| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
sysv: don't call sb_bread() with pointers_lock held
syzbot is reporting sleep in atomic context in SysV filesystem [1], for
sb_bread() is called with rw_spinlock held.
A "write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock" bug
and a "sb_bread() with write_lock(&pointers_lock)" bug were introduced by
"Replace BKL for chain locking with sysvfs-private rwlock" in Linux 2.5.12.
Then, "[PATCH] err1-40: sysvfs locking fix" in Linux 2.6.8 fixed the
former bug by moving pointers_lock lock to the callers, but instead
introduced a "sb_bread() with read_lock(&pointers_lock)" bug (which made
this problem easier to hit).
Al Viro suggested that why not to do like get_branch()/get_block()/
find_shared() in Minix filesystem does. And doing like that is almost a
revert of "[PATCH] err1-40: sysvfs locking fix" except that get_branch()
from with find_shared() is called without write_lock(&pointers_lock). |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/powernv: Add a null pointer check in opal_powercap_init()
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: fix a double-free in si_dpm_init
When the allocation of
adev->pm.dpm.dyn_state.vddc_dependency_on_dispclk.entries fails,
amdgpu_free_extended_power_table is called to free some fields of adev.
However, when the control flow returns to si_dpm_sw_init, it goes to
label dpm_failed and calls si_dpm_fini, which calls
amdgpu_free_extended_power_table again and free those fields again. Thus
a double-free is triggered. |
| In the Linux kernel, the following vulnerability has been resolved:
of: Fix double free in of_parse_phandle_with_args_map
In of_parse_phandle_with_args_map() the inner loop that
iterates through the map entries calls of_node_put(new)
to free the reference acquired by the previous iteration
of the inner loop. This assumes that the value of "new" is
NULL on the first iteration of the inner loop.
Make sure that this is true in all iterations of the outer
loop by setting "new" to NULL after its value is assigned to "cur".
Extend the unittest to detect the double free and add an additional
test case that actually triggers this path. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/tegra: dsi: Add missing check for of_find_device_by_node
Add check for the return value of of_find_device_by_node() and return
the error if it fails in order to avoid NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: b43: Stop/wake correct queue in DMA Tx path when QoS is disabled
When QoS is disabled, the queue priority value will not map to the correct
ieee80211 queue since there is only one queue. Stop/wake queue 0 when QoS
is disabled to prevent trying to stop/wake a non-existent queue and failing
to stop/wake the actual queue instantiated.
Log of issue before change (with kernel parameter qos=0):
[ +5.112651] ------------[ cut here ]------------
[ +0.000005] WARNING: CPU: 7 PID: 25513 at net/mac80211/util.c:449 __ieee80211_wake_queue+0xd5/0x180 [mac80211]
