On 3/22/20 7:03 AM, Coly Li wrote:
From: Takashi Iwai <tiwai@xxxxxxx>
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Coly Li <colyli@xxxxxxx>
---
drivers/md/bcache/sysfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 3470fae4eabc..323276994aab 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -154,7 +154,7 @@ static ssize_t bch_snprint_string_list(char *buf,
size_t i;
for (i = 0; list[i]; i++)
- out += snprintf(out, buf + size - out,
+ out += scnprintf(out, buf + size - out,
i == selected ? "[%s] " : "%s ", list[i]);
out[-1] = '\n';
Well, if you already consider a possible overflow here, why don't you
abort the loop once 'out == buf + size' ?
Cheers,
Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
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