| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
sched/psi: Fix use-after-free in ep_remove_wait_queue()
If a non-root cgroup gets removed when there is a thread that registered
trigger and is polling on a pressure file within the cgroup, the polling
waitqueue gets freed in the following path:
do_rmdir
cgroup_rmdir
kernfs_drain_open_files
cgroup_file_release
cgroup_pressure_release
psi_trigger_destroy
However, the polling thread still has a reference to the pressure file and
will access the freed waitqueue when the file is closed or upon exit:
fput
ep_eventpoll_release
ep_free
ep_remove_wait_queue
remove_wait_queue
This results in use-after-free as pasted below.
The fundamental problem here is that cgroup_file_release() (and
consequently waitqueue's lifetime) is not tied to the file's real lifetime.
Using wake_up_pollfree() here might be less than ideal, but it is in line
with the comment at commit 42288cb44c4b ("wait: add wake_up_pollfree()")
since the waitqueue's lifetime is not tied to file's one and can be
considered as another special case. While this would be fixable by somehow
making cgroup_file_release() be tied to the fput(), it would require
sizable refactoring at cgroups or higher layer which might be more
justifiable if we identify more cases like this.
BUG: KASAN: use-after-free in _raw_spin_lock_irqsave+0x60/0xc0
Write of size 4 at addr ffff88810e625328 by task a.out/4404
CPU: 19 PID: 4404 Comm: a.out Not tainted 6.2.0-rc6 #38
Hardware name: Amazon EC2 c5a.8xlarge/, BIOS 1.0 10/16/2017
Call Trace:
<TASK>
dump_stack_lvl+0x73/0xa0
print_report+0x16c/0x4e0
kasan_report+0xc3/0xf0
kasan_check_range+0x2d2/0x310
_raw_spin_lock_irqsave+0x60/0xc0
remove_wait_queue+0x1a/0xa0
ep_free+0x12c/0x170
ep_eventpoll_release+0x26/0x30
__fput+0x202/0x400
task_work_run+0x11d/0x170
do_exit+0x495/0x1130
do_group_exit+0x100/0x100
get_signal+0xd67/0xde0
arch_do_signal_or_restart+0x2a/0x2b0
exit_to_user_mode_prepare+0x94/0x100
syscall_exit_to_user_mode+0x20/0x40
do_syscall_64+0x52/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Allocated by task 4404:
kasan_set_track+0x3d/0x60
__kasan_kmalloc+0x85/0x90
psi_trigger_create+0x113/0x3e0
pressure_write+0x146/0x2e0
cgroup_file_write+0x11c/0x250
kernfs_fop_write_iter+0x186/0x220
vfs_write+0x3d8/0x5c0
ksys_write+0x90/0x110
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Freed by task 4407:
kasan_set_track+0x3d/0x60
kasan_save_free_info+0x27/0x40
____kasan_slab_free+0x11d/0x170
slab_free_freelist_hook+0x87/0x150
__kmem_cache_free+0xcb/0x180
psi_trigger_destroy+0x2e8/0x310
cgroup_file_release+0x4f/0xb0
kernfs_drain_open_files+0x165/0x1f0
kernfs_drain+0x162/0x1a0
__kernfs_remove+0x1fb/0x310
kernfs_remove_by_name_ns+0x95/0xe0
cgroup_addrm_files+0x67f/0x700
cgroup_destroy_locked+0x283/0x3c0
cgroup_rmdir+0x29/0x100
kernfs_iop_rmdir+0xd1/0x140
vfs_rmdir+0xfe/0x240
do_rmdir+0x13d/0x280
__x64_sys_rmdir+0x2c/0x30
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| 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:
net/mlx5e: fix a potential double-free in fs_any_create_groups
When kcalloc() for ft->g succeeds but kvzalloc() for in fails,
fs_any_create_groups() will free ft->g. However, its caller
fs_any_create_table() will free ft->g again through calling
mlx5e_destroy_flow_table(), which will lead to a double-free.
