commit acf943e976 upstream.
When orphan file feature is enabled, inode can be tracked as orphan
either in the standard orphan list or in the orphan file. The first can
be tested by checking ei->i_orphan list head, the second is recorded by
EXT4_STATE_ORPHAN_FILE inode state flag. There are several places where
we want to check whether inode is tracked as orphan and only some of
them properly check for both possibilities. Luckily the consequences are
mostly minor, the worst that can happen is that we track an inode as
orphan although we don't need to and e2fsck then complains (resulting in
occasional ext4/307 xfstest failures). Fix the problem by introducing a
helper for checking whether an inode is tracked as orphan and use it in
appropriate places.
Fixes: 4a79a98c7b ("ext4: Improve scalability of ext4 orphan file handling")
Cc: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Message-ID: <20250925123038.20264-2-jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d8b6dc9256 upstream.
This parameter set the maximum number of connections per ip address.
The default is 8.
Cc: stable@vger.kernel.org
Fixes: c0d41112f1 ("ksmbd: extend the connection limiting mechanism to support IPv6")
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 88daf2f448 upstream.
If client doesn't negotiate with SMB3.1.1 POSIX Extensions,
then proper error code won't be returned due to overwriting.
Return error immediately.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Signed-off-by: Matvey Kovalev <matvey.kovalev@ispras.ru>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 305853cce3 upstream.
The 'sess->rpc_handle_list' XArray manages RPC handles within a ksmbd
session. Access to this list is intended to be protected by
'sess->rpc_lock' (an rw_semaphore). However, the locking implementation was
flawed, leading to potential race conditions.
In ksmbd_session_rpc_open(), the code incorrectly acquired only a read lock
before calling xa_store() and xa_erase(). Since these operations modify
the XArray structure, a write lock is required to ensure exclusive access
and prevent data corruption from concurrent modifications.
Furthermore, ksmbd_session_rpc_method() accessed the list using xa_load()
without holding any lock at all. This could lead to reading inconsistent
data or a potential use-after-free if an entry is concurrently removed and
the pointer is dereferenced.
Fix these issues by:
1. Using down_write() and up_write() in ksmbd_session_rpc_open()
to ensure exclusive access during XArray modification, and ensuring
the lock is correctly released on error paths.
2. Adding down_read() and up_read() in ksmbd_session_rpc_method()
to safely protect the lookup.
Fixes: a1f46c99d9 ("ksmbd: fix use-after-free in ksmbd_session_rpc_open")
Fixes: b685757c7b ("ksmbd: Implements sess->rpc_handle_list as xarray")
Cc: stable@vger.kernel.org
Signed-off-by: Yunseong Kim <ysk@kzalloc.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3bd5e45c2c upstream.
When parsing Allocation Extent Descriptor, lengthAllocDescs comes from
on-disk data and must be validated against the block size. Crafted or
corrupted images may set lengthAllocDescs so that the total descriptor
length (sizeof(allocExtDesc) + lengthAllocDescs) exceeds the buffer,
leading udf_update_tag() to call crc_itu_t() on out-of-bounds memory and
trigger a KASAN use-after-free read.
BUG: KASAN: use-after-free in crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60
Read of size 1 at addr ffff888041e7d000 by task syz-executor317/5309
CPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60
udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261
udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179
extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46
udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106
udf_release_file+0xc1/0x120 fs/udf/file.c:185
__fput+0x23f/0x880 fs/file_table.c:431
task_work_run+0x24f/0x310 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xa2f/0x28e0 kernel/exit.c:939
do_group_exit+0x207/0x2c0 kernel/exit.c:1088
__do_sys_exit_group kernel/exit.c:1099 [inline]
__se_sys_exit_group kernel/exit.c:1097 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Validate the computed total length against epos->bh->b_size.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Reported-by: syzbot+8743fca924afed42f93e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=8743fca924afed42f93e
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Larshin Sergey <Sergey.Larshin@kaspersky.com>
Link: https://patch.msgid.link/20250922131358.745579-1-Sergey.Larshin@kaspersky.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 74058c0a9f upstream.
Syzkaller reports a "KMSAN: uninit-value in squashfs_get_parent" bug.
This is caused by open_by_handle_at() being called with a file handle
containing an invalid parent inode number. In particular the inode number
is that of a symbolic link, rather than a directory.
