Security Vulnerabilities
- CVEs Published In 2024
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Fix out_fput in iommufd_fault_alloc()
As fput() calls the file->f_op->release op, where fault obj and ictx are
getting released, there is no need to release these two after fput() one
more time, which would result in imbalanced refcounts:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 48 PID: 2369 at lib/refcount.c:31 refcount_warn_saturate+0x60/0x230
Call trace:
refcount_warn_saturate+0x60/0x230 (P)
refcount_warn_saturate+0x60/0x230 (L)
iommufd_fault_fops_release+0x9c/0xe0 [iommufd]
...
VFS: Close: file count is 0 (f_op=iommufd_fops [iommufd])
WARNING: CPU: 48 PID: 2369 at fs/open.c:1507 filp_flush+0x3c/0xf0
Call trace:
filp_flush+0x3c/0xf0 (P)
filp_flush+0x3c/0xf0 (L)
__arm64_sys_close+0x34/0x98
...
imbalanced put on file reference count
WARNING: CPU: 48 PID: 2369 at fs/file.c:74 __file_ref_put+0x100/0x138
Call trace:
__file_ref_put+0x100/0x138 (P)
__file_ref_put+0x100/0x138 (L)
__fput_sync+0x4c/0xd0
Drop those two lines to fix the warnings above.
In the Linux kernel, the following vulnerability has been resolved:
af_packet: avoid erroring out after sock_init_data() in packet_create()
After sock_init_data() the allocated sk object is attached to the provided
sock object. On error, packet_create() frees the sk object leaving the
dangling pointer in the sock object on return. Some other code may try
to use this pointer and cause use-after-free.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix atomic calls in ath12k_mac_op_set_bitrate_mask()
When I try to manually set bitrates:
iw wlan0 set bitrates legacy-2.4 1
I get sleeping from invalid context error, see below. Fix that by switching to
use recently introduced ieee80211_iterate_stations_mtx().
Do note that WCN6855 firmware is still crashing, I'm not sure if that firmware
even supports bitrate WMI commands and should we consider disabling
ath12k_mac_op_set_bitrate_mask() for WCN6855? But that's for another patch.
BUG: sleeping function called from invalid context at drivers/net/wireless/ath/ath12k/wmi.c:420
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 2236, name: iw
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
3 locks held by iw/2236:
#0: ffffffffabc6f1d8 (cb_lock){++++}-{3:3}, at: genl_rcv+0x14/0x40
#1: ffff888138410810 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: nl80211_pre_doit+0x54d/0x800 [cfg80211]
#2: ffffffffab2cfaa0 (rcu_read_lock){....}-{1:2}, at: ieee80211_iterate_stations_atomic+0x2f/0x200 [mac80211]
CPU: 3 UID: 0 PID: 2236 Comm: iw Not tainted 6.11.0-rc7-wt-ath+ #1772
Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021
Call Trace:
<TASK>
dump_stack_lvl+0xa4/0xe0
dump_stack+0x10/0x20
__might_resched+0x363/0x5a0
? __alloc_skb+0x165/0x340
__might_sleep+0xad/0x160
ath12k_wmi_cmd_send+0xb1/0x3d0 [ath12k]
? ath12k_wmi_init_wcn7850+0xa40/0xa40 [ath12k]
? __netdev_alloc_skb+0x45/0x7b0
? __asan_memset+0x39/0x40
