In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add null checker before passing variables
Checks null pointer before passing variables to functions.
This fixes 3 NULL_RETURNS issue...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add null checker before passing variables
Checks null pointer before passing variables to functions.
This fixes 3 NULL_RETURNS issues reported by Coverity.Show less |
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix NULL pointer dereference for DTN log in DCN401
When users run the command:
cat /sys/kernel/debug/dri/0/amdgpu_dm_dtn_log
The fo...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix NULL pointer dereference for DTN log in DCN401
When users run the command:
cat /sys/kernel/debug/dri/0/amdgpu_dm_dtn_log
The following NULL pointer dereference happens:
[ +0.000003] BUG: kernel NULL pointer dereference, address: NULL
[ +0.000005] #PF: supervisor instruction fetch in kernel mode
[ +0.000002] #PF: error_code(0x0010) - not-present page
[ +0.000002] PGD 0 P4D 0
[ +0.000004] Oops: 0010 [#1] PREEMPT SMP NOPTI
[ +0.000003] RIP: 0010:0x0
[ +0.000008] Code: Unable to access opcode bytes at 0xffffffffffffffd6.
[...]
[ +0.000002] PKRU: 55555554
[ +0.000002] Call Trace:
[ +0.000002] <TASK>
[ +0.000003] ? show_regs+0x65/0x70
[ +0.000006] ? __die+0x24/0x70
[ +0.000004] ? page_fault_oops+0x160/0x470
[ +0.000006] ? do_user_addr_fault+0x2b5/0x690
[ +0.000003] ? prb_read_valid+0x1c/0x30
[ +0.000005] ? exc_page_fault+0x8c/0x1a0
[ +0.000005] ? asm_exc_page_fault+0x27/0x30
[ +0.000012] dcn10_log_color_state+0xf9/0x510 [amdgpu]
[ +0.000306] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000003] ? vsnprintf+0x2fb/0x600
[ +0.000009] dcn10_log_hw_state+0xfd0/0xfe0 [amdgpu]
[ +0.000218] ? __mod_memcg_lruvec_state+0xe8/0x170
[ +0.000008] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000002] ? debug_smp_processor_id+0x17/0x20
[ +0.000003] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000002] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000002] ? set_ptes.isra.0+0x2b/0x90
[ +0.000004] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000002] ? _raw_spin_unlock+0x19/0x40
[ +0.000004] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000002] ? do_anonymous_page+0x337/0x700
[ +0.000004] dtn_log_read+0x82/0x120 [amdgpu]
[ +0.000207] full_proxy_read+0x66/0x90
[ +0.000007] vfs_read+0xb0/0x340
[ +0.000005] ? __count_memcg_events+0x79/0xe0
[ +0.000002] ? srso_alias_return_thunk+0x5/0xfbef5
[ +0.000003] ? count_memcg_events.constprop.0+0x1e/0x40
[ +0.000003] ? handle_mm_fault+0xb2/0x370
[ +0.000003] ksys_read+0x6b/0xf0
[ +0.000004] __x64_sys_read+0x19/0x20
[ +0.000003] do_syscall_64+0x60/0x130
[ +0.000004] entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ +0.000003] RIP: 0033:0x7fdf32f147e2
[...]
This error happens when the color log tries to read the gamut remap
information from DCN401 which is not initialized in the dcn401_dpp_funcs
which leads to a null pointer dereference. This commit addresses this
issue by adding a proper guard to access the gamut_remap callback in
case the specific ASIC did not implement this function.Show less |
In the Linux kernel, the following vulnerability has been resolved:
media: xc2028: avoid use-after-free in load_firmware_cb()
syzkaller reported use-after-free in load_firmware_cb() [1].
The reason is because the modul...Show moreIn the Linux kernel, the following vulnerability has been resolved:
media: xc2028: avoid use-after-free in load_firmware_cb()
syzkaller reported use-after-free in load_firmware_cb() [1].
The reason is because the module allocated a struct tuner in tuner_probe(),
and then the module initialization failed, the struct tuner was released.
A worker which created during module initialization accesses this struct
tuner later, it caused use-after-free.
