In the Linux kernel, the following vulnerability has been resolved:
PCI: Avoid pci_dev_lock() AB/BA deadlock with sriov_numvfs_store()
The sysfs sriov_numvfs_store() path acquires the device lock before the
config space access lock:
sriov_numvfs_store
device_lock # A (1) acquire device lock
sriov_configure
vfio_pci_sriov_configure # (for example)
vfio_pci_core_sriov_configure
pci_disable_sriov
sriov_disable
pci_cfg_access_lock
pci_wait_cfg # B (4) wait for dev->block_cfg_access == 0
Previously, pci_dev_lock() acquired the config space access lock before the
device lock:
pci_dev_lock
pci_cfg_access_lock
dev->block_cfg_access = 1 # B (2) set dev->block_cfg_access = 1
device_lock # A (3) wait for device lock
Any path that uses pci_dev_lock(), e.g., pci_reset_function(), may
deadlock with sriov_numvfs_store() if the operations occur in the sequence
(1) (2) (3) (4).
Avoid the deadlock by reversing the order in pci_dev_lock() so it acquires
the device lock before the config space access lock, the same as the
sriov_numvfs_store() path.
[bhelgaas: combined and adapted commit log from Jay Zhou's independent
subsequent posting:
https://lore.kernel.org/r/20220404062539.1710-1-jianjay.zhou@huawei.com]
In the Linux kernel, the following vulnerability has been resolved:
net: annotate races around sk->sk_bound_dev_if
UDP sendmsg() is lockless, and reads sk->sk_bound_dev_if while
this field can be changed by another thread.
Adds minimal annotations to avoid KCSAN splats for UDP.
Following patches will add more annotations to potential lockless readers.
BUG: KCSAN: data-race in __ip6_datagram_connect / udpv6_sendmsg
write to 0xffff888136d47a94 of 4 bytes by task 7681 on cpu 0:
__ip6_datagram_connect+0x6e2/0x930 net/ipv6/datagram.c:221
ip6_datagram_connect+0x2a/0x40 net/ipv6/datagram.c:272
inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576
__sys_connect_file net/socket.c:1900 [inline]
__sys_connect+0x197/0x1b0 net/socket.c:1917
__do_sys_connect net/socket.c:1927 [inline]
__se_sys_connect net/socket.c:1924 [inline]
__x64_sys_connect+0x3d/0x50 net/socket.c:1924
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
read to 0xffff888136d47a94 of 4 bytes by task 7670 on cpu 1:
udpv6_sendmsg+0xc60/0x16e0 net/ipv6/udp.c:1436
inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:652
sock_sendmsg_nosec net/socket.c:705 [inline]
sock_sendmsg net/socket.c:725 [inline]
____sys_sendmsg+0x39a/0x510 net/socket.c:2413
___sys_sendmsg net/socket.c:2467 [inline]
__sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
__do_sys_sendmmsg net/socket.c:2582 [inline]
__se_sys_sendmmsg net/socket.c:2579 [inline]
__x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
value changed: 0x00000000 -> 0xffffff9b
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7670 Comm: syz-executor.3 Tainted: G W 5.18.0-rc1-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
I chose to not add Fixes: tag because race has minor consequences
and stable teams busy enough.
