| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ARM: 9317/1: kexec: Make smp stop calls asynchronous
If a panic is triggered by a hrtimer interrupt all online cpus will be
notified and set offline. But as highlighted by commit 19dbdcb8039c
("smp: Warn on function calls from softirq context") this call should
not be made synchronous with disabled interrupts:
softdog: Initiating panic
Kernel panic - not syncing: Software Watchdog Timer expired
WARNING: CPU: 1 PID: 0 at kernel/smp.c:753 smp_call_function_many_cond
unwind_backtrace:
show_stack
dump_stack_lvl
__warn
warn_slowpath_fmt
smp_call_function_many_cond
smp_call_function
crash_smp_send_stop.part.0
machine_crash_shutdown
__crash_kexec
panic
softdog_fire
__hrtimer_run_queues
hrtimer_interrupt
Make the smp call for machine_crash_nonpanic_core() asynchronous. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: cfg80211: Pass the PMK in binary instead of hex
Apparently the hex passphrase mechanism does not work on newer
chips/firmware (e.g. BCM4387). It seems there was a simple way of
passing it in binary all along, so use that and avoid the hexification.
OpenBSD has been doing it like this from the beginning, so this should
work on all chips.
Also clear the structure before setting the PMK. This was leaking
uninitialized stack contents to the device. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: disable sdma ecc irq only when sdma RAS is enabled in suspend
sdma_v4_0_ip is shared on a few asics, but in sdma_v4_0_hw_fini,
driver unconditionally disables ecc_irq which is only enabled on
those asics enabling sdma ecc. This will introduce a warning in
suspend cycle on those chips with sdma ip v4.0, while without
sdma ecc. So this patch correct this.
[ 7283.166354] RIP: 0010:amdgpu_irq_put+0x45/0x70 [amdgpu]
[ 7283.167001] RSP: 0018:ffff9a5fc3967d08 EFLAGS: 00010246
[ 7283.167019] RAX: ffff98d88afd3770 RBX: 0000000000000001 RCX: 0000000000000000
[ 7283.167023] RDX: 0000000000000000 RSI: ffff98d89da30390 RDI: ffff98d89da20000
[ 7283.167025] RBP: ffff98d89da20000 R08: 0000000000036838 R09: 0000000000000006
[ 7283.167028] R10: ffffd5764243c008 R11: 0000000000000000 R12: ffff98d89da30390
[ 7283.167030] R13: ffff98d89da38978 R14: ffffffff999ae15a R15: ffff98d880130105
[ 7283.167032] FS: 0000000000000000(0000) GS:ffff98d996f00000(0000) knlGS:0000000000000000
[ 7283.167036] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7283.167039] CR2: 00000000f7a9d178 CR3: 00000001c42ea000 CR4: 00000000003506e0
[ 7283.167041] Call Trace:
[ 7283.167046] <TASK>
[ 7283.167048] sdma_v4_0_hw_fini+0x38/0xa0 [amdgpu]
[ 7283.167704] amdgpu_device_ip_suspend_phase2+0x101/0x1a0 [amdgpu]
[ 7283.168296] amdgpu_device_suspend+0x103/0x180 [amdgpu]
[ 7283.168875] amdgpu_pmops_freeze+0x21/0x60 [amdgpu]
[ 7283.169464] pci_pm_freeze+0x54/0xc0 |
| In the Linux kernel, the following vulnerability has been resolved:
posix-timers: Ensure timer ID search-loop limit is valid
posix_timer_add() tries to allocate a posix timer ID by starting from the
cached ID which was stored by the last successful allocation.
This is done in a loop searching the ID space for a free slot one by
one. The loop has to terminate when the search wrapped around to the
starting point.
But that's racy vs. establishing the starting point. That is read out
lockless, which leads to the following problem:
CPU0 CPU1
posix_timer_add()
start = sig->posix_timer_id;
lock(hash_lock);
... posix_timer_add()
if (++sig->posix_timer_id < 0)
start = sig->posix_timer_id;
sig->posix_timer_id = 0;
So CPU1 can observe a negative start value, i.e. -1, and the loop break
never happens because the condition can never be true:
if (sig->posix_timer_id == start)
break;
While this is unlikely to ever turn into an endless loop as the ID space is
huge (INT_MAX), the racy read of the start value caught the attention of
KCSAN and Dmitry unearthed that incorrectness.