The process is as follows:
task-6504 worker_thread
tuner_probe <= alloc dvb_frontend [2]
...
request_firmware_nowait <= create a worker
...
tuner_remove <= free dvb_frontend
...
request_firmware_work_func <= the firmware is ready
load_firmware_cb <= but now the dvb_frontend has been freed
To fix the issue, check the dvd_frontend in load_firmware_cb(), if it is
null, report a warning and just return.
[1]:
==================================================================
BUG: KASAN: use-after-free in load_firmware_cb+0x1310/0x17a0
Read of size 8 at addr ffff8000d7ca2308 by task kworker/2:3/6504
Call trace:
load_firmware_cb+0x1310/0x17a0
request_firmware_work_func+0x128/0x220
process_one_work+0x770/0x1824
worker_thread+0x488/0xea0
kthread+0x300/0x430
ret_from_fork+0x10/0x20
Allocated by task 6504:
kzalloc
tuner_probe+0xb0/0x1430
i2c_device_probe+0x92c/0xaf0
really_probe+0x678/0xcd0
driver_probe_device+0x280/0x370
__device_attach_driver+0x220/0x330
bus_for_each_drv+0x134/0x1c0
__device_attach+0x1f4/0x410
device_initial_probe+0x20/0x30
bus_probe_device+0x184/0x200
device_add+0x924/0x12c0
device_register+0x24/0x30
i2c_new_device+0x4e0/0xc44
v4l2_i2c_new_subdev_board+0xbc/0x290
v4l2_i2c_new_subdev+0xc8/0x104
em28xx_v4l2_init+0x1dd0/0x3770
Freed by task 6504:
kfree+0x238/0x4e4
tuner_remove+0x144/0x1c0
i2c_device_remove+0xc8/0x290
__device_release_driver+0x314/0x5fc
device_release_driver+0x30/0x44
bus_remove_device+0x244/0x490
device_del+0x350/0x900
device_unregister+0x28/0xd0
i2c_unregister_device+0x174/0x1d0
v4l2_device_unregister+0x224/0x380
em28xx_v4l2_init+0x1d90/0x3770
The buggy address belongs to the object at ffff8000d7ca2000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 776 bytes inside of
2048-byte region [ffff8000d7ca2000, ffff8000d7ca2800)
The buggy address belongs to the page:
page:ffff7fe00035f280 count:1 mapcount:0 mapping:ffff8000c001f000 index:0x0
flags: 0x7ff800000000100(slab)
raw: 07ff800000000100 ffff7fe00049d880 0000000300000003 ffff8000c001f000
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8000d7ca2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8000d7ca2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8000d7ca2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8000d7ca2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8000d7ca2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
[2]
Actually, it is allocated for struct tuner, and dvb_frontend is inside.Show less |
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix null pointer deref in dcn20_resource.c
Fixes a hang thats triggered when MPV is run on a DCN401 dGPU:
mpv --hwdec=vaapi --vo=gpu...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix null pointer deref in dcn20_resource.c
Fixes a hang thats triggered when MPV is run on a DCN401 dGPU:
mpv --hwdec=vaapi --vo=gpu --hwdec-codecs=all
and then enabling fullscreen playback (double click on the video)
The following calltrace will be seen:
[ 181.843989] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 181.843997] #PF: supervisor instruction fetch in kernel mode
[ 181.844003] #PF: error_code(0x0010) - not-present page
[ 181.844009] PGD 0 P4D 0
[ 181.844020] Oops: 0010 [#1] PREEMPT SMP NOPTI
[ 181.844028] CPU: 6 PID: 1892 Comm: gnome-shell Tainted: G W OE 6.5.0-41-generic #41~22.04.2-Ubuntu
[ 181.844038] Hardware name: System manufacturer System Product Name/CROSSHAIR VI HERO, BIOS 6302 10/23/2018
[ 181.844044] RIP: 0010:0x0
[ 181.844079] Code: Unable to access opcode bytes at 0xffffffffffffffd6.
