In the Linux kernel, the following vulnerability has been resolved: block: Fix wrong offset in bio_truncate() bio_truncate() clears the buffer outside of last block of bdev, however current bio_truncate() is using the wrong offset of page. So it can return the uninitialized data. This happened when both of truncated/corrupted FS and userspace (via bdev) are trying to read the last of bdev.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix handling of wrong devices during bond netevent Current implementation of bond netevent handler only check if the handled netdev is VF representor and it missing a check if the VF representor is on the same phys device of the bond handling the netevent. Fix by adding the missing check and optimizing the check if the netdev is VF representor so it will not access uninitialized private data and crashes. BUG: kernel NULL pointer dereference, address: 000000000000036c PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI Workqueue: eth3bond0 bond_mii_monitor [bonding] RIP: 0010:mlx5e_is_uplink_rep+0xc/0x50 [mlx5_core] RSP: 0018:ffff88812d69fd60 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8881cf800000 RCX: 0000000000000000 RDX: ffff88812d69fe10 RSI: 000000000000001b RDI: ffff8881cf800880 RBP: ffff8881cf800000 R08: 00000445cabccf2b R09: 0000000000000008 R10: 0000000000000004 R11: 0000000000000008 R12: ffff88812d69fe10 R13: 00000000fffffffe R14: ffff88820c0f9000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88846fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000036c CR3: 0000000103d80006 CR4: 0000000000370ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mlx5e_eswitch_uplink_rep+0x31/0x40 [mlx5_core] mlx5e_rep_is_lag_netdev+0x94/0xc0 [mlx5_core] mlx5e_rep_esw_bond_netevent+0xeb/0x3d0 [mlx5_core] raw_notifier_call_chain+0x41/0x60 call_netdevice_notifiers_info+0x34/0x80 netdev_lower_state_changed+0x4e/0xa0 bond_mii_monitor+0x56b/0x640 [bonding] process_one_work+0x1b9/0x390 worker_thread+0x4d/0x3d0 ? rescuer_thread+0x350/0x350 kthread+0x124/0x150 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x1f/0x30

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Use del_timer_sync in fw reset flow of halting poll Substitute del_timer() with del_timer_sync() in fw reset polling deactivation flow, in order to prevent a race condition which occurs when del_timer() is called and timer is deactivated while another process is handling the timer interrupt. A situation that led to the following call trace: RIP: 0010:run_timer_softirq+0x137/0x420 <IRQ> recalibrate_cpu_khz+0x10/0x10 ktime_get+0x3e/0xa0 ? sched_clock_cpu+0xb/0xc0 __do_softirq+0xf5/0x2ea irq_exit_rcu+0xc1/0xf0 sysvec_apic_timer_interrupt+0x9e/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 </IRQ>

