atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable posix_acl.a_refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
**Important note for maintainers:
Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts.
The full comparison can be seen in
https://lkml.org/lkml/2017/11/15/57 and it is hopefully soon
in state to be merged to the documentation tree.
Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.
For the posix_acl.a_refcount it might make a difference
in following places:
- get_cached_acl(): increment in refcount_inc_not_zero() only
guarantees control dependency on success vs. fully ordered
atomic counterpart. However this operation is performed under
rcu_read_lock(), so this should be fine.
- posix_acl_release(): decrement in refcount_dec_and_test() only
provides RELEASE ordering and control dependency on success
vs. fully ordered atomic counterpart
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: remove repeated f2fs_bug_on which has already existed
in function invalidate_blocks.
Signed-off-by: Zhikang Zhang <zhangzhikang1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Remove the variable page_idx which no one would miss.
Signed-off-by: Fan li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
test/generic/208 reports a potential deadlock as below:
Chain exists of:
&mm->mmap_sem --> &fi->i_mmap_sem --> &fi->dio_rwsem[WRITE]
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&fi->dio_rwsem[WRITE]);
lock(&fi->i_mmap_sem);
lock(&fi->dio_rwsem[WRITE]);
lock(&mm->mmap_sem);
This patch changes the lock dependency as below in fallocate() to
fix this issue:
- dio_rwsem
- i_mmap_sem
Fixes: bb06664a53 ("f2fs: avoid race in between GC and block exchange")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commit d260081ccf ("f2fs: change recovery policy of xattr node block")
removes the use of blkaddr, which is no longer used. So remove the
parameter.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If there is not enough space left, f2fs_preallocate_blocks may only
preallocte partial blocks. As a result, the write operation fails
but i_blocks is not 0. To avoid this, f2fs should write data in
non-preallocation way and write as many data as the size of i_blocks.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a sysfs interface readdir_ra to enable/disable
readaheading inode block in f2fs_readdir. When readdir_ra is enabled,
it improves the performance of "readdir + stat".
For 300,000 files:
time find /data/test > /dev/null
disable readdir_ra: 1m25.69s real 0m01.94s user 0m50.80s system
enable readdir_ra: 0m18.55s real 0m00.44s user 0m15.39s system
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
alloc_nid_failed and scan_nat_page can be called at the same time,
and we haven't protected add_free_nid and update_free_nid_bitmap
with the same nid_list_lock. That could lead to
Thread A Thread B
- __build_free_nids
- scan_nat_page
- add_free_nid
- alloc_nid_failed
- update_free_nid_bitmap
- update_free_nid_bitmap
scan_nat_page will clear the free bitmap since the nid is PREALLOC_NID,
but alloc_nid_failed needs to set the free bitmap. This results in
free nid with free bitmap cleared.
This patch update the bitmap under the same nid_list_lock in add_free_nid.
And use __GFP_NOFAIL to make sure to update status of free nid correctly.
Signed-off-by: Fan li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We forgot to remov memory footprint accounting of per-cpu type
variables, fix it.
Fixes: 35782b233f ("f2fs: remove percpu_count due to performance regression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
No need to read nat block if nat_block_bitmap is set.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
During mkfs, quota sysfiles have already occupied nid resource,
it needs to adjust remaining available nid count in kernel side.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This reverts commit 04e35f4495.
SELinux runs with secureexec for all non-"noatsecure" domain transitions,
which means lots of processes end up hitting the stack hard-limit change
that was introduced in order to fix a race with prlimit(). That race fix
will need to be redesigned.
Reported-by: Laura Abbott <labbott@redhat.com>
Reported-by: Tomáš Trnka <trnka@scm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With CONFIG_MTD=m and CONFIG_CRAMFS=y, we now get a link failure:
fs/cramfs/inode.o: In function `cramfs_mount': inode.c:(.text+0x220): undefined reference to `mount_mtd'
fs/cramfs/inode.o: In function `cramfs_mtd_fill_super':
inode.c:(.text+0x6d8): undefined reference to `mtd_point'
inode.c:(.text+0xae4): undefined reference to `mtd_unpoint'
This adds a more specific Kconfig dependency to avoid the broken
configuration.
Alternatively we could make CRAMFS itself depend on "MTD || !MTD" with a
similar result.
