diff options
Diffstat (limited to 'fs/xfs/xfs_symlink.c')
| -rw-r--r-- | fs/xfs/xfs_symlink.c | 33 |
1 files changed, 17 insertions, 16 deletions
diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c index a3e98c64b6e3..b2c1177c717f 100644 --- a/fs/xfs/xfs_symlink.c +++ b/fs/xfs/xfs_symlink.c @@ -192,6 +192,7 @@ xfs_symlink( pathlen = strlen(target_path); if (pathlen >= XFS_SYMLINK_MAXLEN) /* total string too long */ return -ENAMETOOLONG; + ASSERT(pathlen > 0); udqp = gdqp = NULL; prid = xfs_get_initial_prid(dp); @@ -378,6 +379,12 @@ out_release_inode: /* * Free a symlink that has blocks associated with it. + * + * Note: zero length symlinks are not allowed to exist. When we set the size to + * zero, also change it to a regular file so that it does not get written to + * disk as a zero length symlink. The inode is on the unlinked list already, so + * userspace cannot find this inode anymore, so this change is not user visible + * but allows us to catch corrupt zero-length symlinks in the verifiers. */ STATIC int xfs_inactive_symlink_rmt( @@ -412,13 +419,14 @@ xfs_inactive_symlink_rmt( xfs_trans_ijoin(tp, ip, 0); /* - * Lock the inode, fix the size, and join it to the transaction. - * Hold it so in the normal path, we still have it locked for - * the second transaction. In the error paths we need it + * Lock the inode, fix the size, turn it into a regular file and join it + * to the transaction. Hold it so in the normal path, we still have it + * locked for the second transaction. In the error paths we need it * held so the cancel won't rele it, see below. */ size = (int)ip->i_d.di_size; ip->i_d.di_size = 0; + VFS_I(ip)->i_mode = (VFS_I(ip)->i_mode & ~S_IFMT) | S_IFREG; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); /* * Find the block(s) so we can inval and unmap them. @@ -494,17 +502,10 @@ xfs_inactive_symlink( return -EIO; xfs_ilock(ip, XFS_ILOCK_EXCL); - - /* - * Zero length symlinks _can_ exist. - */ pathlen = (int)ip->i_d.di_size; - if (!pathlen) { - xfs_iunlock(ip, XFS_ILOCK_EXCL); - return 0; - } + ASSERT(pathlen); - if (pathlen < 0 || pathlen > XFS_SYMLINK_MAXLEN) { + if (pathlen <= 0 || pathlen > XFS_SYMLINK_MAXLEN) { xfs_alert(mp, "%s: inode (0x%llx) bad symlink length (%d)", __func__, (unsigned long long)ip->i_ino, pathlen); xfs_iunlock(ip, XFS_ILOCK_EXCL); @@ -512,12 +513,12 @@ xfs_inactive_symlink( return -EFSCORRUPTED; } + /* + * Inline fork state gets removed by xfs_difree() so we have nothing to + * do here in that case. + */ 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); xfs_iunlock(ip, XFS_ILOCK_EXCL); - ASSERT(ip->i_df.if_bytes == 0); return 0; } |