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Avoid field-overflowing memcpy() In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. Use flexible arrays instead of zero-element arrays (which look like they are always overflowing) and split the cross-field memcpy() into two halves that can be appropriately bounds-checked by the compiler. We were doing: #define ETH_HLEN 14 #define VLAN_HLEN 4 ... #define MLX5E_XDP_MIN_INLINE (ETH_HLEN + VLAN_HLEN) ... struct mlx5e_tx_wqe *wqe = mlx5_wq_cyc_get_wqe(wq, pi); ... struct mlx5_wqe_eth_seg *eseg = &wqe->eth; struct mlx5_wqe_data_seg *dseg = wqe->data; ... memcpy(eseg->inline_hdr.start, xdptxd->data, MLX5E_XDP_MIN_INLINE); target is wqe->eth.inline_hdr.start (which the compiler sees as being 2 bytes in size), but copying 18, intending to write across start (really vlan_tci, 2 bytes). The remaining 16 bytes get written into wqe->data[0], covering byte_count (4 bytes), lkey (4 bytes), and addr (8 bytes). struct mlx5e_tx_wqe { struct mlx5_wqe_ctrl_seg ctrl; /* 0 16 */ struct mlx5_wqe_eth_seg eth; /* 16 16 */ struct mlx5_wqe_data_seg data[]; /* 32 0 */ /* size: 32, cachelines: 1, members: 3 */ /* last cacheline: 32 bytes */ }; struct mlx5_wqe_eth_seg { u8 swp_outer_l4_offset; /* 0 1 */ u8 swp_outer_l3_offset; /* 1 1 */ u8 swp_inner_l4_offset; /* 2 1 */ u8 swp_inner_l3_offset; /* 3 1 */ u8 cs_flags; /* 4 1 */ u8 swp_flags; /* 5 1 */ __be16 mss; /* 6 2 */ __be32 flow_table_metadata; /* 8 4 */ union { struct { __be16 sz; /* 12 2 */ u8 start[2]; /* 14 2 */ } inline_hdr; /* 12 4 */ struct { __be16 type; /* 12 2 */ __be16 vlan_tci; /* 14 2 */ } insert; /* 12 4 */ __be32 trailer; /* 12 4 */ }; /* 12 4 */ /* size: 16, cachelines: 1, members: 9 */ /* last cacheline: 16 bytes */ }; struct mlx5_wqe_data_seg { __be32 byte_count; /* 0 4 */ __be32 lkey; /* 4 4 */ __be64 addr; /* 8 8 */ /* size: 16, cachelines: 1, members: 3 */ /* last cacheline: 16 bytes */ }; So, split the memcpy() so the compiler can reason about the buffer sizes. "pahole" shows no size nor member offset changes to struct mlx5e_tx_wqe nor struct mlx5e_umr_wqe. "objdump -d" shows no meaningful object code changes (i.e. only source line number induced differences and optimizations).

In the Linux kernel, the following vulnerability has been resolved: net: amd-xgbe: Fix skb data length underflow There will be BUG_ON() triggered in include/linux/skbuff.h leading to intermittent kernel panic, when the skb length underflow is detected. Fix this by dropping the packet if such length underflows are seen because of inconsistencies in the hardware descriptors.

In the Linux kernel, the following vulnerability has been resolved: rtnetlink: make sure to refresh master_dev/m_ops in __rtnl_newlink() While looking at one unrelated syzbot bug, I found the replay logic in __rtnl_newlink() to potentially trigger use-after-free. It is better to clear master_dev and m_ops inside the loop, in case we have to replay it.

In the Linux kernel, the following vulnerability has been resolved: ovl: fix NULL pointer dereference in copy up warning This patch is fixing a NULL pointer dereference to get a recently introduced warning message working.

In the Linux kernel, the following vulnerability has been resolved: selinux: fix double free of cond_list on error paths On error path from cond_read_list() and duplicate_policydb_cond_list() the cond_list_destroy() gets called a second time in caller functions, resulting in NULL pointer deref. Fix this by resetting the cond_list_len to 0 in cond_list_destroy(), making subsequent calls a noop. Also consistently reset the cond_list pointer to NULL after freeing. [PM: fix line lengths in the description]

In the Linux kernel, the following vulnerability has been resolved: ASoC: hdmi-codec: Fix OOB memory accesses Correct size of iec_status array by changing it to the size of status array of the struct snd_aes_iec958. This fixes out-of-bounds slab read accesses made by memcpy() of the hdmi-codec driver. This problem is reported by KASAN.

In the Linux kernel, the following vulnerability has been resolved: ASoC: ops: Reject out of bounds values in snd_soc_put_volsw() We don't currently validate that the values being set are within the range we advertised to userspace as being valid, do so and reject any values that are out of range.