? ath12k_wmi_alloc_skb+0xf0/0x150 [ath12k]
? reacquire_held_locks+0x4d0/0x4d0
ath12k_wmi_set_peer_param+0x340/0x5b0 [ath12k]
ath12k_mac_disable_peer_fixed_rate+0xa3/0x110 [ath12k]
? ath12k_mac_vdev_stop+0x4f0/0x4f0 [ath12k]
ieee80211_iterate_stations_atomic+0xd4/0x200 [mac80211]
ath12k_mac_op_set_bitrate_mask+0x5d2/0x1080 [ath12k]
? ath12k_mac_vif_chan+0x320/0x320 [ath12k]
drv_set_bitrate_mask+0x267/0x470 [mac80211]
ieee80211_set_bitrate_mask+0x4cc/0x8a0 [mac80211]
? __this_cpu_preempt_check+0x13/0x20
nl80211_set_tx_bitrate_mask+0x2bc/0x530 [cfg80211]
? nl80211_parse_tx_bitrate_mask+0x2320/0x2320 [cfg80211]
? trace_contention_end+0xef/0x140
? rtnl_unlock+0x9/0x10
? nl80211_pre_doit+0x557/0x800 [cfg80211]
genl_family_rcv_msg_doit+0x1f0/0x2e0
? genl_family_rcv_msg_attrs_parse.isra.0+0x250/0x250
? ns_capable+0x57/0xd0
genl_family_rcv_msg+0x34c/0x600
? genl_family_rcv_msg_dumpit+0x310/0x310
? __lock_acquire+0xc62/0x1de0
? he_set_mcs_mask.isra.0+0x8d0/0x8d0 [cfg80211]
? nl80211_parse_tx_bitrate_mask+0x2320/0x2320 [cfg80211]
? cfg80211_external_auth_request+0x690/0x690 [cfg80211]
genl_rcv_msg+0xa0/0x130
netlink_rcv_skb+0x14c/0x400
? genl_family_rcv_msg+0x600/0x600
? netlink_ack+0xd70/0xd70
? rwsem_optimistic_spin+0x4f0/0x4f0
? genl_rcv+0x14/0x40
? down_read_killable+0x580/0x580
? netlink_deliver_tap+0x13e/0x350
? __this_cpu_preempt_check+0x13/0x20
genl_rcv+0x23/0x40
netlink_unicast+0x45e/0x790
? netlink_attachskb+0x7f0/0x7f0
netlink_sendmsg+0x7eb/0xdb0
? netlink_unicast+0x790/0x790
? __this_cpu_preempt_check+0x13/0x20
? selinux_socket_sendmsg+0x31/0x40
? netlink_unicast+0x790/0x790
__sock_sendmsg+0xc9/0x160
____sys_sendmsg+0x620/0x990
? kernel_sendmsg+0x30/0x30
? __copy_msghdr+0x410/0x410
? __kasan_check_read+0x11/0x20
? mark_lock+0xe6/0x1470
___sys_sendmsg+0xe9/0x170
? copy_msghdr_from_user+0x120/0x120
? __lock_acquire+0xc62/0x1de0
? do_fault_around+0x2c6/0x4e0
? do_user_addr_fault+0x8c1/0xde0
? reacquire_held_locks+0x220/0x4d0
? do_user_addr_fault+0x8c1/0xde0
? __kasan_check_read+0x11/0x20
? __fdget+0x4e/0x1d0
? sockfd_lookup_light+0x1a/0x170
__sys_sendmsg+0xd2/0x180
? __sys_sendmsg_sock+0x20/0x20
? reacquire_held_locks+0x4d0/0x4d0
? debug_smp_processor_id+0x17/0x20
__x64_sys_sendmsg+0x72/0xb0
? lockdep_hardirqs_on+0x7d/0x100
x64_sys_call+0x894/0x9f0
do_syscall_64+0x64/0x130
entry_SYSCALL_64_after_
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix out-of-bounds access in 'dcn21_link_encoder_create'
An issue was identified in the dcn21_link_encoder_create function where
an out-of-bounds access could occur when the hpd_source index was used
to reference the link_enc_hpd_regs array. This array has a fixed size
and the index was not being checked against the array's bounds before
accessing it.
This fix adds a conditional check to ensure that the hpd_source index is
within the valid range of the link_enc_hpd_regs array. If the index is
out of bounds, the function now returns NULL to prevent undefined
behavior.