Rewrite it so that all id operations are under the hash lock. |
| In the Linux kernel, the following vulnerability has been resolved:
quota: fix warning in dqgrab()
There's issue as follows when do fault injection:
WARNING: CPU: 1 PID: 14870 at include/linux/quotaops.h:51 dquot_disable+0x13b7/0x18c0
Modules linked in:
CPU: 1 PID: 14870 Comm: fsconfig Not tainted 6.3.0-next-20230505-00006-g5107a9c821af-dirty #541
RIP: 0010:dquot_disable+0x13b7/0x18c0
RSP: 0018:ffffc9000acc79e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88825e41b980
RDX: 0000000000000000 RSI: ffff88825e41b980 RDI: 0000000000000002
RBP: ffff888179f68000 R08: ffffffff82087ca7 R09: 0000000000000000
R10: 0000000000000001 R11: ffffed102f3ed026 R12: ffff888179f68130
R13: ffff888179f68110 R14: dffffc0000000000 R15: ffff888179f68118
FS: 00007f450a073740(0000) GS:ffff88882fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe96f2efd8 CR3: 000000025c8ad000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
dquot_load_quota_sb+0xd53/0x1060
dquot_resume+0x172/0x230
ext4_reconfigure+0x1dc6/0x27b0
reconfigure_super+0x515/0xa90
__x64_sys_fsconfig+0xb19/0xd20
do_syscall_64+0x39/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Above issue may happens as follows:
ProcessA ProcessB ProcessC
sys_fsconfig
vfs_fsconfig_locked
reconfigure_super
ext4_remount
dquot_suspend -> suspend all type quota
sys_fsconfig
vfs_fsconfig_locked
reconfigure_super
ext4_remount
dquot_resume
ret = dquot_load_quota_sb
add_dquot_ref
do_open -> open file O_RDWR
vfs_open
do_dentry_open
get_write_access
atomic_inc_unless_negative(&inode->i_writecount)
ext4_file_open
dquot_file_open
dquot_initialize
__dquot_initialize
dqget
atomic_inc(&dquot->dq_count);
__dquot_initialize
__dquot_initialize
dqget
if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
ext4_acquire_dquot
-> Return error DQ_ACTIVE_B flag isn't set
dquot_disable
invalidate_dquots
if (atomic_read(&dquot->dq_count))
dqgrab
WARN_ON_ONCE(!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
-> Trigger warning
In the above scenario, 'dquot->dq_flags' has no DQ_ACTIVE_B is normal when
dqgrab().
To solve above issue just replace the dqgrab() use in invalidate_dquots() with
atomic_inc(&dquot->dq_count). |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Array index may go out of bound
Klocwork reports array 'vha->host_str' of size 16 may use index value(s)
16..19. Use snprintf() instead of sprintf(). |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix issue in verifying allow_ptr_leaks
After we converted the capabilities of our networking-bpf program from
cap_sys_admin to cap_net_admin+cap_bpf, our networking-bpf program
failed to start. Because it failed the bpf verifier, and the error log
is "R3 pointer comparison prohibited".
A simple reproducer as follows,
SEC("cls-ingress")
int ingress(struct __sk_buff *skb)
{
struct iphdr *iph = (void *)(long)skb->data + sizeof(struct ethhdr);
if ((long)(iph + 1) > (long)skb->data_end)
return TC_ACT_STOLEN;
return TC_ACT_OK;
}
Per discussion with Yonghong and Alexei [1], comparison of two packet
pointers is not a pointer leak. This patch fixes it.
Our local kernel is 6.1.y and we expect this fix to be backported to
6.1.y, so stable is CCed.