[ 181.844084] RSP: 0018:ffffb593c2b8f7b0 EFLAGS: 00010246
[ 181.844093] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004
[ 181.844099] RDX: ffffb593c2b8f804 RSI: ffffb593c2b8f7e0 RDI: ffff9e3c8e758400
[ 181.844105] RBP: ffffb593c2b8f7b8 R08: ffffb593c2b8f9c8 R09: ffffb593c2b8f96c
[ 181.844110] R10: 0000000000000000 R11: 0000000000000000 R12: ffffb593c2b8f9c8
[ 181.844115] R13: 0000000000000001 R14: ffff9e3c88000000 R15: 0000000000000005
[ 181.844121] FS: 00007c6e323bb5c0(0000) GS:ffff9e3f85f80000(0000) knlGS:0000000000000000
[ 181.844128] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 181.844134] CR2: ffffffffffffffd6 CR3: 0000000140fbe000 CR4: 00000000003506e0
[ 181.844141] Call Trace:
[ 181.844146] <TASK>
[ 181.844153] ? show_regs+0x6d/0x80
[ 181.844167] ? __die+0x24/0x80
[ 181.844179] ? page_fault_oops+0x99/0x1b0
[ 181.844192] ? do_user_addr_fault+0x31d/0x6b0
[ 181.844204] ? exc_page_fault+0x83/0x1b0
[ 181.844216] ? asm_exc_page_fault+0x27/0x30
[ 181.844237] dcn20_get_dcc_compression_cap+0x23/0x30 [amdgpu]
[ 181.845115] amdgpu_dm_plane_validate_dcc.constprop.0+0xe5/0x180 [amdgpu]
[ 181.845985] amdgpu_dm_plane_fill_plane_buffer_attributes+0x300/0x580 [amdgpu]
[ 181.846848] fill_dc_plane_info_and_addr+0x258/0x350 [amdgpu]
[ 181.847734] fill_dc_plane_attributes+0x162/0x350 [amdgpu]
[ 181.848748] dm_update_plane_state.constprop.0+0x4e3/0x6b0 [amdgpu]
[ 181.849791] ? dm_update_plane_state.constprop.0+0x4e3/0x6b0 [amdgpu]
[ 181.850840] amdgpu_dm_atomic_check+0xdfe/0x1760 [amdgpu]Show less |
In the Linux kernel, the following vulnerability has been resolved:
net: drop bad gso csum_start and offset in virtio_net_hdr
Tighten csum_start and csum_offset checks in virtio_net_hdr_to_skb
for GSO packets.
The fun...Show moreIn the Linux kernel, the following vulnerability has been resolved:
net: drop bad gso csum_start and offset in virtio_net_hdr
Tighten csum_start and csum_offset checks in virtio_net_hdr_to_skb
for GSO packets.
The function already checks that a checksum requested with
VIRTIO_NET_HDR_F_NEEDS_CSUM is in skb linear. But for GSO packets
this might not hold for segs after segmentation.
Syzkaller demonstrated to reach this warning in skb_checksum_help
offset = skb_checksum_start_offset(skb);
ret = -EINVAL;
if (WARN_ON_ONCE(offset >= skb_headlen(skb)))
By injecting a TSO packet:
WARNING: CPU: 1 PID: 3539 at net/core/dev.c:3284 skb_checksum_help+0x3d0/0x5b0
ip_do_fragment+0x209/0x1b20 net/ipv4/ip_output.c:774
ip_finish_output_gso net/ipv4/ip_output.c:279 [inline]
__ip_finish_output+0x2bd/0x4b0 net/ipv4/ip_output.c:301
iptunnel_xmit+0x50c/0x930 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x2296/0x2c70 net/ipv4/ip_tunnel.c:813
__gre_xmit net/ipv4/ip_gre.c:469 [inline]
ipgre_xmit+0x759/0xa60 net/ipv4/ip_gre.c:661
__netdev_start_xmit include/linux/netdevice.h:4850 [inline]
netdev_start_xmit include/linux/netdevice.h:4864 [inline]
xmit_one net/core/dev.c:3595 [inline]
dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3611
__dev_queue_xmit+0x1b97/0x3c90 net/core/dev.c:4261
packet_snd net/packet/af_packet.c:3073 [inline]
The geometry of the bad input packet at tcp_gso_segment:
[ 52.003050][ T8403] skb len=12202 headroom=244 headlen=12093 tailroom=0
[ 52.003050][ T8403] mac=(168,24) mac_len=24 net=(192,52) trans=244
[ 52.003050][ T8403] shinfo(txflags=0 nr_frags=1 gso(size=1552 type=3 segs=0))
[ 52.003050][ T8403] csum(0x60000c7 start=199 offset=1536
ip_summed=3 complete_sw=0 valid=0 level=0)
Mitigate with stricter input validation.
csum_offset: for GSO packets, deduce the correct value from gso_type.