Squashfs_get_parent() gets called with that symbolic link inode, and
accesses the parent member field.
unsigned int parent_ino = squashfs_i(inode)->parent;
Because non-directory inodes in Squashfs do not have a parent value, this
is uninitialised, and this causes an uninitialised value access.
The fix is to initialise parent with the invalid inode 0, which will cause
an EINVAL error to be returned.
Regular inodes used to share the parent field with the block_list_start
field. This is removed in this commit to enable the parent field to
contain the invalid inode number 0.
Link: https://lkml.kernel.org/r/20250918233308.293861-1-phillip@squashfs.org.uk
Fixes: 122601408d ("Squashfs: export operations")
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: syzbot+157bdef5cf596ad0da2c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68cc2431.050a0220.139b6.0001.GAE@google.com/
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 25ba2b84c3 ]
Add nfsd_file_dio_alignment and use it to avoid issuing misaligned IO
using O_DIRECT. Any misaligned DIO falls back to using buffered IO.
Because misaligned DIO is now handled safely, remove the nfs modparam
'localio_O_DIRECT_semantics' that was added to require users opt-in to
the requirement that all O_DIRECT be properly DIO-aligned.
Also, introduce nfs_iov_iter_aligned_bvec() which is a variant of
iov_iter_aligned_bvec() that also verifies the offset associated with
an iov_iter is DIO-aligned. NOTE: in a parallel effort,
iov_iter_aligned_bvec() is being removed along with
iov_iter_is_aligned().
Lastly, add pr_info_ratelimited if underlying filesystem returns
-EINVAL because it was made to try O_DIRECT for IO that is not
DIO-aligned (shouldn't happen, so its best to be louder if it does).
Fixes: 3feec68563 ("nfs/localio: add direct IO enablement with sync and async IO support")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d11f6cd1bb ]
Use STATX_DIOALIGN and STATX_DIO_READ_ALIGN to get DIO alignment
attributes from the underlying filesystem and store them in the
associated nfsd_file. This is done when the nfsd_file is first
opened for each regular file.
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Stable-dep-of: 25ba2b84c3 ("nfs/localio: avoid issuing misaligned IO using O_DIRECT")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8f45f08933 ]
user_cluster_disconnect() frees "conn->cc_private" which is "lc" but then
the error handling frees "lc" a second time. Set "lc" to NULL on this
path to avoid a double free.
Link: https://lkml.kernel.org/r/aNKDz_7JF7aycZ0k@stanley.mountain
Fixes: c994c2ebdb ("ocfs2: use the new DLM operation callbacks while requesting new lockspace")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.de>
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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 20a8e0454d ]
Commit 21aa65bf82 ("mm: remove callers of pfn_t functionality")
incorrectly replaced the pfn with the physical address when calling
vmf_insert_mixed(). Instead the phys_to_pfn_t() call should have been
replaced with PHYS_PFN().
Found by inspection after a similar issue was noted in fuse virtio_fs.
Link: https://lkml.kernel.org/r/20250923005333.3165032-1-apopple@nvidia.com
Fixes: 21aa65bf82 ("mm: remove callers of pfn_t functionality")
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Haiyue Wang <haiyuewa@163.com>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 191512355e ]
When the client max_resp_sz is larger than what the server encodes in
its reply, the nfs4_verify_back_channel_attrs() check fails and this
causes nfs4_proc_create_session() to fail, in cases where the client
page size is larger than that of the server and the server does not want
to negotiate upwards.
While this is not a problem with the linux nfs server that will reflect
the proposed value in its reply irrespective of the local page size,
other nfs server implementations may insist on their own max_resp_sz
value, which could be smaller.
Fix this by accepting smaller max_resp_sz values from the server, as
this does not violate the protocol. The server is allowed to decrease
but not increase proposed the size, and as such values smaller than the
client-proposed ones are valid.
