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Pull ceph fixes from Ilya Dryomov:
"A fix for a race condition around r_parent tracking that took a long
time to track down from Alex and some fixes for potential crashes on
accessing invalid memory from Max and myself.
All marked for stable"
* tag 'ceph-for-6.17-rc6' of https://github.com/ceph/ceph-client:
libceph: fix invalid accesses to ceph_connection_v1_info
ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error
ceph: always call ceph_shift_unused_folios_left()
ceph: fix race condition where r_parent becomes stale before sending message
ceph: fix race condition validating r_parent before applying state
Pull regulator fix from Mark Brown:
"One fix for sy7636a which got confused about which device to use to
manage the lifecycle of the power good GPIO because it's looked up
from the parent device due to the way DT bindings work"
* tag 'regulator-fix-v6.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: sy7636a: fix lifecycle of power good gpio
There is a place where generic code in messenger.c is reading and
another place where it is writing to con->v1 union member without
checking that the union member is active (i.e. msgr1 is in use).
On 64-bit systems, con->v1.auth_retry overlaps with con->v2.out_iter,
so such a read is almost guaranteed to return a bogus value instead of
0 when msgr2 is in use. This ends up being fairly benign because the
side effect is just the invalidation of the authorizer and successive
fetching of new tickets.
con->v1.connect_seq overlaps with con->v2.conn_bufs and the fact that
it's being written to can cause more serious consequences, but luckily
it's not something that happens often.
Cc: stable@vger.kernel.org
Fixes: cd1a677cad99 ("libceph, ceph: implement msgr2.1 protocol (crc and secure modes)")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Pull driver core fixes from Danilo Krummrich:
- Fix UAF in cgroup pressure polling by using kernfs_get_active_of()
to prevent operations on released file descriptors
- Fix unresolved intra-doc link in the documentation of struct Device
when CONFIG_DRM != y
- Update the DMA Rust MAINTAINERS entry
* tag 'driver-core-6.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
MAINTAINERS: Update the DMA Rust entry
kernfs: Fix UAF in polling when open file is released
rust: device: fix unresolved link to drm::Device
Attach the power good gpio to the regulator device devres instead of the
parent device to fix problems if probe is run multiple times
(rmmod/insmod or some deferral).
Fixes: 8c485bedfb785 ("regulator: sy7636a: Initial commit")
Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
Reviewed-by: Alistair Francis <alistair@alistair23.me>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Message-ID: <20250906-sy7636-rsrc-v1-2-e2886a9763a7@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The function move_dirty_folio_in_page_array() was created by commit
ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method") by
moving code from ceph_writepages_start() to this function.
This new function is supposed to return an error code which is checked
by the caller (now ceph_process_folio_batch()), and on error, the
caller invokes redirty_page_for_writepage() and then breaks from the
loop.
However, the refactoring commit has gone wrong, and it by accident, it
always returns 0 (= success) because it first NULLs the pointer and
then returns PTR_ERR(NULL) which is always 0. This means errors are
silently ignored, leaving NULL entries in the page array, which may
later crash the kernel.
The simple solution is to call PTR_ERR() before clearing the pointer.
Cc: stable@vger.kernel.org
Fixes: ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method")
Link: https://lore.kernel.org/ceph-devel/aK4v548CId5GIKG1@swift.blarg.de/
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull pci fix from Bjorn Helgaas:
- Fix mvebu PCI enumeration regression caused by converting to
for_each_of_range() iterator (Klaus Kudielka)
* tag 'pci-v6.17-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI: mvebu: Fix use of for_each_of_range() iterator
Update the DMA Rust maintainers entry in the following two aspects:
(1) Change Abdiel's entry to 'Reviewer'.
(2) Take patches through the driver-core tree.
Abdiel won't do any more maintainer work on the DMA (or scatterlist)
infrastructure, but he'd like to be kept in the loop, hence change is
entry to 'R:'.
Analogous to [1], the DMA (and scatterlist) helpers are closely coupled
with the core device infrastructure and the device lifecycle, hence take
patches through the driver-core tree by default.