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: Fix UAF of leds class devs at unbinding The LED class devices that are created by HD-audio codec drivers are registered via devm_led_classdev_register() and associated with the HD-audio codec device. Unfortunately, it turned out that the devres release doesn't work for this case; namely, since the codec resource release happens before the devm call chain, it triggers a NULL dereference or a UAF for a stale set_brightness_delay callback. For fixing the bug, this patch changes the LED class device register and unregister in a manual manner without devres, keeping the instances in hda_gen_spec.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix deadlock between quota disable and qgroup rescan worker Quota disable ioctl starts a transaction before waiting for the qgroup rescan worker completes. However, this wait can be infinite and results in deadlock because of circular dependency among the quota disable ioctl, the qgroup rescan worker and the other task with transaction such as block group relocation task. The deadlock happens with the steps following: 1) Task A calls ioctl to disable quota. It starts a transaction and waits for qgroup rescan worker completes. 2) Task B such as block group relocation task starts a transaction and joins to the transaction that task A started. Then task B commits to the transaction. In this commit, task B waits for a commit by task A. 3) Task C as the qgroup rescan worker starts its job and starts a transaction. In this transaction start, task C waits for completion of the transaction that task A started and task B committed. This deadlock was found with fstests test case btrfs/115 and a zoned null_blk device. The test case enables and disables quota, and the block group reclaim was triggered during the quota disable by chance. The deadlock was also observed by running quota enable and disable in parallel with 'btrfs balance' command on regular null_blk devices. An example report of the deadlock: [372.469894] INFO: task kworker/u16:6:103 blocked for more than 122 seconds. [372.479944] Not tainted 5.16.0-rc8 #7 [372.485067] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.493898] task:kworker/u16:6 state:D stack: 0 pid: 103 ppid: 2 flags:0x00004000 [372.503285] Workqueue: btrfs-qgroup-rescan btrfs_work_helper [btrfs] [372.510782] Call Trace: [372.514092] <TASK> [372.521684] __schedule+0xb56/0x4850 [372.530104] ? io_schedule_timeout+0x190/0x190 [372.538842] ? lockdep_hardirqs_on+0x7e/0x100 [372.547092] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.555591] schedule+0xe0/0x270 [372.561894] btrfs_commit_transaction+0x18bb/0x2610 [btrfs] [372.570506] ? btrfs_apply_pending_changes+0x50/0x50 [btrfs] [372.578875] ? free_unref_page+0x3f2/0x650 [372.585484] ? finish_wait+0x270/0x270 [372.591594] ? release_extent_buffer+0x224/0x420 [btrfs] [372.599264] btrfs_qgroup_rescan_worker+0xc13/0x10c0 [btrfs] [372.607157] ? lock_release+0x3a9/0x6d0 [372.613054] ? btrfs_qgroup_account_extent+0xda0/0xda0 [btrfs] [372.620960] ? do_raw_spin_lock+0x11e/0x250 [372.627137] ? rwlock_bug.part.0+0x90/0x90 [372.633215] ? lock_is_held_type+0xe4/0x140 [372.639404] btrfs_work_helper+0x1ae/0xa90 [btrfs] [372.646268] process_one_work+0x7e9/0x1320 [372.652321] ? lock_release+0x6d0/0x6d0 [372.658081] ? pwq_dec_nr_in_flight+0x230/0x230 [372.664513] ? rwlock_bug.part.0+0x90/0x90 [372.670529] worker_thread+0x59e/0xf90 [372.676172] ? process_one_work+0x1320/0x1320 [372.682440] kthread+0x3b9/0x490 [372.687550] ? _raw_spin_unlock_irq+0x24/0x50 [372.693811] ? set_kthread_struct+0x100/0x100 [372.700052] ret_from_fork+0x22/0x30 [372.705517] </TASK> [372.709747] INFO: task btrfs-transacti:2347 blocked for more than 123 seconds. [372.729827] Not tainted 5.16.0-rc8 #7 [372.745907] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.767106] task:btrfs-transacti state:D stack: 0 pid: 2347 ppid: 2 flags:0x00004000 [372.787776] Call Trace: [372.801652] <TASK> [372.812961] __schedule+0xb56/0x4850 [372.830011] ? io_schedule_timeout+0x190/0x190 [372.852547] ? lockdep_hardirqs_on+0x7e/0x100 [372.871761] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.886792] schedule+0xe0/0x270 [372.901685] wait_current_trans+0x22c/0x310 [btrfs] [372.919743] ? btrfs_put_transaction+0x3d0/0x3d0 [btrfs] [372.938923] ? finish_wait+0x270/0x270 [372.959085] ? join_transaction+0xc7 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free after failure to create a snapshot At ioctl.c:create_snapshot(), we allocate a pending snapshot structure and then attach it to the transaction's list of pending snapshots. After that we call btrfs_commit_transaction(), and if that returns an error we jump to 'fail' label, where we kfree() the pending snapshot structure. This can result in a later use-after-free of the pending snapshot: 1) We allocated the pending snapshot and added it to the transaction's list of pending snapshots; 2) We call btrfs_commit_transaction(), and it fails either at the first call to btrfs_run_delayed_refs() or btrfs_start_dirty_block_groups(). In both cases, we don't abort the transaction and we release our transaction handle. We jump to the 'fail' label and free the pending snapshot structure. We return with the pending snapshot still in the transaction's list; 3) Another task commits the transaction. This time there's no error at all, and then during the transaction commit it accesses a pointer to the pending snapshot structure that the snapshot creation task has already freed, resulting in a user-after-free. This issue could actually be detected by smatch, which produced the following warning: fs/btrfs/ioctl.c:843 create_snapshot() warn: '&pending_snapshot->list' not removed from list So fix this by not having the snapshot creation ioctl directly add the pending snapshot to the transaction's list. Instead add the pending snapshot to the transaction handle, and then at btrfs_commit_transaction() we add the snapshot to the list only when we can guarantee that any error returned after that point will result in a transaction abort, in which case the ioctl code can safely free the pending snapshot and no one can access it anymore.

