The KCOV selftest enables coverage by setting current->kcov_mode to
KCOV_MODE_TRACE_PC without installing a coverage area. If an interrupt
records coverage in that window, the access should fault and expose the
bug.
When building for QEMU raspi0 (Raspberry Pi Zero, ARMv6, CONFIG_CPU_V6K=y,
CONFIG_CURRENT_POINTER_IN_TPIDRURO=y) with GCC 13.3.0, the store that
enables the mode is removed. The generated kcov_init() code only stores
zero after the wait loop:
mrc 15, 0, r3, cr13, cr0, {3}
str r4, [r3, #2028]
where r4 is zero. There is no store of KCOV_MODE_TRACE_PC before the
loop, so the selftest reports success without exercising coverage.
Use WRITE_ONCE() for the temporary mode stores. With the same compiler
and config, kcov_init() contains the intended mode store:
mov r3, #2
mrc 15, 0, r2, cr13, cr0, {3}
str r3, [r2, #2028]
Now that the KCOV selftest is actually executed, it may expose KCOV
instrumentation issues depending on the kernel config. That is expected
for a selftest that was intended to catch coverage from interrupt paths.
Link: https://lore.kernel.org/20260526114715.38280-1-kmehltretter@gmail.com
Fixes: 6cd0dd934b ("kcov: Add interrupt handling self test")
Assisted-by: Codex:gpt-5
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The locking_state debugfs iterator snapshots struct ocfs2_lock_res by
value under ocfs2_dlm_tracking_lock and later formats that copy in
ocfs2_dlm_seq_show(). That is fine for the inline fields, but the
userspace fsdlm stack stores the LVB through lksb_fsdlm.sb_lvbptr. Once
the iterator drops the tracking lock, a copied non-NULL sb_lvbptr still
points into the original lockres owner, so teardown can free that
container before the debugfs dump walks the raw LVB bytes.
Rebase the copied sb_lvbptr to the copied l_lksb before dumping the raw
LVB. The seq snapshot already carries the inline LVB storage reserved in
struct ocfs2_dlm_lksb, so the debugfs reader can dump the copied bytes
without borrowing the original lockres lifetime.
The buggy scenario involves two paths, with each column showing the order
within that path:
locking_state reader: lockres teardown:
1. ocfs2_dlm_seq_start()/next() 1. file release or another owner
copies struct ocfs2_lock_res teardown reaches
2. ocfs2_dlm_seq_show() formats ocfs2_lock_res_free()
the copied row 2. the lockres is removed from the
3. ocfs2_dlm_lvb() follows the tracking list
copied sb_lvbptr 3. the owner frees the original
lockres container
Validation reproduced this kernel report:
KASAN slab-use-after-free in ocfs2_dlm_seq_show+0x1bd/0x430
RIP: 0033:0x7f8ec4b1e29d
The buggy address belongs to the object at ffff88810a1e0800 which belongs
to the cache kmalloc-1k of size 1024
The buggy address is located 368 bytes inside of freed 1024-byte region
[ffff88810a1e0800, ffff88810a1e0c00)
Read of size 1
Call trace:
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x630
ocfs2_dlm_seq_show+0x1bd/0x430 (fs/ocfs2/dlmglue.c:3137)
srso_alias_return_thunk+0x5/0xfbef5
__virt_addr_valid+0x19f/0x330
kasan_report+0xe0/0x110
seq_read_iter+0x29d/0x790
seq_read+0x20a/0x280
find_held_lock+0x2b/0x80
rcu_read_unlock+0x18/0x70
full_proxy_read+0x9e/0xd0
vfs_read+0x12c/0x590
ksys_read+0xd2/0x170
do_user_addr_fault+0x65a/0x890
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Allocated by task stack:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
__kasan_kmalloc+0xaa/0xb0
ocfs2_file_open+0x13e/0x300
do_dentry_open+0x233/0x7f0
vfs_open+0x5a/0x1b0
path_openat+0x66d/0x1540
do_file_open+0x186/0x2b0
do_sys_openat2+0xce/0x150
__x64_sys_openat+0xd0/0x140
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task stack:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x5f/0x80
kfree+0x313/0x590
ocfs2_file_release+0x138/0x260
__fput+0x1df/0x4b0
fput_close_sync+0xd2/0x170
__x64_sys_close+0x55/0x90
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Link: https://lore.kernel.org/20260525041726.4112882-1-rollkingzzc@gmail.com
Fixes: cf4d8d75d8 ("ocfs2: add fsdlm to stackglue")
Assisted-by: Codex:gpt-5.5
Signed-off-by: Zhang Cen <rollkingzzc@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When debugging RCU stall cases, usually all CPUs will respond to the NMI
and print out the backtrace. But in some nasty or hardware related cases,
some CPUs may fail to respond in 10 seconds, and very likely this is sign
of severe issues.
