In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix NULL pointer dereference in nilfs_palloc_commit_free_entry()
Syzbot reported a null-ptr-deref bug:
NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP
frequency < 30 seconds
general protection fault, probably for non-canonical address
0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 1 PID: 3603 Comm: segctord Not tainted
6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google
10/11/2022
RIP: 0010:nilfs_palloc_commit_free_entry+0xe5/0x6b0
fs/nilfs2/alloc.c:608
Code: 00 00 00 00 fc ff df 80 3c 02 00 0f 85 cd 05 00 00 48 b8 00 00 00
00 00 fc ff df 4c 8b 73 08 49 8d 7e 10 48 89 fa 48 c1 ea 03 <80> 3c 02
00 0f 85 26 05 00 00 49 8b 46 10 be a6 00 00 00 48 c7 c7
RSP: 0018:ffffc90003dff830 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: ffff88802594e218 RCX: 000000000000000d
RDX: 0000000000000002 RSI: 0000000000002000 RDI: 0000000000000010
RBP: ffff888071880222 R08: 0000000000000005 R09: 000000000000003f
R10: 000000000000000d R11: 0000000000000000 R12: ffff888071880158
R13: ffff88802594e220 R14: 0000000000000000 R15: 0000000000000004
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb1c08316a8 CR3: 0000000018560000 CR4: 0000000000350ee0
Call Trace:
<TASK>
nilfs_dat_commit_free fs/nilfs2/dat.c:114 [inline]
nilfs_dat_commit_end+0x464/0x5f0 fs/nilfs2/dat.c:193
nilfs_dat_commit_update+0x26/0x40 fs/nilfs2/dat.c:236
nilfs_btree_commit_update_v+0x87/0x4a0 fs/nilfs2/btree.c:1940
nilfs_btree_commit_propagate_v fs/nilfs2/btree.c:2016 [inline]
nilfs_btree_propagate_v fs/nilfs2/btree.c:2046 [inline]
nilfs_btree_propagate+0xa00/0xd60 fs/nilfs2/btree.c:2088
nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337
nilfs_collect_file_data+0x45/0xd0 fs/nilfs2/segment.c:568
nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1018
nilfs_segctor_scan_file+0x3f4/0x6f0 fs/nilfs2/segment.c:1067
nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1197 [inline]
nilfs_segctor_collect fs/nilfs2/segment.c:1503 [inline]
nilfs_segctor_do_construct+0x12fc/0x6af0 fs/nilfs2/segment.c:2045
nilfs_segctor_construct+0x8e3/0xb30 fs/nilfs2/segment.c:2379
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2487 [inline]
nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2570
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
...
If DAT metadata file is corrupted on disk, there is a case where
req->pr_desc_bh is NULL and blocknr is 0 at nilfs_dat_commit_end() during
a b-tree operation that cascadingly updates ancestor nodes of the b-tree,
because nilfs_dat_commit_alloc() for a lower level block can initialize
the blocknr on the same DAT entry between nilfs_dat_prepare_end() and
nilfs_dat_commit_end().
If this happens, nilfs_dat_commit_end() calls nilfs_dat_commit_free()
without valid buffer heads in req->pr_desc_bh and req->pr_bitmap_bh, and
causes the NULL pointer dereference above in
nilfs_palloc_commit_free_entry() function, which leads to a crash.
Fix this by adding a NULL check on req->pr_desc_bh and req->pr_bitmap_bh
before nilfs_palloc_commit_free_entry() in nilfs_dat_commit_free().
This also calls nilfs_error() in that case to notify that there is a fatal
flaw in the filesystem metadata and prevent further operations.
In the Linux kernel, the following vulnerability has been resolved:
ASoC: soc-pcm: Add NULL check in BE reparenting
Add NULL check in dpcm_be_reparent API, to handle
kernel NULL pointer dereference error.
The issue occurred in fuzzing test.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: Fix function prototype mismatch in snd_seq_expand_var_event
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed.
seq_copy_in_user() and seq_copy_in_kernel() did not have prototypes
matching snd_seq_dump_func_t. Adjust this and remove the casts. There
are not resulting binary output differences.
This was found as a result of Clang's new -Wcast-function-type-strict
flag, which is more sensitive than the simpler -Wcast-function-type,
which only checks for type width mismatches.
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix use-after-free during gpu recovery
[Why]
[ 754.862560] refcount_t: underflow; use-after-free.