Fix this by setting ft->g to NULL in fs_any_create_groups(). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: fix a memleak in vmw_gmrid_man_get_node
When ida_alloc_max fails, resources allocated before should be freed,
including *res allocated by kmalloc and ttm_resource_init. |
| In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: fix a memleak in gss_import_v2_context
The ctx->mech_used.data allocated by kmemdup is not freed in neither
gss_import_v2_context nor it only caller gss_krb5_import_sec_context,
which frees ctx on error.
Thus, this patch reform the last call of gss_import_v2_context to the
gss_krb5_import_ctx_v2, preventing the memleak while keepping the return
formation. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: vsie: fix race during shadow creation
Right now it is possible to see gmap->private being zero in
kvm_s390_vsie_gmap_notifier resulting in a crash. This is due to the
fact that we add gmap->private == kvm after creation:
static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
struct vsie_page *vsie_page)
{
[...]
gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
if (IS_ERR(gmap))
return PTR_ERR(gmap);
gmap->private = vcpu->kvm;
Let children inherit the private field of the parent. |
| In the Linux kernel, the following vulnerability has been resolved:
hwrng: core - Fix page fault dead lock on mmap-ed hwrng
There is a dead-lock in the hwrng device read path. This triggers
when the user reads from /dev/hwrng into memory also mmap-ed from
/dev/hwrng. The resulting page fault triggers a recursive read
which then dead-locks.
Fix this by using a stack buffer when calling copy_to_user. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_ct: fix skb leak and crash on ooo frags
act_ct adds skb->users before defragmentation. If frags arrive in order,
the last frag's reference is reset in:
inet_frag_reasm_prepare
skb_morph
which is not straightforward.
However when frags arrive out of order, nobody unref the last frag, and
all frags are leaked. The situation is even worse, as initiating packet
capture can lead to a crash[0] when skb has been cloned and shared at the
same time.
Fix the issue by removing skb_get() before defragmentation. act_ct
returns TC_ACT_CONSUMED when defrag failed or in progress.
[0]:
[ 843.804823] ------------[ cut here ]------------
[ 843.809659] kernel BUG at net/core/skbuff.c:2091!
[ 843.814516] invalid opcode: 0000 [#1] PREEMPT SMP
[ 843.819296] CPU: 7 PID: 0 Comm: swapper/7 Kdump: loaded Tainted: G S 6.7.0-rc3 #2
[ 843.824107] Hardware name: XFUSION 1288H V6/BC13MBSBD, BIOS 1.29 11/25/2022
[ 843.828953] RIP: 0010:pskb_expand_head+0x2ac/0x300
[ 843.833805] Code: 8b 70 28 48 85 f6 74 82 48 83 c6 08 bf 01 00 00 00 e8 38 bd ff ff 8b 83 c0 00 00 00 48 03 83 c8 00 00 00 e9 62 ff ff ff 0f 0b <0f> 0b e8 8d d0 ff ff e9 b3 fd ff ff 81 7c 24 14 40 01 00 00 4c 89
[ 843.843698] RSP: 0018:ffffc9000cce07c0 EFLAGS: 00010202