References:
[ 65.920507] ------------[ cut here ]------------
[ 65.920510] UBSAN: array-index-out-of-bounds in drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn21/dcn21_resource.c:1312:29
[ 65.920519] index 7 is out of range for type 'dcn10_link_enc_hpd_registers [5]'
[ 65.920523] CPU: 3 PID: 1178 Comm: modprobe Tainted: G OE 6.8.0-cleanershaderfeatureresetasdntipmi200nv2132 #13
[ 65.920525] Hardware name: AMD Majolica-RN/Majolica-RN, BIOS WMJ0429N_Weekly_20_04_2 04/29/2020
[ 65.920527] Call Trace:
[ 65.920529] <TASK>
[ 65.920532] dump_stack_lvl+0x48/0x70
[ 65.920541] dump_stack+0x10/0x20
[ 65.920543] __ubsan_handle_out_of_bounds+0xa2/0xe0
[ 65.920549] dcn21_link_encoder_create+0xd9/0x140 [amdgpu]
[ 65.921009] link_create+0x6d3/0xed0 [amdgpu]
[ 65.921355] create_links+0x18a/0x4e0 [amdgpu]
[ 65.921679] dc_create+0x360/0x720 [amdgpu]
[ 65.921999] ? dmi_matches+0xa0/0x220
[ 65.922004] amdgpu_dm_init+0x2b6/0x2c90 [amdgpu]
[ 65.922342] ? console_unlock+0x77/0x120
[ 65.922348] ? dev_printk_emit+0x86/0xb0
[ 65.922354] dm_hw_init+0x15/0x40 [amdgpu]
[ 65.922686] amdgpu_device_init+0x26a8/0x33a0 [amdgpu]
[ 65.922921] amdgpu_driver_load_kms+0x1b/0xa0 [amdgpu]
[ 65.923087] amdgpu_pci_probe+0x1b7/0x630 [amdgpu]
[ 65.923087] local_pci_probe+0x4b/0xb0
[ 65.923087] pci_device_probe+0xc8/0x280
[ 65.923087] really_probe+0x187/0x300
[ 65.923087] __driver_probe_device+0x85/0x130
[ 65.923087] driver_probe_device+0x24/0x110
[ 65.923087] __driver_attach+0xac/0x1d0
[ 65.923087] ? __pfx___driver_attach+0x10/0x10
[ 65.923087] bus_for_each_dev+0x7d/0xd0
[ 65.923087] driver_attach+0x1e/0x30
[ 65.923087] bus_add_driver+0xf2/0x200
[ 65.923087] driver_register+0x64/0x130
[ 65.923087] ? __pfx_amdgpu_init+0x10/0x10 [amdgpu]
[ 65.923087] __pci_register_driver+0x61/0x70
[ 65.923087] amdgpu_init+0x7d/0xff0 [amdgpu]
[ 65.923087] do_one_initcall+0x49/0x310
[ 65.923087] ? kmalloc_trace+0x136/0x360
[ 65.923087] do_init_module+0x6a/0x270
[ 65.923087] load_module+0x1fce/0x23a0
[ 65.923087] init_module_from_file+0x9c/0xe0
[ 65.923087] ? init_module_from_file+0x9c/0xe0
[ 65.923087] idempotent_init_module+0x179/0x230
[ 65.923087] __x64_sys_finit_module+0x5d/0xa0
[ 65.923087] do_syscall_64+0x76/0x120
[ 65.923087] entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 65.923087] RIP: 0033:0x7f2d80f1e88d
[ 65.923087] Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 b5 0f 00 f7 d8 64 89 01 48
[ 65.923087] RSP: 002b:00007ffc7bc1aa78 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 65.923087] RAX: ffffffffffffffda RBX: 0000564c9c1db130 RCX: 00007f2d80f1e88d
[ 65.923087] RDX: 0000000000000000 RSI: 0000564c9c1e5480 RDI: 000000000000000f
[ 65.923087] RBP: 0000000000040000 R08: 0000000000000000 R09: 0000000000000002
[ 65.923087] R10: 000000000000000f R11: 0000000000000246 R12: 0000564c9c1e5480
[ 65.923087] R13: 0000564c9c1db260 R14: 0000000000000000 R15: 0000564c9c1e54b0
[ 65.923087] </TASK>
[ 65.923927] ---[ end trace ]---
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: use ieee80211_purge_tx_queue() to purge TX skb
When removing kernel modules by:
rmmod rtw88_8723cs rtw88_8703b rtw88_8723x rtw88_sdio rtw88_core
Driver uses skb_queue_purge() to purge TX skb, but not report tx status
causing "Have pending ack frames!" warning. Use ieee80211_purge_tx_queue()
to correct this.