In the Linux kernel, the following vulnerability has been resolved:
bfq: Avoid merging queues with different parents
It can happen that the parent of a bfqq changes between the moment we
decide two queues are worth to merge (and set bic->stable_merge_bfqq)
and the moment bfq_setup_merge() is called. This can happen e.g. because
the process submitted IO for a different cgroup and thus bfqq got
reparented. It can even happen that the bfqq we are merging with has
parent cgroup that is already offline and going to be destroyed in which
case the merge can lead to use-after-free issues such as:
BUG: KASAN: use-after-free in __bfq_deactivate_entity+0x9cb/0xa50
Read of size 8 at addr ffff88800693c0c0 by task runc:[2:INIT]/10544
CPU: 0 PID: 10544 Comm: runc:[2:INIT] Tainted: G E 5.15.2-0.g5fb85fd-default #1 openSUSE Tumbleweed (unreleased) f1f3b891c72369aebecd2e43e4641a6358867c70
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0x46/0x5a
print_address_description.constprop.0+0x1f/0x140
? __bfq_deactivate_entity+0x9cb/0xa50
kasan_report.cold+0x7f/0x11b
? __bfq_deactivate_entity+0x9cb/0xa50
__bfq_deactivate_entity+0x9cb/0xa50
? update_curr+0x32f/0x5d0
bfq_deactivate_entity+0xa0/0x1d0
bfq_del_bfqq_busy+0x28a/0x420
? resched_curr+0x116/0x1d0
? bfq_requeue_bfqq+0x70/0x70
? check_preempt_wakeup+0x52b/0xbc0
__bfq_bfqq_expire+0x1a2/0x270
bfq_bfqq_expire+0xd16/0x2160
? try_to_wake_up+0x4ee/0x1260
? bfq_end_wr_async_queues+0xe0/0xe0
? _raw_write_unlock_bh+0x60/0x60
? _raw_spin_lock_irq+0x81/0xe0
bfq_idle_slice_timer+0x109/0x280
? bfq_dispatch_request+0x4870/0x4870
__hrtimer_run_queues+0x37d/0x700
? enqueue_hrtimer+0x1b0/0x1b0
? kvm_clock_get_cycles+0xd/0x10
? ktime_get_update_offsets_now+0x6f/0x280
hrtimer_interrupt+0x2c8/0x740
Fix the problem by checking that the parent of the two bfqqs we are
merging in bfq_setup_merge() is the same.
In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid cycles in directory h-tree
A maliciously corrupted filesystem can contain cycles in the h-tree
stored inside a directory. That can easily lead to the kernel corrupting
tree nodes that were already verified under its hands while doing a node
split and consequently accessing unallocated memory. Fix the problem by
verifying traversed block numbers are unique.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock
When user_dlm_destroy_lock failed, it didn't clean up the flags it set
before exit. For USER_LOCK_IN_TEARDOWN, if this function fails because of
lock is still in used, next time when unlink invokes this function, it
will return succeed, and then unlink will remove inode and dentry if lock
is not in used(file closed), but the dlm lock is still linked in dlm lock
resource, then when bast come in, it will trigger a panic due to
user-after-free. See the following panic call trace. To fix this,
USER_LOCK_IN_TEARDOWN should be reverted if fail. And also error should
be returned if USER_LOCK_IN_TEARDOWN is set to let user know that unlink
fail.
For the case of ocfs2_dlm_unlock failure, besides USER_LOCK_IN_TEARDOWN,
USER_LOCK_BUSY is also required to be cleared. Even though spin lock is
released in between, but USER_LOCK_IN_TEARDOWN is still set, for
USER_LOCK_BUSY, if before every place that waits on this flag,
USER_LOCK_IN_TEARDOWN is checked to bail out, that will make sure no flow
waits on the busy flag set by user_dlm_destroy_lock(), then we can
simplely revert USER_LOCK_BUSY when ocfs2_dlm_unlock fails. Fix
user_dlm_cluster_lock() which is the only function not following this.
[ 941.336392] (python,26174,16):dlmfs_unlink:562 ERROR: unlink
004fb0000060000b5a90b8c847b72e1, error -16 from destroy
[ 989.757536] ------------[ cut here ]------------
[ 989.757709] kernel BUG at fs/ocfs2/dlmfs/userdlm.c:173!
