From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Complain if someone calls xfs_buf_item_init on a buffer that is larger
than the dirty bitmap can handle, or tries to log a region that's past
the end of the dirty bitmap.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_buf_item.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 9737f177a49b..be691d1d9fad 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -763,6 +763,15 @@ xfs_buf_item_init(
XFS_BLF_CHUNK);
map_size = DIV_ROUND_UP(chunks, NBWORD);
+ if (map_size > XFS_BLF_DATAMAP_SIZE) {
+ kmem_cache_free(xfs_buf_item_zone, bip);
+ xfs_err(mp,
+ "buffer item dirty bitmap (%u uints) too small to reflect %u bytes!",
+ map_size,
+ BBTOB(bp->b_maps[i].bm_len));
+ return -EFSCORRUPTED;
+ }
+
bip->bli_formats[i].blf_type = XFS_LI_BUF;
bip->bli_formats[i].blf_blkno = bp->b_maps[i].bm_bn;
bip->bli_formats[i].blf_len = bp->b_maps[i].bm_len;
@@ -795,6 +804,9 @@ xfs_buf_item_log_segment(
uint end_bit;
uint mask;
+ ASSERT(first < XFS_BLF_DATAMAP_SIZE * XFS_BLF_CHUNK * NBWORD);
+ ASSERT(last < XFS_BLF_DATAMAP_SIZE * XFS_BLF_CHUNK * NBWORD);
+
/*
* Convert byte offsets to bit numbers.
*/
