kernel/linux.git/include/linux, branch v3.4.112

fs: create and use seq_show_option for escaping

2016-04-27T10:55:18+00:00

commit a068acf2ee77693e0bf39d6e07139ba704f461c3 upstream. Many file systems that implement the show_options hook fail to correctly escape their output which could lead to unescaped characters (e.g. new lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files. This could lead to confusion, spoofed entries (resulting in things like systemd issuing false d-bus "mount" notifications), and who knows what else. This looks like it would only be the root user stepping on themselves, but it's possible weird things could happen in containers or in other situations with delegated mount privileges. Here's an example using overlay with setuid fusermount trusting the contents of /proc/mounts (via the /etc/mtab symlink). Imagine the use of "sudo" is something more sneaky: $ BASE="ovl" $ MNT="$BASE/mnt" $ LOW="$BASE/lower" $ UP="$BASE/upper" $ WORK="$BASE/work/ 0 0 none /proc fuse.pwn user_id=1000" $ mkdir -p "$LOW" "$UP" "$WORK" $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt $ cat /proc/mounts none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0 none /proc fuse.pwn user_id=1000 0 0 $ fusermount -u /proc $ cat /proc/mounts cat: /proc/mounts: No such file or directory This fixes the problem by adding new seq_show_option and seq_show_option_n helpers, and updating the vulnerable show_option handlers to use them as needed. Some, like SELinux, need to be open coded due to unusual existing escape mechanisms. [akpm@linux-foundation.org: add lost chunk, per Kees] [keescook@chromium.org: seq_show_option should be using const parameters] Signed-off-by: Kees Cook Acked-by: Serge Hallyn Acked-by: Jan Kara Acked-by: Paul Moore Cc: J. R. Okajima Signed-off-by: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [lizf: Backported to 3.4: - adjust context - one more place in ceph needs to be changed - drop changes to overlayfs - drop showing vers in cifs] Signed-off-by: Zefan Li

PCI: Add dev_flags bit to access VPD through function 0

2016-04-27T10:55:13+00:00

commit 932c435caba8a2ce473a91753bad0173269ef334 upstream. Add a dev_flags bit, PCI_DEV_FLAGS_VPD_REF_F0, to access VPD through function 0 to provide VPD access on other functions. This is for hardware devices that provide copies of the same VPD capability registers in multiple functions. Because the kernel expects that each function has its own registers, both the locking and the state tracking are affected by VPD accesses to different functions. On such devices for example, if a VPD write is performed on function 0, *any* later attempt to read VPD from any other function of that device will hang. This has to do with how the kernel tracks the expected value of the F bit per function. Concurrent accesses to different functions of the same device can not only hang but also corrupt both read and write VPD data. When hangs occur, typically the error message: vpd r/w failed. This is likely a firmware bug on this device. will be seen. Never set this bit on function 0 or there will be an infinite recursion. Signed-off-by: Mark Rustad Signed-off-by: Bjorn Helgaas Acked-by: Alexander Duyck Signed-off-by: Zefan Li

get rid of s_files and files_lock

2016-03-21T01:17:55+00:00

commit eee5cc2702929fd41cce28058dc6d6717f723f87 upstream. The only thing we need it for is alt-sysrq-r (emergency remount r/o) and these days we can do just as well without going through the list of files. Signed-off-by: Al Viro [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li

libata: add ATA_HORKAGE_NOTRIM

2016-03-21T01:17:45+00:00

commit 71d126fd28de2d4d9b7b2088dbccd7ca62fad6e0 upstream. Some devices lose data on TRIM whether queued or not. This patch adds a horkage to disable TRIM. tj: Collapsed unnecessary if() nesting. Signed-off-by: Arne Fitzenreiter Signed-off-by: Tejun Heo [lizf: Backported to 3.4: - adjust context - drop changes to show_ata_dev_trim()] Signed-off-by: Zefan Li

bufferhead: Add _gfp version for sb_getblk()