Paul McKenney has implemented the NMI backtrace stall check for x86, and
for other architectures, it should be also helpful to at least print out
those CPUs which failed to repond to the NMI, so that users can get an
early heads-up for possible CPU hard stall.
[feng.tang@linux.alibaba.com: avoid hard-coding "10" in two places and in a comment]
Link: https://lore.kernel.org/ag-1ciG0FSomBf7q@U-2FWC9VHC-2323.local
[akpm@linux-foundation.org: use __stringify()]
Link: https://lore.kernel.org/20260521030336.92172-1-feng.tang@linux.alibaba.com
Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
uuid_kunit currently exercises only guid_parse() and uuid_parse() (plus
their invalid-input paths). The four random generators exported from
lib/uuid.c -- generate_random_uuid(), generate_random_guid(), uuid_gen()
and guid_gen() -- have no direct kunit coverage.
Random output cannot be compared against a fixed expected value, but RFC
4122 section 4.4 specifies two invariants that any version-4 random
UUID/GUID must satisfy:
- version 4 in the high nibble of the version byte
(byte 6 in the wire uuid_t layout, byte 7 in the byte-swapped
guid_t layout);
- variant DCE 1.1 (binary 10x) in the high bits of byte 8.
Add four test cases that invoke each generator several times and verify
these bit patterns hold. The same checks catch a regression in either the
mask/OR sequence in the generators or the layout constants. Run the loop
a handful of times to cover the small but non-zero chance that an unmasked
random byte happens to satisfy the version/variant pattern by accident on
a single call.
Link: https://lore.kernel.org/20260516120915.40544-1-sozdayvek@gmail.com
Signed-off-by: Stepan Ionichev <sozdayvek@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <david@davidgow.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
On a volume mounted without OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC, a
non-inline regular file with non-zero i_size and zero i_clusters is
structurally malformed: the extent map declares no allocated clusters yet
the size header claims content exists. Keep rejecting that shape, but
express it through a shared predicate so the same invariant is available
to normal inode reads and online filecheck.
The same zero-cluster shape is also malformed for non-inline directories.
ocfs2 directory growth allocates backing storage before advancing i_size,
and ocfs2_dir_foreach_blk_el() later walks until ctx->pos reaches
i_size_read(inode). A forged directory dinode with a huge i_size and no
clusters would repeatedly fail on holes while advancing through the
claimed size.
Sparse regular files remain exempt: on sparse-alloc volumes, truncate can
legitimately grow i_size without allocating clusters. System inodes and
inline-data dinodes also retain their separate storage rules.
Mirror the check in ocfs2_filecheck_validate_inode_block() as well.
filecheck reports through its own error namespace, so malformed
size/cluster state is logged as a filecheck invalid-inode result rather
than via ocfs2_error(), but it must not proceed into
ocfs2_populate_inode().
Link: https://lore.kernel.org/20260519110404.1803902-4-michael.bommarito@gmail.com
Fixes: b657c95c11 ("ocfs2: Wrap inode block reads in a dedicated function.")
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://sashiko.dev/#/patchset/20260517111015.3187935-1-michael.bommarito%40gmail.com
Assisted-by: Claude:claude-opus-4-7
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
id1.dev1.i_rdev is the device-number arm of the ocfs2_dinode id1 union.
It is only meaningful for character and block device inodes. For any
other user-visible file type the on-disk value must be zero.
ocfs2_populate_inode() currently copies id1.dev1.i_rdev into inode->i_rdev
before the S_IFMT switch decides whether the inode is a special file. A
non-device inode with a non-zero i_rdev can therefore publish stale or
attacker-controlled device state into the in-core inode.
System inodes legitimately use other arms of the same union, so keep the
cross-check restricted to non-system inodes. Factor that predicate into a
helper and use it in both the normal validator and online filecheck path;
filecheck reports the malformed dinode through
OCFS2_FILECHECK_ERR_INVALIDINO instead of ocfs2_error().
