From: Max Reitz <mre...@redhat.com>
The bs->exact_filename field may not be sufficient to store the full
blkdebug node filename. In this case, we should not generate a filename
at all instead of an unusable one.
Cc: qemu-sta...@nongnu.org
Reported-by: Qu Wenruo <quwen...@cn.fujitsu.com>
Signed-off-by: Max Reitz <mre...@redhat.com>
Message-id: 20170613172006.19685-2-mre...@redhat.com
Reviewed-by: Alberto Garcia <be...@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
Signed-off-by: Max Reitz <mre...@redhat.com>
---
block/blkdebug.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/block/blkdebug.c b/block/blkdebug.c
index 6431962..a1b24b9 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -839,9 +839,13 @@ static void blkdebug_refresh_filename(BlockDriverState
*bs, QDict *options)
}
if (!force_json && bs->file->bs->exact_filename[0]) {
- snprintf(bs->exact_filename, sizeof(bs->exact_filename),
- "blkdebug:%s:%s", s->config_file ?: "",
- bs->file->bs->exact_filename);
+ int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
+ "blkdebug:%s:%s", s->config_file ?: "",
+ bs->file->bs->exact_filename);
+ if (ret >= sizeof(bs->exact_filename)) {
+ /* An overflow makes the filename unusable, so do not report any */
+ bs->exact_filename[0] = 0;
+ }
}
opts = qdict_new();
--
1.8.3.1