Cc: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Link: https://lore.kernel.org/r/20250725202840.2251768-1-ojeda@kernel.org [1]
Acked-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The function ceph_process_folio_batch() sets folio_batch entries to
NULL, which is an illegal state. Before folio_batch_release() crashes
due to this API violation, the function ceph_shift_unused_folios_left()
is supposed to remove those NULLs from the array.
However, since commit ce80b76dd327 ("ceph: introduce
ceph_process_folio_batch() method"), this shifting doesn't happen
anymore because the "for" loop got moved to ceph_process_folio_batch(),
and now the `i` variable that remains in ceph_writepages_start()
doesn't get incremented anymore, making the shifting effectively
unreachable much of the time.
Later, commit 1551ec61dc55 ("ceph: introduce ceph_submit_write()
method") added more preconditions for doing the shift, replacing the
`i` check (with something that is still just as broken):
- if ceph_process_folio_batch() fails, shifting never happens
- if ceph_move_dirty_page_in_page_array() was never called (because
ceph_process_folio_batch() has returned early for some of various
reasons), shifting never happens
- if `processed_in_fbatch` is zero (because ceph_process_folio_batch()
has returned early for some of the reasons mentioned above or
because ceph_move_dirty_page_in_page_array() has failed), shifting
never happens
Since those two commits, any problem in ceph_process_folio_batch()
could crash the kernel, e.g. this way:
BUG: kernel NULL pointer dereference, address: 0000000000000034
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: Oops: 0002 [#1] SMP NOPTI
CPU: 172 UID: 0 PID: 2342707 Comm: kworker/u778:8 Not tainted 6.15.10-cm4all1-es #714 NONE
Hardware name: Dell Inc. PowerEdge R7615/0G9DHV, BIOS 1.6.10 12/08/2023
Workqueue: writeback wb_workfn (flush-ceph-1)
RIP: 0010:folios_put_refs+0x85/0x140
Code: 83 c5 01 39 e8 7e 76 48 63 c5 49 8b 5c c4 08 b8 01 00 00 00 4d 85 ed 74 05 41 8b 44 ad 00 48 8b 15 b0 >
RSP: 0018:ffffb880af8db778 EFLAGS: 00010207
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000003
RDX: ffffe377cc3b0000 RSI: 0000000000000000 RDI: ffffb880af8db8c0
RBP: 0000000000000000 R08: 000000000000007d R09: 000000000102b86f
R10: 0000000000000001 R11: 00000000000000ac R12: ffffb880af8db8c0
R13: 0000000000000000 R14: 0000000000000000 R15: ffff9bd262c97000
FS: 0000000000000000(0000) GS:ffff9c8efc303000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000034 CR3: 0000000160958004 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
<TASK>
ceph_writepages_start+0xeb9/0x1410
The crash can be reproduced easily by changing the
ceph_check_page_before_write() return value to `-E2BIG`.
(Interestingly, the crash happens only if `huge_zero_folio` has
already been allocated; without `huge_zero_folio`,
is_huge_zero_folio(NULL) returns true and folios_put_refs() skips NULL
entries instead of dereferencing them. That makes reproducing the bug
somewhat unreliable. See
https://lore.kernel.org/20250826231626.218675-1-max.kellermann@ionos.com
for a discussion of this detail.)
My suggestion is to move the ceph_shift_unused_folios_left() to right
after ceph_process_folio_batch() to ensure it always gets called to
fix up the illegal folio_batch state.
Cc: stable@vger.kernel.org
Fixes: ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method")
Link: https://lore.kernel.org/ceph-devel/aK4v548CId5GIKG1@swift.blarg.de/
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull drm fixes from Dave Airlie:
"Weekly pull fixes for drm, mostly amdgpu and xe, with a revert for
nouveau and some maintainers updates, and misc bits, doesn't seem too
out of the normal.
