[PATCH v2] xfs: fix the symbolic link assert in xfs_ifree

[Mark Tinguely <tinguely@xxxxxxx>]

Adding an extended attribute to a symbolic link can force that
link to an remote extent. xfs_inactive() incorrectly assumes
that any symbolic link small enough to be in the inode core
is incore, resulting in the remote extent to not be removed.
xfs_ifree() will assert on presence of this leaked remote extent.

Signed-off-by: Mark Tinguely <tinguely@xxxxxxx>
---
xfstest is coming.

 fs/xfs/xfs_symlink.c  |   24 +++++++++++++++++++++++-
 fs/xfs/xfs_symlink.h  |    1 +
 fs/xfs/xfs_vnodeops.c |   15 +++------------
 3 files changed, 27 insertions(+), 13 deletions(-)

Index: b/fs/xfs/xfs_symlink.c
===================================================================
--- a/fs/xfs/xfs_symlink.c
+++ b/fs/xfs/xfs_symlink.c
@@ -606,7 +606,7 @@ xfs_inactive_symlink_rmt(
 
        tp = *tpp;
        mp = ip->i_mount;
-       ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip));
+       ASSERT(ip->i_df.if_flags & XFS_IFEXTENTS);
        /*
         * We're freeing a symlink that has some
         * blocks allocated to it.  Free the
@@ -720,3 +720,25 @@ xfs_inactive_symlink_rmt(
  error0:
        return error;
 }
+
+/*
+ * xfs_inactive_symlink - free a symlink
+ */
+int
+xfs_inactive_symlink(
+       struct xfs_inode        *ip,
+       struct xfs_trans        **tp)
+{
+
+       /*
+        * Zero length symlinks _can_ exist.
+        */
+       if (ip->i_df.if_flags & XFS_IFINLINE) {
+               if (ip->i_df.if_bytes > 0)
+                       xfs_idata_realloc(ip, -(ip->i_df.if_bytes),
+                                         XFS_DATA_FORK);
+               ASSERT(ip->i_df.if_bytes == 0);
+               return 0;
+       } else
+               return (xfs_inactive_symlink_rmt(ip, tp));
+}
Index: b/fs/xfs/xfs_symlink.h
===================================================================
--- a/fs/xfs/xfs_symlink.h
+++ b/fs/xfs/xfs_symlink.h
@@ -61,6 +61,7 @@ int xfs_symlink(struct xfs_inode *dp, st
                const char *target_path, umode_t mode, struct xfs_inode **ipp);
 int xfs_readlink(struct xfs_inode *ip, char *link);
 int xfs_inactive_symlink_rmt(struct xfs_inode *ip, struct xfs_trans **tpp);
+int xfs_inactive_symlink(struct xfs_inode *ip, struct xfs_trans **tpp);
 
 #endif /* __KERNEL__ */
 #endif /* __XFS_SYMLINK_H */
Index: b/fs/xfs/xfs_vnodeops.c
===================================================================
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -322,18 +322,9 @@ xfs_inactive(
        xfs_trans_ijoin(tp, ip, 0);
 
        if (S_ISLNK(ip->i_d.di_mode)) {
-               /*
-                * Zero length symlinks _can_ exist.
-                */
-               if (ip->i_d.di_size > XFS_IFORK_DSIZE(ip)) {
-                       error = xfs_inactive_symlink_rmt(ip, &tp);
-                       if (error)
-                               goto out_cancel;
-               } else if (ip->i_df.if_bytes > 0) {
-                       xfs_idata_realloc(ip, -(ip->i_df.if_bytes),
-                                         XFS_DATA_FORK);
-                       ASSERT(ip->i_df.if_bytes == 0);
-               }
+               error = xfs_inactive_symlink(ip, &tp);
+               if (error)
+                       goto out_cancel;
        } else if (truncate) {
                ip->i_d.di_size = 0;
                xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);