Fix byte-swapping issues for the i_extra_size field

Thanks to Andreas Dilger and Kalpak Shah for spotting this problem.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/lib/ext2fs/ChangeLog b/lib/ext2fs/ChangeLog
index 02604b5..8ee5d83 100644 (file)
--- a/lib/ext2fs/ChangeLog
+++ b/lib/ext2fs/ChangeLog
@@ -1,3 +1,8 @@
+2007-06-22  Theodore Tso  <tytso@mit.edu>
+
+       * swapfs.c (ext2fs_swap_inode_full): Fix byte-swapping issues for
+               i_extra_size field.
+
 2007-06-12  Theodore Tso  <tytso@mit.edu>
 
        * openfs.c (ext2fs_open2): We now set EXT2_FLAG_MASTER_SB_ONLY

diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c
index a214ad4..a40caa9 100644 (file)
--- a/lib/ext2fs/swapfs.c
+++ b/lib/ext2fs/swapfs.c
@@ -133,7 +133,7 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
                            struct ext2_inode_large *f, int hostorder,
                            int bufsize)
 {
-       unsigned i, has_data_blocks;
+       unsigned i, has_data_blocks, extra_isize;
        int islnk = 0;
        __u32 *eaf, *eat;
 
@@ -214,31 +214,35 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
        if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
                return; /* no i_extra_isize field */
 
+       if (hostorder)
+               extra_isize = f->i_extra_isize;
        t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
-       if (t->i_extra_isize > EXT2_INODE_SIZE(fs->super) -
+       if (!hostorder)
+               extra_isize = t->i_extra_isize;
+       if (extra_isize > EXT2_INODE_SIZE(fs->super) -
                                sizeof(struct ext2_inode)) {
                /* this is error case: i_extra_size is too large */
                return;
        }
 
-       i = sizeof(struct ext2_inode) + t->i_extra_isize + sizeof(__u32);
+       i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
        if (bufsize < (int) i)
                return; /* no space for EA magic */
 
        eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
-                                       f->i_extra_isize);
+                                       extra_isize);
 
        if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
                return; /* it seems no magic here */
 
        eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
-                                       f->i_extra_isize);
+                                       extra_isize);
        *eat = ext2fs_swab32(*eaf);
 
        /* convert EA(s) */
        ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
                             bufsize - sizeof(struct ext2_inode) -
-                            t->i_extra_isize - sizeof(__u32), 0);
+                            extra_isize - sizeof(__u32), 0);
 
 }