[1]. https://lore.kernel.org/bpf/CAADnVQ+Nmspr7Si+pxWn8zkE7hX-7s93ugwC+94aXSy4uQ9vBg@mail.gmail.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/adreno: Fix null ptr access in adreno_gpu_cleanup()
Fix the below kernel panic due to null pointer access:
[ 18.504431] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000048
[ 18.513464] Mem abort info:
[ 18.516346] ESR = 0x0000000096000005
[ 18.520204] EC = 0x25: DABT (current EL), IL = 32 bits
[ 18.525706] SET = 0, FnV = 0
[ 18.528878] EA = 0, S1PTW = 0
[ 18.532117] FSC = 0x05: level 1 translation fault
[ 18.537138] Data abort info:
[ 18.540110] ISV = 0, ISS = 0x00000005
[ 18.544060] CM = 0, WnR = 0
[ 18.547109] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000112826000
[ 18.553738] [0000000000000048] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[ 18.562690] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
**Snip**
[ 18.696758] Call trace:
[ 18.699278] adreno_gpu_cleanup+0x30/0x88
[ 18.703396] a6xx_destroy+0xc0/0x130
[ 18.707066] a6xx_gpu_init+0x308/0x424
[ 18.710921] adreno_bind+0x178/0x288
[ 18.714590] component_bind_all+0xe0/0x214
[ 18.718797] msm_drm_bind+0x1d4/0x614
[ 18.722566] try_to_bring_up_aggregate_device+0x16c/0x1b8
[ 18.728105] __component_add+0xa0/0x158
[ 18.732048] component_add+0x20/0x2c
[ 18.735719] adreno_probe+0x40/0xc0
[ 18.739300] platform_probe+0xb4/0xd4
[ 18.743068] really_probe+0xfc/0x284
[ 18.746738] __driver_probe_device+0xc0/0xec
[ 18.751129] driver_probe_device+0x48/0x110
[ 18.755421] __device_attach_driver+0xa8/0xd0
[ 18.759900] bus_for_each_drv+0x90/0xdc
[ 18.763843] __device_attach+0xfc/0x174
[ 18.767786] device_initial_probe+0x20/0x2c
[ 18.772090] bus_probe_device+0x40/0xa0
[ 18.776032] deferred_probe_work_func+0x94/0xd0
[ 18.780686] process_one_work+0x190/0x3d0
[ 18.784805] worker_thread+0x280/0x3d4
[ 18.788659] kthread+0x104/0x1c0
[ 18.791981] ret_from_fork+0x10/0x20
[ 18.795654] Code: f9400408 aa0003f3 aa1f03f4 91142015 (f9402516)
[ 18.801913] ---[ end trace 0000000000000000 ]---
[ 18.809039] Kernel panic - not syncing: Oops: Fatal exception
Patchwork: https://patchwork.freedesktop.org/patch/515605/ |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: sunplus: fix return value check of mmc_add_host()
mmc_add_host() may return error, if we ignore its return value,
1. the memory allocated in mmc_alloc_host() will be leaked
2. null-ptr-deref will happen when calling mmc_remove_host()
in remove function spmmc_drv_remove() because deleting not
added device.
Fix this by checking the return value of mmc_add_host(). Moreover,
I fixed the error handling path of spmmc_drv_probe() to clean up. |
| In the Linux kernel, the following vulnerability has been resolved:
media: ov5675: Fix memleak in ov5675_init_controls()
There is a kmemleak when testing the media/i2c/ov5675.c with bpf mock
device:
AssertionError: unreferenced object 0xffff888107362160 (size 16):
comm "python3", pid 277, jiffies 4294832798 (age 20.722s)
hex dump (first 16 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000abe7d67c>] __kmalloc_node+0x44/0x1b0
[<000000008a725aac>] kvmalloc_node+0x34/0x180
[<000000009a53cd11>] v4l2_ctrl_handler_init_class+0x11d/0x180
[videodev]
[<0000000055b46db0>] ov5675_probe+0x38b/0x897 [ov5675]
[<00000000153d886c>] i2c_device_probe+0x28d/0x680
[<000000004afb7e8f>] really_probe+0x17c/0x3f0
[<00000000ff2f18e4>] __driver_probe_device+0xe3/0x170
[<000000000a001029>] driver_probe_device+0x49/0x120
[<00000000e39743c7>] __device_attach_driver+0xf7/0x150
[<00000000d32fd070>] bus_for_each_drv+0x114/0x180
[<000000009083ac41>] __device_attach+0x1e5/0x2d0
[<0000000015b4a830>] bus_probe_device+0x126/0x140
[<000000007813deaf>] device_add+0x810/0x1130
[<000000007becb867>] i2c_new_client_device+0x386/0x540
[<000000007f9cf4b4>] of_i2c_register_device+0xf1/0x110
[<00000000ebfdd032>] of_i2c_notify+0xfc/0x1f0
ov5675_init_controls() won't clean all the allocated resources in fail
path, which may causes the memleaks. Add v4l2_ctrl_handler_free() to
prevent memleak. |
| In the Linux kernel, the following vulnerability has been resolved:
block: fix blktrace debugfs entries leakage
Commit 99d055b4fd4b ("block: remove per-disk debugfs files in
blk_unregister_queue") moves blk_trace_shutdown() from
blk_release_queue() to blk_unregister_queue(), this is safe if blktrace
is created through sysfs, however, there is a regression in corner
case.
blktrace can still be enabled after del_gendisk() through ioctl if
the disk is opened before del_gendisk(), and if blktrace is not shutdown
through ioctl before closing the disk, debugfs entries will be leaked.
