From c95346ac918c5badf51b9a7ac58a26d3bd5bb224 Mon Sep 17 00:00:00 2001 From: Andrew Price Date: Mon, 11 Mar 2024 16:40:36 +0100 Subject: gfs2: Fix invalid metadata access in punch_hole 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 Signed-off-by: Andreas Gruenbacher --- 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 d9ccfd27e4f11f..643175498d1c3b 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -1718,7 +1718,8 @@ 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; @@ -1729,7 +1730,7 @@ 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 metadata; * there are no blocks to deallocate. -- cgit 1.2.3-korg