[ 989.757876] invalid opcode: 0000 [#1] SMP
[ 989.758027] Modules linked in: ksplice_2zhuk2jr_ib_ipoib_new(O)
ksplice_2zhuk2jr(O) mptctl mptbase xen_netback xen_blkback xen_gntalloc
xen_gntdev xen_evtchn cdc_ether usbnet mii ocfs2 jbd2 rpcsec_gss_krb5
auth_rpcgss nfsv4 nfsv3 nfs_acl nfs fscache lockd grace ocfs2_dlmfs
ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs bnx2fc
fcoe libfcoe libfc scsi_transport_fc sunrpc ipmi_devintf bridge stp llc
rds_rdma rds bonding ib_sdp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad
rdma_cm ib_cm iw_cm falcon_lsm_serviceable(PE) falcon_nf_netcontain(PE)
mlx4_vnic falcon_kal(E) falcon_lsm_pinned_13402(E) mlx4_ib ib_sa ib_mad
ib_core ib_addr xenfs xen_privcmd dm_multipath iTCO_wdt iTCO_vendor_support
pcspkr sb_edac edac_core i2c_i801 lpc_ich mfd_core ipmi_ssif i2c_core ipmi_si
ipmi_msghandler
[ 989.760686] ioatdma sg ext3 jbd mbcache sd_mod ahci libahci ixgbe dca ptp
pps_core vxlan udp_tunnel ip6_udp_tunnel megaraid_sas mlx4_core crc32c_intel
be2iscsi bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi ipv6 cxgb3 mdio
libiscsi_tcp qla4xxx iscsi_boot_sysfs libiscsi scsi_transport_iscsi wmi
dm_mirror dm_region_hash dm_log dm_mod [last unloaded:
ksplice_2zhuk2jr_ib_ipoib_old]
[ 989.761987] CPU: 10 PID: 19102 Comm: dlm_thread Tainted: P OE
4.1.12-124.57.1.el6uek.x86_64 #2
[ 989.762290] Hardware name: Oracle Corporation ORACLE SERVER
X5-2/ASM,MOTHERBOARD,1U, BIOS 30350100 06/17/2021
[ 989.762599] task: ffff880178af6200 ti: ffff88017f7c8000 task.ti:
ffff88017f7c8000
[ 989.762848] RIP: e030:[<ffffffffc07d4316>] [<ffffffffc07d4316>]
__user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs]
[ 989.763185] RSP: e02b:ffff88017f7cbcb8 EFLAGS: 00010246
[ 989.763353] RAX: 0000000000000000 RBX: ffff880174d48008 RCX:
0000000000000003
[ 989.763565] RDX: 0000000000120012 RSI: 0000000000000003 RDI:
ffff880174d48170
[ 989.763778] RBP: ffff88017f7cbcc8 R08: ffff88021f4293b0 R09:
0000000000000000
[ 989.763991] R10: ffff880179c8c000 R11: 0000000000000003 R12:
ffff880174d48008
[ 989.764204] R13: 0000000000000003 R14: ffff880179c8c000 R15:
ffff88021db7a000
[ 989.764422] FS: 0000000000000000(0000) GS:ffff880247480000(0000)
knlGS:ffff880247480000
[ 989.764685] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 989.764865] CR2: ffff8000007f6800 CR3: 0000000001ae0000 CR4:
0000000000042660
[ 989.765081] Stack:
[ 989.765167] 00000000000
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix sleeping function called from invalid context on RT kernel
When setting bootparams="trace_event=initcall:initcall_start tp_printk=1" in the
cmdline, the output_printk() was called, and the spin_lock_irqsave() was called in the
atomic and irq disable interrupt context suitation. On the PREEMPT_RT kernel,
these locks are replaced with sleepable rt-spinlock, so the stack calltrace will
be triggered.
Fix it by raw_spin_lock_irqsave when PREEMPT_RT and "trace_event=initcall:initcall_start
tp_printk=1" enabled.
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
RCU nest depth: 0, expected: 0
Preemption disabled at:
[<ffffffff8992303e>] try_to_wake_up+0x7e/0xba0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt17+ #19 34c5812404187a875f32bee7977f7367f9679ea7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x60/0x8c
dump_stack+0x10/0x12
__might_resched.cold+0x11d/0x155
rt_spin_lock+0x40/0x70
trace_event_buffer_commit+0x2fa/0x4c0
? map_vsyscall+0x93/0x93
trace_event_raw_event_initcall_start+0xbe/0x110
? perf_trace_initcall_finish+0x210/0x210
? probe_sched_wakeup+0x34/0x40
? ttwu_do_wakeup+0xda/0x310
? trace_hardirqs_on+0x35/0x170
? map_vsyscall+0x93/0x93
do_one_initcall+0x217/0x3c0
? trace_event_raw_event_initcall_level+0x170/0x170
? push_cpu_stop+0x400/0x400
? cblist_init_generic+0x241/0x290
kernel_init_freeable+0x1ac/0x347
? _raw_spin_unlock_irq+0x65/0x80
? rest_init+0xf0/0xf0
kernel_init+0x1e/0x150
ret_from_fork+0x22/0x30
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
iommu/arm-smmu: fix possible null-ptr-deref in arm_smmu_device_probe()
It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.