[PATCH 6/8] staging: dream: fix information leak to userland

From: Vasiliy Kulikov
Date: Thu Oct 28 2010 - 16:02:46 EST


Structure msm_audio_stats is copied to userland with some fields unitialized.
It leads to leaking of contents of kernel stack memory.
Also struct msm_audio_config has field "unused" of type array of 3 elements,
not 4. Instead of this, initialize field "type".

Signed-off-by: Vasiliy Kulikov <segooon@xxxxxxxxx>
---
drivers/staging/dream/qdsp5/audio_out.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/staging/dream/qdsp5/audio_out.c b/drivers/staging/dream/qdsp5/audio_out.c
index d20e895..923818d 100644
--- a/drivers/staging/dream/qdsp5/audio_out.c
+++ b/drivers/staging/dream/qdsp5/audio_out.c
@@ -496,6 +496,7 @@ static long audio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

if (cmd == AUDIO_GET_STATS) {
struct msm_audio_stats stats;
+ memset(&stats, 0, sizeof(stats));
stats.byte_count = atomic_read(&audio->out_bytes);
if (copy_to_user((void*) arg, &stats, sizeof(stats)))
return -EFAULT;
@@ -561,10 +562,10 @@ static long audio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
} else {
config.channel_count = 2;
}
+ config.type = 0;
config.unused[0] = 0;
config.unused[1] = 0;
config.unused[2] = 0;
- config.unused[3] = 0;
if (copy_to_user((void*) arg, &config, sizeof(config))) {
rc = -EFAULT;
} else {
--
1.7.0.4

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