2016-03-21T01:17:40+00:00

commit bd7ade3cd9b0850264306f5c2b79024a417b6396 upstream. sb_getblk() is used during ext4 (and possibly other FSes) writeback paths. Sometimes such path require allocating memory and guaranteeing that such allocation won't block. Currently, however, there is no way to provide user flags for sb_getblk which could lead to deadlocks. This patch implements a sb_getblk_gfp with the only difference it can accept user-provided GFP flags. Signed-off-by: Nikolay Borisov Signed-off-by: Theodore Ts'o Signed-off-by: Zefan Li

fs/buffer.c: support buffer cache allocations with gfp modifiers

2016-03-21T01:17:39+00:00

commit 3b5e6454aaf6b4439b19400d8365e2ec2d24e411 upstream. A buffer cache is allocated from movable area because it is referred for a while and released soon. But some filesystems are taking buffer cache for a long time and it can disturb page migration. New APIs are introduced to allocate buffer cache with user specific flag. *_gfp APIs are for user want to set page allocation flag for page cache allocation. And *_unmovable APIs are for the user wants to allocate page cache from non-movable area. Signed-off-by: Gioh Kim Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li

jbd2: avoid infinite loop when destroying aborted journal

2015-10-22T01:20:08+00:00

commit 841df7df196237ea63233f0f9eaa41db53afd70f upstream. Commit 6f6a6fda2945 "jbd2: fix ocfs2 corrupt when updating journal superblock fails" changed jbd2_cleanup_journal_tail() to return EIO when the journal is aborted. That makes logic in jbd2_log_do_checkpoint() bail out which is fine, except that jbd2_journal_destroy() expects jbd2_log_do_checkpoint() to always make a progress in cleaning the journal. Without it jbd2_journal_destroy() just loops in an infinite loop. Fix jbd2_journal_destroy() to cleanup journal checkpoint lists of jbd2_log_do_checkpoint() fails with error. Reported-by: Eryu Guan Tested-by: Eryu Guan Fixes: 6f6a6fda294506dfe0e3e0a253bb2d2923f28f0a Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li

nfs: increase size of EXCHANGE_ID name string buffer

2015-10-22T01:20:05+00:00

commit 764ad8ba8cd4c6f836fca9378f8c5121aece0842 upstream. The current buffer is much too small if you have a relatively long hostname. Bring it up to the size of the one that SETCLIENTID has. Reported-by: Michael Skralivetsky Signed-off-by: Jeff Layton Signed-off-by: Trond Myklebust [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li

jbd2: fix ocfs2 corrupt when updating journal superblock fails

2015-10-22T01:20:04+00:00

commit 6f6a6fda294506dfe0e3e0a253bb2d2923f28f0a upstream. If updating journal superblock fails after journal data has been flushed, the error is omitted and this will mislead the caller as a normal case. In ocfs2, the checkpoint will be treated successfully and the other node can get the lock to update. Since the sb_start is still pointing to the old log block, it will rewrite the journal data during journal recovery by the other node. Thus the new updates will be overwritten and ocfs2 corrupts. So in above case we have to return the error, and ocfs2_commit_cache will take care of the error and prevent the other node to do update first. And only after recovering journal it can do the new updates. The issue discussion mail can be found at: https://oss.oracle.com/pipermail/ocfs2-devel/2015-June/010856.html http://comments.gmane.org/gmane.comp.file-systems.ext4/48841 [ Fixed bug in patch which allowed a non-negative error return from jbd2_cleanup_journal_tail() to leak out of jbd2_fjournal_flush(); this was causing xfstests ext4/306 to fail. -- Ted ] Reported-by: Yiwen Jiang Signed-off-by: Joseph Qi Signed-off-by: Theodore Ts'o Tested-by: Yiwen Jiang Cc: Junxiao Bi Signed-off-by: Zefan Li

libata: Ignore spurious PHY event on LPM policy change

2015-09-18T01:20:37+00:00

commit 09c5b4803a80a5451d950d6a539d2eb311dc0fb1 upstream. When the LPM policy is set to ATA_LPM_MAX_POWER, the device might generate a spurious PHY event that cuases errors on the link. Ignore this event if it occured within 10s after the policy change. The timeout was chosen observing that on a Dell XPS13 9333 these spurious events can occur up to roughly 6s after the policy change. Link: http://lkml.kernel.org/g/3352987.ugV1Ipy7Z5@xps13 Signed-off-by: Gabriele Mazzotta Signed-off-by: Tejun Heo [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li