Fixes: 43c2e885be ("nfs4: fix channel attribute sanity-checks")
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c2f7c32b25 ]
f2fs_zero_post_eof_page() may cuase more overhead due to invalidate_lock
and page lookup, change as below to mitigate its overhead:
- check new_size before grabbing invalidate_lock
- lookup and invalidate pages only in range of [old_size, new_size]
Fixes: ba8dac350f ("f2fs: fix to zero post-eof page")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d625a2b08c ]
It reports a bug from device w/ zufs:
F2FS-fs (dm-64): Inconsistent segment (173822) type [1, 0] in SSA and SIT
F2FS-fs (dm-64): Stopped filesystem due to reason: 4
Thread A Thread B
- f2fs_expand_inode_data
- f2fs_allocate_pinning_section
- f2fs_gc_range
- do_garbage_collect w/ segno #x
- writepage
- f2fs_allocate_data_block
- new_curseg
- allocate segno #x
The root cause is: fallocate on pinning file may race w/ block allocation
as above, result in do_garbage_collect() from fallocate() may migrate
segment which is just allocated by a log, the log will update segment type
in its in-memory structure, however GC will get segment type from on-disk
SSA block, once segment type changes by log, we can detect such
inconsistency, then shutdown filesystem.
In this case, on-disk SSA shows type of segno #173822 is 1 (SUM_TYPE_NODE),
however segno #173822 was just allocated as data type segment, so in-memory
SIT shows type of segno #173822 is 0 (SUM_TYPE_DATA).
Change as below to fix this issue:
- check whether current section is empty before gc
- add sanity checks on do_garbage_collect() to avoid any race case, result
in migrating segment used by log.
- btw, it fixes misc issue in printed logs: "SSA and SIT" -> "SIT and SSA".
Fixes: 9703d69d9d ("f2fs: support file pinning for zoned devices")
Cc: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0dc7117da8 ]
Index allocation requires at least one bit in the $BITMAP attribute to
track usage of index entries. If the bitmap is empty while index blocks
are already present, this reflects on-disk corruption.
syzbot triggered this condition using a malformed NTFS image. During a
rename() operation involving a long filename (which spans multiple
index entries), the empty bitmap allowed the name to be added without
valid tracking. Subsequent deletion of the original entry failed with
-ENOENT, due to unexpected index state.
Reject such cases by verifying that the bitmap is not empty when index
blocks exist.
Reported-by: syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b0373017f711c06ada64
Fixes: d99208b919 ("fs/ntfs3: cancle set bad inode after removing name fails")
Tested-by: syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com
Signed-off-by: Moon Hee Lee <moonhee.lee.ca@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 736fc7bf5f ]
The MFT record relative to the file being opened contains its runlist,
an array containing information about the file's location on the physical
disk. Analysis of all Call Stack paths showed that the values of the
runlist array, from which LCNs are calculated, are not validated before
run_unpack function.
The run_unpack function decodes the compressed runlist data format
from MFT attributes (for example, $DATA), converting them into a runs_tree
structure, which describes the mapping of virtual clusters (VCN) to
logical clusters (LCN). The NTFS3 subsystem also has a shortcut for
deleting files from MFT records - in this case, the RUN_DEALLOCATE
command is sent to the run_unpack input, and the function logic
provides that all data transferred to the runlist about file or
directory is deleted without creating a runs_tree structure.
Substituting the runlist in the $DATA attribute of the MFT record for an
arbitrary file can lead either to access to arbitrary data on the disk
bypassing access checks to them (since the inode access check
occurs above) or to destruction of arbitrary data on the disk.
Add overflow check for addition operation.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 4342306f0f ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Vitaly Grigoryev <Vitaly.Grigoryev@kaspersky.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6fd26f5085 ]
With the change in aee03ea7ff98 ("fuse: support large folios for
writethrough writes"), this old line for setting ap->descs[0].offset is
now obsolete and unneeded. This should have been removed as part of
aee03ea7ff98.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Fixes: aee03ea7ff98 ("fuse: support large folios for writethrough writes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2e8f4c2b2b ]
mount -t f2fs -o checkpoint=disable:10% /dev/vdb /mnt/f2fs/
mount -t f2fs -o remount,checkpoint=enable /dev/vdb /mnt/f2fs/
kernel log:
F2FS-fs (vdb): Adjust unusable cap for checkpoint=disable = 204440 / 10%
If we has assigned checkpoint=enable mount option, unusable_cap{,_perc}
parameters of checkpoint=disable should be reset, then calculation and
log print could be avoid in adjust_unusable_cap_perc().
Fixes: 1ae18f71cb ("f2fs: fix checkpoint=disable:%u%%")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0b2cd50921 ]
generic/091 may fail, then it bisects to the bad commit ba8dac350f
("f2fs: fix to zero post-eof page").