Fixes: 99c18ce580 ("cramfs: direct memory access support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs fixes from Al Viro:
"The alloc_super() one is a regression in this merge window, lazytime
thing is older..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
VFS: Handle lazytime in do_mount()
alloc_super(): do ->s_umount initialization earlier
ancient ext3 file system images. Also fix two xfstests failures, one
of which could cause a OOPS, plus an additional bug fix caught by fuzz
testing.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlo1y3EACgkQ8vlZVpUN
gaNFOQf/bMf6ynai1dGGRwef+UcT874NZ2Hqm+UqI6pxusz0ZeKWm8HWfPfg31Fa
o+OnUsZ7NXFBIHyfXKFJzdOgutjZ5eY0vMu+NrlyBdd6W+ZcHwn1PvQsLapFYvqK
Rt+8nWTKqtnksSfh0vyODmUYgItOULOPPepjnIPm/Pd0DinJwo0GY/8MzLkz4SpX
g6R60ou0ToEYNqBXAKIBnZ4aq8KWMtCMGcD270U5eAm/63Pt4riRwJbjITxZPAH1
wKzivP4Ce5ce8W2g2/6mFFlBFWvtlB491T+BsgHUEv3OLze+kYS2PcxQthhEmBR8
zeZ2o2/0tTxejE//cyJ4gCe3fYGRDg==
=xqLC
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Fix a regression which caused us to fail to interpret symlinks in very
ancient ext3 file system images.
Also fix two xfstests failures, one of which could cause an OOPS, plus
an additional bug fix caught by fuzz testing"
* tag 'ext4_for_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix crash when a directory's i_size is too small
ext4: add missing error check in __ext4_new_inode()
ext4: fix fdatasync(2) after fallocate(2) operation
ext4: support fast symlinks from ext3 file systems
Stable bugfixes:
- NFS: Avoid a BUG_ON() in nfs_commit_inode() by not waiting for a
commit in the case that there were no commit requests.
- SUNRPC: Fix a race in the receive code path
Other fixes:
- NFS: Fix a deadlock in nfs client initialization
- xprtrdma: Fix a performance regression for small IOs
-----BEGIN PGP SIGNATURE-----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=XhEC
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.15-3' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client fixes from Anna Schumaker:
"This has two stable bugfixes, one to fix a BUG_ON() when
nfs_commit_inode() is called with no outstanding commit requests and
another to fix a race in the SUNRPC receive codepath.
Additionally, there are also fixes for an NFS client deadlock and an
xprtrdma performance regression.
Summary:
Stable bugfixes:
- NFS: Avoid a BUG_ON() in nfs_commit_inode() by not waiting for a
commit in the case that there were no commit requests.
- SUNRPC: Fix a race in the receive code path
Other fixes:
- NFS: Fix a deadlock in nfs client initialization
- xprtrdma: Fix a performance regression for small IOs"
* tag 'nfs-for-4.15-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
SUNRPC: Fix a race in the receive code path
nfs: don't wait on commit in nfs_commit_inode() if there were no commit requests
xprtrdma: Spread reply processing over more CPUs
nfs: fix a deadlock in nfs client initialization
This reverts commits 5c9d2d5c26, c7da82b894, and e7fe7b5cae.
We'll probably need to revisit this, but basically we should not
complicate the get_user_pages_fast() case, and checking the actual page
table protection key bits will require more care anyway, since the
protection keys depend on the exact state of the VM in question.
Particularly when doing a "remote" page lookup (ie in somebody elses VM,
not your own), you need to be much more careful than this was. Dave
Hansen says:
"So, the underlying bug here is that we now a get_user_pages_remote()
and then go ahead and do the p*_access_permitted() checks against the
current PKRU. This was introduced recently with the addition of the
new p??_access_permitted() calls.
We have checks in the VMA path for the "remote" gups and we avoid
consulting PKRU for them. This got missed in the pkeys selftests
because I did a ptrace read, but not a *write*. I also didn't
explicitly test it against something where a COW needed to be done"
It's also not entirely clear that it makes sense to check the protection
key bits at this level at all. But one possible eventual solution is to
make the get_user_pages_fast() case just abort if it sees protection key
bits set, which makes us fall back to the regular get_user_pages() case,
which then has a vma and can do the check there if we want to.
We'll see.
Somewhat related to this all: what we _do_ want to do some day is to
check the PAGE_USER bit - it should obviously always be set for user
pages, but it would be a good check to have back. Because we have no
generic way to test for it, we lost it as part of moving over from the
architecture-specific x86 GUP implementation to the generic one in
commit e585513b76 ("x86/mm/gup: Switch GUP to the generic
get_user_page_fast() implementation").