[ +0.000067] Modules linked in: b43(O) snd_seq_dummy snd_hrtimer snd_seq snd_seq_device nft_chain_nat xt_MASQUERADE nf_nat xfrm_user xfrm_algo xt_addrtype overlay ccm af_packet amdgpu snd_hda_codec_cirrus snd_hda_codec_generic ledtrig_audio drm_exec amdxcp gpu_sched xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_rpfilter ipt_rpfilter xt_pkttype xt_LOG nf_log_syslog xt_tcpudp nft_compat nf_tables nfnetlink sch_fq_codel btusb uinput iTCO_wdt ctr btrtl intel_pmc_bxt i915 intel_rapl_msr mei_hdcp mei_pxp joydev at24 watchdog btintel atkbd libps2 serio radeon btbcm vivaldi_fmap btmtk intel_rapl_common snd_hda_codec_hdmi bluetooth uvcvideo nls_iso8859_1 applesmc nls_cp437 x86_pkg_temp_thermal snd_hda_intel intel_powerclamp vfat videobuf2_vmalloc coretemp fat snd_intel_dspcfg crc32_pclmul uvc polyval_clmulni snd_intel_sdw_acpi loop videobuf2_memops snd_hda_codec tun drm_suballoc_helper polyval_generic drm_ttm_helper drm_buddy tap ecdh_generic videobuf2_v4l2 gf128mul macvlan ttm ghash_clmulni_intel ecc tg3
[ +0.000044] videodev bridge snd_hda_core rapl crc16 drm_display_helper cec mousedev snd_hwdep evdev intel_cstate bcm5974 hid_appleir videobuf2_common stp mac_hid libphy snd_pcm drm_kms_helper acpi_als mei_me intel_uncore llc mc snd_timer intel_gtt industrialio_triggered_buffer apple_mfi_fastcharge i2c_i801 mei snd lpc_ich agpgart ptp i2c_smbus thunderbolt apple_gmux i2c_algo_bit kfifo_buf video industrialio soundcore pps_core wmi tiny_power_button sbs sbshc button ac cordic bcma mac80211 cfg80211 ssb rfkill libarc4 kvm_intel kvm drm irqbypass fuse backlight firmware_class efi_pstore configfs efivarfs dmi_sysfs ip_tables x_tables autofs4 dm_crypt cbc encrypted_keys trusted asn1_encoder tee tpm rng_core input_leds hid_apple led_class hid_generic usbhid hid sd_mod t10_pi crc64_rocksoft crc64 crc_t10dif crct10dif_generic ahci libahci libata uhci_hcd ehci_pci ehci_hcd crct10dif_pclmul crct10dif_common sha512_ssse3 sha512_generic sha256_ssse3 sha1_ssse3 aesni_intel usbcore scsi_mod libaes crypto_simd cryptd scsi_common
[ +0.000055] usb_common rtc_cmos btrfs blake2b_generic libcrc32c crc32c_generic crc32c_intel xor raid6_pq dm_snapshot dm_bufio dm_mod dax [last unloaded: b43(O)]
[ +0.000009] CPU: 7 PID: 25513 Comm: irq/17-b43 Tainted: G W O 6.6.7 #1-NixOS
[ +0.000003] Hardware name: Apple Inc. MacBookPro8,3/Mac-942459F5819B171B, BIOS 87.0.0.0.0 06/13/2019
[ +0.000001] RIP: 0010:__ieee80211_wake_queue+0xd5/0x180 [mac80211]
[ +0.000046] Code: 00 45 85 e4 0f 85 9b 00 00 00 48 8d bd 40 09 00 00 f0 48 0f ba ad 48 09 00 00 00 72 0f 5b 5d 41 5c 41 5d 41 5e e9 cb 6d 3c d0 <0f> 0b 5b 5d 41 5c 41 5d 41 5e c3 cc cc cc cc 48 8d b4 16 94 00 00
[ +0.000002] RSP: 0018:ffffc90003c77d60 EFLAGS: 00010097
[ +0.000001] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 0000000000000000
[ +0.000001] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff88820b924900
[ +0.000002] RBP: ffff88820b924900 R08: ffffc90003c77d90 R09: 000000000003bfd0
[ +0.000001] R10: ffff88820b924900 R11: ffffc90003c77c68 R12: 0000000000000000
[ +0.000001] R13: 0000000000000000 R14: ffffc90003c77d90 R15: ffffffffc0fa6f40
[ +0.000001] FS: 0000000000000000(0000) GS:ffff88846fb80000(0000) knlGS:0000000000000000
[ +0.000001] CS: 0010 DS: 0
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
media: rc: bpf attach/detach requires write permission
Note that bpf attach/detach also requires CAP_NET_ADMIN. |
| In the Linux kernel, the following vulnerability has been resolved:
can: j1939: Fix UAF in j1939_sk_match_filter during setsockopt(SO_J1939_FILTER)
Lock jsk->sk to prevent UAF when setsockopt(..., SO_J1939_FILTER, ...)
modifies jsk->filters while receiving packets.