What will cause generic/091 to fail is something like below Testcase #1:
1. write 16k as compressed blocks
2. truncate to 12k
3. truncate to 20k
4. verify data in range of [12k, 16k], however data is not zero as
expected
Script of Testcase #1
mkfs.f2fs -f -O extra_attr,compression /dev/vdb
mount -t f2fs -o compress_extension=* /dev/vdb /mnt/f2fs
dd if=/dev/zero of=/mnt/f2fs/file bs=12k count=1
dd if=/dev/random of=/mnt/f2fs/file bs=4k count=1 seek=3 conv=notrunc
sync
truncate -s $((12*1024)) /mnt/f2fs/file
truncate -s $((20*1024)) /mnt/f2fs/file
dd if=/mnt/f2fs/file of=/mnt/f2fs/data bs=4k count=1 skip=3
od /mnt/f2fs/data
umount /mnt/f2fs
Analisys:
in step 2), we will redirty all data pages from #0 to #3 in compressed
cluster, and zero page #3,
in step 3), f2fs_setattr() will call f2fs_zero_post_eof_page() to drop
all page cache post eof, includeing dirtied page #3,
in step 4) when we read data from page #3, it will decompressed cluster
and extra random data to page #3, finally, we hit the non-zeroed data
post eof.
However, the commit ba8dac350f ("f2fs: fix to zero post-eof page") just
let the issue be reproduced easily, w/o the commit, it can reproduce this
bug w/ below Testcase #2:
1. write 16k as compressed blocks
2. truncate to 8k
3. truncate to 12k
4. truncate to 20k
5. verify data in range of [12k, 16k], however data is not zero as
expected
Script of Testcase #2
mkfs.f2fs -f -O extra_attr,compression /dev/vdb
mount -t f2fs -o compress_extension=* /dev/vdb /mnt/f2fs
dd if=/dev/zero of=/mnt/f2fs/file bs=12k count=1
dd if=/dev/random of=/mnt/f2fs/file bs=4k count=1 seek=3 conv=notrunc
sync
truncate -s $((8*1024)) /mnt/f2fs/file
truncate -s $((12*1024)) /mnt/f2fs/file
truncate -s $((20*1024)) /mnt/f2fs/file
echo 3 > /proc/sys/vm/drop_caches
dd if=/mnt/f2fs/file of=/mnt/f2fs/data bs=4k count=1 skip=3
od /mnt/f2fs/data
umount /mnt/f2fs
Anlysis:
in step 2), we will redirty all data pages from #0 to #3 in compressed
cluster, and zero page #2 and #3,
in step 3), we will truncate page #3 in page cache,
in step 4), expand file size,
in step 5), hit random data post eof w/ the same reason in Testcase #1.
Root Cause:
In f2fs_truncate_partial_cluster(), after we truncate partial data block
on compressed cluster, all pages in cluster including the one post eof
will be dirtied, after another tuncation, dirty page post eof will be
dropped, however on-disk compressed cluster is still valid, it may
include non-zero data post eof, result in exposing previous non-zero data
post eof while reading.
Fix:
In f2fs_truncate_partial_cluster(), let change as below to fix:
- call filemap_write_and_wait_range() to flush dirty page
- call truncate_pagecache() to drop pages or zero partial page post eof
- call f2fs_do_truncate_blocks() to truncate non-compress cluster to
last valid block
Fixes: 3265d3db1f ("f2fs: support partial truncation on compressed inode")
Reported-by: Jan Prusakowski <jprusakowski@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0fe1c6bec5 ]
Should cast type of folio->index from pgoff_t to loff_t to avoid overflow
while left shift operation.
Fixes: 3265d3db1f ("f2fs: support partial truncation on compressed inode")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e75ce11790 ]
If reserve_root mount option is not assigned, __allow_reserved_blocks()
will return false, it's not correct, fix it.
Fixes: 7e65be49ed ("f2fs: add reserved blocks for root user")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 67378b7546 ]
[BUG DURING BS > PS TEST]
When running the following script on a btrfs whose block size is larger
than page size, e.g. 8K block size and 4K page size, it will trigger a
kernel BUG:
# mkfs.btrfs -s 8k $dev
# mount $dev $mnt
# mkdir $mnt/dir
# ln -s dir $mnt/link
# ls $mnt/link
The call trace looks like this:
BTRFS warning (device dm-2): support for block size 8192 with page size 4096 is experimental, some features may be missing
BTRFS info (device dm-2): checking UUID tree
BTRFS info (device dm-2): enabling ssd optimizations
BTRFS info (device dm-2): enabling free space tree
------------[ cut here ]------------
kernel BUG at /home/adam/linux/include/linux/highmem.h:275!