MAINTAINERS:
- add rust tree to MAINTAINERS
- fix X entries for nova/nouveau
nova:
- depend on 64-bit
i915:
- Fix size for for_each_set_bit() in abox iteration
xe:
- Don't touch survivability_mode on fini
- Fixes around eviction and suspend
- Extend Wa_13011645652 to PTL-H, WCL
amdgpu:
- PSP 11.x fix
- DPCD quirk handing fix
- DCN 3.5 PG fix
- Audio suspend fix
- OEM i2c clean up fix
- Module unload memory leak fix
- DC delay fix
- ISP firmware fix
- VCN fixes
amdkfd:
- P2P topology fix
- APU mem limit calculation fix
mediatek:
- fix potential OF node use-after-free
panthor:
- out-of-bounds check
nouveau:
- revert waitqueue removal for sched teardown
* tag 'drm-fixes-2025-09-12' of https://gitlab.freedesktop.org/drm/kernel: (25 commits)
MAINTAINERS: drm-misc: fix X: entries for nova/nouveau
drm/mediatek: clean up driver data initialisation
drm/mediatek: fix potential OF node use-after-free
drm/amdgpu/vcn: Allow limiting ctx to instance 0 for AV1 at any time
drm/amdgpu/vcn4: Fix IB parsing with multiple engine info packages
drm/amd/amdgpu: Declare isp firmware binary file
drm/amd/display: use udelay rather than fsleep
drm/amdgpu: fix a memory leak in fence cleanup when unloading
drm/xe: Extend Wa_13011645652 to PTL-H, WCL
drm/xe: Block exec and rebind worker while evicting for suspend / hibernate
drm/xe: Allow the pm notifier to continue on failure
drm/xe: Attempt to bring bos back to VRAM after eviction
drm/xe/configfs: Don't touch survivability_mode on fini
amd/amdkfd: correct mem limit calculation for small APUs
drm/amdkfd: fix p2p links bug in topology
drm/amd/display: remove oem i2c adapter on finish
drm/amd/display: Drop dm_prepare_suspend() and dm_complete()
drm/amd/display: Correct sequences and delays for DCN35 PG & RCG
drm/amd/display: Disable DPCD Probe Quirk
drm/i915/power: fix size for for_each_set_bit() in abox iteration
...
5da3d94a23c6 ("PCI: mvebu: Use for_each_of_range() iterator for parsing
"ranges"") simplified code by using the for_each_of_range() iterator, but
it broke PCI enumeration on Turris Omnia (and probably other mvebu
targets).
Issue #1:
To determine range.flags, of_pci_range_parser_one() uses bus->get_flags(),
which resolves to of_bus_pci_get_flags(), which already returns an
IORESOURCE bit field, and NOT the original flags from the "ranges"
resource.
Then mvebu_get_tgt_attr() attempts the very same conversion again. Remove
the misinterpretation of range.flags in mvebu_get_tgt_attr(), to restore
the intended behavior.
Issue #2:
The driver needs target and attributes, which are encoded in the raw
address values of the "/soc/pcie/ranges" resource. According to
of_pci_range_parser_one(), the raw values are stored in range.bus_addr and
range.parent_bus_addr, respectively. range.cpu_addr is a translated version
of range.parent_bus_addr, and not relevant here.
Use the correct range structure member, to extract target and attributes.
This restores the intended behavior.