This is already done for USO. Extend it to TSO. Let UFO be:
udp[46]_ufo_fragment ignores these fields and always computes the
checksum in software.
csum_start: finding the real offset requires parsing to the transport
header. Do not add a parser, use existing segmentation parsing. Thanks
to SKB_GSO_DODGY, that also catches bad packets that are hw offloaded.
Again test both TSO and USO. Do not test UFO for the above reason, and
do not test UDP tunnel offload.
GSO packet are almost always CHECKSUM_PARTIAL. USO packets may be
CHECKSUM_NONE since commit 10154dbded6d6 ("udp: Allow GSO transmit
from devices with no checksum offload"), but then still these fields
are initialized correctly in udp4_hwcsum/udp6_hwcsum_outgoing. So no
need to test for ip_summed == CHECKSUM_PARTIAL first.
This revises an existing fix mentioned in the Fixes tag, which broke
small packets with GSO offload, as detected by kselftests.Show less |
In the Linux kernel, the following vulnerability has been resolved:
ASoC: cs-amp-lib: Fix NULL pointer crash if efi.get_variable is NULL
Call efi_rt_services_supported() to check that efi.get_variable exists
before cal...Show moreIn the Linux kernel, the following vulnerability has been resolved:
ASoC: cs-amp-lib: Fix NULL pointer crash if efi.get_variable is NULL
Call efi_rt_services_supported() to check that efi.get_variable exists
before calling it.Show less |
In the Linux kernel, the following vulnerability has been resolved:
drm/client: fix null pointer dereference in drm_client_modeset_probe
In drm_client_modeset_probe(), the return value of drm_mode_duplicate() is
assign...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/client: fix null pointer dereference in drm_client_modeset_probe
In drm_client_modeset_probe(), the return value of drm_mode_duplicate() is
assigned to modeset->mode, which will lead to a possible NULL pointer
dereference on failure of drm_mode_duplicate(). Add a check to avoid npd.Show less |
In the Linux kernel, the following vulnerability has been resolved:
serial: core: check uartclk for zero to avoid divide by zero
Calling ioctl TIOCSSERIAL with an invalid baud_base can
result in uartclk being zero, whi...Show moreIn the Linux kernel, the following vulnerability has been resolved:
serial: core: check uartclk for zero to avoid divide by zero
Calling ioctl TIOCSSERIAL with an invalid baud_base can
result in uartclk being zero, which will result in a
divide by zero error in uart_get_divisor(). The check for
uartclk being zero in uart_set_info() needs to be done
before other settings are made as subsequent calls to
ioctl TIOCSSERIAL for the same port would be impacted if
the uartclk check was done where uartclk gets set.
Oops: divide error: 0000 PREEMPT SMP KASAN PTI
RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580)
Call Trace:
<TASK>
serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576
drivers/tty/serial/8250/8250_port.c:2589)
serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502
drivers/tty/serial/8250/8250_port.c:2741)
serial8250_set_termios (drivers/tty/serial/8250/8250_port.c:2862)
uart_change_line_settings (./include/linux/spinlock.h:376
./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222)
uart_port_startup (drivers/tty/serial/serial_core.c:342)
uart_startup (drivers/tty/serial/serial_core.c:368)
uart_set_info (drivers/tty/serial/serial_core.c:1034)
uart_set_info_user (drivers/tty/serial/serial_core.c:1059)
tty_set_serial (drivers/tty/tty_io.c:2637)
tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791)
__x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907
fs/ioctl.c:893 fs/ioctl.c:893)
do_syscall_64 (arch/x86/entry/common.c:52
(discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Rule: addShow less |
In the Linux kernel, the following vulnerability has been resolved:
memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled...Show moreIn the Linux kernel, the following vulnerability has been resolved:
memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled the memcg IDs from the CSS ID space to fix the
cgroup creation failures. It introduced IDR to maintain the memcg ID
space. The IDR depends on external synchronization mechanisms for
modifications. For the mem_cgroup_idr, the idr_alloc() and idr_replace()
happen within css callback and thus are protected through cgroup_mutex
from concurrent modifications. However idr_remove() for mem_cgroup_idr
was not protected against concurrency and can be run concurrently for
different memcgs when they hit their refcnt to zero. Fix that.