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull overlayfs fixes from Miklos Szeredi:
- fix incomplete syncing of filesystem
- fix regression in readdir on ovl over 9p
- only follow redirects when needed
- misc fixes and cleanups
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: fix overlay: warning prefix
ovl: Use PTR_ERR_OR_ZERO()
ovl: Sync upper dirty data when syncing overlayfs
ovl: update ctx->pos on impure dir iteration
ovl: Pass ovl_get_nlink() parameters in right order
ovl: don't follow redirects if redirect_dir=off
The following deadlock can occur between a process waiting for a client
to initialize in while walking the client list during nfsv4 server trunking
detection and another process waiting for the nfs_clid_init_mutex so it
can initialize that client:
Process 1 Process 2
--------- ---------
spin_lock(&nn->nfs_client_lock);
list_add_tail(&CLIENTA->cl_share_link,
&nn->nfs_client_list);
spin_unlock(&nn->nfs_client_lock);
spin_lock(&nn->nfs_client_lock);
list_add_tail(&CLIENTB->cl_share_link,
&nn->nfs_client_list);
spin_unlock(&nn->nfs_client_lock);
mutex_lock(&nfs_clid_init_mutex);
nfs41_walk_client_list(clp, result, cred);
nfs_wait_client_init_complete(CLIENTA);
(waiting for nfs_clid_init_mutex)
Make sure nfs_match_client() only evaluates clients that have completed
initialization in order to prevent that deadlock.
This patch also fixes v4.0 trunking behavior by not marking the client
NFS_CS_READY until the clientid has been confirmed.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Merge misc fixes from Andrew Morton:
"17 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
arch: define weak abort()
mm, oom_reaper: fix memory corruption
kernel: make groups_sort calling a responsibility group_info allocators
mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()'
tools/slabinfo-gnuplot: force to use bash shell
kcov: fix comparison callback signature
mm/slab.c: do not hash pointers when debugging slab
mm/page_alloc.c: avoid excessive IRQ disabled times in free_unref_page_list()
mm/memory.c: mark wp_huge_pmd() inline to prevent build failure
scripts/faddr2line: fix CROSS_COMPILE unset error
Documentation/vm/zswap.txt: update with same-value filled page feature
exec: avoid gcc-8 warning for get_task_comm
autofs: fix careless error in recent commit
string.h: workaround for increased stack usage
mm/kmemleak.c: make cond_resched() rate-limiting more efficient
lib/rbtree,drm/mm: add rbtree_replace_node_cached()
include/linux/idr.h: add #include <linux/bug.h>
In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.
This patch:
- Make groups_sort globally visible.
- Move the call to groups_sort to the modifiers of group_info
- Remove the call to groups_sort from set_groups
Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker <thiago.becker@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-8 warns about using strncpy() with the source size as the limit:
fs/exec.c:1223:32: error: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess]
This is indeed slightly suspicious, as it protects us from source
arguments without NUL-termination, but does not guarantee that the
destination is terminated.
This keeps the strncpy() to ensure we have properly padded target
buffer, but ensures that we use the correct length, by passing the
actual length of the destination buffer as well as adding a build-time
check to ensure it is exactly TASK_COMM_LEN.
There are only 23 callsites which I all reviewed to ensure this is
currently the case. We could get away with doing only the check or
passing the right length, but it doesn't hurt to do both.
Link: http://lkml.kernel.org/r/20171205151724.1764896-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Aleksa Sarai <asarai@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit ecc0c469f2 ("autofs: don't fail mount for transient error") was
meant to replace an 'if' with a 'switch', but instead added the 'switch'
leaving the case in place.