Following trace was seen on affected system:
==================================================================
BUG: KASAN: slab-use-after-free in j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
Read of size 4 at addr ffff888012144014 by task j1939/350
CPU: 0 PID: 350 Comm: j1939 Tainted: G W OE 6.5.0-rc5 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
print_report+0xd3/0x620
? kasan_complete_mode_report_info+0x7d/0x200
? j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
kasan_report+0xc2/0x100
? j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
__asan_load4+0x84/0xb0
j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
j1939_sk_recv+0x20b/0x320 [can_j1939]
? __kasan_check_write+0x18/0x20
? __pfx_j1939_sk_recv+0x10/0x10 [can_j1939]
? j1939_simple_recv+0x69/0x280 [can_j1939]
? j1939_ac_recv+0x5e/0x310 [can_j1939]
j1939_can_recv+0x43f/0x580 [can_j1939]
? __pfx_j1939_can_recv+0x10/0x10 [can_j1939]
? raw_rcv+0x42/0x3c0 [can_raw]
? __pfx_j1939_can_recv+0x10/0x10 [can_j1939]
can_rcv_filter+0x11f/0x350 [can]
can_receive+0x12f/0x190 [can]
? __pfx_can_rcv+0x10/0x10 [can]
can_rcv+0xdd/0x130 [can]
? __pfx_can_rcv+0x10/0x10 [can]
__netif_receive_skb_one_core+0x13d/0x150
? __pfx___netif_receive_skb_one_core+0x10/0x10
? __kasan_check_write+0x18/0x20
? _raw_spin_lock_irq+0x8c/0xe0
__netif_receive_skb+0x23/0xb0
process_backlog+0x107/0x260
__napi_poll+0x69/0x310
net_rx_action+0x2a1/0x580
? __pfx_net_rx_action+0x10/0x10
? __pfx__raw_spin_lock+0x10/0x10
? handle_irq_event+0x7d/0xa0
__do_softirq+0xf3/0x3f8
do_softirq+0x53/0x80
</IRQ>
<TASK>
__local_bh_enable_ip+0x6e/0x70
netif_rx+0x16b/0x180
can_send+0x32b/0x520 [can]
? __pfx_can_send+0x10/0x10 [can]
? __check_object_size+0x299/0x410
raw_sendmsg+0x572/0x6d0 [can_raw]
? __pfx_raw_sendmsg+0x10/0x10 [can_raw]
? apparmor_socket_sendmsg+0x2f/0x40
? __pfx_raw_sendmsg+0x10/0x10 [can_raw]
sock_sendmsg+0xef/0x100
sock_write_iter+0x162/0x220
? __pfx_sock_write_iter+0x10/0x10
? __rtnl_unlock+0x47/0x80
? security_file_permission+0x54/0x320
vfs_write+0x6ba/0x750
? __pfx_vfs_write+0x10/0x10
? __fget_light+0x1ca/0x1f0
? __rcu_read_unlock+0x5b/0x280
ksys_write+0x143/0x170
? __pfx_ksys_write+0x10/0x10
? __kasan_check_read+0x15/0x20
? fpregs_assert_state_consistent+0x62/0x70
__x64_sys_write+0x47/0x60
do_syscall_64+0x60/0x90
? do_syscall_64+0x6d/0x90
? irqentry_exit+0x3f/0x50
? exc_page_fault+0x79/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Allocated by task 348:
kasan_save_stack+0x2a/0x50
kasan_set_track+0x29/0x40
kasan_save_alloc_info+0x1f/0x30
__kasan_kmalloc+0xb5/0xc0
__kmalloc_node_track_caller+0x67/0x160
j1939_sk_setsockopt+0x284/0x450 [can_j1939]
__sys_setsockopt+0x15c/0x2f0
__x64_sys_setsockopt+0x6b/0x80
do_syscall_64+0x60/0x90
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Freed by task 349:
kasan_save_stack+0x2a/0x50
kasan_set_track+0x29/0x40
kasan_save_free_info+0x2f/0x50
__kasan_slab_free+0x12e/0x1c0
__kmem_cache_free+0x1b9/0x380
kfree+0x7a/0x120
j1939_sk_setsockopt+0x3b2/0x450 [can_j1939]
__sys_setsockopt+0x15c/0x2f0
__x64_sys_setsockopt+0x6b/0x80
do_syscall_64+0x60/0x90
entry_SYSCALL_64_after_hwframe+0x6e/0xd8 |
| In the Linux kernel, the following vulnerability has been resolved:
PM / devfreq: Synchronize devfreq_monitor_[start/stop]
There is a chance if a frequent switch of the governor
done in a loop result in timer list corruption where
timer cancel being done from two place one from
cancel_delayed_work_sync() and followed by expire_timers()
can be seen from the traces[1].