Oops: invalid opcode: 0000 [#1] SMP
CPU: 8 UID: 0 PID: 667 Comm: ls Tainted: G OE 6.17.0-rc4-custom+ #283 PREEMPT(full)
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:zero_user_segments.constprop.0+0xdc/0xe0 [btrfs]
Call Trace:
<TASK>
btrfs_get_extent.cold+0x85/0x101 [btrfs 7453c70c03e631c8d8bfdd4264fa62d3e238da6f]
btrfs_do_readpage+0x244/0x750 [btrfs 7453c70c03e631c8d8bfdd4264fa62d3e238da6f]
btrfs_read_folio+0x9c/0x100 [btrfs 7453c70c03e631c8d8bfdd4264fa62d3e238da6f]
filemap_read_folio+0x37/0xe0
do_read_cache_folio+0x94/0x3e0
__page_get_link.isra.0+0x20/0x90
page_get_link+0x16/0x40
step_into+0x69b/0x830
path_lookupat+0xa7/0x170
filename_lookup+0xf7/0x200
? set_ptes.isra.0+0x36/0x70
vfs_statx+0x7a/0x160
do_statx+0x63/0xa0
__x64_sys_statx+0x90/0xe0
do_syscall_64+0x82/0xae0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
Please note bs > ps support is still under development and the
enablement patch is not even in btrfs development branch.
[CAUSE]
Btrfs reuses its data folio read path to handle symbolic links, as the
symbolic link target is stored as an inline data extent.
But for newly created inodes, btrfs only set the minimal order if the
target inode is a regular file.
Thus for above newly created symbolic link, it doesn't properly respect
the minimal folio order, and triggered the above crash.
[FIX]
Call btrfs_set_inode_mapping_order() unconditionally inside
btrfs_create_new_inode().
For symbolic links this will fix the crash as now the folio will meet
the minimal order.
For regular files this brings no change.
For directory/bdev/char and all the other types of inodes, they won't
go through the data read path, thus no effect either.
Fixes: cc38d178ff ("btrfs: enable large data folio support under CONFIG_BTRFS_EXPERIMENTAL")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2d83ed6c6c ]
Since the support of bs < ps support, extent_writepage_io() will submit
multiple blocks inside the folio.
But if we hit error submitting one sector, but the next sector can still
be submitted successfully, the function extent_writepage_io() will still
return 0.
This will make btrfs to silently ignore the error without setting error
flag for the filemap.
Fix it by recording the first error hit, and always return that value.
Fixes: 8bf334beb3 ("btrfs: fix double accounting race when extent_writepage_io() failed")
Reviewed-by: Daniel Vacek <neelx@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fad988a215 ]
Already do real negotiation in smb_direct_handle_connect_request()
where we see the requested initiator_depth and responder_resources
from the client.
We should detect legacy iwarp clients using MPA v1
with the custom IRD/ORD negotiation.
We need to send the custom IRD/ORD in big endian,
but we need to try to let clients with broken requests
using little endian (older cifs.ko) to work.
Note the reason why this uses u8 for
initiator_depth and responder_resources is
that the rdma layer also uses it.
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: linux-rdma@vger.kernel.org
Fixes: 0626e6641f ("cifsd: add server handler for central processing and tranport layers")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ef71f1e046 ]
Do a real negotiation and check the servers initiator_depth and
responder_resources.
This should use big endian in order to be useful.
I have captures of windows clients showing this.
The fact that we used little endian up to now
means that we sent very large numbers and the
negotiation with the server truncated them to the
server limits.
Note the reason why this uses u8 for
initiator_depth and responder_resources is
that the rdma layer also uses it.
The inconsitency regarding the initiator_depth
and responder_resources values being reversed
for iwarp devices in RDMA_CM_EVENT_ESTABLISHED
should also be fixed later, but for now we should
fix it.
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: linux-rdma@vger.kernel.org
Fixes: c739858334 ("CIFS: SMBD: Implement RDMA memory registration")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 334c0e493c ]
Since all real encoded extents (directly handled by the decompression
subsystem) have a sane, limited maximum decoded length
(Z_EROFS_PCLUSTER_MAX_DSIZE), and the read-more policy is only applied
if needed.
However, it makes no sense to read more for non-encoded maps, such as
fragment extents, since such extents can be huge (up to i_size) and
there is no benefit to reading more at this layer.
