Verify the inode di_forkoff, lifted from xfs_repair's
process_check_inode_forkoff().
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
---
V3: use XFS_DFORK_Q instead of open-coding forkoff check
diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c
index 30d1d60f1d46..09d9c8cfa4a0 100644
--- a/fs/xfs/libxfs/xfs_inode_buf.c
+++ b/fs/xfs/libxfs/xfs_inode_buf.c
@@ -415,6 +415,31 @@ xfs_dinode_verify_fork(
return NULL;
}
+static xfs_failaddr_t
+xfs_dinode_verify_forkoff(
+ struct xfs_dinode *dip,
+ struct xfs_mount *mp)
+{
+ if (!XFS_DFORK_Q(dip))
+ return NULL;
+
+ switch (dip->di_format) {
+ case XFS_DINODE_FMT_DEV:
+ if (dip->di_forkoff != (roundup(sizeof(xfs_dev_t), 8) >> 3))
+ return __this_address;
+ break;
+ case XFS_DINODE_FMT_LOCAL: /* fall through ... */
+ case XFS_DINODE_FMT_EXTENTS: /* fall through ... */
+ case XFS_DINODE_FMT_BTREE:
+ if (dip->di_forkoff >= (XFS_LITINO(mp, dip->di_version) >> 3))
+ return __this_address;
+ break;
+ default:
+ return __this_address;
+ }
+ return NULL;
+}
+
xfs_failaddr_t
xfs_dinode_verify(
struct xfs_mount *mp,
@@ -470,6 +495,11 @@ xfs_dinode_verify(
if (mode && (flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
return __this_address;
+ /* check for illegal values of forkoff */
+ fa = xfs_dinode_verify_forkoff(dip, mp);
+ if (fa)
+ return fa;
+
/* Do we have appropriate data fork formats for the mode? */
switch (mode & S_IFMT) {
case S_IFIFO:
