This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
ksmbd_tree_conn_connect() publishes a new tree connection in
sess->tree_conns with a single reference and returns its pointer to
smb2_tree_connect(). The handler continues to initialize the object and
build the response after publication. A concurrent session logoff can
erase the connection and drop that reference, freeing the object while
the handler still uses it.
BUG: KASAN: slab-use-after-free in smb2_tree_connect+0xe3d/0xf90
smb2_tree_connect (fs/smb/server/smb2pdu.c:2872)
handle_ksmbd_work
process_one_work
worker_thread
kthread
After xa_store() succeeds, take a second reference before releasing
tree_conns_lock. The original reference belongs to the xarray entry and
the second belongs to the creating smb2_tree_connect() handler.
Keep the references balanced in every path:
- On normal exit or an error after publication, smb2_tree_connect()
drops its creator reference. Error cleanup also calls
ksmbd_tree_conn_disconnect(), which drops the xarray reference only if
it removes the exact entry.
- SMB2 TREE_DISCONNECT uses the same helper to remove the entry and drop
its xarray reference. The request's existing lookup reference remains
owned by the request and is released by the existing cleanup.
- Session LOGOFF removes each entry and drops its xarray reference. If
it wins the race, later cleanup sees that the entry is gone and does
not drop that reference again.
To enforce this ownership, claim the disconnected state and erase the
exact entry atomically under tree_conns_lock. This guarantees one drop
for the xarray reference and one drop by each in-flight user, regardless
of which teardown path wins. If logoff removes the entry before
initialization completes, fail the connect instead of marking the
detached object TREE_CONNECTED.
Fixes: 33b235a6e6 ("ksmbd: fix race condition between tree conn lookup and disconnect")
Reported-by: Xiang Mei (Microsoft) <xmei5@asu.edu>
Cc: AutonomousCodeSecurity@microsoft.com
Cc: stable@vger.kernel.org
Signed-off-by: Cen Zhang (Microsoft Security FORGE Labs) <cenzhang@linux.microsoft.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
ksmbd_vfs_copy_file_ranges() rejects negative source offsets in the
copy loop, but it does not validate target offsets. It also calculates
lock and overlap endpoints before ensuring that either range fits within
MAX_LFS_FILESIZE.
When the target is an alternate data stream, the buffered path passes a
negative target offset to ksmbd_vfs_stream_write(). Let n be Length and
let -d be TargetOffset, where 0 < d < n <= XATTR_SIZE_MAX. For an empty
stream, the writer allocates n - d bytes, then copies n bytes starting d
bytes before the allocation. An authenticated SMB client can control d
and the source data, overwrite kernel heap memory, and crash the host.
Validate both ranges before lock, overlap, or I/O calculations.
Fixes: 8482150a07 ("ksmbd: support copychunk for alternate data streams")
Assisted-by: Antiproof:GPT-5.6-Sol
Signed-off-by: Alon Shakevsky <shakevsky@berkeley.edu>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
smb2_oplock_break_noti() reads opinfo->conn without any lock and
dereferences it after two allocations which may sleep. When the
durable handle owning the oplock is disconnected, session_fd_check()
clears opinfo->conn and drops its conn reference under ci->m_lock, and
the last ksmbd_conn_put() frees the connection. A break triggered by
another connection that races with the teardown can then resurrect the
freed connection: ksmbd_conn_get() is a plain atomic_inc, and the
queued break work later dereferences the stale conn via
ksmbd_conn_write(), a use-after-free reachable by any authenticated
client holding a durable batch oplock.
Thread the caller's inode into the notification path instead of taking
a new reference on it. Every caller of oplock_break() already holds a
live ksmbd_file (or an explicit ksmbd_inode_lookup_lock() reference,
in the parent lease break paths) on the inode that owns the break
target's oplock list, so ci cannot be freed during the call, and its
lock can be taken without dereferencing opinfo->o_fp, which a
concurrent close may free. Select and pin the connection under
ci->m_lock, the same lock session_fd_check() and
ksmbd_reopen_durable_fd() use to update opinfo->conn, so a concurrent
detach either loses the race to the clear or keeps the connection
alive until the notification work releases it. Transfer the reference
to the work item and release it on allocation failures.
Fixes: b003086d76 ("ksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers")
Cc: stable@vger.kernel.org
Signed-off-by: Abdifatah Suruur <suruurism@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Use an unsigned int for the work state so xchg() uses a supported
4-byte operation on sparc.
Fixes: d12168084c ("ksmbd: safely drain sessions during logoff")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202609021157.8f7Wx34I-lkp@intel.com/
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
A batch of bug fixes for the SMB client:
- Fixes for fallocate range operations (insert, collapse, zero, punch
hole): the insert range implementation copied overlapping chunks in
the wrong direction, corrupting file data on every server except
Windows. Several related issues in the same area are also
addressed — stale page cache and FS-Cache readback, an integer
truncation on large files, missing RLIMIT_FSIZE validation and
missing sparse file marking.
- Data corruption fixes in the O_TRUNC open path: one where i_size
was zeroed before the server confirmed the truncate and another
where the lack of locking allowed concurrent buffered writes to be
silently discarded.
- Heap overflow fixes in legacy SMB1 paths: one in extended attribute
writes and one in POSIX ACL handling, both exploitable via
unprivileged setxattr(2).
- Fix for multiuser mount with krb5 failing because the username
option was not propagated to new per-user connections.
- Fix for split debug message in __release_mid() after a printk
conversion.
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Merge tag 'cifs-fixes-7.3-rc2' of https://git.manguebit.org/linux
Pull smb client fixes from Paulo Alcantara:
- Fixes for fallocate range operations (insert, collapse, zero, punch
hole)
The insert range implementation copied overlapping chunks in the
wrong direction, corrupting file data on every server except Windows.
Several related issues in the same area are also addressed — stale
page cache and FS-Cache readback, an integer truncation on large
files, missing RLIMIT_FSIZE validation and missing sparse file
marking.
- Data corruption fixes in the O_TRUNC open path: one where i_size was
zeroed before the server confirmed the truncate and another where the
lack of locking allowed concurrent buffered writes to be silently
discarded
- Heap overflow fixes in legacy SMB1 paths: one in extended attribute
writes and one in POSIX ACL handling, both exploitable via
unprivileged setxattr(2)
- Fix for multiuser mount with krb5 failing because the username option
was not propagated to new per-user connections
- Fix for split debug message in __release_mid() after a printk
conversion
* tag 'cifs-fixes-7.3-rc2' of https://git.manguebit.org/linux:
smb: client: reject SetEA requests that do not fit the request buffer
smb: client: fix data corruption with concurrent writes and O_TRUNC
cifs: don't update i_size in cifs_do_truncate without a cached handle
smb: client: fix heap overflow in cifs_do_set_acl()
smb: client: fix multiuser mount with krb5
smb: client: transport: Fix debug printing in __release_mid()
smb/client: invalidate fscache for fallocate range operations
smb/client: fix stale page cache in insert/collapse range
smb/client: fix integer truncation in collapse range
smb/client: fix data corruption in emulated insert range
smb/client: mark file sparse before emulating insert range
smb/client: validate new EOF for zero range
smb/client: validate new EOF for insert range
cifs: add revalidation on FSCTL failure in smb2_duplicate_extents()
the response buffer.
- Initialize missing fields in FS_OBJECT_ID_INFORMATION,
FS_CONTROL_INFORMATION, and FS_POSIX_INFORMATION.
- Propagate DACL parsing and allocation failures so malformed security
descriptors are rejected.
- Rate-limit errors for unmapped SIDs to prevent kernel log flooding.
- Drain multichannel sessions during LOGOFF, wake deferred locks and
cancellable requests, and ensure cancellation callbacks run only once.
- Fix listener kthread reference handling and teardown ordering during
netdevice events.
- Validate normalized-name and IPC share configuration response lengths.
- Update the KSMBD MAINTAINERS entry and add Paulo Alcantara as
an SMBDIRECT co-maintainer.
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Merge tag 'ksmbd-for-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/smb
Pull smb server fixes from Namjae Jeon:
- Prevent unintended data exposure by clearing pipe compound padding
and the response buffer
- Initialize missing fields in FS_OBJECT_ID_INFORMATION,
FS_CONTROL_INFORMATION, and FS_POSIX_INFORMATION
- Propagate DACL parsing and allocation failures so malformed security
descriptors are rejected
- Rate-limit errors for unmapped SIDs to prevent kernel log flooding
- Drain multichannel sessions during LOGOFF, wake deferred locks and
cancellable requests, and ensure cancellation callbacks run only once
- Fix listener kthread reference handling and teardown ordering during
netdevice events
- Validate normalized-name and IPC share configuration response lengths
- Update the KSMBD MAINTAINERS entry and add Paulo Alcantara as an
SMBDIRECT co-maintainer
* tag 'ksmbd-for-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/smb:
ksmbd: validate normalized name response length
ksmbd: fix listener task lifetime on netdev events
ksmbd: prevent out-of-bounds reads in share config responses
ksmbd: rate limit unmapped SID errors
ksmbd: propagate DACL parsing errors
ksmbd: zero pipe read compound padding
ksmbd: safely drain sessions during logoff
MAINTAINERS: Update the KSMBD entry
MAINTAINERS: Add Paulo Alcantara as an SMBDIRECT co-maintainer
ksmbd: fill in FileSysIdentifier in FS_POSIX_INFORMATION
ksmbd: initialize FileSystemControlFlags in FS_CONTROL_INFORMATION
ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in
CIFSSMBSetEA() copies the caller's extended attribute value into the
SMB request buffer without checking that it fits. The requirement is
stated in the source but was never implemented:
/*BB add length check to see if it would fit in
negotiated SMB buffer size BB */
/* if (ea_value_len > buffer_size - 512 (enough for header)) */
if (ea_value_len)
memcpy(parm_data->list.name + name_len + 1,
ea_value, ea_value_len);
The only bound applied on the way in is in cifs_xattr_set():
#define MAX_EA_VALUE_SIZE CIFSMaxBufSize
...
if (size > MAX_EA_VALUE_SIZE)
CIFSMaxBufSize is the full payload capacity of the buffer, so a value
of exactly that size leaves no room for the SMB header, the TRANS2
parameter block, the fealist header and the EA name that are written
ahead of it in the same object.
SendReceive() already enforces the correct limit on this very length:
if (in_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE)
but it is called after the copy has taken place. An unprivileged
setxattr(2) on an SMB1 mount with a 250-byte name and a 16384-byte
value writes 16384 bytes starting 345 bytes into a 16588-byte
cifs_request object, ending 141 bytes past it:
BUG: KASAN: slab-out-of-bounds in CIFSSMBSetEA+0xabc/0xde0
Write of size 16384 at addr ffff888003aa0159 by task init/68
__asan_memcpy+0x3c/0x60
CIFSSMBSetEA+0xabc/0xde0
cifs_xattr_set+0xd3a/0xff0
__vfs_setxattr+0x13e/0x1a0
The buggy address is located 345 bytes inside of
allocated 16588-byte region
Apply SendReceive()'s limit to the assembled request before the copy
rather than after it, and widen the byte counters so the sum cannot
wrap before it is tested.
byte_count is also tested against U16_MAX, because it is stored in the
16-bit pSMB->ByteCount. That becomes reachable when CIFSMaxBufSize is
raised at module load, where it may be set as high as 1024*127: with a
5-byte EA name and a 65521-byte value, count is exactly U16_MAX while
byte_count is 65556, and cpu_to_le16() would truncate it to 20 and
transmit a frame whose ByteCount does not match its length. Testing
byte_count covers count as well, since byte_count is the larger of the
two and count's only 16-bit consumer is written after this point.
check_add_overflow() is evaluated first so that total_len is assigned
before it is reported.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Yunpeng Tian <shionthanatos@gmail.com>
Reported-by: Mingda Zhang <npczmd@qq.com>
Reported-by: Gongming Wang <gmwgg05@gmail.com>
Reported-by: Qinrun Dai <jupmouse@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Yunpeng Tian <shionthanatos@gmail.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
cifs_do_truncate() flushes dirty pages with filemap_write_and_wait()
and truncates the file on the server, but in the old code both
operations ran without holding i_rwsem or invalidate_lock. A
concurrent buffered write via netfs_perform_write() -- which only
needs i_rwsem shared -- could dirty new pages after the flush but
before the local truncation, and those pages would be silently
discarded by cifs_setsize() -> truncate_pagecache().
Fix by acquiring inode_lock (exclusive i_rwsem) and
filemap_invalidate_lock at the top of cifs_do_truncate(), so the
entire flush-truncate-resize sequence is atomic with respect to:
- buffered writes (blocked by exclusive i_rwsem, since
netfs_start_io_write takes i_rwsem shared),
- read page faults (blocked by exclusive invalidate_lock, since
filemap_fault takes it shared),
- writeback collection (blocked by netfs_wb_begin/netfs_wb_end
around the server truncate and local resize, since
netfs_writepages also acquires the wb lock).
Fixes: 110fee6b9b ("smb: client: fix missing timestamp updates with O_TRUNC")
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: stable@vger.kernel.org
FILE_NORMALIZED_NAME_INFORMATION converts the open file path to UTF-16.
smb2_allocate_rsp_buf() leaves these responses in the 448-byte small
buffer, and get_file_normalized_name_info() converts the path without
checking the remaining space.
An authenticated client can query a long path and make
smbConvertToUTF16() write beyond work->response_buf.
Use the large response buffer for normalized-name queries. Before
conversion, verify that the response has room for the worst-case UTF-16
output and its terminator.
Fixes: 10aeff72ab ("ksmbd: support normalized name information")
Assisted-by: Antiproof:GPT-5.6-Sol
Signed-off-by: Alon Shakevsky <shakevsky@berkeley.edu>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
The listener thread exits when its listening socket is shutdown. The
netdevice notifier shuts down the socket before calling kthread_stop(), so
the task_struct can be freed before kthread_stop() gets its reference.
Create the listener in a stopped state and hold an extra task_struct
reference until kthread_stop_put() completes. Also stop and release
listeners before freeing their interface records during TCP teardown.
Fixes: 3316a8fc84 ("ksmbd: server: avoid busy polling in accept loop")
Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
A client can include many structurally valid but unmapped SIDs in a DACL.
Logging every mapping failure lets one request generate hundreds of kernel
error messages.
Rate limit the message to prevent an authenticated client from flooding
the kernel log.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Reported-by: Cheryl Babcock <cheryl@renat.io>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
parse_dacl() silently accepts truncated ACEs and allocation failures,
allowing set_info_sec() to continue with an incomplete ACL conversion.
Return parsing and allocation errors to parse_sec_desc() so malformed
security descriptors are rejected before inode attributes or ACL xattrs
are updated.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Reported-by: Cheryl Babcock <cheryl@renat.io>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Compound response handling extends the last response iov to an eight-byte
boundary.
smb2_read_pipe() allocates only the payload size, so the alignment padding
can expose up to seven bytes of uninitialized kernel heap memory.
Allocate the aligned size and clear the unused tail before pinning the
response buffer.
Fixes: e2b76ab8b5 ("ksmbd: add support for read compound")
Reported-by: Cheryl Babcock <cheryl@renat.io>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
SMB3 multichannel allows requests for one session to run on multiple
connections. Wait for all channels bound to a session before freeing
shared session objects.
A deferred byte-range lock remains counted as a running request and only
wakes when its file closes. Wake blocked locks during the drain without
unpublishing or modifying their file objects. Synchronous CANCEL requests
must invoke their cancellation callback to wake pending operations, while
CHANGE_NOTIFY completion remains specific to the asynchronous path.
Serialize session teardown with channel registration and previous-session
cleanup, and use atomic work-state transitions so LOGOFF, CANCEL, and
connection teardown invoke cancellation callbacks only once.
Fixes: 76e98a158b ("ksmbd: fix race condition between destroy_previous_session() and smb2 operations()")
Reported-by: Cheryl Babcock <cheryl@renat.io>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
smb2_get_info_filesystem() reports 56 bytes for FS_POSIX_INFORMATION,
that is the whole of FILE_SYSTEM_POSIX_INFO, but never assigns
FileSysIdentifier. Those eight bytes go to the client as they are found
in the response buffer.
The buffer is zeroed on allocation, so a standalone request leaks
nothing. A compound request can leak: the offset of the next response
is advanced by the length pinned for the previous one, so a reply that
was written into the buffer and then dropped in favour of the short
error response of smb2_set_err_rsp() stays there, and the next reply is
laid over it with only the header cleared.
Report the file system id statfs() returned, which is what the field is
for. FileSysIdentifier is __le64 and f_fsid is a pair of ints, so
assemble the value first, val[0] as the low half, and convert it on the
way out.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Signed-off-by: Aleksandr Khromov <haa@amicon.ru>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
smb2_get_info_filesystem() reports 48 bytes for FS_CONTROL_INFORMATION,
that is the whole of struct smb2_fs_control_info, but never assigns
FileSystemControlFlags. Those four bytes go to the client as they are
found in the response buffer.
The buffer is zeroed on allocation, so a standalone request leaks
nothing. A compound request can leak: the offset of the next response
is advanced by the length pinned for the previous one, so a reply that
was written into the buffer and then dropped in favour of the short
error response of smb2_set_err_rsp() stays there, and the next reply is
laid over it with only the header cleared.
ksmbd does not implement quota tracking, so report no control flags.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Signed-off-by: Aleksandr Khromov <haa@amicon.ru>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
smb2_get_info_filesystem() reports 64 bytes for FS_OBJECT_ID_INFORMATION,
that is the whole of struct object_id_info, but writes only 46 of them:
- objid[] is 16 bytes, and when the volume UUID is not available only
sizeof(stfs.f_fsid) (8) bytes are copied into it;
- extended_info.version_string[] is STRING_LENGTH (28) bytes, and only
strlen("1.1.0") (5) bytes are copied into it.
The response buffer is zeroed on allocation (kvzalloc() in
smb2_allocate_rsp_buf()), so for a standalone request the remaining 31
bytes are zero. In a compound request they need not be. The offset of
the next response is advanced by the length pinned for the previous one,
so if a preceding command wrote its reply into the buffer and then
failed, smb2_set_err_rsp() pins only the short error response and the
next reply lands inside the area that has already been written. Only
the header is cleared there:
memset((char *)rsp_hdr, 0, sizeof(struct smb2_hdr) + 2);
The client then receives up to 31 bytes of a response it was not meant
to see, including one that failed with an access denied error.
Clear the structure before filling it in. As a side effect
version_string is now NUL terminated.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Suggested-by: ChenXiaoSong <chenxiaosong@chenxiaosong.com>
Cc: stable@vger.kernel.org
Signed-off-by: Aleksandr Khromov <haa@amicon.ru>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
If find_writable_file() returns null, cifs_file_flush will return
0 without issuing set_file_size, and the outer 'if (!rc)' block
will set i_size to 0 before telling the server to truncate. If
the cifs_open() then fails, the inode will have size 0, while
the server file is unchanged.
Move the netfs_resize_file() and cifs_setsize() into the 'if
(cfile)', so they only run after a successful set_file_size.
In the no-handle else branch, evict stale pages with
truncate_inode_pages before the O_TRUNC open to dispose of old
cache pages, and let the open response set the i_size.
Fixes: 110fee6b9b ("smb: client: fix missing timestamp updates with O_TRUNC")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
cifs_set_acl() validates ACL size using posix_acl_xattr_size():
4 + (count * 8) // 4-byte header + 8 bytes per ACE
cifs_do_set_acl() then calls posix_acl_to_cifs() to write the CIFS
wire format into the same buffer:
6 + (count * 10) // 6-byte header + 10 bytes per ACE
An ACL that passes the xattr-based check in cifs_set_acl() can
overflow the heap when posix_acl_to_cifs() writes the larger CIFS
format.
Validate the CIFS format size against the remaining buffer space and
USHRT_MAX before converting--data_count is __u16, so sizes above
USHRT_MAX truncate the on-wire packet length, causing the server to
apply a partial ACL. Replace MaxDataCount = 1000 with
min(CIFSMaxBufSize, USHRT_MAX).
Fixes: dc1af4c4b4 ("cifs: implement set acl method")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Customer reported that they could no longer mount their SMB shares
with multiuser mount option and krb5. Turned out that the client
wasn't duplicating username option when creating multiuser
connections, therefore failing to retrieve credentials as
cifs.upcall(8) couldn't find them in keytab.
Fix this by duplicating username option (if set) from original fs
context before creating multiuser connections with krb5.
Reproducer:
```
$ ktutil
ktutil: add_entry -password -p testuser -k 1 -e aes256-cts
Password for testuser@ZELDA.TEST:
ktutil: write_kt /etc/krb5.keytab
ktutil: quit
$ klist -ke
Keytab name: FILE:/etc/krb5.keytab
KVNO Principal
---- ----------------------------------------------------------------
1 testuser@ZELDA.TEST (aes256-cts-hmac-sha1-96)
$ mount.cifs //w22-root2/scratch /mnt/1 -o \
uid=1000,sec=krb5,username=testuser@ZELDA.TEST,multiuser
mount error(13): Permission denied
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs) and
kernel log messages (dmesg)
```
Reported-by: Jacob Shivers <jshivers@redhat.com>
Fixes: 12b4c5d98c ("smb: client: fix krb5 mount with username option")
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Long time ago during upgrading printk():s to the respective pr_<level>()
calls one misconversion happened and nobody has noticed that. So,
previously printk(KERN_DEBUG) + printk() worked as one long debug print
since the trailing '\n' is only present in the followup printk() format
string. The culprit change missed that and split the message to two on
the different levels. Restore the original behaviour to make users be
less confused in the most likely never happen cases of partially getting
that message.
Fixes: 0b456f04bc ("cifs: convert printk(LEVEL...) to pr_<level>")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
smb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and
smb3_collapse_range() modify file contents through server-side range
operations. These operations discard the affected page cache, but leave
the FS-Cache cookie valid, so a later read may return data cached before
the range operation.
Fix this by invalidating FS-Cache after outstanding I/O has completed
and before modifying the file on the server.
Run the following as root on a CIFS mount with fsc enabled and an active
CacheFiles backend:
bash -c '
MNT=/mnt/cifs
FILE="$MNT/repro"
# Generate four 1 MiB random blocks: [A][B][C][D].
dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none
# Expected contents after zeroing B: [A][zero][C][D].
cp /tmp/src /tmp/expected
dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \
conv=notrunc status=none
cp /tmp/src "$FILE"
# Populate FS-Cache, then discard the page cache.
sync
echo 1 > /proc/sys/vm/drop_caches
cat "$FILE" > /dev/null
sync
echo 1 > /proc/sys/vm/drop_caches
fallocate --zero-range -o 1M -l 1M "$FILE"
if cmp -s /tmp/expected "$FILE"; then
echo "readback: OK"
else
echo "readback: STALE DATA"
fi
'
Before this change, the readback differs from /tmp/expected:
readback: STALE DATA
After this change, it matches:
readback: OK
Fixes: 30175628bf ("[SMB3] Enable fallocate -z support for SMB3 mounts")
Fixes: 31742c5a33 ("enable fallocate punch hole ("fallocate -p") for SMB3")
Fixes: 5476b5dd82 ("cifs: add support for FALLOC_FL_COLLAPSE_RANGE")
Fixes: 7fe6fe95b9 ("cifs: add FALLOC_FL_INSERT_RANGE support")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Suggested-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
smb3_insert_range() and smb3_collapse_range() use
truncate_pagecache_range() to invalidate the affected page cache.
However, if off or old_eof is not page-aligned, the boundary pages are
only partially zeroed and remain uptodate. As a result, the client may
return stale data after a successful insert/collapse range operation.
For example, with 4K pages:
page 0 page 1 page 2
0------4K 4K------8K 8K------12K
^ ^
off=2K old_eof=10K
Page 1 is removed from the page cache, while the boundary pages are
only partially zeroed. After COPYCHUNK moves the data on the server,
these cached pages may still return stale data.
This can be reproduced on a CIFS mount:
bash -c '
FILE=/mnt/scratch/repro
# Use a 6 KiB file so EOF is not page-aligned.
dd if=/dev/urandom of=/tmp/src bs=1K count=6 status=none
# Expected: a 4 KiB hole followed by the original data.
rm -f /tmp/expected
truncate -s 4K /tmp/expected
cat /tmp/src >> /tmp/expected
cp /tmp/src "$FILE"
# Prime the page cache before moving data on the server.
cat "$FILE" > /dev/null
fallocate --insert-range -o 0 -l 4K "$FILE"
if cmp -s /tmp/expected "$FILE"; then
echo "readback: OK"
else
echo "readback: STALE DATA"
fi
'
Fix this by writing back dirty data and discarding the page cache from
the start of the page containing off to EOF before moving data on the
server.
Fixes: 9c8b7a293f ("smb3: fix temporary data corruption in insert range")
Fixes: fa30a81f25 ("smb3: fix temporary data corruption in collapse range")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
smb3_collapse_range() stores the ssize_t return value of
smb2_copychunk_range() in an int. A successful copy larger than
INT_MAX is truncated to a negative value and treated as an error.
Reproducer:
MNT=/mnt/scratch
truncate -s 2056M "$MNT/file"
fallocate --collapse-range -o 1M -l 1M "$MNT/file"
Fix this by using __smb2_copychunk_range(), which reports success as
zero instead of returning the copied byte count.
Before this change, the reproducer fails with:
fallocate: fallocate failed: Success
and the file size remains unchanged at 2056 MiB. After this change, the
reproducer succeeds and the file size becomes the expected 2055 MiB.
Fixes: 5476b5dd82 ("cifs: add support for FALLOC_FL_COLLAPSE_RANGE")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
smb3_insert_range() shifts [off, EOF) right with COPYCHUNK, copying from
low to high offsets. When the ranges overlap, the copy can overwrite
source data that has not yet been copied. For a 1 MiB insert at offset 0:
offset: 0 1M 2M 3M 4M 5M
before: | A | B | C | D |
expected: | hole | A | B | C | D |
current: | hole | A | A | A | A | (corrupted)
Let x be the insertion offset, L the total length to move, delta the
insert length, and C the normal chunk size allowed by the server.
Insert range maps
[x, x + L) -> [x + delta, x + delta + L).
When delta >= L, the complete source and target ranges are disjoint, so
the normal copy order and chunk size are safe:
offset: 0 4 8 12 16 20 24 28 32
source: [--S0--][--S1--][--S2--][--S3--]
target: [--T0--][--T1--][--T2--][--T3--]
When delta < L, the complete source and target ranges overlap, so the
copy must proceed from EOF backwards. There are two subcases.
If delta >= C, each corresponding source and target chunk is disjoint.
The 1 MiB example has L = 4 MiB and delta = C = 1 MiB:
offset: 0 1M 2M 3M 4M 5M
source: [--S0--][--S1--][--S2--][--S3--]
target: [--T0--][--T1--][--T2--][--T3--]
Copying S0 from [0, 1M) to [1M, 2M) overwrites S1 before it is copied.
Processing chunks from EOF backwards prevents this inter-chunk
overwrite.
If delta < C, the source and target ranges of a normal chunk also
overlap. For example, with L = 16, delta = 2 and C = 4:
offset: 0 2 4 6 8 10 12 14 16 18
source: [--S0--][--S1--][--S2--][--S3--]
target: [--T0--][--T1--][--T2--][--T3--]
Here S0 and T0 overlap over [2,4), S1 and T1 over [6,8), and so on.
Backward ordering cannot control how the server copies bytes inside one
descriptor, so the chunk size must be limited to delta.
Fix this by copying overlapping right shifts from EOF backwards. Limit
the chunk size to delta when delta < C so that each chunk's source and
target ranges do not overlap. Using larger chunks would require a way to
identify servers that safely handle overlapping COPYCHUNK descriptors.
Therefore:
delta >= L:
keep the normal copy order and chunk size
delta < L:
delta >= C: copy backwards and keep the normal chunk size
delta < C: copy backwards and limit the chunk size to delta
Only the delta < C subcase requires reducing the chunk size for data
integrity.
Reproducer:
bash -c '
MNT=/mnt/scratch
# Generate four 1 MiB random blocks: [A][B][C][D].
dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none
# With C = 1 MiB, test delta = C and delta < C.
for delta in 1M 1K; do
truncate -s 0 /tmp/expected
truncate -s "$delta" /tmp/expected
cat /tmp/src >> /tmp/expected
cp /tmp/src "$MNT/file"
fallocate --insert-range -o 0 -l "$delta" "$MNT/file"
if cmp -s /tmp/expected "$MNT/file"; then
echo "delta=$delta: OK"
else
echo "delta=$delta: CORRUPTED"
fi
done
'
The corruption reproduces with Samba and ksmbd, while Windows handles
the overlapping COPYCHUNK ranges safely.
The 1 MiB case tests delta >= C, while the 1 KiB case tests delta < C.
Before this change, the reproducer reports:
delta=1M: CORRUPTED
delta=1K: CORRUPTED
After this change, it passes against both ksmbd and Samba:
delta=1M: OK
delta=1K: OK
Fixes: 7fe6fe95b9 ("cifs: add FALLOC_FL_INSERT_RANGE support")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
The SMB client emulates FALLOC_FL_INSERT_RANGE with SET_EOF, COPYCHUNK
and SET_ZERO_DATA.
SET_ZERO_DATA creates a hole only when the file is sparse. On a
non-sparse file, it clears the inserted range but leaves its blocks
allocated, causing the extent count check in xfstests generic/064 to
fail.
Fix this by marking the file sparse before modifying it.
This patch produces the expected sparse extents in xfstests generic/064
only when the server-reported block size is compatible with the server's
deallocation granularity.
For ksmbd, the reported block size follows the backing filesystem,
and the test passes. For Samba, the test passes with a block size
matching the backend granularity, for example, 4 KiB on Btrfs, but not
with the default 1 KiB value. For Windows Server 2022, 4 KiB inserts do
not generate holes, while aligned inserts of 64 KiB or larger do.
Fixes: 7fe6fe95b9 ("cifs: add FALLOC_FL_INSERT_RANGE support")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
When FALLOC_FL_ZERO_RANGE is used without FALLOC_FL_KEEP_SIZE,
smb3_zero_range() may extend EOF without checking RLIMIT_FSIZE, allowing
the file to grow beyond the caller's file-size limit.
Fix this by calling inode_newsize_ok() before sending the zero-range
request when the operation would extend EOF.
Reproducer, using a file on a CIFS mount:
bash -c '
FILE=/mnt/cifs/repro
trap "" SIGXFSZ
ulimit -f 3072
truncate -s 2M "$FILE"
fallocate --zero-range -o 0 -l 4M "$FILE"
echo "fallocate rc=$?"
stat -c "file size=%s" "$FILE"
'
Before this change, the operation succeeds despite the 3 MiB limit:
fallocate rc=0
file size=4194304
After this change, fallocate fails and leaves the file at 2 MiB.
Fixes: 72c419d9b0 ("cifs: fix smb3_zero_range so it can expand the file-size when required")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
smb3_insert_range() does not check if the new file size
(i_size + len) is valid. This allows FALLOC_FL_INSERT_RANGE to bypass
RLIMIT_FSIZE, exceed s_maxbytes, or produce a size outside the loff_t
range.
Use check_add_overflow() to calculate the new EOF. Validate it with
inode_newsize_ok() before modifying the file.
Reproducer, using a file on a CIFS mount:
bash -c '
FILE=/mnt/cifs/repro
trap "" SIGXFSZ
ulimit -f 3072 # RLIMIT_FSIZE = 3 MiB
# A regular write is stopped at 3 MiB.
dd if=/dev/zero of="$FILE" bs=1M count=4 status=none
stat -c "size after write: %s" "$FILE"
# Insert 2 MiB into a 2 MiB file.
truncate -s 2M "$FILE"
fallocate -i -o 0 -l 2M "$FILE"
stat -c "size after insert: %s" "$FILE"
'
Before this change, the regular write stops at the 3 MiB limit, but
insert range grows the file to 4 MiB:
dd: error writing '/mnt/cifs/repro': File too large
size after write: 3145728
size after insert: 4194304
After this change, insert range also fails at the limit and leaves the
2 MiB file unchanged:
dd: error writing '/mnt/cifs/repro': File too large
size after write: 3145728
fallocate: fallocate failed: File too large
size after insert: 2097152
Fixes: 7fe6fe95b9 ("cifs: add FALLOC_FL_INSERT_RANGE support")
Signed-off-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Everything:
Total patches: 171
Reviews/patch: 1.83
Reviewed rate: 82%
Excluding selftests:
Total patches: 149
Reviews/patch: 1.77
Reviewed rate: 80%
Excluding selftests and maple_tree:
Total patches: 129
Reviews/patch: 1.99
Reviewed rate: 89%
Summary of patch series in this merge:
- "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff"
(Lorenzo Stoakes):
Index MAP_PRIVATE file-backed folios by their anonymous page offset to
resolve confusion around reverse mapping for zeroed and CoW'd
file-backed memory.
Use this new VMA anonymous page offset tracking to eliminate index
conflicts and lay the foundation for scalable CoW performance
improvements.
- "promote mapped executable folios after first usage for MGLRU" (Baolin
Wang):
Make MGLRU's protection of mapped executable file folios more
reliable. Follow the classical LRU's logic, promoting mapped executable
file folios after their first usage to give executable code a better
chance to stay in memory and improve workload performance.
- "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen):
Fix per-node proactive reclaim interface's ignoring the swappiness
parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness()
into a single function that checks proactive_swappiness regardless of
kernel configuration.
- "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance
cost" (Usama Arif):
Reduce lru_lock contention in the reclaim path by deriving
scan-balance costs from vmstat counters rather than lock-acquired
producer updates.
Read and decay these cost signals on the reclaim side under a
dedicated per-lruvec lock, reducing total LRU lock wait time by over 60%
without impacting scan throughput.
- "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky):
Fix two low-risk zram bugs which Sashiko spotted in drive-by review.
- "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's
memcg" (Zi Yan):
Fix xas_split_alloc() by enabling target folio memcg charging during
splits and adding the missing __GFP_ACCOUNT flag for proper XArray node
memory accounting.
- "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick):
Replace hardcoded binary names in selftests/mm/.gitignore with a
generic pattern-matching rule to automatically ignore generated test
files and avoid manual updates when adding new tests.
- "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon):
Make the incompatibility between FLATMEM and NUMA explicit in
mm/Kconfig and remove the unused pgdat_page_ext_init() function.
