Security Vulnerabilities
- CVEs Published In August 2024
In the Linux kernel, the following vulnerability has been resolved:
netfilter: fix use-after-free in __nf_register_net_hook()
We must not dereference @new_hooks after nf_hook_mutex has been released,
because other threads might have freed our allocated hooks already.
BUG: KASAN: use-after-free in nf_hook_entries_get_hook_ops include/linux/netfilter.h:130 [inline]
BUG: KASAN: use-after-free in hooks_validate net/netfilter/core.c:171 [inline]
BUG: KASAN: use-after-free in __nf_register_net_hook+0x77a/0x820 net/netfilter/core.c:438
Read of size 2 at addr ffff88801c1a8000 by task syz-executor237/4430
CPU: 1 PID: 4430 Comm: syz-executor237 Not tainted 5.17.0-rc5-syzkaller-00306-g2293be58d6a1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
nf_hook_entries_get_hook_ops include/linux/netfilter.h:130 [inline]
hooks_validate net/netfilter/core.c:171 [inline]
__nf_register_net_hook+0x77a/0x820 net/netfilter/core.c:438
nf_register_net_hook+0x114/0x170 net/netfilter/core.c:571
nf_register_net_hooks+0x59/0xc0 net/netfilter/core.c:587
nf_synproxy_ipv6_init+0x85/0xe0 net/netfilter/nf_synproxy_core.c:1218
synproxy_tg6_check+0x30d/0x560 net/ipv6/netfilter/ip6t_SYNPROXY.c:81
xt_check_target+0x26c/0x9e0 net/netfilter/x_tables.c:1038
check_target net/ipv6/netfilter/ip6_tables.c:530 [inline]
find_check_entry.constprop.0+0x7f1/0x9e0 net/ipv6/netfilter/ip6_tables.c:573
translate_table+0xc8b/0x1750 net/ipv6/netfilter/ip6_tables.c:735
do_replace net/ipv6/netfilter/ip6_tables.c:1153 [inline]
do_ip6t_set_ctl+0x56e/0xb90 net/ipv6/netfilter/ip6_tables.c:1639
nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1024
rawv6_setsockopt+0xd3/0x6a0 net/ipv6/raw.c:1084
__sys_setsockopt+0x2db/0x610 net/socket.c:2180
__do_sys_setsockopt net/socket.c:2191 [inline]
__se_sys_setsockopt net/socket.c:2188 [inline]
__x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f65a1ace7d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 15 00 00 90 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 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f65a1a7f308 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f65a1ace7d9
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007f65a1b574c8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00007f65a1b55130
R13: 00007f65a1b574c0 R14: 00007f65a1b24090 R15: 0000000000022000
</TASK>
The buggy address belongs to the page:
page:ffffea0000706a00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c1a8
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001c1b108 ffffea000046dd08 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52dc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO), pid 4430, ts 1061781545818, free_ts 1061791488993
prep_new_page mm/page_alloc.c:2434 [inline]
get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
__alloc_pages_node include/linux/gfp.h:572 [inline]
alloc_pages_node include/linux/gfp.h:595 [inline]
