commit 54f9d645a5 upstream.
The entry of the validators table for UAC3 AC header descriptor is
defined with the wrong protocol version UAC_VERSION_2, while it should
have been UAC_VERSION_3. This results in the validator never matching
for actual UAC3 devices (protocol == UAC_VERSION_3), causing their
header descriptors to bypass validation entirely. A malicious USB
device presenting a truncated UAC3 header could exploit this to cause
out-of-bounds reads when the driver later accesses unvalidated
descriptor fields.
The bug was introduced in the same commit as the recently fixed UAC3
feature unit sub-type typo, and appears to be from the same copy-paste
error when the UAC3 section was created from the UAC2 section.
Fixes: 57f8770620 ("ALSA: usb-audio: More validations of descriptor units")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jun Seo <jun.seo.93@proton.me>
Link: https://patch.msgid.link/20260226010820.36529-1-jun.seo.93@proton.me
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a4b0bf6a40 upstream.
efi_free_boot_services() frees memory occupied by EFI_BOOT_SERVICES_CODE
and EFI_BOOT_SERVICES_DATA using memblock_free_late().
There are two issue with that: memblock_free_late() should be used for
memory allocated with memblock_alloc() while the memory reserved with
memblock_reserve() should be freed with free_reserved_area().
More acutely, with CONFIG_DEFERRED_STRUCT_PAGE_INIT=y
efi_free_boot_services() is called before deferred initialization of the
memory map is complete.
Benjamin Herrenschmidt reports that this causes a leak of ~140MB of
RAM on EC2 t3a.nano instances which only have 512MB or RAM.
If the freed memory resides in the areas that memory map for them is
still uninitialized, they won't be actually freed because
memblock_free_late() calls memblock_free_pages() and the latter skips
uninitialized pages.
Using free_reserved_area() at this point is also problematic because
__free_page() accesses the buddy of the freed page and that again might
end up in uninitialized part of the memory map.
Delaying the entire efi_free_boot_services() could be problematic
because in addition to freeing boot services memory it updates
efi.memmap without any synchronization and that's undesirable late in
boot when there is concurrency.
More robust approach is to only defer freeing of the EFI boot services
memory.
Split efi_free_boot_services() in two. First efi_unmap_boot_services()
collects ranges that should be freed into an array then
efi_free_boot_services() later frees them after deferred init is complete.
Link: https://lore.kernel.org/all/ec2aaef14783869b3be6e3c253b2dcbf67dbc12a.camel@kernel.crashing.org
Fixes: 916f676f8d ("x86, efi: Retain boot service code until after switching to virtual mode")
Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ecfa6f3449 upstream.
In commit 2ff5baa9b5 ("HID: appleir: Fix potential NULL dereference at
raw event handle"), we handle the fact that raw event callbacks
can happen even for a HID device that has not been "claimed" causing a
crash if a broken device were attempted to be connected to the system.
Fix up the remaining in-tree HID drivers that forgot to add this same
check to resolve the same issue.
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <bentiss@kernel.org>
Cc: Bastien Nocera <hadess@hadess.net>
Cc: linux-input@vger.kernel.org
Cc: stable <stable@kernel.org>
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e446fd058 upstream.
If a broken ucan device gets a message with the message length field set
to 0, then the driver will loop for forever in
ucan_read_bulk_callback(), hanging the system. If the length is 0, just
skip the message and go on to the next one.
This has been fixed in the kvaser_usb driver in the past in commit
0c73772cd2 ("can: kvaser_usb: leaf: Fix potential infinite loop in
command parsers"), so there must be some broken devices out there like
this somewhere.
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Vincent Mailhol <mailhol@kernel.org>
Cc: stable@kernel.org
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026022319-huff-absurd-6a18@gregkh
Fixes: 9f2d3eae88 ("can: ucan: add driver for Theobroma Systems UCAN devices")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 38a01c9700 upstream.
When looking at the data in a USB urb, the actual_length is the size of
the buffer passed to the driver, not the transfer_buffer_length which is
set by the driver as the max size of the buffer.
When parsing the messages in ems_usb_read_bulk_callback() properly check
the size both at the beginning of parsing the message to make sure it is
big enough for the expected structure, and at the end of the message to
make sure we don't overflow past the end of the buffer for the next
message.