Fix this problem by shutdown blktrace in disk_release(), this is safe
because blk_trace_remove() is reentrant. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: sisusbvga: Add endpoint checks
The syzbot fuzzer was able to provoke a WARNING from the sisusbvga driver:
------------[ cut here ]------------
usb 1-1: BOGUS urb xfer, pipe 3 != type 1
WARNING: CPU: 1 PID: 26 at drivers/usb/core/urb.c:504 usb_submit_urb+0xed6/0x1880 drivers/usb/core/urb.c:504
Modules linked in:
CPU: 1 PID: 26 Comm: kworker/1:1 Not tainted 6.2.0-rc5-syzkaller-00199-g5af6ce704936 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Workqueue: usb_hub_wq hub_event
RIP: 0010:usb_submit_urb+0xed6/0x1880 drivers/usb/core/urb.c:504
Code: 7c 24 18 e8 6c 50 80 fb 48 8b 7c 24 18 e8 62 1a 01 ff 41 89 d8 44 89 e1 4c 89 ea 48 89 c6 48 c7 c7 60 b1 fa 8a e8 84 b0 be 03 <0f> 0b e9 58 f8 ff ff e8 3e 50 80 fb 48 81 c5 c0 05 00 00 e9 84 f7
RSP: 0018:ffffc90000a1ed18 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff888012783a80 RSI: ffffffff816680ec RDI: fffff52000143d95
RBP: ffff888079020000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000000 R12: 0000000000000003
R13: ffff888017d33370 R14: 0000000000000003 R15: ffff888021213600
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005592753a60b0 CR3: 0000000022899000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
sisusb_bulkout_msg drivers/usb/misc/sisusbvga/sisusbvga.c:224 [inline]
sisusb_send_bulk_msg.constprop.0+0x904/0x1230 drivers/usb/misc/sisusbvga/sisusbvga.c:379
sisusb_send_bridge_packet drivers/usb/misc/sisusbvga/sisusbvga.c:567 [inline]
sisusb_do_init_gfxdevice drivers/usb/misc/sisusbvga/sisusbvga.c:2077 [inline]
sisusb_init_gfxdevice+0x87b/0x4000 drivers/usb/misc/sisusbvga/sisusbvga.c:2177
sisusb_probe+0x9cd/0xbe2 drivers/usb/misc/sisusbvga/sisusbvga.c:2869
...
The problem was caused by the fact that the driver does not check
whether the endpoints it uses are actually present and have the
appropriate types. This can be fixed by adding a simple check of
the endpoints. |
| In the Linux kernel, the following vulnerability has been resolved:
virtio-vdpa: Fix cpumask memory leak in virtio_vdpa_find_vqs()
Free the cpumask allocated by create_affinity_masks() before returning
from the function. |
| In the Linux kernel, the following vulnerability has been resolved:
clk: imx93: fix memory leak and missing unwind goto in imx93_clocks_probe
In function probe(), it returns directly without unregistered hws
when error occurs.
Fix this by adding 'goto unregister_hws;' on line 295 and
line 310.
Use devm_kzalloc() instead of kzalloc() to automatically
free the memory using devm_kfree() when error occurs.
Replace of_iomap() with devm_of_iomap() to automatically
handle the unused ioremap region and delete 'iounmap(anatop_base);'
in unregister_hws. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ipa: only reset hashed tables when supported
Last year, the code that manages GSI channel transactions switched
from using spinlock-protected linked lists to using indexes into the
ring buffer used for a channel. Recently, Google reported seeing
transaction reference count underflows occasionally during shutdown.
Doug Anderson found a way to reproduce the issue reliably, and
bisected the issue to the commit that eliminated the linked lists
and the lock. The root cause was ultimately determined to be
related to unused transactions being committed as part of the modem
shutdown cleanup activity. Unused transactions are not normally
expected (except in error cases).