[ 754.862898] Call Trace:
[ 754.862903] <TASK>
[ 754.862913] amdgpu_job_free_cb+0xc2/0xe1 [amdgpu]
[ 754.863543] drm_sched_main.cold+0x34/0x39 [amd_sched]
[How]
The fw_fence may be not init, check whether dma_fence_init
is performed before job free
In the Linux kernel, the following vulnerability has been resolved:
xen-netfront: Fix NULL sring after live migration
A NAPI is setup for each network sring to poll data to kernel
The sring with source host is destroyed before live migration and
new sring with target host is setup after live migration.
The NAPI for the old sring is not deleted until setup new sring
with target host after migration. With busy_poll/busy_read enabled,
the NAPI can be polled before got deleted when resume VM.
BUG: unable to handle kernel NULL pointer dereference at
0000000000000008
IP: xennet_poll+0xae/0xd20
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
Call Trace:
finish_task_switch+0x71/0x230
timerqueue_del+0x1d/0x40
hrtimer_try_to_cancel+0xb5/0x110
xennet_alloc_rx_buffers+0x2a0/0x2a0
napi_busy_loop+0xdb/0x270
sock_poll+0x87/0x90
do_sys_poll+0x26f/0x580
tracing_map_insert+0x1d4/0x2f0
event_hist_trigger+0x14a/0x260
finish_task_switch+0x71/0x230
__schedule+0x256/0x890
recalc_sigpending+0x1b/0x50
xen_sched_clock+0x15/0x20
__rb_reserve_next+0x12d/0x140
ring_buffer_lock_reserve+0x123/0x3d0
event_triggers_call+0x87/0xb0
trace_event_buffer_commit+0x1c4/0x210
xen_clocksource_get_cycles+0x15/0x20
ktime_get_ts64+0x51/0xf0
SyS_ppoll+0x160/0x1a0
SyS_ppoll+0x160/0x1a0
do_syscall_64+0x73/0x130
entry_SYSCALL_64_after_hwframe+0x41/0xa6
...
RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900
CR2: 0000000000000008
---[ end trace f8601785b354351c ]---
xen frontend should remove the NAPIs for the old srings before live
migration as the bond srings are destroyed
There is a tiny window between the srings are set to NULL and
the NAPIs are disabled, It is safe as the NAPI threads are still
frozen at that time
In the Linux kernel, the following vulnerability has been resolved:
HID: core: fix shift-out-of-bounds in hid_report_raw_event
Syzbot reported shift-out-of-bounds in hid_report_raw_event.
microsoft 0003:045E:07DA.0001: hid_field_extract() called with n (128) >
32! (swapper/0)
======================================================================
UBSAN: shift-out-of-bounds in drivers/hid/hid-core.c:1323:20
shift exponent 127 is too large for 32-bit type 'int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted
6.1.0-rc4-syzkaller-00159-g4bbf3422df78 #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS
Google 10/26/2022
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:151 [inline]
__ubsan_handle_shift_out_of_bounds+0x3a6/0x420 lib/ubsan.c:322
snto32 drivers/hid/hid-core.c:1323 [inline]
hid_input_fetch_field drivers/hid/hid-core.c:1572 [inline]
hid_process_report drivers/hid/hid-core.c:1665 [inline]
hid_report_raw_event+0xd56/0x18b0 drivers/hid/hid-core.c:1998
hid_input_report+0x408/0x4f0 drivers/hid/hid-core.c:2066
hid_irq_in+0x459/0x690 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x369/0x530 drivers/usb/core/hcd.c:1671
dummy_timer+0x86b/0x3110 drivers/usb/gadget/udc/dummy_hcd.c:1988
call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x76a/0x980 kernel/time/timer.c:1790
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
__do_softirq+0x277/0x75b kernel/softirq.c:571
__irq_exit_rcu+0xec/0x170 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
======================================================================
If the size of the integer (unsigned n) is bigger than 32 in snto32(),
shift exponent will be too large for 32-bit type 'int', resulting in a
shift-out-of-bounds bug.
Fix this by adding a check on the size of the integer (unsigned n) in
snto32(). To add support for n greater than 32 bits, set n to 32, if n
is greater than 32.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: fix array index out of bound error in DCN32 DML
[Why&How]
LinkCapacitySupport array is indexed with the number of voltage states and
not the number of max DPPs. Fix the error by changing the array
declaration to use the correct (larger) array size of total number of
voltage states.
In the Linux kernel, the following vulnerability has been resolved:
udf: Fix preallocation discarding at indirect extent boundary
When preallocation extent is the first one in the extent block, the
code would corrupt extent tree header instead. Fix the problem and use
udf_delete_aext() for deleting extent to avoid some code duplication.