Qu Wenruo
2014-Nov-12 05:52 UTC
[PATCH 1/4] btrfs-progs: Check sb_bytenr with device size before scanning one device.
When using btrfs check with -s option, if using '-s 2' on a small
device which doesn't have the third superblock, "No valid Btrfs
found"
will be output, but it is not appropriate.
So check sb_bytenr against device size before scanning a device and
output proper error message.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
---
disk-io.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/disk-io.c b/disk-io.c
index 77fc610..d2599b5 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -1000,10 +1000,20 @@ int btrfs_scan_fs_devices(int fd, const char *path,
u64 sb_bytenr, int super_recover)
{
u64 total_devs;
+ u64 dev_size;
int ret;
if (!sb_bytenr)
sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
+ dev_size = lseek(fd, 0, SEEK_END);
+ if (dev_size < 0)
+ return (int)(dev_size);
+ lseek(fd, 0, SEEK_SET);
+ if (sb_bytenr > dev_size) {
+ fprintf(stderr, "Superblock bytenr is larger than device size\n");
+ return -EINVAL;
+ }
+
ret = btrfs_scan_one_device(fd, path, fs_devices,
&total_devs, sb_bytenr, super_recover);
if (ret) {
--
2.1.3
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html