kmalloc_large_node+0x62/0x130 mm/slub.c:4438
__kmalloc_node+0x35a/0x4a0 mm/slub.
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
blktrace: fix use after free for struct blk_trace
When tracing the whole disk, 'dropped' and 'msg' will be created
under 'q->debugfs_dir' and 'bt->dir' is NULL, thus blk_trace_free()
won't remove those files. What's worse, the following UAF can be
triggered because of accessing stale 'dropped' and 'msg':
==================================================================
BUG: KASAN: use-after-free in blk_dropped_read+0x89/0x100
Read of size 4 at addr ffff88816912f3d8 by task blktrace/1188
CPU: 27 PID: 1188 Comm: blktrace Not tainted 5.17.0-rc4-next-20220217+ #469
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-4
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
print_address_description.constprop.0.cold+0xab/0x381
? blk_dropped_read+0x89/0x100
? blk_dropped_read+0x89/0x100
kasan_report.cold+0x83/0xdf
? blk_dropped_read+0x89/0x100
kasan_check_range+0x140/0x1b0
blk_dropped_read+0x89/0x100
? blk_create_buf_file_callback+0x20/0x20
? kmem_cache_free+0xa1/0x500
? do_sys_openat2+0x258/0x460
full_proxy_read+0x8f/0xc0
vfs_read+0xc6/0x260
ksys_read+0xb9/0x150
? vfs_write+0x3d0/0x3d0
? fpregs_assert_state_consistent+0x55/0x60
? exit_to_user_mode_prepare+0x39/0x1e0
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fbc080d92fd
Code: ce 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 1
RSP: 002b:00007fbb95ff9cb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fbb95ff9dc0 RCX: 00007fbc080d92fd
RDX: 0000000000000100 RSI: 00007fbb95ff9cc0 RDI: 0000000000000045
RBP: 0000000000000045 R08: 0000000000406299 R09: 00000000fffffffd
R10: 000000000153afa0 R11: 0000000000000293 R12: 00007fbb780008c0
R13: 00007fbb78000938 R14: 0000000000608b30 R15: 00007fbb780029c8
</TASK>
Allocated by task 1050:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x81/0xa0
do_blk_trace_setup+0xcb/0x410
__blk_trace_setup+0xac/0x130
blk_trace_ioctl+0xe9/0x1c0
blkdev_ioctl+0xf1/0x390
__x64_sys_ioctl+0xa5/0xe0
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 1050:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0x103/0x180
kfree+0x9a/0x4c0
__blk_trace_remove+0x53/0x70
blk_trace_ioctl+0x199/0x1c0
blkdev_common_ioctl+0x5e9/0xb30
blkdev_ioctl+0x1a5/0x390
__x64_sys_ioctl+0xa5/0xe0
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
The buggy address belongs to the object at ffff88816912f380
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 88 bytes inside of
96-byte region [ffff88816912f380, ffff88816912f3e0)
The buggy address belongs to the page:
page:000000009a1b4e7c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0f
flags: 0x17ffffc0000200(slab|node=0|zone=2|lastcpupid=0x1fffff)
raw: 0017ffffc0000200 ffffea00044f1100 dead000000000002 ffff88810004c780
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88816912f280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff88816912f300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88816912f380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff88816912f400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff88816912f480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================
In the Linux kernel, the following vulnerability has been resolved:
xen/netfront: destroy queues before real_num_tx_queues is zeroed
xennet_destroy_queues() relies on info->netdev->real_num_tx_queues to
delete queues. Since d7dac083414eb5bb99a6d2ed53dc2c1b405224e5
("net-sysfs: update the queue counts in the unregistration path"),
unregister_netdev() indirectly sets real_num_tx_queues to 0. Those two
facts together means, that xennet_destroy_queues() called from
xennet_remove() cannot do its job, because it's called after
unregister_netdev(). This results in kfree-ing queues that are still
linked in napi, which ultimately crashes:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 1 PID: 52 Comm: xenwatch Tainted: G W 5.16.10-1.32.fc32.qubes.x86_64+ #226
RIP: 0010:free_netdev+0xa3/0x1a0
Code: ff 48 89 df e8 2e e9 00 00 48 8b 43 50 48 8b 08 48 8d b8 a0 fe ff ff 48 8d a9 a0 fe ff ff 49 39 c4 75 26 eb 47 e8 ed c1 66 ff <48> 8b 85 60 01 00 00 48 8d 95 60 01 00 00 48 89 ef 48 2d 60 01 00
RSP: 0000:ffffc90000bcfd00 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88800edad000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffc90000bcfc30 RDI: 00000000ffffffff
RBP: fffffffffffffea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800edad050
R13: ffff8880065f8f88 R14: 0000000000000000 R15: ffff8880066c6680
FS: 0000000000000000(0000) GS:ffff8880f3300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000e998c006 CR4: 00000000003706e0
Call Trace:
<TASK>
xennet_remove+0x13d/0x300 [xen_netfront]
xenbus_dev_remove+0x6d/0xf0
__device_release_driver+0x17a/0x240
device_release_driver+0x24/0x30
bus_remove_device+0xd8/0x140
device_del+0x18b/0x410
? _raw_spin_unlock+0x16/0x30
? klist_iter_exit+0x14/0x20
? xenbus_dev_request_and_reply+0x80/0x80
device_unregister+0x13/0x60
xenbus_dev_changed+0x18e/0x1f0
xenwatch_thread+0xc0/0x1a0
? do_wait_intr_irq+0xa0/0xa0
kthread+0x16b/0x190
? set_kthread_struct+0x40/0x40
ret_from_fork+0x22/0x30
</TASK>
Fix this by calling xennet_destroy_queues() from xennet_uninit(),
when real_num_tx_queues is still available. This ensures that queues are
destroyed when real_num_tx_queues is set to 0, regardless of how
unregister_netdev() was called.
