ext4: include terminating u32 in size of xattr entries when expanding inodes
authorTheodore Ts'o <tytso@mit.edu>
Wed, 19 Dec 2018 17:28:13 +0000 (12:28 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 9 Jan 2019 16:45:57 +0000 (17:45 +0100)
commita23f2c8f10e87c98d2dbe4b108a218ee16f5f34b
treec7df7ae825336cf06eac83ff8c1bab2d56500fc0
parent33338ad8cbef78ce5d45734b707fde219c33a429
ext4: include terminating u32 in size of xattr entries when expanding inodes

commit a805622a757b6d7f65def4141d29317d8e37b8a1 upstream.

In ext4_expand_extra_isize_ea(), we calculate the total size of the
xattr header, plus the xattr entries so we know how much of the
beginning part of the xattrs to move when expanding the inode extra
size.  We need to include the terminating u32 at the end of the xattr
entries, or else if there is uninitialized, non-zero bytes after the
xattr entries and before the xattr values, the list of xattr entries
won't be properly terminated.

Reported-by: Steve Graham <stgraham2000@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/ext4/xattr.c