We have been seeing list_lru based kernel crashes at a low frequency in
our fleet for a long time. These crashes were in different part of
list_lru code including list_lru_add(), list_lru_del() and reparenting
code. Upon further inspection, it looked like for a given object (dentry
and inode), the super_block's list_lru didn't have list_lru_one for the
memcg of that object. The initial suspicions were either the object is
not allocated through kmem_cache_alloc_lru() or somehow
memcg_list_lru_alloc() failed to allocate list_lru_one() for a memcg but
returned success. No evidence were found for these cases.
Looking more deeply, we started seeing situations where valid memcg's id
is not present in mem_cgroup_idr and in some cases multiple valid memcgs
have same id and mem_cgroup_idr is pointing to one of them. So, the most
reasonable explanation is that these situations can happen due to race
between multiple idr_remove() calls or race between
idr_alloc()/idr_replace() and idr_remove(). These races are causing
multiple memcgs to acquire the same ID and then offlining of one of them
would cleanup list_lrus on the system for all of them. Later access from
other memcgs to the list_lru cause crashes due to missing list_lru_one.Show less |
In the Linux kernel, the following vulnerability has been resolved:
tracing: Have format file honor EVENT_FILE_FL_FREED
When eventfs was introduced, special care had to be done to coordinate the
freeing of the file met...Show moreIn the Linux kernel, the following vulnerability has been resolved:
tracing: Have format file honor EVENT_FILE_FL_FREED
When eventfs was introduced, special care had to be done to coordinate the
freeing of the file meta data with the files that are exposed to user
space. The file meta data would have a ref count that is set when the file
is created and would be decremented and freed after the last user that
opened the file closed it. When the file meta data was to be freed, it
would set a flag (EVENT_FILE_FL_FREED) to denote that the file is freed,
and any new references made (like new opens or reads) would fail as it is
marked freed. This allowed other meta data to be freed after this flag was
set (under the event_mutex).
All the files that were dynamically created in the events directory had a
pointer to the file meta data and would call event_release() when the last
reference to the user space file was closed. This would be the time that it
is safe to free the file meta data.
A shortcut was made for the "format" file. It's i_private would point to
the "call" entry directly and not point to the file's meta data. This is
because all format files are the same for the same "call", so it was
thought there was no reason to differentiate them. The other files
maintain state (like the "enable", "trigger", etc). But this meant if the
file were to disappear, the "format" file would be unaware of it.
This caused a race that could be trigger via the user_events test (that
would create dynamic events and free them), and running a loop that would
read the user_events format files:
In one console run:
# cd tools/testing/selftests/user_events
# while true; do ./ftrace_test; done
And in another console run:
# cd /sys/kernel/tracing/
# while true; do cat events/user_events/__test_event/format; done 2>/dev/null
With KASAN memory checking, it would trigger a use-after-free bug report
(which was a real bug). This was because the format file was not checking
the file's meta data flag "EVENT_FILE_FL_FREED", so it would access the
event that the file meta data pointed to after the event was freed.
After inspection, there are other locations that were found to not check
the EVENT_FILE_FL_FREED flag when accessing the trace_event_file. Add a
new helper function: event_file_file() that will make sure that the
event_mutex is held, and will return NULL if the trace_event_file has the
EVENT_FILE_FL_FREED flag set. Have the first reference of the struct file
pointer use event_file_file() and check for NULL. Later uses can still use
the event_file_data() helper function if the event_mutex is still held and
was not released since the event_file_file() call.Show less |
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix overflow in get_free_elt()
"tracing_map->next_elt" in get_free_elt() is at risk of overflowing.
Once it overflows, new elements can stil...Show moreIn the Linux kernel, the following vulnerability has been resolved:
tracing: Fix overflow in get_free_elt()
"tracing_map->next_elt" in get_free_elt() is at risk of overflowing.
Once it overflows, new elements can still be inserted into the tracing_map
even though the maximum number of elements (`max_elts`) has been reached.
Continuing to insert elements after the overflow could result in the
tracing_map containing "tracing_map->max_size" elements, leaving no empty
entries.
If any attempt is made to insert an element into a full tracing_map using
`__tracing_map_insert()`, it will cause an infinite loop with preemption
disabled, leading to a CPU hang problem.