- "zram: fix zstd error paths and add parameter validation" (Haoqin Huang):
Clean up zram compression backends by removing redundant error
cleanup, adding parameter and dictionary validation, auto-prefixing
algorithm error logs, and resetting parameters prior to
reinitialization.
- "zram: fix stale scan bounds after reinitialization" (Longlong Xia):
Prevent out-of-bounds slot accesses during concurrent zram resets by
moving table scan bound calculations under dev_lock in writeback_store()
and read_block_state().
- "add anon mTHP collapse test cases" (Baolin Wang):
Extend selftests helper functions to support arbitrary page orders and
add new test cases and options for mTHP collapse in khugepaged.
- "selftests/mm: Handle unsupported and transient test conditions"
(Muhammad Usama Anjum):
Update MM selftests to report a SKIP status instead of a failure when
required kernel or filesystem features are unsupported, while adding
retry logic for transient page migration errors.
- "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia):
Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled
and extend shrink_memcg() to support batch writeback for improved
writeback efficiency.
- "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan):
Introduce an IOCTL-based binary interface for memory allocation
profiling that enables kernel-side filtering before per-CPU counter
aggregation.
This eliminates the text-parsing overhead of /proc/allocinfo and
provides up to a 20x speedup by transferring only filtered allocation
data to userspace.
- "better block swap batching and a different take on swap_ops v5"
(Christoph Hellwig):
Refactor block swap I/O to use swap_iocb for batching instead of
single-bio requests and rebase the swap_ops interface, achieving faster
swap throughput during kernel builds.
- "mm: kmemleak: reduce transient false positives by confirming leaks"
(Catalin Marinas):
Reduce false-positive kmemleak reports by combining two kmemleak
enhancements that add a second confirmation scan and a configurable
minimum unreferenced scan count module parameter.
- "mm: kmemleak: default min_unref_scans to 2 for verbose kernels"
(Breno Leitao):
Auto-scanning kernels can generate false-positive memory leak reports
on single scans, so this patch defaults min_unref_scans to 2 when
CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming
scan.
- "swap_ops updates" (Christoph Hellwig):
Batching I/O for synchronous swap devices causes performance
regressions and filesystem-based swap suffers from double-indirection
overhead. This series resolves both issues by reintroducing per-folio
writes for synchronous swap and allowing filesystems to directly export
their own swap_ops.
- "mm/khugepaged: several cleanups" (Nico Pache):
khugepaged accumulated redundant state-checking patterns and outdated
comments following mTHP integration. Introduce dedicated helpers for
PTE validation and event counting while refreshing the internal
documentation.
- "maple_tree: lock checking and clean ups" (Liam Howlett):
Syzbot reports incorrectly blame memory management exit paths for
locking bugs, maple tree erase operations risk allocation failures
without gfp flags and internal documentation lacks clarity.
Improve lock error detection, update docs, fix race and allocation
edge cases and optimize erase allocations using a fallback to GFP_KERNEL
| GFP_NOFAIL.
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Merge tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:
- "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff"
(Lorenzo Stoakes)
Index MAP_PRIVATE file-backed folios by their anonymous page offset
to resolve confusion around reverse mapping for zeroed and CoW'd
file-backed memory.
Use this new VMA anonymous page offset tracking to eliminate index
conflicts and lay the foundation for scalable CoW performance
improvements.
- "promote mapped executable folios after first usage for MGLRU"
(Baolin Wang)
Make MGLRU's protection of mapped executable file folios more
reliable. Follow the classical LRU's logic, promoting mapped
executable file folios after their first usage to give executable
code a better chance to stay in memory and improve workload
performance.
- "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong
Chen)
Fix per-node proactive reclaim interface's ignoring the swappiness
parameter when CONFIG_MEMCG is disabled by consolidating
sc_swappiness() into a single function that checks
proactive_swappiness regardless of kernel configuration.
- "mm/vmscan: reduce lru_lock contention via vmstat-derived
scan-balance cost" (Usama Arif)
Reduce lru_lock contention in the reclaim path by deriving
scan-balance costs from vmstat counters rather than lock-acquired
producer updates.
Read and decay these cost signals on the reclaim side under a
dedicated per-lruvec lock, reducing total LRU lock wait time by over
60% without impacting scan throughput.
- "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky)
Fix two low-risk zram bugs which Sashiko spotted in drive-by review.
- "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's
memcg" (Zi Yan)
Fix xas_split_alloc() by enabling target folio memcg charging during
splits and adding the missing __GFP_ACCOUNT flag for proper XArray
node memory accounting.
- "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick)
Replace hardcoded binary names in selftests/mm/.gitignore with a
generic pattern-matching rule to automatically ignore generated test
files and avoid manual updates when adding new tests.
- "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon)
Make the incompatibility between FLATMEM and NUMA explicit in
mm/Kconfig and remove the unused pgdat_page_ext_init() function.
- "zram: fix zstd error paths and add parameter validation" (Haoqin
Huang)
Clean up zram compression backends by removing redundant error
cleanup, adding parameter and dictionary validation, auto-prefixing
algorithm error logs, and resetting parameters prior to
reinitialization.
- "zram: fix stale scan bounds after reinitialization" (Longlong Xia)
Prevent out-of-bounds slot accesses during concurrent zram resets by
moving table scan bound calculations under dev_lock in
writeback_store() and read_block_state().
- "add anon mTHP collapse test cases" (Baolin Wang)
Extend selftests helper functions to support arbitrary page orders
and add new test cases and options for mTHP collapse in khugepaged.
- "selftests/mm: Handle unsupported and transient test conditions"
(Muhammad Usama Anjum)
Update MM selftests to report a SKIP status instead of a failure when
required kernel or filesystem features are unsupported, while adding
retry logic for transient page migration errors.
- "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia)
Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled
and extend shrink_memcg() to support batch writeback for improved
writeback efficiency.
- "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren
Baghdasaryan)
Introduce an IOCTL-based binary interface for memory allocation
profiling that enables kernel-side filtering before per-CPU counter
aggregation.
This eliminates the text-parsing overhead of /proc/allocinfo and
provides up to a 20x speedup by transferring only filtered allocation
data to userspace.
- "better block swap batching and a different take on swap_ops v5"
(Christoph Hellwig)
Refactor block swap I/O to use swap_iocb for batching instead of
single-bio requests and rebase the swap_ops interface, achieving
faster swap throughput during kernel builds.
- "mm: kmemleak: reduce transient false positives by confirming leaks"
(Catalin Marinas)
Reduce false-positive kmemleak reports by combining two kmemleak
enhancements that add a second confirmation scan and a configurable
minimum unreferenced scan count module parameter.
- "mm: kmemleak: default min_unref_scans to 2 for verbose kernels"
(Breno Leitao)
Auto-scanning kernels can generate false-positive memory leak reports
on single scans, so this patch defaults min_unref_scans to 2 when
CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second
confirming scan.
- "swap_ops updates" (Christoph Hellwig)
Batching I/O for synchronous swap devices causes performance
regressions and filesystem-based swap suffers from double-indirection
overhead. This series resolves both issues by reintroducing per-folio
writes for synchronous swap and allowing filesystems to directly
export their own swap_ops.