Since ieee80211_purge_tx_queue() doesn't take locks, to prevent racing
between TX work and purge TX queue, flush and destroy TX work in advance.
wlan0: deauthenticating from aa:f5:fd:60:4c:a8 by local
choice (Reason: 3=DEAUTH_LEAVING)
------------[ cut here ]------------
Have pending ack frames!
WARNING: CPU: 3 PID: 9232 at net/mac80211/main.c:1691
ieee80211_free_ack_frame+0x5c/0x90 [mac80211]
CPU: 3 PID: 9232 Comm: rmmod Tainted: G C
6.10.1-200.fc40.aarch64 #1
Hardware name: pine64 Pine64 PinePhone Braveheart
(1.1)/Pine64 PinePhone Braveheart (1.1), BIOS 2024.01 01/01/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : ieee80211_free_ack_frame+0x5c/0x90 [mac80211]
lr : ieee80211_free_ack_frame+0x5c/0x90 [mac80211]
sp : ffff80008c1b37b0
x29: ffff80008c1b37b0 x28: ffff000003be8000 x27: 0000000000000000
x26: 0000000000000000 x25: ffff000003dc14b8 x24: ffff80008c1b37d0
x23: ffff000000ff9f80 x22: 0000000000000000 x21: 000000007fffffff
x20: ffff80007c7e93d8 x19: ffff00006e66f400 x18: 0000000000000000
x17: ffff7ffffd2b3000 x16: ffff800083fc0000 x15: 0000000000000000
x14: 0000000000000000 x13: 2173656d61726620 x12: 6b636120676e6964
x11: 0000000000000000 x10: 000000000000005d x9 : ffff8000802af2b0
x8 : ffff80008c1b3430 x7 : 0000000000000001 x6 : 0000000000000001
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000003be8000
Call trace:
ieee80211_free_ack_frame+0x5c/0x90 [mac80211]
idr_for_each+0x74/0x110
ieee80211_free_hw+0x44/0xe8 [mac80211]
rtw_sdio_remove+0x9c/0xc0 [rtw88_sdio]
sdio_bus_remove+0x44/0x180
device_remove+0x54/0x90
device_release_driver_internal+0x1d4/0x238
driver_detach+0x54/0xc0
bus_remove_driver+0x78/0x108
driver_unregister+0x38/0x78
sdio_unregister_driver+0x2c/0x40
rtw_8723cs_driver_exit+0x18/0x1000 [rtw88_8723cs]
__do_sys_delete_module.isra.0+0x190/0x338
__arm64_sys_delete_module+0x1c/0x30
invoke_syscall+0x74/0x100
el0_svc_common.constprop.0+0x48/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x3c/0x158
el0t_64_sync_handler+0x120/0x138
el0t_64_sync+0x194/0x198
---[ end trace 0000000000000000 ]---
In the Linux kernel, the following vulnerability has been resolved:
kcsan: Turn report_filterlist_lock into a raw_spinlock
Ran Xiaokai reports that with a KCSAN-enabled PREEMPT_RT kernel, we can see
splats like:
| BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
| in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
| preempt_count: 10002, expected: 0
| RCU nest depth: 0, expected: 0
| no locks held by swapper/1/0.