Fix this by preventing any further increments to "tracing_map->next_elt"
once it reaches "tracing_map->max_elt".Show less |
In the Linux kernel, the following vulnerability has been resolved:
padata: Fix possible divide-by-0 panic in padata_mt_helper()
We are hit with a not easily reproducible divide-by-0 panic in padata.c at
bootup time....Show moreIn the Linux kernel, the following vulnerability has been resolved:
padata: Fix possible divide-by-0 panic in padata_mt_helper()
We are hit with a not easily reproducible divide-by-0 panic in padata.c at
bootup time.
[ 10.017908] Oops: divide error: 0000 1 PREEMPT SMP NOPTI
[ 10.017908] CPU: 26 PID: 2627 Comm: kworker/u1666:1 Not tainted 6.10.0-15.el10.x86_64 #1
[ 10.017908] Hardware name: Lenovo ThinkSystem SR950 [7X12CTO1WW]/[7X12CTO1WW], BIOS [PSE140J-2.30] 07/20/2021
[ 10.017908] Workqueue: events_unbound padata_mt_helper
[ 10.017908] RIP: 0010:padata_mt_helper+0x39/0xb0
:
[ 10.017963] Call Trace:
[ 10.017968] <TASK>
[ 10.018004] ? padata_mt_helper+0x39/0xb0
[ 10.018084] process_one_work+0x174/0x330
[ 10.018093] worker_thread+0x266/0x3a0
[ 10.018111] kthread+0xcf/0x100
[ 10.018124] ret_from_fork+0x31/0x50
[ 10.018138] ret_from_fork_asm+0x1a/0x30
[ 10.018147] </TASK>
Looking at the padata_mt_helper() function, the only way a divide-by-0
panic can happen is when ps->chunk_size is 0. The way that chunk_size is
initialized in padata_do_multithreaded(), chunk_size can be 0 when the
min_chunk in the passed-in padata_mt_job structure is 0.
Fix this divide-by-0 panic by making sure that chunk_size will be at least
1 no matter what the input parameters are.Show less |
In the Linux kernel, the following vulnerability has been resolved:
mm: list_lru: fix UAF for memory cgroup
The mem_cgroup_from_slab_obj() is supposed to be called under rcu lock or
cgroup_mutex or others which could p...Show moreIn the Linux kernel, the following vulnerability has been resolved:
mm: list_lru: fix UAF for memory cgroup
The mem_cgroup_from_slab_obj() is supposed to be called under rcu lock or
cgroup_mutex or others which could prevent returned memcg from being
freed. Fix it by adding missing rcu read lock.
Found by code inspection.
[songmuchun@bytedance.com: only grab rcu lock when necessary, per Vlastimil]Show less |
In the Linux kernel, the following vulnerability has been resolved:
net/tcp: Disable TCP-AO static key after RCU grace period
The lifetime of TCP-AO static_key is the same as the last
tcp_ao_info. On the socket destruc...Show moreIn the Linux kernel, the following vulnerability has been resolved:
net/tcp: Disable TCP-AO static key after RCU grace period
The lifetime of TCP-AO static_key is the same as the last
tcp_ao_info. On the socket destruction tcp_ao_info ceases to be
with RCU grace period, while tcp-ao static branch is currently deferred
destructed. The static key definition is
: DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ);
which means that if RCU grace period is delayed by more than a second
and tcp_ao_needed is in the process of disablement, other CPUs may
yet see tcp_ao_info which atent dead, but soon-to-be.
And that breaks the assumption of static_key_fast_inc_not_disabled().
See the comment near the definition:
> * The caller must make sure that the static key can't get disabled while
> * in this function. It doesn't patch jump labels, only adds a user to
> * an already enabled static key.
Originally it was introduced in commit eb8c507296f6 ("jump_label:
Prevent key->enabled int overflow"), which is needed for the atomic
contexts, one of which would be the creation of a full socket from a
request socket. In that atomic context, it's known by the presence
of the key (md5/ao) that the static branch is already enabled.
So, the ref counter for that static branch is just incremented
instead of holding the proper mutex.
static_key_fast_inc_not_disabled() is just a helper for such usage
case. But it must not be used if the static branch could get disabled
in parallel as it's not protected by jump_label_mutex and as a result,
races with jump_label_update() implementation details.
