[PATCH 1/3] ASoC: Intel: avs: Fix potential buffer overflow by snprintf()

Takashi Iwai tiwai at suse.de
Mon Aug 1 18:54:18 CEST 2022


snprintf() returns the would-be-filled size when the string overflows
the given buffer size, hence using this value may result in a buffer
overflow (although it's unrealistic).

This patch replaces it with a safer version, scnprintf() for papering
over such a potential issue.

Fixes: f1b3b320bd65 ("ASoC: Intel: avs: Generic soc component driver")
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/soc/intel/avs/pcm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/intel/avs/pcm.c b/sound/soc/intel/avs/pcm.c
index f21b0cdd3206..8fe5917b1e26 100644
--- a/sound/soc/intel/avs/pcm.c
+++ b/sound/soc/intel/avs/pcm.c
@@ -636,8 +636,8 @@ static ssize_t topology_name_read(struct file *file, char __user *user_buf, size
 	char buf[64];
 	size_t len;
 
-	len = snprintf(buf, sizeof(buf), "%s/%s\n", component->driver->topology_name_prefix,
-		       mach->tplg_filename);
+	len = scnprintf(buf, sizeof(buf), "%s/%s\n", component->driver->topology_name_prefix,
+			mach->tplg_filename);
 
 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
 }
-- 
2.35.3



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