Link: https://lore.kernel.org/20260519110404.1803902-3-michael.bommarito@gmail.com
Fixes: b657c95c11 ("ocfs2: Wrap inode block reads in a dedicated function.")
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Assisted-by: Claude:claude-opus-4-7
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ocfs2: harden inode validators against forged metadata", v2.
This series adds three structural checks to OCFS2 dinode validation so
malformed on-disk fields are rejected before ocfs2_populate_inode() copies
them into the in-core inode.
The checks cover:
- i_mode values whose type bits do not name a canonical POSIX file
type;
- non-device dinodes whose id1.dev1.i_rdev field is non-zero; and
- non-inline dinodes that claim non-zero i_size while i_clusters is
zero, covering directories unconditionally and regular files on
non-sparse volumes.
The normal read path reports these through ocfs2_error(), matching the
existing suballoc-slot, inline-data, chain-list, and refcount checks. The
online filecheck path uses the same structural predicates but keeps its
own reporting contract, returning OCFS2_FILECHECK_ERR_INVALIDINO instead
of calling ocfs2_error().
This patch (of 3):
ocfs2_validate_inode_block() currently accepts any non-zero i_mode value.
ocfs2_populate_inode() then copies that mode verbatim into inode->i_mode
and dispatches on i_mode & S_IFMT to the file/dir/symlink/special_file
iops; an unrecognised type falls through to ocfs2_special_file_iops and
init_special_inode().
Reject dinodes whose type bits do not name one of the seven canonical
POSIX file types. Use fs_umode_to_ftype(), the same generic file-type
conversion helper OCFS2 already uses for directory entries, so the
accepted inode type set matches the kernel file-type vocabulary instead of
open-coding a local switch.
Apply the same structural check to the online filecheck read path.
filecheck keeps its own error namespace, so it reports malformed i_mode
through the filecheck logger and OCFS2_FILECHECK_ERR_INVALIDINO instead of
calling ocfs2_error(), but it must not allow a malformed dinode to proceed
into ocfs2_populate_inode().
Link: https://lore.kernel.org/20260519110404.1803902-1-michael.bommarito@gmail.com
Link: https://lore.kernel.org/20260519110404.1803902-2-michael.bommarito@gmail.com
Fixes: b657c95c11 ("ocfs2: Wrap inode block reads in a dedicated function.")
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://sashiko.dev/#/patchset/20260517111015.3187935-1-michael.bommarito%40gmail.com
Assisted-by: Claude:claude-opus-4-7
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "cleanup the RAID6 P/Q library", v3.
This series cleans up the RAID6 P/Q library to match the recent updates to
the RAID 5 XOR library and other CRC/crypto libraries. This includes
providing properly documented external interfaces, hiding the internals,
using static_call instead of indirect calls and turning the user space
test suite into an in-kernel kunit test which is also extended to improve
coverage.
Note that this changes registration so that non-priority algorithms are
not registered, which greatly helps with the benchmark time at boot time.
I'd like to encourage all architecture maintainers to see if they can
further optimized this by registering as few as possible algorithms when
there is a clear benefit in optimized or more unrolled implementations.
This patch (of 18):
Currently the raid6 code can be compiled as userspace code to run the test
suite. Convert that to be a kunit case with minimal changes to avoid
mutating global state so that we can drop this requirement.
Note that this is not a good kunit test case yet and will need a lot more
work, but that is deferred until the raid6 code is moved to it's new
place, which is easier if the userspace makefile doesn't need adjustments
for the new location first.
Link: https://lore.kernel.org/20260518051804.462141-1-hch@lst.de
Link: https://lore.kernel.org/20260518051804.462141-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org> # kunit only on arm64
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Li Nan <linan122@huawei.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Song Liu <song@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Allow the same userspace thread to simultaneously collect normal coverage
in syscall context (KCOV_ENABLE) and remote coverage of asynchronous work
created by the thread (KCOV_REMOTE_ENABLE). With this, remote KCOV
coverage becomes useful for generic fuzzing and not just fuzzing of
specific data injection interfaces.
This requires that the task_struct::kcov_* fields are separated into ones
that are used by the task that generates coverage, and ones that are used
by the task that requested remote coverage. To split this up:
- Split task_struct::kcov into kcov and kcov_remote. kcov_task_exit() now
has to clean up both separately.