Happened on netdev test-bot[1], so not a theoretical issue:
[] jump_label: Fatal kernel bug, unexpected op at tcp_inbound_hash+0x1a7/0x870 [ffffffffa8c4e9b7] (eb 50 0f 1f 44 != 66 90 0f 1f 00)) size:2 type:1
[] ------------[ cut here ]------------
[] kernel BUG at arch/x86/kernel/jump_label.c:73!
[] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
[] CPU: 3 PID: 243 Comm: kworker/3:3 Not tainted 6.10.0-virtme #1
[] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[] Workqueue: events jump_label_update_timeout
[] RIP: 0010:__jump_label_patch+0x2f6/0x350
...
[] Call Trace:
[] <TASK>
[] arch_jump_label_transform_queue+0x6c/0x110
[] __jump_label_update+0xef/0x350
[] __static_key_slow_dec_cpuslocked.part.0+0x3c/0x60
[] jump_label_update_timeout+0x2c/0x40
[] process_one_work+0xe3b/0x1670
[] worker_thread+0x587/0xce0
[] kthread+0x28a/0x350
[] ret_from_fork+0x31/0x70
[] ret_from_fork_asm+0x1a/0x30
[] </TASK>
[] Modules linked in: veth
[] ---[ end trace 0000000000000000 ]---
[] RIP: 0010:__jump_label_patch+0x2f6/0x350
[1]: https://netdev-3.bots.linux.dev/vmksft-tcp-ao-dbg/results/696681/5-connect-deny-ipv6/stderrShow less |
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add null check in resource_log_pipe_topology_update
[WHY]
When switching from "Extend" to "Second Display Only" we sometimes
call res...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add null check in resource_log_pipe_topology_update
[WHY]
When switching from "Extend" to "Second Display Only" we sometimes
call resource_get_otg_master_for_stream on a stream for the eDP,
which is disconnected. This leads to a null pointer dereference.
[HOW]
Added a null check in dc_resource.c/resource_log_pipe_topology_update.Show less |
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Add error handling to pair_device()
hci_conn_params_add() never checks for a NULL value and could lead to a NULL
pointer dereference...Show moreIn the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Add error handling to pair_device()
hci_conn_params_add() never checks for a NULL value and could lead to a NULL
pointer dereference causing a crash.
Fixed by adding error handling in the function.Show less |
In the Linux kernel, the following vulnerability has been resolved:
usb: vhci-hcd: Do not drop references before new references are gained
At a few places the driver carries stale pointers
to references that can still...Show moreIn the Linux kernel, the following vulnerability has been resolved:
usb: vhci-hcd: Do not drop references before new references are gained
At a few places the driver carries stale pointers
to references that can still be used. Make sure that does not happen.
This strictly speaking closes ZDI-CAN-22273, though there may be
similar races in the driver.Show less |
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: make apf token non-zero to fix bug
In current async pagefault logic, when a page is ready, KVM relies on
kvm_arch_can_dequeue_async_page...Show moreIn the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: make apf token non-zero to fix bug
In current async pagefault logic, when a page is ready, KVM relies on
kvm_arch_can_dequeue_async_page_present() to determine whether to deliver
a READY event to the Guest. This function test token value of struct
kvm_vcpu_pv_apf_data, which must be reset to zero by Guest kernel when a
READY event is finished by Guest. If value is zero meaning that a READY
event is done, so the KVM can deliver another.
But the kvm_arch_setup_async_pf() may produce a valid token with zero
value, which is confused with previous mention and may lead the loss of
this READY event.
This bug may cause task blocked forever in Guest:
INFO: task stress:7532 blocked for more than 1254 seconds.
Not tainted 5.10.0 #16
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:stress state:D stack: 0 pid: 7532 ppid: 1409
flags:0x00000080
Call Trace:
__schedule+0x1e7/0x650
schedule+0x46/0xb0
kvm_async_pf_task_wait_schedule+0xad/0xe0
? exit_to_user_mode_prepare+0x60/0x70
__kvm_handle_async_pf+0x4f/0xb0
? asm_exc_page_fault+0x8/0x30
exc_page_fault+0x6f/0x110
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x402d00
RSP: 002b:00007ffd31912500 EFLAGS: 00010206
RAX: 0000000000071000 RBX: ffffffffffffffff RCX: 00000000021a32b0
RDX: 000000000007d011 RSI: 000000000007d000 RDI: 00000000021262b0
RBP: 00000000021262b0 R08: 0000000000000003 R09: 0000000000000086
R10: 00000000000000eb R11: 00007fefbdf2baa0 R12: 0000000000000000
R13: 0000000000000002 R14: 000000000007d000 R15: 0000000000001000Show less |
In the Linux kernel, the following vulnerability has been resolved:
hwmon: Handle failure to register sensor with thermal zone correctly
If an attempt is made to a sensor with a thermal zone and it fails,
the call to d...Show moreIn the Linux kernel, the following vulnerability has been resolved:
hwmon: Handle failure to register sensor with thermal zone correctly
If an attempt is made to a sensor with a thermal zone and it fails,
the call to devm_thermal_zone_of_sensor_register() may return -ENODEV.