while true
do
echo "simple_ondemand" > /sys/class/devfreq/1d84000.ufshc/governor
echo "performance" > /sys/class/devfreq/1d84000.ufshc/governor
done
It looks to be issue with devfreq driver where
device_monitor_[start/stop] need to synchronized so that
delayed work should get corrupted while it is either
being queued or running or being cancelled.
Let's use polling flag and devfreq lock to synchronize the
queueing the timer instance twice and work data being
corrupted.
[1]
...
..
<idle>-0 [003] 9436.209662: timer_cancel timer=0xffffff80444f0428
<idle>-0 [003] 9436.209664: timer_expire_entry timer=0xffffff80444f0428 now=0x10022da1c function=__typeid__ZTSFvP10timer_listE_global_addr baseclk=0x10022da1c
<idle>-0 [003] 9436.209718: timer_expire_exit timer=0xffffff80444f0428
kworker/u16:6-14217 [003] 9436.209863: timer_start timer=0xffffff80444f0428 function=__typeid__ZTSFvP10timer_listE_global_addr expires=0x10022da2b now=0x10022da1c flags=182452227
vendor.xxxyyy.ha-1593 [004] 9436.209888: timer_cancel timer=0xffffff80444f0428
vendor.xxxyyy.ha-1593 [004] 9436.216390: timer_init timer=0xffffff80444f0428
vendor.xxxyyy.ha-1593 [004] 9436.216392: timer_start timer=0xffffff80444f0428 function=__typeid__ZTSFvP10timer_listE_global_addr expires=0x10022da2c now=0x10022da1d flags=186646532
vendor.xxxyyy.ha-1593 [005] 9436.220992: timer_cancel timer=0xffffff80444f0428
xxxyyyTraceManag-7795 [004] 9436.261641: timer_cancel timer=0xffffff80444f0428
[2]
9436.261653][ C4] Unable to handle kernel paging request at virtual address dead00000000012a
[ 9436.261664][ C4] Mem abort info:
[ 9436.261666][ C4] ESR = 0x96000044
[ 9436.261669][ C4] EC = 0x25: DABT (current EL), IL = 32 bits
[ 9436.261671][ C4] SET = 0, FnV = 0
[ 9436.261673][ C4] EA = 0, S1PTW = 0
[ 9436.261675][ C4] Data abort info:
[ 9436.261677][ C4] ISV = 0, ISS = 0x00000044
[ 9436.261680][ C4] CM = 0, WnR = 1
[ 9436.261682][ C4] [dead00000000012a] address between user and kernel address ranges
[ 9436.261685][ C4] Internal error: Oops: 96000044 [#1] PREEMPT SMP
[ 9436.261701][ C4] Skip md ftrace buffer dump for: 0x3a982d0
...