- Only use task_struct::kcov_mode on the task that generates coverage.
- Only reset task_struct::kcov_handle on the task that requested remote
coverage.
After this change, fields used by the task that generates coverage are:
- kcov_mode
- kcov_size
- kcov_area
- kcov
- kcov_sequence
- kcov_softirq
Fields used by the task that requested remote coverage are:
- kcov_remote
- kcov_handle
[jannh@google.com: remove unused constant KCOV_MODE_REMOTE, per Dmitry]
Link: https://lore.kernel.org/20260515-kcov-simultaneous-remote-v2-1-56fde1cfa509@google.com
[jannh@google.com: update documentation on remote coverage collection]
Link: https://lore.kernel.org/20260519-kcov-docs-v1-1-5bb22f4cb20c@google.com
[jannh@google.com: move and reword sentence on simultaneous normal/remote collection
Link: https://lore.kernel.org/20260520-kcov-docs-v2-1-819f78778763@google.com
Link: https://lore.kernel.org/20260505-kcov-simultaneous-remote-v1-1-a670ba7cefd2@google.com
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Improve the overall code quality of lib/bug.c by:
- Reformatting the main documentation block to follow the standard
kernel multi-line comment style.
- Replacing 'unsigned' with the preferred 'unsigned int'.
- Converting legacy printk() calls to modern pr_warn() and pr_info()
macros to include proper facility levels and satisfy checkpatch.
Link: https://lore.kernel.org/20260504201607.56932-1-lucasp.linux@gmail.com
Signed-off-by: Lucas Poupeau <lucasp.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[BUG]
A corrupt inline xattr header can make
ocfs2_has_inline_xattr_value_outside() walk xh_count from an unchecked
header while refcount-tree teardown decides whether inline xattrs still
point outside the inode body.
[CAUSE]
ocfs2_has_inline_xattr_value_outside() still computed the inline header
directly from di->i_xattr_inline_size and immediately iterated xh_count.
That is the same unchecked metadata boundary as the ibody lookup bug.
[FIX]
Reuse the shared inline-header helper before iterating xh_count. Because
this helper returns a boolean-style answer to its caller, treat a corrupt
header conservatively as "has outside values" instead of walking it.
Link: https://lore.kernel.org/20260508085914.61647-3-gality369@gmail.com
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Zixuan Fu <r33s3n6@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ocfs2: validate inline xattr header consumers".
Corrupt i_xattr_inline_size can move the computed inode-body xattr header
outside the dinode block. Several OCFS2 paths then trust xh_count or
xattr entry geometry from that unchecked header.
The reported KASAN splat hits the ibody lookup path:
BUG: KASAN: use-after-free in ocfs2_xattr_find_entry+0x37b/0x3a0
ocfs2_xattr_ibody_get()
ocfs2_xattr_get_nolock()
ocfs2_calc_xattr_init()
The same unchecked header derivation also exists in the outside-value
probe, ibody remove, inline refcount attach, and inline reflink paths.
This series factors the existing ibody list validation into a shared
helper and then converts the remaining inline-header consumers one at a
time.
Patch layout:
1. validate ibody get/find and reuse the helper in ibody list
2. validate the outside-value probe
3. validate ibody remove
4. validate inline refcount attach
5. validate inline reflink
This patch (of 5):
[BUG]
mknodat() can read past the end of a dinode block when ACL inheritance
walks a corrupted inode-body xattr header. Another report shows the same
unchecked lookup later faulting in the VFS open path after create
returns a garbage status.
KASAN: use-after-free in
ocfs2_xattr_find_entry+0x37b/0x3a0 fs/ocfs2/xattr.c:1078
Read of size 2 at addr ffff88801c520300 by task syz.0.10/360
Trace:
...
ocfs2_xattr_find_entry+0x37b/0x3a0 fs/ocfs2/xattr.c:1078
ocfs2_xattr_ibody_get fs/ocfs2/xattr.c:1178 [inline]
ocfs2_xattr_get_nolock+0x2ee/0x1110 fs/ocfs2/xattr.c:1309
ocfs2_calc_xattr_init+0x716/0xac0 fs/ocfs2/xattr.c:628
ocfs2_mknod+0x935/0x2400 fs/ocfs2/namei.c:333
ocfs2_create+0x158/0x390 fs/ocfs2/namei.c:676
vfs_create fs/namei.c:3493 [inline]
vfs_create+0x445/0x6f0 fs/namei.c:3477
do_mknodat+0x2d8/0x5e0 fs/namei.c:4372
__do_sys_mknodat fs/namei.c:4400 [inline]
__se_sys_mknodat fs/namei.c:4397 [inline]
__x64_sys_mknodat+0xb6/0xf0 fs/namei.c:4397
...