Originally reported at
https://github.com/QubesOS/qubes-issues/issues/7257
In the Linux kernel, the following vulnerability has been resolved:
thermal: core: Fix TZ_GET_TRIP NULL pointer dereference
Do not call get_trip_hyst() from thermal_genl_cmd_tz_get_trip() if
the thermal zone does not define one.
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Fix double list_add when enabling VMD in scalable mode
When enabling VMD and IOMMU scalable mode, the following kernel panic
call trace/kernel log is shown in Eagle Stream platform (Sapphire Rapids
CPU) during booting:
pci 0000:59:00.5: Adding to iommu group 42
...
vmd 0000:59:00.5: PCI host bridge to bus 10000:80
pci 10000:80:01.0: [8086:352a] type 01 class 0x060400
pci 10000:80:01.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:01.0: enabling Extended Tags
pci 10000:80:01.0: PME# supported from D0 D3hot D3cold
pci 10000:80:01.0: DMAR: Setup RID2PASID failed
pci 10000:80:01.0: Failed to add to iommu group 42: -16
pci 10000:80:03.0: [8086:352b] type 01 class 0x060400
pci 10000:80:03.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:03.0: enabling Extended Tags
pci 10000:80:03.0: PME# supported from D0 D3hot D3cold
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:29!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-rc3+ #7
Hardware name: Lenovo ThinkSystem SR650V3/SB27A86647, BIOS ESE101Y-1.00 01/13/2022
Workqueue: events work_for_cpu_fn
RIP: 0010:__list_add_valid.cold+0x26/0x3f
Code: 9a 4a ab ff 4c 89 c1 48 c7 c7 40 0c d9 9e e8 b9 b1 fe ff 0f
0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 f0 0c d9 9e e8 a2 b1
fe ff <0f> 0b 48 89 d1 4c 89 c6 4c 89 ca 48 c7 c7 98 0c d9
9e e8 8b b1 fe
RSP: 0000:ff5ad434865b3a40 EFLAGS: 00010246
RAX: 0000000000000058 RBX: ff4d61160b74b880 RCX: ff4d61255e1fffa8
RDX: 0000000000000000 RSI: 00000000fffeffff RDI: ffffffff9fd34f20
RBP: ff4d611d8e245c00 R08: 0000000000000000 R09: ff5ad434865b3888
R10: ff5ad434865b3880 R11: ff4d61257fdc6fe8 R12: ff4d61160b74b8a0
R13: ff4d61160b74b8a0 R14: ff4d611d8e245c10 R15: ff4d611d8001ba70
FS: 0000000000000000(0000) GS:ff4d611d5ea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ff4d611fa1401000 CR3: 0000000aa0210001 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
intel_pasid_alloc_table+0x9c/0x1d0
dmar_insert_one_dev_info+0x423/0x540
? device_to_iommu+0x12d/0x2f0
intel_iommu_attach_device+0x116/0x290
__iommu_attach_device+0x1a/0x90
iommu_group_add_device+0x190/0x2c0
__iommu_probe_device+0x13e/0x250
iommu_probe_device+0x24/0x150
iommu_bus_notifier+0x69/0x90
blocking_notifier_call_chain+0x5a/0x80
device_add+0x3db/0x7b0
? arch_memremap_can_ram_remap+0x19/0x50
? memremap+0x75/0x140
pci_device_add+0x193/0x1d0
pci_scan_single_device+0xb9/0xf0
pci_scan_slot+0x4c/0x110
pci_scan_child_bus_extend+0x3a/0x290
vmd_enable_domain.constprop.0+0x63e/0x820
vmd_probe+0x163/0x190
local_pci_probe+0x42/0x80
work_for_cpu_fn+0x13/0x20
process_one_work+0x1e2/0x3b0
worker_thread+0x1c4/0x3a0
? rescuer_thread+0x370/0x370
kthread+0xc7/0xf0
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
...