This may result in crashes similar to the following.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000003cd
...
Internal error: Oops: 96000021 [#1] PREEMPT SMP
...
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : mutex_lock+0x18/0x60
lr : thermal_zone_device_update+0x40/0x2e0
sp : ffff800014c4fc60
x29: ffff800014c4fc60 x28: ffff365ee3f6e000 x27: ffffdde218426790
x26: ffff365ee3f6e000 x25: 0000000000000000 x24: ffff365ee3f6e000
x23: ffffdde218426870 x22: ffff365ee3f6e000 x21: 00000000000003cd
x20: ffff365ee8bf3308 x19: ffffffffffffffed x18: 0000000000000000
x17: ffffdde21842689c x16: ffffdde1cb7a0b7c x15: 0000000000000040
x14: ffffdde21a4889a0 x13: 0000000000000228 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000001120000 x7 : 0000000000000001 x6 : 0000000000000000
x5 : 0068000878e20f07 x4 : 0000000000000000 x3 : 00000000000003cd
x2 : ffff365ee3f6e000 x1 : 0000000000000000 x0 : 00000000000003cd
Call trace:
mutex_lock+0x18/0x60
hwmon_notify_event+0xfc/0x110
0xffffdde1cb7a0a90
0xffffdde1cb7a0b7c
irq_thread_fn+0x2c/0xa0
irq_thread+0x134/0x240
kthread+0x178/0x190
ret_from_fork+0x10/0x20
Code: d503201f d503201f d2800001 aa0103e4 (c8e47c02)
Jon Hunter reports that the exact call sequence is:
hwmon_notify_event()
--> hwmon_thermal_notify()
--> thermal_zone_device_update()
--> update_temperature()
--> mutex_lock()
The hwmon core needs to handle all errors returned from calls
to devm_thermal_zone_of_sensor_register(). If the call fails
with -ENODEV, report that the sensor was not attached to a
thermal zone but continue to register the hwmon device.Show less |
In the Linux kernel, the following vulnerability has been resolved:
ice: fix concurrent reset and removal of VFs
Commit c503e63200c6 ("ice: Stop processing VF messages during teardown")
introduced a driver state flag,...Show moreIn the Linux kernel, the following vulnerability has been resolved:
ice: fix concurrent reset and removal of VFs
Commit c503e63200c6 ("ice: Stop processing VF messages during teardown")
introduced a driver state flag, ICE_VF_DEINIT_IN_PROGRESS, which is
intended to prevent some issues with concurrently handling messages from
VFs while tearing down the VFs.
This change was motivated by crashes caused while tearing down and
bringing up VFs in rapid succession.
It turns out that the fix actually introduces issues with the VF driver
caused because the PF no longer responds to any messages sent by the VF
during its .remove routine. This results in the VF potentially removing
its DMA memory before the PF has shut down the device queues.
Additionally, the fix doesn't actually resolve concurrency issues within
the ice driver. It is possible for a VF to initiate a reset just prior
to the ice driver removing VFs. This can result in the remove task
concurrently operating while the VF is being reset. This results in
similar memory corruption and panics purportedly fixed by that commit.
Fix this concurrency at its root by protecting both the reset and
removal flows using the existing VF cfg_lock. This ensures that we
cannot remove the VF while any outstanding critical tasks such as a
virtchnl message or a reset are occurring.
This locking change also fixes the root cause originally fixed by commit
c503e63200c6 ("ice: Stop processing VF messages during teardown"), so we
can simply revert it.
Note that I kept these two changes together because simply reverting the
original commit alone would leave the driver vulnerable to worse race
conditions.Show less |