[alsa-devel] [PATCH] ASoC: samsung: i2s: Null pointer dereference on samsung_i2s_remove
If (quirks & QUIRK_SEC_DAI == 0) then samsung_i2s_probe() doesn't allocate sec_dai and pri_dai->sec_dai remains Null, but samsung_i2s_remove() permorms pri_dai->sec_dai dereference in any case.
The patch adds sec_dai check on Null before derefence at samsung_i2s_remove().
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Vasilyev vasilyev@ispras.ru --- sound/soc/samsung/i2s.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/samsung/i2s.c b/sound/soc/samsung/i2s.c index af3ba4d..6beeea8 100644 --- a/sound/soc/samsung/i2s.c +++ b/sound/soc/samsung/i2s.c @@ -1382,7 +1382,8 @@ static int samsung_i2s_remove(struct platform_device *pdev) sec_dai = pri_dai->sec_dai;
pri_dai->sec_dai = NULL; - sec_dai->pri_dai = NULL; + if (sec_dai) + sec_dai->pri_dai = NULL;
pm_runtime_get_sync(&pdev->dev); pm_runtime_disable(&pdev->dev);
On 08/10/2017 05:56 PM, Anton Vasilyev wrote:
If (quirks & QUIRK_SEC_DAI == 0) then samsung_i2s_probe() doesn't allocate sec_dai and pri_dai->sec_dai remains Null, but samsung_i2s_remove() permorms pri_dai->sec_dai dereference in any case.
s/permorms/performs
The patch adds sec_dai check on Null before derefence at samsung_i2s_remove().
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Vasilyev vasilyev@ispras.ru
sound/soc/samsung/i2s.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/samsung/i2s.c b/sound/soc/samsung/i2s.c index af3ba4d..6beeea8 100644 --- a/sound/soc/samsung/i2s.c +++ b/sound/soc/samsung/i2s.c @@ -1382,7 +1382,8 @@ static int samsung_i2s_remove(struct platform_device *pdev) sec_dai = pri_dai->sec_dai;
pri_dai->sec_dai = NULL;
- sec_dai->pri_dai = NULL;
Thanks for the patch. AFAICS above 4 lines could be removed altogether since pri_dai and sec_dai is being allocated with devm_kzalloc(). So initializing in remove() is meaningless as afterwards the data will not be used any more. The memory will be just freed by the devres code.
- if (sec_dai)
sec_dai->pri_dai = NULL;
participants (2)
-
Anton Vasilyev -
Sylwester Nawrocki