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x1ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]---
The following 'lspci' output shows devices '10000:80:*' are subdevices of
the VMD device 0000:59:00.5:
$ lspci
...
0000:59:00.5 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller (rev 20)
...
10000:80:01.0 PCI bridge: Intel Corporation Device 352a (rev 03)
10000:80:03.0 PCI bridge: Intel Corporation Device 352b (rev 03)
10000:80:05.0 PCI bridge: Intel Corporation Device 352c (rev 03)
10000:80:07.0 PCI bridge: Intel Corporation Device 352d (rev 03)
10000:81:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]
10000:82:00
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
iwlwifi: mvm: check debugfs_dir ptr before use
When "debugfs=off" is used on the kernel command line, iwiwifi's
mvm module uses an invalid/unchecked debugfs_dir pointer and causes
a BUG:
BUG: kernel NULL pointer dereference, address: 000000000000004f
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 1 PID: 503 Comm: modprobe Tainted: G W 5.17.0-rc5 #7
Hardware name: Dell Inc. Inspiron 15 5510/076F7Y, BIOS 2.4.1 11/05/2021
RIP: 0010:iwl_mvm_dbgfs_register+0x692/0x700 [iwlmvm]
Code: 69 a0 be 80 01 00 00 48 c7 c7 50 73 6a a0 e8 95 cf ee e0 48 8b 83 b0 1e 00 00 48 c7 c2 54 73 6a a0 be 64 00 00 00 48 8d 7d 8c <48> 8b 48 50 e8 15 22 07 e1 48 8b 43 28 48 8d 55 8c 48 c7 c7 5f 73
RSP: 0018:ffffc90000a0ba68 EFLAGS: 00010246
RAX: ffffffffffffffff RBX: ffff88817d6e3328 RCX: ffff88817d6e3328
RDX: ffffffffa06a7354 RSI: 0000000000000064 RDI: ffffc90000a0ba6c
RBP: ffffc90000a0bae0 R08: ffffffff824e4880 R09: ffffffffa069d620
R10: ffffc90000a0ba00 R11: ffffffffffffffff R12: 0000000000000000
R13: ffffc90000a0bb28 R14: ffff88817d6e3328 R15: ffff88817d6e3320
FS: 00007f64dd92d740(0000) GS:ffff88847f640000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000004f CR3: 000000016fc79001 CR4: 0000000000770ee0
PKRU: 55555554
Call Trace:
<TASK>
? iwl_mvm_mac_setup_register+0xbdc/0xda0 [iwlmvm]
iwl_mvm_start_post_nvm+0x71/0x100 [iwlmvm]
iwl_op_mode_mvm_start+0xab8/0xb30 [iwlmvm]
_iwl_op_mode_start+0x6f/0xd0 [iwlwifi]
iwl_opmode_register+0x6a/0xe0 [iwlwifi]
? 0xffffffffa0231000
iwl_mvm_init+0x35/0x1000 [iwlmvm]
? 0xffffffffa0231000
do_one_initcall+0x5a/0x1b0
? kmem_cache_alloc+0x1e5/0x2f0
? do_init_module+0x1e/0x220
do_init_module+0x48/0x220
load_module+0x2602/0x2bc0
? __kernel_read+0x145/0x2e0
? kernel_read_file+0x229/0x290
__do_sys_finit_module+0xc5/0x130
? __do_sys_finit_module+0xc5/0x130
__x64_sys_finit_module+0x13/0x20
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f64dda564dd
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 1b 29 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007ffdba393f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64dda564dd
RDX: 0000000000000000 RSI: 00005575399e2ab2 RDI: 0000000000000001
RBP: 000055753a91c5e0 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000000246 R12: 00005575399e2ab2
R13: 000055753a91ceb0 R14: 0000000000000000 R15: 000055753a923018
</TASK>
Modules linked in: btintel(+) btmtk bluetooth vfat snd_hda_codec_hdmi fat snd_hda_codec_realtek snd_hda_codec_generic iwlmvm(+) snd_sof_pci_intel_tgl mac80211 snd_sof_intel_hda_common soundwire_intel soundwire_generic_allocation soundwire_cadence soundwire_bus snd_sof_intel_hda snd_sof_pci snd_sof snd_sof_xtensa_dsp snd_soc_hdac_hda snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core btrfs snd_compress snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec raid6_pq iwlwifi snd_hda_core snd_pcm snd_timer snd soundcore cfg80211 intel_ish_ipc(+) thunderbolt rfkill intel_ishtp ucsi_acpi wmi i2c_hid_acpi i2c_hid evdev
CR2: 000000000000004f
---[ end trace 0000000000000000 ]---
Check the debugfs_dir pointer for an error before using it.
