diff mbox series

[v16,03/28] xfsprogs: Check for extent overflow when trivally adding a new extent

Message ID 20210326003131.32642-4-allison.henderson@oracle.com (mailing list archive)
State New, archived
Headers show
Series xfsprogs: Delay Ready Attributes | expand

Commit Message

Allison Henderson March 26, 2021, 12:31 a.m. UTC 
From: Chandan Babu R <chandanrlinux@gmail.com>

Source kernel commit: 727e1acd297cae15449607d6e2ee39c71216cf1a

When adding a new data extent (without modifying an inode's existing
extents) the extent count increases only by 1. This commit checks for
extent count overflow in such cases.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
---
 libxfs/xfs_bmap.c       | 6 ++++++
 libxfs/xfs_inode_fork.h | 6 ++++++
 2 files changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index 1e53cbd..336c6d6 100644
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -4520,6 +4520,12 @@  xfs_bmapi_convert_delalloc(
 		return error;
 
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
+
+	error = xfs_iext_count_may_overflow(ip, whichfork,
+			XFS_IEXT_ADD_NOSPLIT_CNT);
+	if (error)
+		goto out_trans_cancel;
+
 	xfs_trans_ijoin(tp, ip, 0);
 
 	if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &bma.icur, &bma.got) ||
diff --git a/libxfs/xfs_inode_fork.h b/libxfs/xfs_inode_fork.h
index 0beb8e2..7fc2b12 100644
--- a/libxfs/xfs_inode_fork.h
+++ b/libxfs/xfs_inode_fork.h
@@ -35,6 +35,12 @@  struct xfs_ifork {
 #define	XFS_IFBROOT	0x04	/* i_broot points to the bmap b-tree root */
 
 /*
+ * Worst-case increase in the fork extent count when we're adding a single
+ * extent to a fork and there's no possibility of splitting an existing mapping.
+ */
+#define XFS_IEXT_ADD_NOSPLIT_CNT	(1)
+
+/*
  * Fork handling.
  */