This is a note to let you know that I've just added the patch titled
gfs2: Fix invalid metadata access in punch_hole
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gfs2-fix-invalid-metadata-access-in-punch_hole.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 0a4cbfecd444aa3a4220aab2efb19d09fb6501b8
Author: Andrew Price <anprice@xxxxxxxxxx>
Date: Mon Mar 11 16:40:36 2024 +0100
gfs2: Fix invalid metadata access in punch_hole
[ 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@xxxxxxxxxx>
Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index ef7017fb69512..2b578615607e4 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -1715,7 +1715,8 @@ 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;
@@ -1726,7 +1727,7 @@ 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.