Cc: Vincent Mailhol <mailhol@kernel.org>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: stable@kernel.org
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026022316-answering-strainer-a5db@gregkh
Fixes: 702171adee ("ems_usb: Added support for EMS CPC-USB/ARM7 CAN/USB interface")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bfbc0b5b32 upstream.
dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the
DVR device. dvb_ringbuffer_init() calls init_waitqueue_head(), which
reinitializes the waitqueue list head to empty.
Since dmxdev->dvr_buffer.queue is a shared waitqueue (all opens of the
same DVR device share it), this orphans any existing waitqueue entries
from io_uring poll or epoll, leaving them with stale prev/next pointers
while the list head is reset to {self, self}.
The waitqueue and spinlock in dvr_buffer are already properly
initialized once in dvb_dmxdev_init(). The open path only needs to
reset the buffer data pointer, size, and read/write positions.
Replace the dvb_ringbuffer_init() call in dvb_dvr_open() with direct
assignment of data/size and a call to dvb_ringbuffer_reset(), which
properly resets pread, pwrite, and error with correct memory ordering
without touching the waitqueue or spinlock.
Cc: stable@vger.kernel.org
Fixes: 34731df288 ("V4L/DVB (3501): Dmxdev: use dvb_ringbuffer")
Reported-by: syzbot+ab12f0c08dd7ab8d057c@syzkaller.appspotmail.com
Tested-by: syzbot+ab12f0c08dd7ab8d057c@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/698a26d3.050a0220.3b3015.007d.GAE@google.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3ef07651a5 ]
`amdgpu_gmc_get_vbios_allocations` has a special case for how to
bring up yellow carp when amdgpu discovery is turned off. As this ASIC
ships with discovery turned on, it's generally dead code and worse it
causes `adev->mman.keep_stolen_vga_memory` to not be initialized for
yellow carp.
Remove it.
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: 096bb75e13 ("drm/amdgpu: keep vga memory on MacBooks with switchable graphics")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c7d9be66b7 ]
Commit 8c14f9c703 ("ARCNET: add com20020 PCI IDs with metadata")
converted the com20020-pci driver to use a card info structure instead
of a single flag mask in driver_data. However, it failed to take into
account that in the original code, driver_data of 0 indicates a card
with no special flags, not a card that should not have any card info
structure. This introduced a null pointer dereference when cards with
no flags were probed.
Commit bd6f1fd5d3 ("net: arcnet: com20020: Fix null-ptr-deref in
com20020pci_probe()") then papered over this issue by rejecting cards
with no driver_data instead of resolving the problem at its source.
Fix the original issue by introducing a new card info structure for
2.5Mbit cards that does not set any flags and using it if no
driver_data is present.
Fixes: 8c14f9c703 ("ARCNET: add com20020 PCI IDs with metadata")
Fixes: bd6f1fd5d3 ("net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()")
Cc: stable@vger.kernel.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Link: https://patch.msgid.link/20260213045510.32368-1-enelsonmoore@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f7afda7fcd ]
The commit 6a23e7b433 ("drm/amd: Clean up kfd node on surprise
disconnect") introduced early KFD cleanup when drm_dev_is_unplugged()
returns true. However, this causes hangs during normal module unload
(rmmod amdgpu).
The issue occurs because drm_dev_unplug() is called in amdgpu_pci_remove()
for all removal scenarios, not just surprise disconnects. This was done
intentionally in commit 39934d3ed5 ("Revert "drm/amdgpu: TA unload
messages are not actually sent to psp when amdgpu is uninstalled"") to
fix IGT PCI software unplug test failures. As a result,
drm_dev_is_unplugged() returns true even during normal module unload,
triggering the early KFD cleanup inappropriately.
The correct check should distinguish between:
- Actual surprise disconnect (eGPU unplugged): pci_dev_is_disconnected()
returns true
- Normal module unload (rmmod): pci_dev_is_disconnected() returns false
Replace drm_dev_is_unplugged() with pci_dev_is_disconnected() to ensure
the early cleanup only happens during true hardware disconnect events.
Cc: stable@vger.kernel.org
Reported-by: Cal Peake <cp@absolutedigital.net>
Closes: https://lore.kernel.org/all/b0c22deb-c0fa-3343-33cf-fd9a77d7db99@absolutedigital.net/
Fixes: 6a23e7b433 ("drm/amd: Clean up kfd node on surprise disconnect")
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 87e4b043b9 ]
If the role change while we are suspended, the cdns3 driver switches to the
new mode during resume. However, switching to host mode in this context
causes a NULL pointer dereference.