The modem uses some ranges of IPA-resident memory, and whenever it
shuts down we zero those ranges. In ipa_filter_reset_table() a
transaction is allocated to zero modem filter table entries. If
hashing is not supported, hashed table memory should not be zeroed.
But currently nothing prevents that, and the result is an unused
transaction. Something similar occurs when we zero routing table
entries for the modem.
By preventing any attempt to clear hashed tables when hashing is not
supported, the reference count underflow is avoided in this case.
Note that there likely remains an issue with properly freeing unused
transactions (if they occur due to errors). This patch addresses
only the underflows that Google originally reported. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: asix: hold PM usage ref to avoid PM/MDIO + RTNL deadlock
Prevent USB runtime PM (autosuspend) for AX88772* in bind.
usbnet enables runtime PM (autosuspend) by default, so disabling it via
the usb_driver flag is ineffective. On AX88772B, autosuspend shows no
measurable power saving with current driver (no link partner, admin
up/down). The ~0.453 W -> ~0.248 W drop on v6.1 comes from phylib powering
the PHY off on admin-down, not from USB autosuspend.
The real hazard is that with runtime PM enabled, ndo_open() (under RTNL)
may synchronously trigger autoresume (usb_autopm_get_interface()) into
asix_resume() while the USB PM lock is held. Resume paths then invoke
phylink/phylib and MDIO, which also expect RTNL, leading to possible
deadlocks or PM lock vs MDIO wake issues.
To avoid this, keep the device runtime-PM active by taking a usage
reference in ax88772_bind() and dropping it in unbind(). A non-zero PM
usage count blocks runtime suspend regardless of userspace policy
(.../power/control - pm_runtime_allow/forbid), making this approach
robust against sysfs overrides.
Holding a runtime-PM usage ref does not affect system-wide suspend;
system sleep/resume callbacks continue to run as before. |
| In the Linux kernel, the following vulnerability has been resolved:
arch_topology: Fix incorrect error check in topology_parse_cpu_capacity()
Fix incorrect use of PTR_ERR_OR_ZERO() in topology_parse_cpu_capacity()
which causes the code to proceed with NULL clock pointers. The current
logic uses !PTR_ERR_OR_ZERO(cpu_clk) which evaluates to true for both
valid pointers and NULL, leading to potential NULL pointer dereference
in clk_get_rate().
Per include/linux/err.h documentation, PTR_ERR_OR_ZERO(ptr) returns:
"The error code within @ptr if it is an error pointer; 0 otherwise."
This means PTR_ERR_OR_ZERO() returns 0 for both valid pointers AND NULL
pointers. Therefore !PTR_ERR_OR_ZERO(cpu_clk) evaluates to true (proceed)
when cpu_clk is either valid or NULL, causing clk_get_rate(NULL) to be
called when of_clk_get() returns NULL.
Replace with !IS_ERR_OR_NULL(cpu_clk) which only proceeds for valid
pointers, preventing potential NULL pointer dereference in clk_get_rate(). |
| In the Linux kernel, the following vulnerability has been resolved:
platform/mellanox: mlxbf-pmc: add sysfs_attr_init() to count_clock init
The lock-related debug logic (CONFIG_LOCK_STAT) in the kernel is noting
the following warning when the BlueField-3 SOC is booted:
BUG: key ffff00008a3402a8 has not been registered!
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 4 PID: 592 at kernel/locking/lockdep.c:4801 lockdep_init_map_type+0x1d4/0x2a0
<snip>
Call trace:
lockdep_init_map_type+0x1d4/0x2a0
__kernfs_create_file+0x84/0x140
sysfs_add_file_mode_ns+0xcc/0x1cc
internal_create_group+0x110/0x3d4
internal_create_groups.part.0+0x54/0xcc
sysfs_create_groups+0x24/0x40
device_add+0x6e8/0x93c
device_register+0x28/0x40
__hwmon_device_register+0x4b0/0x8a0
devm_hwmon_device_register_with_groups+0x7c/0xe0
mlxbf_pmc_probe+0x1e8/0x3e0 [mlxbf_pmc]
platform_probe+0x70/0x110
The mlxbf_pmc driver must call sysfs_attr_init() during the
initialization of the "count_clock" data structure to avoid
this warning. |
| In the Linux kernel, the following vulnerability has been resolved:
sysfs: check visibility before changing group attribute ownership
Since commit 0c17270f9b92 ("net: sysfs: Implement is_visible for
phys_(port_id, port_name, switch_id)"), __dev_change_net_namespace() can
hit WARN_ON() when trying to change owner of a file that isn't visible.
