| Message ID | 20180330073528.20650-2-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/disk-io.c b/disk-io.c index 610963357675..310ab19cf099 100644 --- a/disk-io.c +++ b/disk-io.c @@ -395,10 +395,12 @@ int read_extent_data(struct btrfs_fs_info *fs_info, char *data, u64 logical, } device = multi->stripes[0].dev; - if (device->fd <= 0) - goto err; if (*len > max_len) *len = max_len; + if (device->fd < 0) { + ret = -EIO; + goto err; + } ret = pread64(device->fd, data, *len, multi->stripes[0].physical); if (ret != *len)
When device is missing, read_extent_data() (function exported from old btrfs check code) has the following problems: 1) Modify @len parameter if device is missing If device returned in @multi is missing, @len can be larger than @max_len (originl length). This could confusing caller and underflow the read loop. 2) Still return 0 for missing device It only handles read error, missing device is not handled and 0 is returned. 3) Wrong check for device->fd In fact, 0 is also a valid fd. Although not possible under most case, it's still need fix. Fix them all. Fixes: 1bad2f2f2dfe ("Btrfs-progs: fsck: add an option to check data csums") Signed-off-by: Qu Wenruo <wqu@suse.com> --- disk-io.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)