| irq event stamp: 156674
| hardirqs last enabled at (156673): [<ffffffff81130bd9>] do_idle+0x1f9/0x240
| hardirqs last disabled at (156674): [<ffffffff82254f84>] sysvec_apic_timer_interrupt+0x14/0xc0
| softirqs last enabled at (0): [<ffffffff81099f47>] copy_process+0xfc7/0x4b60
| softirqs last disabled at (0): [<0000000000000000>] 0x0
| Preemption disabled at:
| [<ffffffff814a3e2a>] paint_ptr+0x2a/0x90
| CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.11.0+ #3
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
| Call Trace:
| <IRQ>
| dump_stack_lvl+0x7e/0xc0
| dump_stack+0x1d/0x30
| __might_resched+0x1a2/0x270
| rt_spin_lock+0x68/0x170
| kcsan_skip_report_debugfs+0x43/0xe0
| print_report+0xb5/0x590
| kcsan_report_known_origin+0x1b1/0x1d0
| kcsan_setup_watchpoint+0x348/0x650
| __tsan_unaligned_write1+0x16d/0x1d0
| hrtimer_interrupt+0x3d6/0x430
| __sysvec_apic_timer_interrupt+0xe8/0x3a0
| sysvec_apic_timer_interrupt+0x97/0xc0
| </IRQ>
On a detected data race, KCSAN's reporting logic checks if it should
filter the report. That list is protected by the report_filterlist_lock
*non-raw* spinlock which may sleep on RT kernels.
Since KCSAN may report data races in any context, convert it to a
raw_spinlock.
This requires being careful about when to allocate memory for the filter
list itself which can be done via KCSAN's debugfs interface. Concurrent
modification of the filter list via debugfs should be rare: the chosen
strategy is to optimistically pre-allocate memory before the critical
section and discard if unused.
In the Linux kernel, the following vulnerability has been resolved:
mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MM
We currently assume that there is at least one VMA in a MM, which isn't
true.
So we might end up having find_vma() return NULL, to then de-reference
NULL. So properly handle find_vma() returning NULL.
This fixes the report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 6021 Comm: syz-executor284 Not tainted 6.12.0-rc7-syzkaller-00187-gf868cd251776 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
RIP: 0010:migrate_to_node mm/mempolicy.c:1090 [inline]
RIP: 0010:do_migrate_pages+0x403/0x6f0 mm/mempolicy.c:1194
Code: ...
RSP: 0018:ffffc9000375fd08 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc9000375fd78 RCX: 0000000000000000
RDX: ffff88807e171300 RSI: dffffc0000000000 RDI: ffff88803390c044
RBP: ffff88807e171428 R08: 0000000000000014 R09: fffffbfff2039ef1
R10: ffffffff901cf78f R11: 0000000000000000 R12: 0000000000000003
R13: ffffc9000375fe90 R14: ffffc9000375fe98 R15: ffffc9000375fdf8
FS: 00005555919e1380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555919e1ca8 CR3: 000000007f12a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
kernel_migrate_pages+0x5b2/0x750 mm/mempolicy.c:1709
__do_sys_migrate_pages mm/mempolicy.c:1727 [inline]
__se_sys_migrate_pages mm/mempolicy.c:1723 [inline]
__x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1723
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
[akpm@linux-foundation.org: add unlikely()]
In the Linux kernel, the following vulnerability has been resolved:
mm/gup: handle NULL pages in unpin_user_pages()
The recent addition of "pofs" (pages or folios) handling to gup has a
flaw: it assumes that unpin_user_pages() handles NULL pages in the pages**
array. That's not the case, as I discovered when I ran on a new
configuration on my test machine.
Fix this by skipping NULL pages in unpin_user_pages(), just like
unpin_folios() already does.
Details: when booting on x86 with "numa=fake=2 movablecore=4G" on Linux
6.12, and running this:
tools/testing/selftests/mm/gup_longterm
...I get the following crash:
BUG: kernel NULL pointer dereference, address: 0000000000000008
RIP: 0010:sanity_check_pinned_pages+0x3a/0x2d0
...