See the trace below:
WARNING: CPU: 6 PID: 2938 at net/core/dev.c:12410 __dev_change_net_namespace+0xb89/0xc30
CPU: 6 UID: 0 PID: 2938 Comm: incusd Not tainted 6.17.1-1-mainline #1 PREEMPT(full) 4b783b4a638669fb644857f484487d17cb45ed1f
Hardware name: Framework Laptop 13 (AMD Ryzen 7040Series)/FRANMDCP07, BIOS 03.07 02/19/2025
RIP: 0010:__dev_change_net_namespace+0xb89/0xc30
[...]
Call Trace:
<TASK>
? if6_seq_show+0x30/0x50
do_setlink.isra.0+0xc7/0x1270
? __nla_validate_parse+0x5c/0xcc0
? security_capable+0x94/0x1a0
rtnl_newlink+0x858/0xc20
? update_curr+0x8e/0x1c0
? update_entity_lag+0x71/0x80
? sched_balance_newidle+0x358/0x450
? psi_task_switch+0x113/0x2a0
? __pfx_rtnl_newlink+0x10/0x10
rtnetlink_rcv_msg+0x346/0x3e0
? sched_clock+0x10/0x30
? __pfx_rtnetlink_rcv_msg+0x10/0x10
netlink_rcv_skb+0x59/0x110
netlink_unicast+0x285/0x3c0
? __alloc_skb+0xdb/0x1a0
netlink_sendmsg+0x20d/0x430
____sys_sendmsg+0x39f/0x3d0
? import_iovec+0x2f/0x40
___sys_sendmsg+0x99/0xe0
__sys_sendmsg+0x8a/0xf0
do_syscall_64+0x81/0x970
? __sys_bind+0xe3/0x110
? syscall_exit_work+0x143/0x1b0
? do_syscall_64+0x244/0x970
? sock_alloc_file+0x63/0xc0
? syscall_exit_work+0x143/0x1b0
? do_syscall_64+0x244/0x970
? alloc_fd+0x12e/0x190
? put_unused_fd+0x2a/0x70
? do_sys_openat2+0xa2/0xe0
? syscall_exit_work+0x143/0x1b0
? do_syscall_64+0x244/0x970
? exc_page_fault+0x7e/0x1a0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
[...]
</TASK>
Fix this by checking is_visible() before trying to touch the attribute. |
| In the Linux kernel, the following vulnerability has been resolved:
netpoll: Fix deadlock in memory allocation under spinlock
Fix a AA deadlock in refill_skbs() where memory allocation while holding
skb_pool->lock can trigger a recursive lock acquisition attempt.
The deadlock scenario occurs when the system is under severe memory
pressure:
1. refill_skbs() acquires skb_pool->lock (spinlock)
2. alloc_skb() is called while holding the lock
3. Memory allocator fails and calls slab_out_of_memory()
4. This triggers printk() for the OOM warning
5. The console output path calls netpoll_send_udp()
6. netpoll_send_udp() attempts to acquire the same skb_pool->lock
7. Deadlock: the lock is already held by the same CPU
Call stack:
refill_skbs()
spin_lock_irqsave(&skb_pool->lock) <- lock acquired
__alloc_skb()
kmem_cache_alloc_node_noprof()
slab_out_of_memory()
printk()
console_flush_all()
netpoll_send_udp()
skb_dequeue()
spin_lock_irqsave(&skb_pool->lock) <- deadlock attempt
This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb
refilling on critical path") which removed refill_skbs() from the
critical path (where nested printk was being deferred), letting nested
printk being called from inside refill_skbs()
Refactor refill_skbs() to never allocate memory while holding
the spinlock.
Another possible solution to fix this problem is protecting the
refill_skbs() from nested printks, basically calling
printk_deferred_{enter,exit}() in refill_skbs(), then, any nested
pr_warn() would be deferred.
I prefer this approach, given I _think_ it might be a good idea to move
the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having
the alloc_skb() outside of the lock will be necessary step.
There is a possible TOCTOU issue when checking for the pool length, and
queueing the new allocated skb, but, this is not an issue, given that
an extra SKB in the pool is harmless and it will be eventually used. |