[ 9436.262138][ C4] CPU: 4 PID: 7795 Comm: TraceManag Tainted: G S W O 5.10.149-android12-9-o-g17f915d29d0c #1
[ 9436.262141][ C4] Hardware name: Qualcomm Technologies, Inc. (DT)
[ 9436.262144][ C4] pstate: 22400085 (nzCv daIf +PAN -UAO +TCO BTYPE=--)
[ 9436.262161][ C4] pc : expire_timers+0x9c/0x438
[ 9436.262164][ C4] lr : expire_timers+0x2a4/0x438
[ 9436.262168][ C4] sp : ffffffc010023dd0
[ 9436.262171][ C4] x29: ffffffc010023df0 x28: ffffffd0636fdc18
[ 9436.262178][ C4] x27: ffffffd063569dd0 x26: ffffffd063536008
[ 9436.262182][ C4] x25: 0000000000000001 x24: ffffff88f7c69280
[ 9436.262185][ C4] x23: 00000000000000e0 x22: dead000000000122
[ 9436.262188][ C4] x21: 000000010022da29 x20: ffffff8af72b4e80
[ 9436.262191][ C4] x19: ffffffc010023e50 x18: ffffffc010025038
[ 9436.262195][ C4] x17: 0000000000000240 x16: 0000000000000201
[ 9436.262199][ C4] x15: ffffffffffffffff x14: ffffff889f3c3100
[ 9436.262203][ C4] x13: ffffff889f3c3100 x12: 00000000049f56b8
[ 9436.262207][ C4] x11: 00000000049f56b8 x10: 00000000ffffffff
[ 9436.262212][ C4] x9 : ffffffc010023e50 x8 : dead000000000122
[ 9436.262216][ C4] x7 : ffffffffffffffff x6 : ffffffc0100239d8
[ 9436.262220][ C4] x5 : 0000000000000000 x4 : 0000000000000101
[ 9436.262223][ C4] x3 : 0000000000000080 x2 : ffffff8
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
iio: adc: ad7091r: Allow users to configure device events
AD7091R-5 devices are supported by the ad7091r-5 driver together with
the ad7091r-base driver. Those drivers declared iio events for notifying
user space when ADC readings fall bellow the thresholds of low limit
registers or above the values set in high limit registers.
However, to configure iio events and their thresholds, a set of callback
functions must be implemented and those were not present until now.
The consequence of trying to configure ad7091r-5 events without the
proper callback functions was a null pointer dereference in the kernel
because the pointers to the callback functions were not set.
Implement event configuration callbacks allowing users to read/write
event thresholds and enable/disable event generation.
Since the event spec structs are generic to AD7091R devices, also move
those from the ad7091r-5 driver the base driver so they can be reused
when support for ad7091r-2/-4/-8 be added. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid online resizing failures due to oversized flex bg
When we online resize an ext4 filesystem with a oversized flexbg_size,
mkfs.ext4 -F -G 67108864 $dev -b 4096 100M
mount $dev $dir
resize2fs $dev 16G
the following WARN_ON is triggered:
==================================================================
WARNING: CPU: 0 PID: 427 at mm/page_alloc.c:4402 __alloc_pages+0x411/0x550
Modules linked in: sg(E)
CPU: 0 PID: 427 Comm: resize2fs Tainted: G E 6.6.0-rc5+ #314
RIP: 0010:__alloc_pages+0x411/0x550
Call Trace:
<TASK>
__kmalloc_large_node+0xa2/0x200
__kmalloc+0x16e/0x290
ext4_resize_fs+0x481/0xd80
__ext4_ioctl+0x1616/0x1d90
ext4_ioctl+0x12/0x20
__x64_sys_ioctl+0xf0/0x150
do_syscall_64+0x3b/0x90
==================================================================
This is because flexbg_size is too large and the size of the new_group_data
array to be allocated exceeds MAX_ORDER. Currently, the minimum value of
MAX_ORDER is 8, the minimum value of PAGE_SIZE is 4096, the corresponding
maximum number of groups that can be allocated is:
(PAGE_SIZE << MAX_ORDER) / sizeof(struct ext4_new_group_data) ≈ 21845
And the value that is down-aligned to the power of 2 is 16384. Therefore,
this value is defined as MAX_RESIZE_BG, and the number of groups added
each time does not exceed this value during resizing, and is added multiple
times to complete the online resizing. The difference is that the metadata
in a flex_bg may be more dispersed. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: switchtec: Fix stdev_release() crash after surprise hot remove
A PCI device hot removal may occur while stdev->cdev is held open. The call
to stdev_release() then happens during close or exit, at a point way past
switchtec_pci_remove(). Otherwise the last ref would vanish with the
trailing put_device(), just before return.
