]> www.infradead.org Git - users/jedix/linux-maple.git/commit
xfs: fix remote symlinks on V5/CRC filesystems
authorEric Sandeen <sandeen@redhat.com>
Sun, 21 Jun 2015 23:42:48 +0000 (09:42 +1000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 3 Aug 2015 16:29:11 +0000 (09:29 -0700)
commit1d94f9fc91f94dacfce82638a485dcf9474dc305
tree27d2eeabb6f1b29b48b909bd5ebf029c14b158b9
parentf8a895a6704bba5752c136f7338814c40c891e89
xfs: fix remote symlinks on V5/CRC filesystems

commit 2ac56d3d4bd625450a54d4c3f9292d58f6b88232 upstream.

If we create a CRC filesystem, mount it, and create a symlink with
a path long enough that it can't live in the inode, we get a very
strange result upon remount:

# ls -l mnt
total 4
lrwxrwxrwx. 1 root root 929 Jun 15 16:58 link -> XSLM

XSLM is the V5 symlink block header magic (which happens to be
followed by a NUL, so the string looks terminated).

xfs_readlink_bmap() advanced cur_chunk by the size of the header
for CRC filesystems, but never actually used that pointer; it
kept reading from bp->b_addr, which is the start of the block,
rather than the start of the symlink data after the header.

Looks like this problem goes back to v3.10.

Fixing this gets us reading the proper link target, again.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/xfs/xfs_symlink.c