From: Andrew Price anprice@redhat.com
[ Upstream commit c95346ac918c5badf51b9a7ac58a26d3bd5bb224 ]
In punch_hole(), when the offset lies in the final block for a given height, there is no hole to punch, but the maximum size check fails to detect that. Consequently, punch_hole() will try to punch a hole beyond the end of the metadata and fail. Fix the maximum size check.
Signed-off-by: Andrew Price anprice@redhat.com Signed-off-by: Andreas Gruenbacher agruenba@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/gfs2/bmap.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 63e925aa12a75..1dc0f0bca3ab3 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -1760,7 +1760,8 @@ static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length) struct buffer_head *dibh, *bh; struct gfs2_holder rd_gh; unsigned int bsize_shift = sdp->sd_sb.sb_bsize_shift; - u64 lblock = (offset + (1 << bsize_shift) - 1) >> bsize_shift; + unsigned int bsize = 1 << bsize_shift; + u64 lblock = (offset + bsize - 1) >> bsize_shift; __u16 start_list[GFS2_MAX_META_HEIGHT]; __u16 __end_list[GFS2_MAX_META_HEIGHT], *end_list = NULL; unsigned int start_aligned, end_aligned; @@ -1771,7 +1772,7 @@ static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length) u64 prev_bnr = 0; __be64 *start, *end;
- if (offset >= maxsize) { + if (offset + bsize - 1 >= maxsize) { /* * The starting point lies beyond the allocated meta-data; * there are no blocks do deallocate.