Link: http://lkml.kernel.org/r/87zi6wstmw.fsf@notabene.neil.brown.name
Fixes: ecc0c469f2 ("autofs: don't fail mount for transient error")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NeilBrown <neilb@suse.com>
Cc: Ian Kent <raven@themaw.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conform two stray warning messages to the standard overlayfs: prefix.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
- Clean up duplicate includes
- Remove ancient 'no-alloc' crap code that occasionally caused hard fs
shutdowns due to lack of proper space reservations
- Fix regression in FIEMAP behavior when reporting xattr extents
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=cmic
-----END PGP SIGNATURE-----
Merge tag 'xfs-4.15-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"Here are a few more bug fixes & cleanups for 4.15-rc4:
- clean up duplicate includes
- remove ancient 'no-alloc' crap code that occasionally caused hard
fs shutdowns due to lack of proper space reservations
- fix regression in FIEMAP behavior when reporting xattr extents"
* tag 'xfs-4.15-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: make iomap_begin functions trim iomaps consistently
xfs: remove "no-allocation" reservations for file creations
fs: xfs: remove duplicate includes
On a ppc64 machine, when mounting a fuzzed ext2 image (generated by
fsfuzzer) the following call trace is seen,
VFS: brelse: Trying to free free buffer
WARNING: CPU: 1 PID: 6913 at /root/repos/linux/fs/buffer.c:1165 .__brelse.part.6+0x24/0x40
.__brelse.part.6+0x20/0x40 (unreliable)
.ext4_find_entry+0x384/0x4f0
.ext4_lookup+0x84/0x250
.lookup_slow+0xdc/0x230
.walk_component+0x268/0x400
.path_lookupat+0xec/0x2d0
.filename_lookup+0x9c/0x1d0
.vfs_statx+0x98/0x140
.SyS_newfstatat+0x48/0x80
system_call+0x58/0x6c
This happens because the directory that ext4_find_entry() looks up has
inode->i_size that is less than the block size of the filesystem. This
causes 'nblocks' to have a value of zero. ext4_bread_batch() ends up not
reading any of the directory file's blocks. This renders the entries in
bh_use[] array to continue to have garbage data. buffer_uptodate() on
bh_use[0] can then return a zero value upon which brelse() function is
invoked.
This commit fixes the bug by returning -ENOENT when the directory file
has no associated blocks.
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fix ptr_ret.cocci warnings:
fs/overlayfs/overlayfs.h:179:11-17: WARNING: PTR_ERR_OR_ZERO can be used
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Generated by: scripts/coccinelle/api/ptr_ret.cocci
Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When executing filesystem sync or umount on overlayfs,
dirty data does not get synced as expected on upper filesystem.
This patch fixes sync filesystem method to keep data consistency
for overlayfs.
Signed-off-by: Chengguang Xu <cgxu@mykernel.net>
Fixes: e593b2bf51 ("ovl: properly implement sync_filesystem()")
Cc: <stable@vger.kernel.org> #4.11
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This fixes a regression with readdir of impure dir in overlayfs
that is shared to VM via 9p fs.
Reported-by: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Fixes: 4edb83bb10 ("ovl: constant d_ino for non-merge dirs")
Cc: <stable@vger.kernel.org> #4.14
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Tested-by: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Right now we seem to be passing index as "lowerdentry" and origin.dentry
as "upperdentry". IIUC, we should pass these parameters in reversed order
and this looks like a bug.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Amir Goldstein <amir73il@gmail.com>
Fixes: caf70cb2ba ("ovl: cleanup orphan index entries")
Cc: <stable@vger.kernel.org> #v4.13
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Overlayfs is following redirects even when redirects are disabled. If this
is unintentional (probably the majority of cases) then this can be a
problem. E.g. upper layer comes from untrusted USB drive, and attacker
crafts a redirect to enable read access to otherwise unreadable
directories.
If "redirect_dir=off", then turn off following as well as creation of
redirects. If "redirect_dir=follow", then turn on following, but turn off
creation of redirects (which is what "redirect_dir=off" does now).
This is a backward incompatible change, so make it dependent on a config
option.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
It's possible for ext4_get_acl() to return an ERR_PTR. So we need to
add a check for this case in __ext4_new_inode(). Otherwise on an
error we can end up oops the kernel.
This was getting triggered by xfstests generic/388, which is a test
which exercises the shutdown code path.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
HPFS does not set SB_I_VERSION and does not use the i_version counter
internally.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Reviewed-by: Mikulas Patocka <mikulas@twibright.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----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=YaZE
-----END PGP SIGNATURE-----
Merge tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"This contains a few fixes (error handling, quota leak, FUA vs
nobarrier mount option).