[ 843.848524] RAX: 0000000000000002 RBX: ffff88811a211d00 RCX: 0000000000000820
[ 843.853299] RDX: 0000000000000640 RSI: 0000000000000000 RDI: ffff88811a211d00
[ 843.857974] RBP: ffff888127d39518 R08: 00000000bee97314 R09: 0000000000000000
[ 843.862584] R10: 0000000000000000 R11: ffff8881109f0000 R12: 0000000000000880
[ 843.867147] R13: ffff888127d39580 R14: 0000000000000640 R15: ffff888170f7b900
[ 843.871680] FS: 0000000000000000(0000) GS:ffff889ffffc0000(0000) knlGS:0000000000000000
[ 843.876242] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 843.880778] CR2: 00007fa42affcfb8 CR3: 000000011433a002 CR4: 0000000000770ef0
[ 843.885336] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 843.889809] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 843.894229] PKRU: 55555554
[ 843.898539] Call Trace:
[ 843.902772] <IRQ>
[ 843.906922] ? __die_body+0x1e/0x60
[ 843.911032] ? die+0x3c/0x60
[ 843.915037] ? do_trap+0xe2/0x110
[ 843.918911] ? pskb_expand_head+0x2ac/0x300
[ 843.922687] ? do_error_trap+0x65/0x80
[ 843.926342] ? pskb_expand_head+0x2ac/0x300
[ 843.929905] ? exc_invalid_op+0x50/0x60
[ 843.933398] ? pskb_expand_head+0x2ac/0x300
[ 843.936835] ? asm_exc_invalid_op+0x1a/0x20
[ 843.940226] ? pskb_expand_head+0x2ac/0x300
[ 843.943580] inet_frag_reasm_prepare+0xd1/0x240
[ 843.946904] ip_defrag+0x5d4/0x870
[ 843.950132] nf_ct_handle_fragments+0xec/0x130 [nf_conntrack]
[ 843.953334] tcf_ct_act+0x252/0xd90 [act_ct]
[ 843.956473] ? tcf_mirred_act+0x516/0x5a0 [act_mirred]
[ 843.959657] tcf_action_exec+0xa1/0x160
[ 843.962823] fl_classify+0x1db/0x1f0 [cls_flower]
[ 843.966010] ? skb_clone+0x53/0xc0
[ 843.969173] tcf_classify+0x24d/0x420
[ 843.972333] tc_run+0x8f/0xf0
[ 843.975465] __netif_receive_skb_core+0x67a/0x1080
[ 843.978634] ? dev_gro_receive+0x249/0x730
[ 843.981759] __netif_receive_skb_list_core+0x12d/0x260
[ 843.984869] netif_receive_skb_list_internal+0x1cb/0x2f0
[ 843.987957] ? mlx5e_handle_rx_cqe_mpwrq_rep+0xfa/0x1a0 [mlx5_core]
[ 843.991170] napi_complete_done+0x72/0x1a0
[ 843.994305] mlx5e_napi_poll+0x28c/0x6d0 [mlx5_core]
[ 843.997501] __napi_poll+0x25/0x1b0
[ 844.000627] net_rx_action+0x256/0x330
[ 844.003705] __do_softirq+0xb3/0x29b
[ 844.006718] irq_exit_rcu+0x9e/0xc0
[ 844.009672] common_interrupt+0x86/0xa0
[ 844.012537] </IRQ>
[ 844.015285] <TASK>
[ 844.017937] asm_common_interrupt+0x26/0x40
[ 844.020591] RIP: 0010:acpi_safe_halt+0x1b/0x20
[ 844.023247] Code: ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 65 48 8b 04 25 00 18 03 00 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 81 d0 44 00 fb
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net: bridge: use DEV_STATS_INC()
syzbot/KCSAN reported data-races in br_handle_frame_finish() [1]
This function can run from multiple cpus without mutual exclusion.
Adopt SMP safe DEV_STATS_INC() to update dev->stats fields.
Handles updates to dev->stats.tx_dropped while we are at it.