Call Trace:
<TASK>
? __die_body+0x66/0xb0
? page_fault_oops+0x30c/0x3b0
? do_user_addr_fault+0x6c3/0x720
? irqentry_enter+0x34/0x60
? exc_page_fault+0x68/0x100
? asm_exc_page_fault+0x22/0x30
? sanity_check_pinned_pages+0x3a/0x2d0
unpin_user_pages+0x24/0xe0
check_and_migrate_movable_pages_or_folios+0x455/0x4b0
__gup_longterm_locked+0x3bf/0x820
? mmap_read_lock_killable+0x12/0x50
? __pfx_mmap_read_lock_killable+0x10/0x10
pin_user_pages+0x66/0xa0
gup_test_ioctl+0x358/0xb20
__se_sys_ioctl+0x6b/0xc0
do_syscall_64+0x7b/0x150
entry_SYSCALL_64_after_hwframe+0x76/0x7e
In the Linux kernel, the following vulnerability has been resolved:
sched/numa: fix memory leak due to the overwritten vma->numab_state
[Problem Description]
When running the hackbench program of LTP, the following memory leak is
reported by kmemleak.
# /opt/ltp/testcases/bin/hackbench 20 thread 1000
Running with 20*40 (== 800) tasks.
# dmesg | grep kmemleak
...
kmemleak: 480 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 665 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff888cd8ca2c40 (size 64):
comm "hackbench", pid 17142, jiffies 4299780315
hex dump (first 32 bytes):
ac 74 49 00 01 00 00 00 4c 84 49 00 01 00 00 00 .tI.....L.I.....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc bff18fd4):
[<ffffffff81419a89>] __kmalloc_cache_noprof+0x2f9/0x3f0
[<ffffffff8113f715>] task_numa_work+0x725/0xa00
[<ffffffff8110f878>] task_work_run+0x58/0x90
[<ffffffff81ddd9f8>] syscall_exit_to_user_mode+0x1c8/0x1e0
[<ffffffff81dd78d5>] do_syscall_64+0x85/0x150
[<ffffffff81e0012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
...
This issue can be consistently reproduced on three different servers:
* a 448-core server
* a 256-core server
* a 192-core server
[Root Cause]
Since multiple threads are created by the hackbench program (along with
the command argument 'thread'), a shared vma might be accessed by two or
more cores simultaneously. When two or more cores observe that
vma->numab_state is NULL at the same time, vma->numab_state will be
overwritten.
Although current code ensures that only one thread scans the VMAs in a
single 'numa_scan_period', there might be a chance for another thread
to enter in the next 'numa_scan_period' while we have not gotten till
numab_state allocation [1].
Note that the command `/opt/ltp/testcases/bin/hackbench 50 process 1000`
cannot the reproduce the issue. It is verified with 200+ test runs.
[Solution]
Use the cmpxchg atomic operation to ensure that only one thread executes
the vma->numab_state assignment.
[1] https://lore.kernel.org/lkml/1794be3c-358c-4cdc-a43d-a1f841d91ef7@amd.com/
In the Linux kernel, the following vulnerability has been resolved:
xsk: fix OOB map writes when deleting elements
Jordy says:
"
In the xsk_map_delete_elem function an unsigned integer
(map->max_entries) is compared with a user-controlled signed integer
(k). Due to implicit type conversion, a large unsigned value for
map->max_entries can bypass the intended bounds check:
if (k >= map->max_entries)
return -EINVAL;
This allows k to hold a negative value (between -2147483648 and -2),
which is then used as an array index in m->xsk_map[k], which results
in an out-of-bounds access.
spin_lock_bh(&m->lock);
map_entry = &m->xsk_map[k]; // Out-of-bounds map_entry
old_xs = unrcu_pointer(xchg(map_entry, NULL)); // Oob write
if (old_xs)
xsk_map_sock_delete(old_xs, map_entry);
spin_unlock_bh(&m->lock);
The xchg operation can then be used to cause an out-of-bounds write.