The host role's start() operation registers a xhci-hcd device, but its
probe is deferred while we are in the resume path. The host role's resume()
operation assumes the xhci-hcd device is already probed, which is not the
case, leading to the dereference. Since the start() operation of the new
role is already called, the resume operation can be skipped.
So skip the resume operation for the new role if a role switch occurs
during resume. Once the resume sequence is complete, the xhci-hcd device
can be probed in case of host mode.
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000208
Mem abort info:
...
Data abort info:
...
[0000000000000208] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] SMP
Modules linked in:
CPU: 0 UID: 0 PID: 146 Comm: sh Not tainted
6.19.0-rc7-00013-g6e64f4aabfae-dirty #135 PREEMPT
Hardware name: Texas Instruments J7200 EVM (DT)
pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : usb_hcd_is_primary_hcd+0x0/0x1c
lr : cdns_host_resume+0x24/0x5c
...
Call trace:
usb_hcd_is_primary_hcd+0x0/0x1c (P)
cdns_resume+0x6c/0xbc
cdns3_controller_resume.isra.0+0xe8/0x17c
cdns3_plat_resume+0x18/0x24
platform_pm_resume+0x2c/0x68
dpm_run_callback+0x90/0x248
device_resume+0x100/0x24c
dpm_resume+0x190/0x2ec
dpm_resume_end+0x18/0x34
suspend_devices_and_enter+0x2b0/0xa44
pm_suspend+0x16c/0x5fc
state_store+0x80/0xec
kobj_attr_store+0x18/0x2c
sysfs_kf_write+0x7c/0x94
kernfs_fop_write_iter+0x130/0x1dc
vfs_write+0x240/0x370
ksys_write+0x70/0x108
__arm64_sys_write+0x1c/0x28
invoke_syscall+0x48/0x10c
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x34/0x108
el0t_64_sync_handler+0xa0/0xe4
el0t_64_sync+0x198/0x19c
Code: 52800003 f9407ca5 d63f00a0 17ffffe4 (f9410401)
---[ end trace 0000000000000000 ]---
Cc: stable <stable@kernel.org>
Fixes: 2cf2581cd2 ("usb: cdns3: add power lost support for system resume")
Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://patch.msgid.link/20260130-usb-cdns3-fix-role-switching-during-resume-v1-1-44c456852b52@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit da61439c63 ]
Make sure to drop the reference taken when looking up the EMC device and
its driver data on first set_rate().
Note that holding a reference to a device does not prevent its driver
data from going away so there is no point in keeping the reference.
Fixes: 2db04f16b5 ("clk: tegra: Add EMC clock driver")
Fixes: 6d6ef58c24 ("clk: tegra: tegra124-emc: Fix missing put_device() call in emc_ensure_emc_driver")
Cc: stable@vger.kernel.org # 4.2: 6d6ef58c24
Cc: Mikko Perttunen <mperttunen@nvidia.com>
Cc: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 24804ba508 ]
Since commit c6e126de43 ("of: Keep track of populated platform
devices") child devices will not be created by of_platform_populate()
if the devices had previously been deregistered individually so that the
OF_POPULATED flag is still set in the corresponding OF nodes.
Switch to using of_platform_depopulate() instead of open coding so that
the child devices are created if the driver is rebound.
Fixes: c6e126de43 ("of: Keep track of populated platform devices")
Cc: stable@vger.kernel.org # 3.16
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andreas Kemnade <andreas@kemnade.info>
Link: https://patch.msgid.link/20251219110714.23919-1-johan@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 418d1e74f8 ]
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231123165627.492259-11-u.kleine-koenig@pengutronix.de
Signed-off-by: Lee Jones <lee@kernel.org>
Stable-dep-of: 24804ba508 ("mfd: omap-usb-host: Fix OF populate on driver rebind")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 19ea1d3953 ]
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231123165627.492259-14-u.kleine-koenig@pengutronix.de
Signed-off-by: Lee Jones <lee@kernel.org>
Stable-dep-of: 27a8acea47 ("mfd: qcom-pm8xxx: Fix OF populate on driver rebind")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bdc56a9c46 ]
A bitmap inconsistency issue was observed during stress tests under
mixed huge-page workloads. Ext4 reported multiple e4b bitmap check
failures like:
ext4_mb_complex_scan_group:2508: group 350, 8179 free clusters as
per group info. But got 8192 blocks
Analysis and experimentation confirmed that the issue is caused by a
race condition between page migration and bitmap modification. Although
this timing window is extremely narrow, it is still hit in practice:
folio_lock ext4_mb_load_buddy
__migrate_folio
check ref count
folio_mc_copy __filemap_get_folio
folio_try_get(folio)
......
mb_mark_used
ext4_mb_unload_buddy
__folio_migrate_mapping
folio_ref_freeze
folio_unlock
The root cause of this issue is that the fast path of load_buddy only
increments the folio's reference count, which is insufficient to prevent
concurrent folio migration. We observed that the folio migration process
acquires the folio lock. Therefore, we can determine whether to take the
fast path in load_buddy by checking the lock status. If the folio is
locked, we opt for the slow path (which acquires the lock) to close this
concurrency window.
