| Message ID | 1381487102-26813-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 43a35db..27a99f7 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -2432,7 +2432,8 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode) int err = 0; /* ext4_handle_valid() assumes a valid handle_t pointer */ - if (handle && !ext4_handle_valid(handle)) + if (handle && !ext4_handle_valid(handle) && + !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) return 0; mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
This is a note to let you know that I have just added a patch titled ext4: avoid hang when mounting non-journal filesystems with to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From dbf829791c9c5dd669b86b332488d916f87570b3 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o <tytso@mit.edu> Date: Thu, 27 Dec 2012 01:42:50 -0500 Subject: [PATCH] ext4: avoid hang when mounting non-journal filesystems with orphan list commit 0e9a9a1ad619e7e987815d20262d36a2f95717ca upstream. When trying to mount a file system which does not contain a journal, but which does have a orphan list containing an inode which needs to be truncated, the mount call with hang forever in ext4_orphan_cleanup() because ext4_orphan_del() will return immediately without removing the inode from the orphan list, leading to an uninterruptible loop in kernel code which will busy out one of the CPU's on the system. This can be trivially reproduced by trying to mount the file system found in tests/f_orphan_extents_inode/image.gz from the e2fsprogs source tree. If a malicious user were to put this on a USB stick, and mount it on a Linux desktop which has automatic mounts enabled, this could be considered a potential denial of service attack. (Not a big deal in practice, but professional paranoids worry about such things, and have even been known to allocate CVE numbers for such problems.) Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Cc: Jan Kara <jack@suse.cz> [ js: This is a fix for CVE-2013-2015. ] Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- fs/ext4/namei.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 1.8.3.2