- "mm/khugepaged: several cleanups" (Nico Pache)
khugepaged accumulated redundant state-checking patterns and outdated
comments following mTHP integration. Introduce dedicated helpers for
PTE validation and event counting while refreshing the internal
documentation.
- "maple_tree: lock checking and clean ups" (Liam Howlett)
Syzbot reports incorrectly blame memory management exit paths for
locking bugs, maple tree erase operations risk allocation failures
without gfp flags and internal documentation lacks clarity.
Improve lock error detection, update docs, fix race and allocation
edge cases and optimize erase allocations using a fallback to
GFP_KERNEL | GFP_NOFAIL.
* tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits)
selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC
memcg: move LRU size accounting on reparenting instead of copying it
mm/vmscan: fix comment logic in balance_pgdat
maple_tree: add helper mas_make_walkable()
maple_tree: avoid extra gap calculation
maple_tree: fix argument name in header
maple_tree: change two GFP flags in tests
maple_tree: document erase and allocations better
maple_tree: avoid mas_erase() and mtree_erase() failures
maple_tree: document that erase may use GFP_KERNEL for allocations
maple_tree: catch race in mas_alloc_cyclic()
maple_tree: add bulk parent set helper
maple_tree: micro optimisation of mas_wr_store_type()
maple_tree: optimise mas_wr_node_store() when not in rcu mode
maple_tree: use prefetched value in mas_wr_store_type()
maple_tree: clarify comments on mas_nomem()
maple_tree: drop MAPLE_ALLOC_SLOTS
maple_tree: drop dead code from mas_extend_spanning_null()
maple_tree: documentation fix
maple_tree: add write lock checking with lockdep sequence numbers
...
smb2_duplicate_extents() has no handling for
FSCTL_DUPLICATE_EXTENTS_TO_FILE failure: when the FSCTL fails, local
inode metadata may be stale from the pre-extension or from concurrent
remote writes, but is never refreshed.
Force revalidation on FSCTL failure and use i_size_read() for the
pre-extension check.
Fixes: cfc63fc812 ("smb3: fix cached file size problems in duplicate extents (reflink)")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Currently swap to and from file systems goes through two indirect calls
between the swap ops and the swap_rw method. Reduce this by directly
providing the swap_ops from the file system.
For this refactor swap_fs_submit into a swap_fs_prepare_rw helper that
initializes the iov_iter on the callers stack so that file systems can
call it directly, and use that to initialize file system specific ops in
the NFS and SMB clients, which then get passed to swap_fs_activate.
Link: https://lore.kernel.org/20260723054622.3460249-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Steve French <sfrench@samba.org>
Cc: Usama Arif <usama.arif@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Provide a swap_fs_activate helper that directly sets up swap_fs_ops, and a
flag in struct swap_ops to indicate of NOFS swapping is allowed.
Link: https://lore.kernel.org/20260713093350.2154226-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Youngjun Park <youngjun.park@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- five sensitive data leak fixes (clear stack and heap cryptographic
keys/hashes)
- six file size and cache synchronization fixes (fscache cookie
serialization and truncation handling)
- seven protocol validation and buffer safety fixes (prevent OOB
access and loff_t underflow)
- six metadata and POSIX attribute fixes (proper hard-link counts and
setuid/setgid stripping)
- three DFS cache and unmount fixes (prevent target-hint UAF and
unmount hangs)
- six general client improvements (fix read request leaks, stats
loops, handle servers that don't support O_TMPFILE)
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Merge tag 'cifs-fixes-7.3-rc1' of https://git.manguebit.org/linux
Pull smb client updates from Paulo Alcantara:
- clear sensitive data after use (stack and heap cryptographic
keys/hashes)
- file size and cache synchronization fixes (fscache cookie
serialization and truncation handling)
- protocol validation and buffer safety fixes (prevent OOB access and
loff_t underflow)
- metadata and POSIX attribute fixes (proper hard-link counts and
setuid/setgid stripping)
- DFS cache and unmount fixes (prevent target-hint UAF and unmount
hangs)
- general client improvements (fix read request leaks, stats loops,
handle servers that don't support O_TMPFILE)
* tag 'cifs-fixes-7.3-rc1' of https://git.manguebit.org/linux: (33 commits)
cifs: fix loff_t underflow in cifs_remap_file_range() when len == 0
smb: client: reject a tree connect response whose byte count is too small
cifs: call pagecache_isize_extended() in cifs_setsize() when extending
smb: client: fix copy-paste error in WSL EA length accounting for $LXDEV
smb: client: remove redundant NULL check before kfree()
smb: client: restore the data_offset bound in is_valid_oplock_break()
cifs: clear tcon after cifsFileInfo_put() in cifs_file_set_size()
smb: client: Avoid leaking sensitive data to the heap in connect.c
smb: client: Clear sensitive stack data in smb1encrypt.c
smb: client: Clear sensitive stack data in cifsencrypt.c
smb: client: Clear sensitive stack and heap data in smb2ops.c
smb: client: Clear sensitive stack data in smb2transport.c
Revert "cifs: remove all cifs files before kill super"
smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr()
smb: client: fix ALIGN() overflow in symlink_data() error context loop
smb: client: simplify __build_path_from_dentry_optional_prefix()
smb: client: fix UAF and buffer leak in cifs_check_trans2() for malformed secondary T2
smb: client: fix OOB read/write from unvalidated DataOffset in coalesce_t2()
smb/client: decode reparse metadata using its payload type
smb/client: preserve open info type across compound queries
...
With len == 0 (clone to EOF), the effective length is computed as:
len = src_inode->i_size - off;
If off > i_size, this is a negative loff_t, corrupting the ByteCount
in the FSCTL_DUPLICATE_EXTENTS_TO_FILE request and inverting the range
in filemap_write_and_wait_range(). The existing off >= i_size check
fires only after the ioctl has already been sent.
Snapshot i_size_read() once for both the bounds check and the length
calculation, eliminating the TOCTOU and 32-bit torn-read risk. Reject
off > src_size with -EINVAL. Treat off == src_size as a no-op,
consistent with __generic_remap_file_range_prep().
Fixes: 04b38d6012 ("vfs: pull btrfs clone API to vfs layer")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
CIFSTCon() bounds its strnlen() over the byte area with the server's
ByteCount minus two, which for ByteCount 0 or 1 goes negative as an int
and converts to a huge size_t. The later subtraction wraps the __u16
bytes_left, and that is what bounds cifs_strndup_from_utf16(): a bound of
up to 65535 against a ~16 KB cifs_req_poolp object runs off the end of the
slab object, and the bytes reach userspace through tcon->nativeFileSystem
in /proc/fs/cifs/DebugData.
Reject a byte area too small for what the parser consumes. Two bytes is
the least it can consume, and no conformant response carries fewer. The
new trace point is the 129th smb_eio_trace entry, which __mode(byte)
cannot represent, so the attribute goes with it.