[change to make both conditional]
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix double free race when mount fails in cifs_get_root()
When cifs_get_root() fails during cifs_smb3_do_mount() we call
deactivate_locked_super() which eventually will call delayed_free() which
will free the context.
In this situation we should not proceed to enter the out: section in
cifs_smb3_do_mount() and free the same resources a second time.
[Thu Feb 10 12:59:06 2022] BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x32/0x60
[Thu Feb 10 12:59:06 2022] Read of size 8 at addr ffff888364f4d110 by task swapper/1/0
[Thu Feb 10 12:59:06 2022] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G OE 5.17.0-rc3+ #4
[Thu Feb 10 12:59:06 2022] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
[Thu Feb 10 12:59:06 2022] Call Trace:
[Thu Feb 10 12:59:06 2022] <IRQ>
[Thu Feb 10 12:59:06 2022] dump_stack_lvl+0x5d/0x78
[Thu Feb 10 12:59:06 2022] print_address_description.constprop.0+0x24/0x150
[Thu Feb 10 12:59:06 2022] ? rcu_cblist_dequeue+0x32/0x60
[Thu Feb 10 12:59:06 2022] kasan_report.cold+0x7d/0x117
[Thu Feb 10 12:59:06 2022] ? rcu_cblist_dequeue+0x32/0x60
[Thu Feb 10 12:59:06 2022] __asan_load8+0x86/0xa0
[Thu Feb 10 12:59:06 2022] rcu_cblist_dequeue+0x32/0x60
[Thu Feb 10 12:59:06 2022] rcu_core+0x547/0xca0
[Thu Feb 10 12:59:06 2022] ? call_rcu+0x3c0/0x3c0
[Thu Feb 10 12:59:06 2022] ? __this_cpu_preempt_check+0x13/0x20
[Thu Feb 10 12:59:06 2022] ? lock_is_held_type+0xea/0x140
[Thu Feb 10 12:59:06 2022] rcu_core_si+0xe/0x10
[Thu Feb 10 12:59:06 2022] __do_softirq+0x1d4/0x67b
[Thu Feb 10 12:59:06 2022] __irq_exit_rcu+0x100/0x150
[Thu Feb 10 12:59:06 2022] irq_exit_rcu+0xe/0x30
[Thu Feb 10 12:59:06 2022] sysvec_hyperv_stimer0+0x9d/0xc0
...