For normal images, it does not really matter, but for crafted images
generated by syzbot, excessively large fragment extents can cause
read-more to run for an overly long time.
Reported-and-tested-by: syzbot+1a9af3ef3c84c5e14dcc@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/68c8583d.050a0220.2ff435.03a3.GAE@google.com
Fixes: b44686c839 ("erofs: fix large fragment handling")
Fixes: b15b2e307c ("erofs: support on-disk compressed fragments data")
Reviewed-by: Hongbo Li <lihongbo22@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6ab26555c9 ]
GFS2 has been calling functions like dlm_lock() even after the lockspace
that these functions operate on has been released with
dlm_release_lockspace(). It has always assumed that those functions
would return -EINVAL in that case, but that was never guaranteed, and it
certainly is no longer the case since commit 4db41bf4f0 ("dlm: remove
ls_local_handle from struct dlm_ls").
To fix that, add proper lockspace locking.
Fixes: 3e11e53041 ("GFS2: ignore unlock failures after withdraw")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2309a01351 ]
Check for asynchronous completion and clear the GLF_PENDING_REPLY flag
earlier in do_xmote(). This will make future changes more readable.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Stable-dep-of: 6ab26555c9 ("gfs2: Add proper lockspace locking")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bddb53b776 ]
Get rid of the GLF_INVALIDATE_IN_PROGRESS flag: it was originally used
to indicate to add_to_queue() that the ->go_sync() and ->go_invalid()
operations were in progress, but as we have established in commit "gfs2:
Fix LM_FLAG_TRY* logic in add_to_queue", add_to_queue() has no need to
know.
Commit d99724c3c3 describes a race in which GLF_INVALIDATE_IN_PROGRESS
is used to serialize two processes which are both in do_xmote() at the
same time. That analysis is wrong: the serialization happens via the
GLF_LOCK flag, which ensures that at most one glock operation can be
active at any time.
Fixes: d99724c3c3 ("gfs2: Close timing window with GLF_INVALIDATE_IN_PROGRESS")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9b54770b68 ]
In do_xmote(), remove the duplicate check for the ->go_sync and
->go_inval glock operations. They are either both defined, or none of
them are.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Stable-dep-of: bddb53b776 ("gfs2: Get rid of GLF_INVALIDATE_IN_PROGRESS")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0c23e24164 ]
The logic in add_to_queue() for determining whether a LM_FLAG_TRY or
LM_FLAG_TRY_1CB holder should be queued does not make any sense: we are
interested in wether or not the new operation will block behind an
existing or future holder in the queue, but the current code checks for
ongoing locking or ->go_inval() operations, which has little to do with
that.
Replace that code with something more sensible, remove the incorrect
add_to_queue() function annotations, remove the similarly misguided
do_error(gl, 0) call in do_xmote(), and add a missing comment to the
same call in do_promote().
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Stable-dep-of: bddb53b776 ("gfs2: Get rid of GLF_INVALIDATE_IN_PROGRESS")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fd70ab7155 ]
The gl_req field and GLF_BLOCKING flag are only relevant to gdlm_lock(),
its callback gdlm_ast(), and their helpers, so set and clear them inside
lock_dlm.c.
Also, the LM_FLAG_ANY flag is relevant to gdlm_lock(), but do_xmote()
doesn't pass that flag down to gdlm_lock() as it should. Fix that by
passing down all the flags.
In addition, document the effect of the LM_FLAG_ANY flag on locks held
in EX mode locally.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Stable-dep-of: bddb53b776 ("gfs2: Get rid of GLF_INVALIDATE_IN_PROGRESS")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aa94ad9ab2 ]
There is an extraneous space before a newline in a fs_err message.
Remove it
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Stable-dep-of: bddb53b776 ("gfs2: Get rid of GLF_INVALIDATE_IN_PROGRESS")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 061df28b82 ]
Commit 865cc3e9cc ("gfs2: fix a deadlock on withdraw-during-mount")
added a statement to do_xmote() to clear the GLF_INVALIDATE_IN_PROGRESS
flag a second time after it has already been cleared. Fix that.
Fixes: 865cc3e9cc ("gfs2: fix a deadlock on withdraw-during-mount")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit c18ecd99e0 upstream.