Fixes: cc20c031bb ("cifs: convert CIFSTCon to use new unicode helper functions")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
cifs_setsize() calls truncate_pagecache() but skips
pagecache_isize_extended() on extension. truncate_setsize() shows
the correct pattern:
i_size_write(inode, newsize);
if (newsize > oldsize)
pagecache_isize_extended(inode, oldsize, newsize);
truncate_pagecache(inode, newsize);
pagecache_isize_extended() zeroes the tail of the page straddling old
EOF. Without it, dirty bytes in that region can be written back to
the server, exposing stale data in the newly extended range.
Cc: stable@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
The LXDEV block in cifs_query_path_info() uses SMB2_WSL_XATTR_MODE_SIZE
(4) instead of SMB2_WSL_XATTR_DEV_SIZE (8), undercounting eas_len by 4
bytes per $LXDEV EA.
eas_len is used only as a zero/non-zero presence flag so there is no
current functional impact, but the value is incorrect and misleading.
Fixes: 97db41604555 ("smb: client: parse uid, gid, mode and dev from WSL reparse points")
Cc: stable@vger.kernel.org
Cc: Paulo Alcantara <pc@manguebit.org>
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
kfree() safely handles NULL pointers, so the explicit NULL check
before calling kfree() is unnecessary.
This issue was reported by ifnullfree.cocci.
Signed-off-by: Mohammad Shahid <mdshahid03@gmail.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Commit 83bfbd0bb9 ("cifs: Remove the RFC1002 header from smb_hdr")
changed the quantity this bound is measured against. It used to be
srv->total_read minus the 4-byte RFC1002 preamble that total_read then
included, so it was the SMB message length. The same commit stopped
counting the preamble, and the mechanical substitution to
srv->total_read - srv->pdu_size left an expression that is identically
zero: standard_receive3() reads MID_HEADER_SIZE() bytes and then exactly
pdu_length - MID_HEADER_SIZE() more, adding both to total_read.
len is therefore 0, the subtraction below it wraps, and no __u32
DataOffset can exceed the result, so the check from commit 097f5863b1
("cifs: read overflow in is_valid_oplock_break()") no longer rejects
anything. Use total_read, which is now the message length on its own.
Fixes: 83bfbd0bb9 ("cifs: Remove the RFC1002 header from smb_hdr")
Cc: stable@kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
When the else branch of cifs_file_set_size() finds a writable file handle
via find_writable_file(), it borrows tcon and server from the handle's
tlink, attempts the handle-based set_file_size() RPC, and then releases
the handle with cifsFileInfo_put().
If set_file_size() fails, execution falls through to the path-based
fallback, which reuses the borrowed tcon and server under the
"if (tcon == NULL)" guard. Since tcon is not NULL at that point, the
guard is skipped. If cifsFileInfo_put() dropped the last reference on a
tlink that was already removed from the tlink tree (TCON_LINK_IN_TREE
cleared, as happens during reconnection or session teardown),
cifs_put_tlink() will have freed tcon; the subsequent set_path_size()
call is then a use-after-free.
Setting tcon = NULL after cifsFileInfo_put() causes the existing guard
to take the cifs_sb_tlink() path, which acquires a fresh reference for
the path-based operation or fails cleanly if the session is gone.
Fixes: 110fee6b9b ("smb: client: fix missing timestamp updates with O_TRUNC")
Cc: stable@vger.kernel.org
Cc: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
TCP_Server_Info contains a preauth_sha_hash[] and a cryptkey[] array
that might contain sensitive data. Thus free its memory with
kfree_sensitive() to avoid that we are leaking this information to
the heap.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Make sure to not leak signature data via the stack, clear it
with memzero_explicit() before leaving the function.
To avoid that we have to introduce "goto"-cleanup here, we re-arrange
the code a little bit (and drop the commented cifs_dump_mem debug
code that looks like a leftover from very early days).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Make sure to not leak hash data via the stack, clear it
with memzero_explicit() before leaving the function.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Make sure to not leak key-related data via the heap or the stack
by using kfree_sensitive() or memzero_explicit() here.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Sensitive data like keys that are stored in stack-local arrays could
be leaked via the stack to the calling functions. There is no known
vulnerability for this right now, but it's good security style to
explicitly zeroize this sensitive material as soon as possible to
avoid that it could be exploited together with other bugs later.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
This reverts commit 6d9a4aaaa8.
First, directly flushing fileinfo_put_wq in that commit cannot guarantee
that all in-flight I/O has run its cleanup_work on system_dfl_wq and
subsequently called queue_work(fileinfo_put_wq, ...). Flushing only the
latter workqueue may therefore miss puts that have not yet been queued, so
the fix is not reliable in the first place. Moreover, this fix flushes
inside cifs_umount(), which means the busy-dentry warning can still be
triggered when umount_check() is called inside kill_anon_super(), because
kill_anon_super() is executed before cifs_umount().
Second, commit 75f5c412fa ("smb: client: fix busy dentry warning on
unmount after DIO") already drains both serverclose_wq and fileinfo_put_wq
in cifs_kill_sb(), before kill_anon_super(). By adding a per-superblock
outstanding-rreq counter, it guarantees that all cleanup_work for this sb
have run, and thus all relevant cfile puts are queued on fileinfo_put_wq
or serverclose_wq.
Third, no path between those drains and cifs_umount() can queue new work
onto either workqueue. In the "cifs_sb->root == NULL" path there are no
file-related workers either, so that case is safe as well.
Therefore the busy-dentry and null-ptr-deref problems cannot arise, and
the flush added by commit 6d9a4aaaa8 ("cifs: remove all cifs files before
kill super") is redundant and can be removed.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
reparse_buf_ptr() reads buf->ReparseDataLength before checking that
count covers the full fixed header:
buf = (struct reparse_data_buffer *)((u8 *)io + off);
len = sizeof(*buf); /* 8 bytes */
rdlen = le16_to_cpu(buf->ReparseDataLength); /* offset 4, 2 bytes */
if (count < len || count < rdlen + len) /* check comes after */
struct reparse_data_buffer has ReparseDataLength at offset 4. If a
server returns OutputCount < 6, the read at offset 4-5 reaches past
the end of the received data. The off+count bounds against iov_len
were already validated, but that does not protect against count being
smaller than sizeof(*buf).
Split the check: verify count >= sizeof(*buf) before reading
ReparseDataLength, then verify count covers the data region.
Fixes: a158bb66b137 ("smb: client: optimise reparse point querying")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
The check added by commit 7d9a7f1f96 ("smb/client: fix possible
infinite loop and oob read in symlink_data()") compared the post-ALIGN
length against the remaining buffer, but ALIGN() itself can overflow:
for ErrorDataLength near UINT32_MAX (e.g. 0xFFFFFFF9), ALIGN(x, 8)
wraps to 0, so the subsequent bounds check passes, and the loop
advances by zero bytes leaving 'p' pointing into stale data.
Fix by checking the raw ErrorDataLength against the remaining space
before applying ALIGN(), then checking again after. Since raw_len is
bounded by the buffer, raw_len + 7 cannot overflow, so the second check
is an exact post-alignment bounds guard.
Fixes: 76894f3e2f ("cifs: improve symlink handling for smb2+")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