[Thu Feb 10 12:59:07 2022] Freed by task 58179:
[Thu Feb 10 12:59:07 2022] kasan_save_stack+0x26/0x50
[Thu Feb 10 12:59:07 2022] kasan_set_track+0x25/0x30
[Thu Feb 10 12:59:07 2022] kasan_set_free_info+0x24/0x40
[Thu Feb 10 12:59:07 2022] ____kasan_slab_free+0x137/0x170
[Thu Feb 10 12:59:07 2022] __kasan_slab_free+0x12/0x20
[Thu Feb 10 12:59:07 2022] slab_free_freelist_hook+0xb3/0x1d0
[Thu Feb 10 12:59:07 2022] kfree+0xcd/0x520
[Thu Feb 10 12:59:07 2022] cifs_smb3_do_mount+0x149/0xbe0 [cifs]
[Thu Feb 10 12:59:07 2022] smb3_get_tree+0x1a0/0x2e0 [cifs]
[Thu Feb 10 12:59:07 2022] vfs_get_tree+0x52/0x140
[Thu Feb 10 12:59:07 2022] path_mount+0x635/0x10c0
[Thu Feb 10 12:59:07 2022] __x64_sys_mount+0x1bf/0x210
[Thu Feb 10 12:59:07 2022] do_syscall_64+0x5c/0xc0
[Thu Feb 10 12:59:07 2022] entry_SYSCALL_64_after_hwframe+0x44/0xae
[Thu Feb 10 12:59:07 2022] Last potentially related work creation:
[Thu Feb 10 12:59:07 2022] kasan_save_stack+0x26/0x50
[Thu Feb 10 12:59:07 2022] __kasan_record_aux_stack+0xb6/0xc0
[Thu Feb 10 12:59:07 2022] kasan_record_aux_stack_noalloc+0xb/0x10
[Thu Feb 10 12:59:07 2022] call_rcu+0x76/0x3c0
[Thu Feb 10 12:59:07 2022] cifs_umount+0xce/0xe0 [cifs]
[Thu Feb 10 12:59:07 2022] cifs_kill_sb+0xc8/0xe0 [cifs]
[Thu Feb 10 12:59:07 2022] deactivate_locked_super+0x5d/0xd0
[Thu Feb 10 12:59:07 2022] cifs_smb3_do_mount+0xab9/0xbe0 [cifs]
[Thu Feb 10 12:59:07 2022] smb3_get_tree+0x1a0/0x2e0 [cifs]
[Thu Feb 10 12:59:07 2022] vfs_get_tree+0x52/0x140
[Thu Feb 10 12:59:07 2022] path_mount+0x635/0x10c0
[Thu Feb 10 12:59:07 2022] __x64_sys_mount+0x1bf/0x210
[Thu Feb 10 12:59:07 2022] do_syscall_64+0x5c/0xc0
[Thu Feb 10 12:59:07 2022] entry_SYSCALL_64_after_hwframe+0x44/0xae
In the Linux kernel, the following vulnerability has been resolved:
spi: spi-zynq-qspi: Fix a NULL pointer dereference in zynq_qspi_exec_mem_op()
In zynq_qspi_exec_mem_op(), kzalloc() is directly used in memset(),
which could lead to a NULL pointer dereference on failure of
kzalloc().
Fix this bug by adding a check of tmpbuf.
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_SPI_ZYNQ_QSPI=m show no new warnings,
and our static analyzer no longer warns about this code.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not start relocation until in progress drops are done
We hit a bug with a recovering relocation on mount for one of our file
systems in production. I reproduced this locally by injecting errors
into snapshot delete with balance running at the same time. This
presented as an error while looking up an extent item
WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680
CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8
RIP: 0010:lookup_inline_extent_backref+0x647/0x680
RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000
RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001
R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000
R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000
FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0
Call Trace:
<TASK>
insert_inline_extent_backref+0x46/0xd0
__btrfs_inc_extent_ref.isra.0+0x5f/0x200
? btrfs_merge_delayed_refs+0x164/0x190
__btrfs_run_delayed_refs+0x561/0xfa0
? btrfs_search_slot+0x7b4/0xb30
? btrfs_update_root+0x1a9/0x2c0
btrfs_run_delayed_refs+0x73/0x1f0
? btrfs_update_root+0x1a9/0x2c0
btrfs_commit_transaction+0x50/0xa50
? btrfs_update_reloc_root+0x122/0x220
prepare_to_merge+0x29f/0x320
relocate_block_group+0x2b8/0x550
btrfs_relocate_block_group+0x1a6/0x350
btrfs_relocate_chunk+0x27/0xe0
btrfs_balance+0x777/0xe60
balance_kthread+0x35/0x50
? btrfs_balance+0xe60/0xe60
kthread+0x16b/0x190
? set_kthread_struct+0x40/0x40
ret_from_fork+0x22/0x30
</TASK>
Normally snapshot deletion and relocation are excluded from running at
the same time by the fs_info->cleaner_mutex. However if we had a
pending balance waiting to get the ->cleaner_mutex, and a snapshot
deletion was running, and then the box crashed, we would come up in a
state where we have a half deleted snapshot.