[1]
BUG: KCSAN: data-race in br_handle_frame_finish / br_handle_frame_finish
read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 1:
br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189
br_nf_hook_thresh+0x1ed/0x220
br_nf_pre_routing_finish_ipv6+0x50f/0x540
NF_HOOK include/linux/netfilter.h:304 [inline]
br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178
br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:272 [inline]
br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417
__netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417
__netif_receive_skb_one_core net/core/dev.c:5521 [inline]
__netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637
process_backlog+0x21f/0x380 net/core/dev.c:5965
__napi_poll+0x60/0x3b0 net/core/dev.c:6527
napi_poll net/core/dev.c:6594 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6727
__do_softirq+0xc1/0x265 kernel/softirq.c:553
run_ksoftirqd+0x17/0x20 kernel/softirq.c:921
smpboot_thread_fn+0x30a/0x4a0 kernel/smpboot.c:164
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 0:
br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189
br_nf_hook_thresh+0x1ed/0x220
br_nf_pre_routing_finish_ipv6+0x50f/0x540
NF_HOOK include/linux/netfilter.h:304 [inline]
br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178
br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:272 [inline]
br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417
__netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417
__netif_receive_skb_one_core net/core/dev.c:5521 [inline]
__netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637
process_backlog+0x21f/0x380 net/core/dev.c:5965
__napi_poll+0x60/0x3b0 net/core/dev.c:6527
napi_poll net/core/dev.c:6594 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6727
__do_softirq+0xc1/0x265 kernel/softirq.c:553
do_softirq+0x5e/0x90 kernel/softirq.c:454
__local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x1a8/0x1f0 net/batman-adv/translation-table.c:1356
batadv_tt_purge+0x2b/0x630 net/batman-adv/translation-table.c:3560
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
value changed: 0x00000000000d7190 -> 0x00000000000d7191
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14848 Comm: kworker/u4:11 Not tainted 6.6.0-rc1-syzkaller-00236-gad8a69f361b9 #0 |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: smsc75xx: Fix uninit-value access in __smsc75xx_read_reg
syzbot reported the following uninit-value access issue:
=====================================================
BUG: KMSAN: uninit-value in smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:975 [inline]
BUG: KMSAN: uninit-value in smsc75xx_bind+0x5c9/0x11e0 drivers/net/usb/smsc75xx.c:1482
CPU: 0 PID: 8696 Comm: kworker/0:3 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x21c/0x280 lib/dump_stack.c:118
kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
__msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:975 [inline]
smsc75xx_bind+0x5c9/0x11e0 drivers/net/usb/smsc75xx.c:1482
usbnet_probe+0x1152/0x3f90 drivers/net/usb/usbnet.c:1737
usb_probe_interface+0xece/0x1550 drivers/usb/core/driver.c:374
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_set_configuration+0x380f/0x3f10 drivers/usb/core/message.c:2032
usb_generic_driver_probe+0x138/0x300 drivers/usb/core/generic.c:241
usb_probe_device+0x311/0x490 drivers/usb/core/driver.c:272
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_new_device+0x1bd4/0x2a30 drivers/usb/core/hub.c:2554
hub_port_connect drivers/usb/core/hub.c:5208 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x5e7b/0x8a70 drivers/usb/core/hub.c:5576
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Local variable ----buf.i87@smsc75xx_bind created at:
__smsc75xx_read_reg drivers/net/usb/smsc75xx.c:83 [inline]
smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:968 [inline]
smsc75xx_bind+0x485/0x11e0 drivers/net/usb/smsc75xx.c:1482
__smsc75xx_read_reg drivers/net/usb/smsc75xx.c:83 [inline]
smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:968 [inline]
smsc75xx_bind+0x485/0x11e0 drivers/net/usb/smsc75xx.c:1482
This issue is caused because usbnet_read_cmd() reads less bytes than requested
(zero byte in the reproducer). In this case, 'buf' is not properly filled.
This patch fixes the issue by returning -ENODATA if usbnet_read_cmd() reads
less bytes than requested. |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86: think-lmi: Fix reference leak
If a duplicate attribute is found using kset_find_obj(), a reference
to that attribute is returned which needs to be disposed accordingly
using kobject_put(). Move the setting name validation into a separate
function to allow for this change without having to duplicate the
cleanup code for this setting.
As a side note, a very similar bug was fixed in
commit 7295a996fdab ("platform/x86: dell-sysman: Fix reference leak"),
so it seems that the bug was copied from that driver.