As syzbot reported below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/file.c:1243!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5354 Comm: syz.0.0 Not tainted 6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT(full)
RIP: 0010:f2fs_truncate_hole+0x69e/0x6c0 fs/f2fs/file.c:1243
Call Trace:
<TASK>
f2fs_punch_hole+0x2db/0x330 fs/f2fs/file.c:1306
f2fs_fallocate+0x546/0x990 fs/f2fs/file.c:2018
vfs_fallocate+0x666/0x7e0 fs/open.c:342
ksys_fallocate fs/open.c:366 [inline]
__do_sys_fallocate fs/open.c:371 [inline]
__se_sys_fallocate fs/open.c:369 [inline]
__x64_sys_fallocate+0xc0/0x110 fs/open.c:369
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e65f8ebe9
w/ a fuzzed image, f2fs may encounter panic due to it detects inconsistent
truncation range in direct node in f2fs_truncate_hole().
The root cause is: a non-inode dnode may has the same footer.ino and
footer.nid, so the dnode will be parsed as an inode, then ADDRS_PER_PAGE()
may return wrong blkaddr count which may be 923 typically, by chance,
dn.ofs_in_node is equal to 923, then count can be calculated to 0 in below
statement, later it will trigger panic w/ f2fs_bug_on(, count == 0 || ...).
count = min(end_offset - dn.ofs_in_node, pg_end - pg_start);
This patch introduces a new node_type NODE_TYPE_NON_INODE, then allowing
passing the new_type to sanity_check_node_footer in f2fs_get_node_folio()
to detect corruption that a non-inode dnode has the same footer.ino and
footer.nid.
Scripts to reproduce:
mkfs.f2fs -f /dev/vdb
mount /dev/vdb /mnt/f2fs
touch /mnt/f2fs/foo
touch /mnt/f2fs/bar
dd if=/dev/zero of=/mnt/f2fs/foo bs=1M count=8
umount /mnt/f2fs
inject.f2fs --node --mb i_nid --nid 4 --idx 0 --val 5 /dev/vdb
mount /dev/vdb /mnt/f2fs
xfs_io /mnt/f2fs/foo -c "fpunch 6984k 4k"
Cc: stable@kernel.org
Reported-by: syzbot+b9c7ffd609c3f09416ab@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/68a68e27.050a0220.1a3988.0002.GAE@google.com
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
aren't considered necessary for -stable kernels. 6 of these fixes are for
MM.
All singletons, please see the changelogs for details.
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Merge tag 'mm-hotfixes-stable-2025-09-27-22-35' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"7 hotfixes. 4 are cc:stable and the remainder address post-6.16 issues
or aren't considered necessary for -stable kernels. 6 of these fixes
are for MM.
All singletons, please see the changelogs for details"
* tag 'mm-hotfixes-stable-2025-09-27-22-35' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
include/linux/pgtable.h: convert arch_enter_lazy_mmu_mode() and friends to static inlines
mm/damon/sysfs: do not ignore callback's return value in damon_sysfs_damon_call()
mailmap: add entry for Bence Csókás
fs/proc/task_mmu: check p->vec_buf for NULL
kmsan: fix out-of-bounds access to shadow memory
mm/hugetlb: fix copy_hugetlb_page_range() to use ->pt_share_count
mm/hugetlb: fix folio is still mapped when deleted
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Merge tag 'v6.17rc7-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:
- Fix unlink bug
- Fix potential out of bounds access in processing compound requests
* tag 'v6.17rc7-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: fix wrong index reference in smb2_compound_op()
smb: client: handle unlink(2) of files open by different clients
In smb2_compound_op(), the loop that processes each command's response
uses wrong indices when accessing response bufferes.
This incorrect indexing leads to improper handling of command results.
Also, if incorrectly computed index is greather than or equal to
MAX_COMPOUND, it can cause out-of-bounds accesses.
Fixes: 3681c74d34 ("smb: client: handle lack of EA support in smb2_query_path_info()") # 6.14
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Commit 20d72b00ca ("netfs: Fix the request's work item to not
require a ref") modified netfs_alloc_request() to initialize the
reference counter to 2 instead of 1. The rationale was that the
requet's "work" would release the second reference after completion
(via netfs_{read,write}_collection_worker()). That works most of the
time if all goes well.
However, it leaks this additional reference if the request is released
before the I/O operation has been submitted: the error code path only
decrements the reference counter once and the work item will never be
queued because there will never be a completion.