Additionally, this change addresses the following issues:
When the DOUBLE_CHECK macro is enabled to inspect bitmap-related
issues, the following error may be triggered:
corruption in group 324 at byte 784(6272): f in copy != ff on
disk/prealloc
Analysis reveals that this is a false positive. There is a specific race
window where the bitmap and the group descriptor become momentarily
inconsistent, leading to this error report:
ext4_mb_load_buddy ext4_mb_load_buddy
__filemap_get_folio(create|lock)
folio_lock
ext4_mb_init_cache
folio_mark_uptodate
__filemap_get_folio(no lock)
......
mb_mark_used
mb_mark_used_double
mb_cmp_bitmaps
mb_set_bits(e4b->bd_bitmap)
folio_unlock
The original logic assumed that since mb_cmp_bitmaps is called when the
bitmap is newly loaded from disk, the folio lock would be sufficient to
prevent concurrent access. However, this overlooks a specific race
condition: if another process attempts to load buddy and finds the folio
is already in an uptodate state, it will immediately begin using it without
holding folio lock.
Signed-off-by: Yongjian Sun <sunyongjian1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260106090820.836242-1-sunyongjian@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5eea586b47 ]
There is no need to make this a multi-page folio, so leave all the
infrastructure around it in pages. But since we're locking it, playing
with its refcount and checking whether it's uptodate, it needs to move
to the folio API.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240416172900.244637-3-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: bdc56a9c46 ("ext4: fix e4b bitmap inconsistency reports")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 99b150d84e ]
There is no need to make this a multi-page folio, so leave all the
infrastructure around it in pages. But since we're locking it, playing
with its refcount and checking whether it's uptodate, it needs to move
to the folio API.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240416172900.244637-2-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: bdc56a9c46 ("ext4: fix e4b bitmap inconsistency reports")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fcd7f96c78 ]
Although it is guided that `#mbox-cells` must be at least 1, there are
many instances of `#mbox-cells = <0>;` in the device tree. If that is
the case and the corresponding mailbox controller does not provide
`fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will
be used by default and out-of-bounds accesses could occur due to lack of
bounds check in that function.
Cc: stable@vger.kernel.org
Signed-off-by: Joonwon Kang <joonwonkang@google.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8da4988b6e ]
Use dev_err to show the error log instead of using dev_dbg.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Stable-dep-of: fcd7f96c78 ("mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit db824c1119 ]
Sorting headers alphabetically helps locating duplicates,
and makes it easier to figure out where to insert new headers.
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Stable-dep-of: fcd7f96c78 ("mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8c71c61fc6 ]
There are no concurrency problems if multiple consumers parse the
phandle, don't gratuiously protect the parsing with the mutex used
for the controllers list.
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Stable-dep-of: fcd7f96c78 ("mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 263dbd3cc8 ]
Use of_property_match_string() instead of open-coding the search. With
this, of_get_property() can be removed as there is no need to check for
"mbox-names" presence first.
This is part of a larger effort to remove callers of of_get_property()
and similar functions. of_get_property() leaks the DT property data
pointer which is a problem for dynamically allocated nodes which may
be freed.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Stable-dep-of: fcd7f96c78 ("mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6d882ea3b0 ]
When splitting an unwritten extent in the middle and converting it to
initialized in ext4_split_extent() with the EXT4_EXT_MAY_ZEROOUT and
EXT4_EXT_DATA_VALID2 flags set, it could leave a stale unwritten extent.
Assume we have an unwritten file and buffered write in the middle of it
without dioread_nolock enabled, it will allocate blocks as written
extent.