Fixes: 5da3d94a23c6 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"")
Reported-by: Jan Palus <jpalus@fastmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220479
Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Tony Dinh <mibodhi@gmail.com>
Tested-by: Jan Palus <jpalus@fastmail.com>
Link: https://patch.msgid.link/20250907102303.29735-1-klaus.kudielka@gmail.com
A use-after-free (UAF) vulnerability was identified in the PSI (Pressure
Stall Information) monitoring mechanism:
BUG: KASAN: slab-use-after-free in psi_trigger_poll+0x3c/0x140
Read of size 8 at addr ffff3de3d50bd308 by task systemd/1
psi_trigger_poll+0x3c/0x140
cgroup_pressure_poll+0x70/0xa0
cgroup_file_poll+0x8c/0x100
kernfs_fop_poll+0x11c/0x1c0
ep_item_poll.isra.0+0x188/0x2c0
Allocated by task 1:
cgroup_file_open+0x88/0x388
kernfs_fop_open+0x73c/0xaf0
do_dentry_open+0x5fc/0x1200
vfs_open+0xa0/0x3f0
do_open+0x7e8/0xd08
path_openat+0x2fc/0x6b0
do_filp_open+0x174/0x368
Freed by task 8462:
cgroup_file_release+0x130/0x1f8
kernfs_drain_open_files+0x17c/0x440
kernfs_drain+0x2dc/0x360
kernfs_show+0x1b8/0x288
cgroup_file_show+0x150/0x268
cgroup_pressure_write+0x1dc/0x340
cgroup_file_write+0x274/0x548
Reproduction Steps:
1. Open test/cpu.pressure and establish epoll monitoring
2. Disable monitoring: echo 0 > test/cgroup.pressure
3. Re-enable monitoring: echo 1 > test/cgroup.pressure
The race condition occurs because:
1. When cgroup.pressure is disabled (echo 0 > cgroup.pressure), it:
- Releases PSI triggers via cgroup_file_release()
- Frees of->priv through kernfs_drain_open_files()
2. While epoll still holds reference to the file and continues polling
3. Re-enabling (echo 1 > cgroup.pressure) accesses freed of->priv
epolling disable/enable cgroup.pressure
fd=open(cpu.pressure)
while(1)
...
epoll_wait
kernfs_fop_poll
kernfs_get_active = true echo 0 > cgroup.pressure
... cgroup_file_show
kernfs_show
// inactive kn
kernfs_drain_open_files
cft->release(of);
kfree(ctx);
...
kernfs_get_active = false
echo 1 > cgroup.pressure
kernfs_show
kernfs_activate_one(kn);
kernfs_fop_poll
kernfs_get_active = true
cgroup_file_poll
psi_trigger_poll
// UAF
...
end: close(fd)
To address this issue, introduce kernfs_get_active_of() for kernfs open
files to obtain active references. This function will fail if the open file
has been released. Replace kernfs_get_active() with kernfs_get_active_of()
to prevent further operations on released file descriptors.
Fixes: 34f26a15611a ("sched/psi: Per-cgroup PSI accounting disable/re-enable interface")
Cc: stable <stable@kernel.org>
Reported-by: Zhang Zhaotian <zhangzhaotian@huawei.com>
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20250822070715.1565236-2-chenridong@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 fixes from Borislav Petkov:
- Convert the SSB mitigation to the attack vector controls which got
forgotten at the time
- Prevent the CPUID topology hierarchy detection on AMD from
overwriting the correct initial APIC ID
- Fix the case of a machine shipping without microcode in the BIOS, in
the AMD microcode loader
- Correct the Pentium 4 model range which has a constant TSC
* tag 'x86_urgent_for_v6.17_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bugs: Add attack vector controls for SSB
x86/cpu/topology: Use initial APIC ID from XTOPOLOGY leaf on AMD/HYGON
x86/microcode/AMD: Handle the case of no BIOS microcode
x86/cpu/intel: Fix the constant_tsc model check for Pentium 4
When the parent directory's i_rwsem is not locked, req->r_parent may become
stale due to concurrent operations (e.g. rename) between dentry lookup and
message creation. Validate that r_parent matches the encoded parent inode
and update to the correct inode if a mismatch is detected.
[ idryomov: folded a follow-up fix from Alex to drop extra reference
from ceph_get_reply_dir() in ceph_fill_trace():
ceph_get_reply_dir() may return a different, referenced inode when
r_parent is stale and the parent directory lock is not held.
ceph_fill_trace() used that inode but failed to drop the reference
when it differed from req->r_parent, leaking an inode reference.
Keep the directory inode in a local variable and iput() it at
function end if it does not match req->r_parent. ]
Cc: stable@vger.kernel.org
Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull smb client fixes from Steve French:
"Two smb3 client fixes, both for stable:
- Fix encryption problem with multiple compounded ops
- Fix rename error cases that could lead to data corruption"
* tag 'v6.17-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: fix data loss due to broken rename(2)
smb: client: fix compound alignment with encryption