Another report:
BUG: unable to handle page fault for address: fffffbfff3e40ec0
RIP: 0010:__d_entry_type include/linux/dcache.h:414 [inline]
RIP: 0010:d_can_lookup include/linux/dcache.h:429 [inline]
RIP: 0010:d_is_dir include/linux/dcache.h:439 [inline]
RIP: 0010:path_openat+0xe2f/0x2ce0 fs/namei.c:4134
Trace:
...
do_filp_open+0x1f6/0x430 fs/namei.c:4161
do_sys_openat2+0x117/0x1c0 fs/open.c:1437
__x64_sys_openat+0x15b/0x220 fs/open.c:1463
...
[CAUSE]
ocfs2_xattr_ibody_list() already validates the inline xattr size and
entry count, but ocfs2_xattr_ibody_get() and ocfs2_xattr_ibody_find()
still derive the inline header directly from di->i_xattr_inline_size and
then trust xh_count. A corrupted inline size or entry count can therefore
move the computed header outside the dinode block before get/find start
walking it. That can either make ocfs2_xattr_find_entry() dereference
xs->header->xh_count outside the block or make ocfs2_xattr_get_nolock()
bubble a garbage status back through ocfs2_calc_xattr_init() into the
create/open path.
[FIX]
Factor the existing ibody header geometry checks into a shared helper.
Use it in ocfs2_xattr_ibody_get() and ocfs2_xattr_ibody_find(), and have
ocfs2_xattr_ibody_list() reuse the same helper instead of open-coding
the validation. Reject corrupt ibody metadata with -EFSCORRUPTED before
the lookup path can walk bogus xattr geometry or return a garbage status.
Link: https://lore.kernel.org/20260508085914.61647-1-gality369@gmail.com
Link: https://lore.kernel.org/20260508085914.61647-2-gality369@gmail.com
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: Zixuan Fu <r33s3n6@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[BUG]
A fuzzed OCFS2 image can corrupt the current slot journal dinode while
mount is still in progress. The mount path first reports the invalid
journal block and then crashes in shutdown:
kernel BUG at fs/ocfs2/journal.c:1034!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:ocfs2_journal_toggle_dirty+0x2d6/0x340 fs/ocfs2/journal.c:1034
Call Trace:
ocfs2_journal_shutdown+0x414/0xc30 fs/ocfs2/journal.c:1116
ocfs2_mount_volume fs/ocfs2/super.c:1785 [inline]
ocfs2_fill_super+0x30a9/0x3cd0 fs/ocfs2/super.c:1083
get_tree_bdev_flags+0x38b/0x640 fs/super.c:1698
get_tree_bdev+0x24/0x40 fs/super.c:1721
ocfs2_get_tree+0x21/0x30 fs/ocfs2/super.c:1184
vfs_get_tree+0x9a/0x370 fs/super.c:1758
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3642 [inline]
do_new_mount fs/namespace.c:3718 [inline]
path_mount+0x5b8/0x1ea0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__x64_sys_mount+0x282/0x320 fs/namespace.c:4206
...
[CAUSE]
ocfs2_journal_toggle_dirty() used to return -EIO when journal->j_bh no
longer contained a valid dinode, because the startup and shutdown paths
already handled that failure. Commit 10995aa245
("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.") changed
the check to a BUG_ON() under the assumption that the journal dinode had
already been validated. That turns an unexpected invalid journal dinode
during mount teardown into a kernel crash instead of a normal mount
failure.
[FIX]
Replace the BUG_ON() with WARN_ON() and return -EIO. This keeps the
invariant warning for debugging, but restores the original behavior of
failing startup or shutdown cleanly instead of panicking the kernel.
Link: https://lore.kernel.org/20260512024115.4036371-1-gality369@gmail.com
Fixes: 10995aa245 ("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.")
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
