fd8f488df5f..5d20661bc35 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1334,6 +1334,13 @@ static void sdhci_tasklet_finish(unsigned long param)
host = (struct sdhci_host*)param;
+ /*
+ * If this tasklet gets rescheduled while running, it will
+ * be run again afterwards but without any active request.
+ */
+ if (!host->mrq)
+ return;
spin_lock_irqsave(&host->lock, flags);