Moreover, the invalid map_entry passed to xsk_map_sock_delete can lead
to further memory corruption.
"
It indeed results in following splat:
[76612.897343] BUG: unable to handle page fault for address: ffffc8fc2e461108
[76612.904330] #PF: supervisor write access in kernel mode
[76612.909639] #PF: error_code(0x0002) - not-present page
[76612.914855] PGD 0 P4D 0
[76612.917431] Oops: Oops: 0002 [#1] PREEMPT SMP
[76612.921859] CPU: 11 UID: 0 PID: 10318 Comm: a.out Not tainted 6.12.0-rc1+ #470
[76612.929189] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019
[76612.939781] RIP: 0010:xsk_map_delete_elem+0x2d/0x60
[76612.944738] Code: 00 00 41 54 55 53 48 63 2e 3b 6f 24 73 38 4c 8d a7 f8 00 00 00 48 89 fb 4c 89 e7 e8 2d bf 05 00 48 8d b4 eb 00 01 00 00 31 ff <48> 87 3e 48 85 ff 74 05 e8 16 ff ff ff 4c 89 e7 e8 3e bc 05 00 31
[76612.963774] RSP: 0018:ffffc9002e407df8 EFLAGS: 00010246
[76612.969079] RAX: 0000000000000000 RBX: ffffc9002e461000 RCX: 0000000000000000
[76612.976323] RDX: 0000000000000001 RSI: ffffc8fc2e461108 RDI: 0000000000000000
[76612.983569] RBP: ffffffff80000001 R08: 0000000000000000 R09: 0000000000000007
[76612.990812] R10: ffffc9002e407e18 R11: ffff888108a38858 R12: ffffc9002e4610f8
[76612.998060] R13: ffff888108a38858 R14: 00007ffd1ae0ac78 R15: ffffc9002e4610c0
[76613.005303] FS: 00007f80b6f59740(0000) GS:ffff8897e0ec0000(0000) knlGS:0000000000000000
[76613.013517] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[76613.019349] CR2: ffffc8fc2e461108 CR3: 000000011e3ef001 CR4: 00000000007726f0
[76613.026595] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[76613.033841] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[76613.041086] PKRU: 55555554
[76613.043842] Call Trace:
[76613.046331] <TASK>
[76613.048468] ? __die+0x20/0x60
[76613.051581] ? page_fault_oops+0x15a/0x450
[76613.055747] ? search_extable+0x22/0x30
[76613.059649] ? search_bpf_extables+0x5f/0x80
[76613.063988] ? exc_page_fault+0xa9/0x140
[76613.067975] ? asm_exc_page_fault+0x22/0x30
[76613.072229] ? xsk_map_delete_elem+0x2d/0x60
[76613.076573] ? xsk_map_delete_elem+0x23/0x60
[76613.080914] __sys_bpf+0x19b7/0x23c0
[76613.084555] __x64_sys_bpf+0x1a/0x20
[76613.088194] do_syscall_64+0x37/0xb0
[76613.091832] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[76613.096962] RIP: 0033:0x7f80b6d1e88d
[76613.100592] Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 b5 0f 00 f7 d8 64 89 01 48
[76613.119631] RSP: 002b:00007ffd1ae0ac68 EFLAGS: 00000206 ORIG_RAX: 0000000000000141
[76613.131330] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f80b6d1e88d
[76613.142632] RDX: 0000000000000098 RSI: 00007ffd1ae0ad20 RDI: 0000000000000003
[76613.153967] RBP: 00007ffd1ae0adc0 R08: 0000000000000000 R09: 0000000000000000
[76613.166030] R10: 00007f80b6f77040 R11: 0000000000000206 R12: 00007ffd1ae0aed8
[76613.177130] R13: 000055ddf42ce1e9 R14: 000055ddf42d0d98 R15: 00
---truncated---