At that later point in time, the devm cleanup has already removed the
stdev->mmio_mrpc mapping. Also, the stdev->pdev reference was not a counted
one. Therefore, in DMA mode, the iowrite32() in stdev_release() will cause
a fatal page fault, and the subsequent dma_free_coherent(), if reached,
would pass a stale &stdev->pdev->dev pointer.
Fix by moving MRPC DMA shutdown into switchtec_pci_remove(), after
stdev_kill(). Counting the stdev->pdev ref is now optional, but may prevent
future accidents.
Reproducible via the script at
https://lore.kernel.org/r/20231113212150.96410-1-dns@arista.com |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: lib/mpi - Fix unexpected pointer access in mpi_ec_init
When the mpi_ec_ctx structure is initialized, some fields are not
cleared, causing a crash when referencing the field when the
structure was released. Initially, this issue was ignored because
memory for mpi_ec_ctx is allocated with the __GFP_ZERO flag.
For example, this error will be triggered when calculating the
Za value for SM2 separately. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: scomp - fix req->dst buffer overflow
The req->dst buffer size should be checked before copying from the
scomp_scratch->dst to avoid req->dst buffer overflow problem. |
| In the Linux kernel, the following vulnerability has been resolved:
binder: fix race between mmput() and do_exit()
Task A calls binder_update_page_range() to allocate and insert pages on
a remote address space from Task B. For this, Task A pins the remote mm
via mmget_not_zero() first. This can race with Task B do_exit() and the
final mmput() refcount decrement will come from Task A.
Task A | Task B
------------------+------------------
mmget_not_zero() |
| do_exit()
| exit_mm()
| mmput()
mmput() |
exit_mmap() |
remove_vma() |
fput() |
In this case, the work of ____fput() from Task B is queued up in Task A
as TWA_RESUME. So in theory, Task A returns to userspace and the cleanup
work gets executed. However, Task A instead sleep, waiting for a reply
from Task B that never comes (it's dead).
This means the binder_deferred_release() is blocked until an unrelated
binder event forces Task A to go back to userspace. All the associated
death notifications will also be delayed until then.
In order to fix this use mmput_async() that will schedule the work in
the corresponding mm->async_put_work WQ instead of Task A. |
| In the Linux kernel, the following vulnerability has been resolved:
jfs: fix slab-out-of-bounds Read in dtSearch
Currently while searching for current page in the sorted entry table
of the page there is a out of bound access. Added a bound check to fix
the error.
Dave:
Set return code to -EIO |
| In the Linux kernel, the following vulnerability has been resolved:
jfs: fix array-index-out-of-bounds in dbAdjTree
Currently there is a bound check missing in the dbAdjTree while
accessing the dmt_stree. To add the required check added the bool is_ctl
which is required to determine the size as suggest in the following
commit.
https://lore.kernel.org/linux-kernel-mentees/f9475918-2186-49b8-b801-6f0f9e75f4fa@oracle.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: fix deadlock or deadcode of misusing dget()
The lock order is incorrect between denty and its parent, we should
always make sure that the parent get the lock first.
But since this deadcode is never used and the parent dir will always
be set from the callers, let's just remove it. |
| In the Linux kernel, the following vulnerability has been resolved:
dmaengine: fix NULL pointer in channel unregistration function
__dma_async_device_channel_register() can fail. In case of failure,
chan->local is freed (with free_percpu()), and chan->local is nullified.
When dma_async_device_unregister() is called (because of managed API or
intentionally by DMA controller driver), channels are unconditionally
unregistered, leading to this NULL pointer:
[ 1.318693] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
[...]
[ 1.484499] Call trace:
[ 1.486930] device_del+0x40/0x394
[ 1.490314] device_unregister+0x20/0x7c
[ 1.494220] __dma_async_device_channel_unregister+0x68/0xc0
Look at dma_async_device_register() function error path, channel device
unregistration is done only if chan->local is not NULL.