0 A B N
[UUUUUUUUUUUU] on-disk extent U: unwritten extent
[UUUUUUUUUUUU] extent status tree
[--DDDDDDDD--] D: valid data
|<- ->| ----> this range needs to be initialized
ext4_split_extent() first try to split this extent at B with
EXT4_EXT_DATA_PARTIAL_VALID1 and EXT4_EXT_MAY_ZEROOUT flag set, but
ext4_split_extent_at() failed to split this extent due to temporary lack
of space. It zeroout B to N and leave the entire extent as unwritten.
0 A B N
[UUUUUUUUUUUU] on-disk extent
[UUUUUUUUUUUU] extent status tree
[--DDDDDDDDZZ] Z: zeroed data
ext4_split_extent() then try to split this extent at A with
EXT4_EXT_DATA_VALID2 flag set. This time, it split successfully and
leave an written extent from A to N.
0 A B N
[UUWWWWWWWWWW] on-disk extent W: written extent
[UUUUUUUUUUUU] extent status tree
[--DDDDDDDDZZ]
Finally ext4_map_create_blocks() only insert extent A to B to the extent
status tree, and leave an stale unwritten extent in the status tree.
0 A B N
[UUWWWWWWWWWW] on-disk extent W: written extent
[UUWWWWWWWWUU] extent status tree
[--DDDDDDDDZZ]
Fix this issue by always cached extent status entry after zeroing out
the second part.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Cc: stable@kernel.org
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251129103247.686136-7-yi.zhang@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit feaf2a80e7 ]
When allocating blocks during within-EOF DIO and writeback with
dioread_nolock enabled, EXT4_GET_BLOCKS_PRE_IO was set to split an
existing large unwritten extent. However, EXT4_GET_BLOCKS_CONVERT was
set when calling ext4_split_convert_extents(), which may potentially
result in stale data issues.
Assume we have an unwritten extent, and then DIO writes the second half.
[UUUUUUUUUUUUUUUU] on-disk extent U: unwritten extent
[UUUUUUUUUUUUUUUU] extent status tree
|<- ->| ----> dio write this range
First, ext4_iomap_alloc() call ext4_map_blocks() with
EXT4_GET_BLOCKS_PRE_IO, EXT4_GET_BLOCKS_UNWRIT_EXT and
EXT4_GET_BLOCKS_CREATE flags set. ext4_map_blocks() find this extent and
call ext4_split_convert_extents() with EXT4_GET_BLOCKS_CONVERT and the
above flags set.
Then, ext4_split_convert_extents() calls ext4_split_extent() with
EXT4_EXT_MAY_ZEROOUT, EXT4_EXT_MARK_UNWRIT2 and EXT4_EXT_DATA_VALID2
flags set, and it calls ext4_split_extent_at() to split the second half
with EXT4_EXT_DATA_VALID2, EXT4_EXT_MARK_UNWRIT1, EXT4_EXT_MAY_ZEROOUT
and EXT4_EXT_MARK_UNWRIT2 flags set. However, ext4_split_extent_at()
failed to insert extent since a temporary lack -ENOSPC. It zeroes out
the first half but convert the entire on-disk extent to written since
the EXT4_EXT_DATA_VALID2 flag set, but left the second half as unwritten
in the extent status tree.
[0000000000SSSSSS] data S: stale data, 0: zeroed
[WWWWWWWWWWWWWWWW] on-disk extent W: written extent
[WWWWWWWWWWUUUUUU] extent status tree
Finally, if the DIO failed to write data to the disk, the stale data in
the second half will be exposed once the cached extent entry is gone.
Fix this issue by not passing EXT4_GET_BLOCKS_CONVERT when splitting
an unwritten extent before submitting I/O, and make
ext4_split_convert_extents() to zero out the entire extent range
to zero for this case, and also mark the extent in the extent status
tree for consistency.
Fixes: b8a8684502 ("ext4: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Cc: stable@kernel.org
Message-ID: <20251129103247.686136-4-yi.zhang@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Johannes Berg
Jun Seo
Kurt Borja
Thorsten Blum
Mike Rapoport (Microsoft)
Greg Kroah-Hartman
Jens Axboe
Jann Horn
Alex Deucher
Mario Limonciello
Ethan Nelson-Moore
Takashi Iwai
Gui-Dong Han
Thomas Richard (TI)
Théo Lebrun
Hongyu Xie
Johan Hovold
Shawn Lin
Uwe Kleine-König
Yongjian Sun
Matthew Wilcox (Oracle)
Gou Hao
Joonwon Kang
Anup Patel
Peng Fan
Tudor Ambarus
Rob Herring (Arm)
Zhang Yi
Yang Erkun