Again, in the normal case the snapshot deletion needs to complete before
relocation can start, but in this case relocation could very well start
before the snapshot deletion completes, as we simply add the root to the
dead roots list and wait for the next time the cleaner runs to clean up
the snapshot.
Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that
had a pending drop_progress key. If they do then we know we were in the
middle of the drop operation and set a flag on the fs_info. Then
balance can wait until this flag is cleared to start up again.
If there are DEAD_ROOT's that don't have a drop_progress set then we're
safe to start balance right away as we'll be properly protected by the
cleaner_mutex.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not WARN_ON() if we have PageError set
Whenever we do any extent buffer operations we call
assert_eb_page_uptodate() to complain loudly if we're operating on an
non-uptodate page. Our overnight tests caught this warning earlier this
week
WARNING: CPU: 1 PID: 553508 at fs/btrfs/extent_io.c:6849 assert_eb_page_uptodate+0x3f/0x50
CPU: 1 PID: 553508 Comm: kworker/u4:13 Tainted: G W 5.17.0-rc3+ #564
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
Workqueue: btrfs-cache btrfs_work_helper
RIP: 0010:assert_eb_page_uptodate+0x3f/0x50
RSP: 0018:ffffa961440a7c68 EFLAGS: 00010246
RAX: 0017ffffc0002112 RBX: ffffe6e74453f9c0 RCX: 0000000000001000
RDX: ffffe6e74467c887 RSI: ffffe6e74453f9c0 RDI: ffff8d4c5efc2fc0
RBP: 0000000000000d56 R08: ffff8d4d4a224000 R09: 0000000000000000
R10: 00015817fa9d1ef0 R11: 000000000000000c R12: 00000000000007b1
R13: ffff8d4c5efc2fc0 R14: 0000000001500000 R15: 0000000001cb1000
FS: 0000000000000000(0000) GS:ffff8d4dbbd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff31d3448d8 CR3: 0000000118be8004 CR4: 0000000000370ee0
Call Trace:
extent_buffer_test_bit+0x3f/0x70
free_space_test_bit+0xa6/0xc0
load_free_space_tree+0x1f6/0x470
caching_thread+0x454/0x630
? rcu_read_lock_sched_held+0x12/0x60
? rcu_read_lock_sched_held+0x12/0x60
? rcu_read_lock_sched_held+0x12/0x60
? lock_release+0x1f0/0x2d0
btrfs_work_helper+0xf2/0x3e0
? lock_release+0x1f0/0x2d0
? finish_task_switch.isra.0+0xf9/0x3a0
process_one_work+0x26d/0x580
? process_one_work+0x580/0x580
worker_thread+0x55/0x3b0
? process_one_work+0x580/0x580
kthread+0xf0/0x120
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
This was partially fixed by c2e39305299f01 ("btrfs: clear extent buffer
uptodate when we fail to write it"), however all that fix did was keep
us from finding extent buffers after a failed writeout. It didn't keep
us from continuing to use a buffer that we already had found.
In this case we're searching the commit root to cache the block group,
so we can start committing the transaction and switch the commit root
and then start writing. After the switch we can look up an extent
buffer that hasn't been written yet and start processing that block
group. Then we fail to write that block out and clear Uptodate on the
page, and then we start spewing these errors.
Normally we're protected by the tree lock to a certain degree here. If
we read a block we have that block read locked, and we block the writer
from locking the block before we submit it for the write. However this
isn't necessarily fool proof because the read could happen before we do
the submit_bio and after we locked and unlocked the extent buffer.
Also in this particular case we have path->skip_locking set, so that
won't save us here. We'll simply get a block that was valid when we
read it, but became invalid while we were using it.
What we really want is to catch the case where we've "read" a block but
it's not marked Uptodate. On read we ClearPageError(), so if we're
!Uptodate and !Error we know we didn't do the right thing for reading
the page.
Fix this by checking !Uptodate && !Error, this way we will not complain
if our buffer gets invalidated while we're using it, and we'll maintain
the spirit of the check which is to make sure we have a fully in-cache
block while we're messing with it.