Then add the same condition at the beginning of
__dma_async_device_channel_unregister() function, to avoid NULL pointer
issue whatever the API used to reach this function. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/sparsemem: fix race in accessing memory_section->usage
The below race is observed on a PFN which falls into the device memory
region with the system memory configuration where PFN's are such that
[ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL]. Since normal zone start and end
pfn contains the device memory PFN's as well, the compaction triggered
will try on the device memory PFN's too though they end up in NOP(because
pfn_to_online_page() returns NULL for ZONE_DEVICE memory sections). When
from other core, the section mappings are being removed for the
ZONE_DEVICE region, that the PFN in question belongs to, on which
compaction is currently being operated is resulting into the kernel crash
with CONFIG_SPASEMEM_VMEMAP enabled. The crash logs can be seen at [1].
compact_zone() memunmap_pages
------------- ---------------
__pageblock_pfn_to_page
......
(a)pfn_valid():
valid_section()//return true
(b)__remove_pages()->
sparse_remove_section()->
section_deactivate():
[Free the array ms->usage and set
ms->usage = NULL]
pfn_section_valid()
[Access ms->usage which
is NULL]
NOTE: From the above it can be said that the race is reduced to between
the pfn_valid()/pfn_section_valid() and the section deactivate with
SPASEMEM_VMEMAP enabled.
The commit b943f045a9af("mm/sparse: fix kernel crash with
pfn_section_valid check") tried to address the same problem by clearing
the SECTION_HAS_MEM_MAP with the expectation of valid_section() returns
false thus ms->usage is not accessed.
Fix this issue by the below steps:
a) Clear SECTION_HAS_MEM_MAP before freeing the ->usage.
b) RCU protected read side critical section will either return NULL
when SECTION_HAS_MEM_MAP is cleared or can successfully access ->usage.
c) Free the ->usage with kfree_rcu() and set ms->usage = NULL. No
attempt will be made to access ->usage after this as the
SECTION_HAS_MEM_MAP is cleared thus valid_section() return false.
Thanks to David/Pavan for their inputs on this patch.
[1] https://lore.kernel.org/linux-mm/994410bb-89aa-d987-1f50-f514903c55aa@quicinc.com/
On Snapdragon SoC, with the mentioned memory configuration of PFN's as
[ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL], we are able to see bunch of
issues daily while testing on a device farm.
For this particular issue below is the log. Though the below log is
not directly pointing to the pfn_section_valid(){ ms->usage;}, when we
loaded this dump on T32 lauterbach tool, it is pointing.
[ 540.578056] Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000000
[ 540.578068] Mem abort info:
[ 540.578070] ESR = 0x0000000096000005
[ 540.578073] EC = 0x25: DABT (current EL), IL = 32 bits
[ 540.578077] SET = 0, FnV = 0
[ 540.578080] EA = 0, S1PTW = 0
[ 540.578082] FSC = 0x05: level 1 translation fault
[ 540.578085] Data abort info:
[ 540.578086] ISV = 0, ISS = 0x00000005
[ 540.578088] CM = 0, WnR = 0
[ 540.579431] pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBSBTYPE=--)
[ 540.579436] pc : __pageblock_pfn_to_page+0x6c/0x14c
[ 540.579454] lr : compact_zone+0x994/0x1058
[ 540.579460] sp : ffffffc03579b510
[ 540.579463] x29: ffffffc03579b510 x28: 0000000000235800 x27:000000000000000c
[ 540.579470] x26: 0000000000235c00 x25: 0000000000000068 x24:ffffffc03579b640
[ 540.579477] x23: 0000000000000001 x22: ffffffc03579b660 x21:0000000000000000
[ 540.579483] x20: 0000000000235bff x19: ffffffdebf7e3940 x18:ffffffdebf66d140
[ 540.579489] x17: 00000000739ba063 x16: 00000000739ba063 x15:00000000009f4bff
[ 540.579495] x14: 0000008000000000 x13: 0000000000000000 x12:0000000000000001
[ 540.579501] x11: 0000000000000000 x10: 0000000000000000 x9 :ffffff897d2cd440
[ 540.579507] x8 : 0000000000000000 x7 : 0000000000000000 x6 :ffffffc03579b5b4
[ 540.579512] x5 : 0000000000027f25 x4 : ffffffc03579b5b8 x3 :0000000000000
---truncated--- |