Compile-tested only. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_codec: Fix leaking content of local_codecs
The following memory leak can be observed when the controller supports
codecs which are stored in local_codecs list but the elements are never
freed:
unreferenced object 0xffff88800221d840 (size 32):
comm "kworker/u3:0", pid 36, jiffies 4294898739 (age 127.060s)
hex dump (first 32 bytes):
f8 d3 02 03 80 88 ff ff 80 d8 21 02 80 88 ff ff ..........!.....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffffb324f557>] __kmalloc+0x47/0x120
[<ffffffffb39ef37d>] hci_codec_list_add.isra.0+0x2d/0x160
[<ffffffffb39ef643>] hci_read_codec_capabilities+0x183/0x270
[<ffffffffb39ef9ab>] hci_read_supported_codecs+0x1bb/0x2d0
[<ffffffffb39f162e>] hci_read_local_codecs_sync+0x3e/0x60
[<ffffffffb39ff1b3>] hci_dev_open_sync+0x943/0x11e0
[<ffffffffb396d55d>] hci_power_on+0x10d/0x3f0
[<ffffffffb30c99b4>] process_one_work+0x404/0x800
[<ffffffffb30ca134>] worker_thread+0x374/0x670
[<ffffffffb30d9108>] kthread+0x188/0x1c0
[<ffffffffb304db6b>] ret_from_fork+0x2b/0x50
[<ffffffffb300206a>] ret_from_fork_asm+0x1a/0x30 |
| 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--- |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel/uncore: Fix NULL pointer dereference issue in upi_fill_topology()
Get logical socket id instead of physical id in discover_upi_topology()
to avoid out-of-bound access on 'upi = &type->topology[nid][idx];' line
that leads to NULL pointer dereference in upi_fill_topology() |
| In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix kernel NULL pointer dereference in gfs2_rgrp_dump
Syzkaller has reported a NULL pointer dereference when accessing
rgd->rd_rgl in gfs2_rgrp_dump(). This can happen when creating
rgd->rd_gl fails in read_rindex_entry(). Add a NULL pointer check in
gfs2_rgrp_dump() to prevent that. |
| In the Linux kernel, the following vulnerability has been resolved:
net: hns3: fix use-after-free bug in hclgevf_send_mbx_msg
Currently, the hns3_remove function firstly uninstall client instance,
and then uninstall acceletion engine device. The netdevice is freed in
client instance uninstall process, but acceletion engine device uninstall
process still use it to trace runtime information. This causes a use after
free problem.
So fixes it by check the instance register state to avoid use after free. |
| In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum: Protect driver from buggy firmware
When processing port up/down events generated by the device's firmware,
the driver protects itself from events reported for non-existent local
ports, but not the CPU port (local port 0), which exists, but lacks a
netdev.
This can result in a NULL pointer dereference when calling
netif_carrier_{on,off}().
Fix this by bailing early when processing an event reported for the CPU
port. Problem was only observed when running on top of a buggy emulator. |
| In the Linux kernel, the following vulnerability has been resolved:
can: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv
It will trigger UAF for rx_kref of j1939_priv as following.
cpu0 cpu1
j1939_sk_bind(socket0, ndev0, ...)
j1939_netdev_start
j1939_sk_bind(socket1, ndev0, ...)
j1939_netdev_start
j1939_priv_set
j1939_priv_get_by_ndev_locked
j1939_jsk_add
.....
j1939_netdev_stop
kref_put_lock(&priv->rx_kref, ...)
kref_get(&priv->rx_kref, ...)
REFCOUNT_WARN("addition on 0;...")
====================================================
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 20874 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0
RIP: 0010:refcount_warn_saturate+0x169/0x1e0
Call Trace:
j1939_netdev_start+0x68b/0x920
j1939_sk_bind+0x426/0xeb0
? security_socket_bind+0x83/0xb0
The rx_kref's kref_get() and kref_put() should use j1939_netdev_lock to
protect. |
| In the Linux kernel, the following vulnerability has been resolved:
net: qcom/emac: fix UAF in emac_remove
adpt is netdev private data and it cannot be
used after free_netdev() call. Using adpt after free_netdev()
can cause UAF bug. Fix it by moving free_netdev() at the end of the
function. |