There's one one worth mentioning separately - an off-by-one fix that
leads to overwriting first byte of an adjacent page with 0, out of
bounds of the memory allocated by an ioctl. This is under a privileged
part of the ioctl, can be triggerd in some subvolume layouts"
* tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: Fix possible off-by-one in btrfs_search_path_in_tree
Btrfs: disable FUA if mounted with nobarrier
btrfs: fix missing error return in btrfs_drop_snapshot
btrfs: handle errors while updating refcounts in update_ref_for_cow
btrfs: Fix quota reservation leak on preallocated files
Since commit e462ec50cb ("VFS: Differentiate mount flags (MS_*) from
internal superblock flags") the lazytime mount option doesn't get passed
on anymore.
Fix the issue by handling the option in do_mount().
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Historically, the XFS iomap_begin function only returned mappings for
exactly the range queried, i.e. it doesn't do XFS_BMAPI_ENTIRE lookups.
The current vfs iomap consumers are only set up to deal with trimmed
mappings. xfs_xattr_iomap_begin does BMAPI_ENTIRE lookups, which is
inconsistent with the current iomap usage. Remove the flag so that both
iomap_begin functions behave the same way.
FWIW this also fixes a behavioral regression in xattr FIEMAP that was
introduced in 4.8 wherein attr fork extents are no longer trimmed like
they used to be.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.
Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
It's a user pointer, and while the permissions of the file are pretty
questionable (should it really be readable to everybody), hashing the
pointer isn't going to be the solution.
We should take a closer look at more of the /proc/<pid> file permissions
in general. Sure, we do want many of them to often be readable (for
'ps' and friends), but I think we should probably do a few conversions
from S_IRUGO to S_IRUSR.
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The name char array passed to btrfs_search_path_in_tree is of size
BTRFS_INO_LOOKUP_PATH_MAX (4080). So the actual accessible char indexes
are in the range of [0, 4079]. Currently the code uses the define but this
represents an off-by-one.
Implications:
Size of btrfs_ioctl_ino_lookup_args is 4096, so the new byte will be
written to extra space, not some padding that could be provided by the
allocator.
btrfs-progs store the arguments on stack, but kernel does own copy of
the ioctl buffer and the off-by-one overwrite does not affect userspace,
but the ending 0 might be lost.
Kernel ioctl buffer is allocated dynamically so we're overwriting
somebody else's memory, and the ioctl is privileged if args.objectid is
not 256. Which is in most cases, but resolving a subvolume stored in
another directory will trigger that path.
Before this patch the buffer was one byte larger, but then the -1 was
not added.
Fixes: ac8e9819d7 ("Btrfs: add search and inode lookup ioctls")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ added implications ]
Signed-off-by: David Sterba <dsterba@suse.com>
I was seeing disk flushes still happening when I mounted a Btrfs
filesystem with nobarrier for testing. This is because we use FUA to
write out the first super block, and on devices without FUA support, the
block layer translates FUA to a flush. Even on devices supporting true
FUA, using FUA when we asked for no barriers is surprising.
Fixes: 387125fc72 ("Btrfs: fix barrier flushes")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If btrfs_del_root fails in btrfs_drop_snapshot, we'll pick up the
error but then return 0 anyway due to mixing err and ret.
Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
Cc: <stable@vger.kernel.org> # v3.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit fb235dc06f (btrfs: qgroup: Move half of the qgroup
accounting time out of commit trans) the assumption that
btrfs_add_delayed_{data,tree}_ref can only return 0 or -ENOMEM has
been false. The qgroup operations call into btrfs_search_slot
and friends and can now return the full spectrum of error codes.
Fortunately, the fix here is easy since update_ref_for_cow failing
is already handled so we just need to bail early with the error
code.
Fixes: fb235dc06f (btrfs: qgroup: Move half of the qgroup accounting ...)
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit c6887cd111 ("Btrfs: don't do nocow check unless we have to")
changed the behavior of __btrfs_buffered_write() so that it first tries
to get a data space reservation, and then skips the relatively expensive
nocow check if the reservation succeeded.
If we have quotas enabled, the data space reservation also includes a
quota reservation. But in the rewrite case, the space has already been
accounted for in qgroups. So btrfs_check_data_free_space() increases
the quota reservation, but it never gets decreased when the data
actually gets written and overwrites the pre-existing data. So we're
left with both the qgroup and qgroup reservation accounting for the same
space.
This commit adds the missing btrfs_qgroup_free_data() call in the case
of BTRFS_ORDERED_PREALLOC extents.
Fixes: c6887cd111 ("Btrfs: don't do nocow check unless we have to")
Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
cifs.ko makes DFS queries regardless of the type of the server and
non-DFS servers are common. This often results in superfluous logging of
non-critical errors.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>