This has caused outages of our whole server cluster today because
tasks were blocked in netfs_wait_for_outstanding_io(), leading to
deadlocks in Ceph (another bug that I will address soon in another
patch). This was caused by a netfs_pgpriv2_begin_copy_to_cache() call
which failed in fscache_begin_write_operation(). The leaked
netfs_io_request was never completed, leaving `netfs_inode.io_count`
with a positive value forever.
All of this is super-fragile code. Finding out which code paths will
lead to an eventual completion and which do not is hard to see:
- Some functions like netfs_create_write_req() allocate a request, but
will never submit any I/O.
- netfs_unbuffered_read_iter_locked() calls netfs_unbuffered_read()
and then netfs_put_request(); however, netfs_unbuffered_read() can
also fail early before submitting the I/O request, therefore another
netfs_put_request() call must be added there.
A rule of thumb is that functions that return a `netfs_io_request` do
not submit I/O, and all of their callers must be checked.
For my taste, the whole netfs code needs an overhaul to make reference
counting easier to understand and less fragile & obscure. But to fix
this bug here and now and produce a patch that is adequate for a
stable backport, I tried a minimal approach that quickly frees the
request object upon early failure.
I decided against adding a second netfs_put_request() each time
because that would cause code duplication which obscures the code
further. Instead, I added the function netfs_put_failed_request()
which frees such a failed request synchronously under the assumption
that the reference count is exactly 2 (as initially set by
netfs_alloc_request() and never touched), verified by a
WARN_ON_ONCE(). It then deinitializes the request object (without
going through the "cleanup_work" indirection) and frees the allocation
(with RCU protection to protect against concurrent access by
netfs_requests_seq_start()).
All code paths that fail early have been changed to call
netfs_put_failed_request() instead of netfs_put_request().
Additionally, I have added a netfs_put_request() call to
netfs_unbuffered_read() as explained above because the
netfs_put_failed_request() approach does not work there.
Fixes: 20d72b00ca ("netfs: Fix the request's work item to not require a ref")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paulo Alcantara <pc@manguebit.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: stable@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
When the PAGEMAP_SCAN ioctl is invoked with vec_len = 0 reaches
pagemap_scan_backout_range(), kernel panics with null-ptr-deref:
[ 44.936808] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 44.937797] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[ 44.938391] CPU: 1 UID: 0 PID: 2480 Comm: reproducer Not tainted 6.17.0-rc6 #22 PREEMPT(none)
[ 44.939062] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 44.939935] RIP: 0010:pagemap_scan_thp_entry.isra.0+0x741/0xa80
<snip registers, unreliable trace>
[ 44.946828] Call Trace:
[ 44.947030] <TASK>
[ 44.949219] pagemap_scan_pmd_entry+0xec/0xfa0
[ 44.952593] walk_pmd_range.isra.0+0x302/0x910
[ 44.954069] walk_pud_range.isra.0+0x419/0x790
[ 44.954427] walk_p4d_range+0x41e/0x620
[ 44.954743] walk_pgd_range+0x31e/0x630
[ 44.955057] __walk_page_range+0x160/0x670
[ 44.956883] walk_page_range_mm+0x408/0x980
[ 44.958677] walk_page_range+0x66/0x90
[ 44.958984] do_pagemap_scan+0x28d/0x9c0
[ 44.961833] do_pagemap_cmd+0x59/0x80
[ 44.962484] __x64_sys_ioctl+0x18d/0x210
[ 44.962804] do_syscall_64+0x5b/0x290
[ 44.963111] entry_SYSCALL_64_after_hwframe+0x76/0x7e
vec_len = 0 in pagemap_scan_init_bounce_buffer() means no buffers are
allocated and p->vec_buf remains set to NULL.
This breaks an assumption made later in pagemap_scan_backout_range(), that
page_region is always allocated for p->vec_buf_index.
Fix it by explicitly checking p->vec_buf for NULL before dereferencing.
Other sites that might run into same deref-issue are already (directly or
transitively) protected by checking p->vec_buf.
Note:
From PAGEMAP_SCAN man page, it seems vec_len = 0 is valid when no output
is requested and it's only the side effects caller is interested in,
hence it passes check in pagemap_scan_get_args().
This issue was found by syzkaller.
Link: https://lkml.kernel.org/r/20250922082206.6889-1-acsjakub@amazon.de
Fixes: 52526ca7fd ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs")
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jinjiang Tu <tujinjiang@huawei.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Penglei Jiang <superman.xpt@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