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix off by one in BIOS boundary checking Bounds checking when parsing init scripts embedded in the BIOS reject access to the last byte. This causes driver initialization to fail on Apple eMac's with GeForce 2 MX GPUs, leaving the system with no working console. This is probably only seen on OpenFirmware machines like PowerPC Macs because the BIOS image provided by OF is only the used parts of the ROM, not a power-of-two blocks read from PCI directly so PCs always have empty bytes at the end that are never accessed.

In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid scanning potential huge holes When using devm_request_free_mem_region() and devm_memremap_pages() to add ZONE_DEVICE memory, if requested free mem region's end pfn were huge(e.g., 0x400000000), the node_end_pfn() will be also huge (see move_pfn_range_to_zone()). Thus it creates a huge hole between node_start_pfn() and node_end_pfn(). We found on some AMD APUs, amdkfd requested such a free mem region and created a huge hole. In such a case, following code snippet was just doing busy test_bit() looping on the huge hole. for (pfn = start_pfn; pfn < end_pfn; pfn++) { struct page *page = pfn_to_online_page(pfn); if (!page) continue; ... } So we got a soft lockup: watchdog: BUG: soft lockup - CPU#6 stuck for 26s! [bash:1221] CPU: 6 PID: 1221 Comm: bash Not tainted 5.15.0-custom #1 RIP: 0010:pfn_to_online_page+0x5/0xd0 Call Trace: ? kmemleak_scan+0x16a/0x440 kmemleak_write+0x306/0x3a0 ? common_file_perm+0x72/0x170 full_proxy_write+0x5c/0x90 vfs_write+0xb9/0x260 ksys_write+0x67/0xe0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae I did some tests with the patch. (1) amdgpu module unloaded before the patch: real 0m0.976s user 0m0.000s sys 0m0.968s after the patch: real 0m0.981s user 0m0.000s sys 0m0.973s (2) amdgpu module loaded before the patch: real 0m35.365s user 0m0.000s sys 0m35.354s after the patch: real 0m1.049s user 0m0.000s sys 0m1.042s

In the Linux kernel, the following vulnerability has been resolved: dma-buf: heaps: Fix potential spectre v1 gadget It appears like nr could be a Spectre v1 gadget as it's supplied by a user and used as an array index. Prevent the contents of kernel memory from being leaked to userspace via speculative execution by using array_index_nospec. [sumits: added fixes and cc: stable tags]

In the Linux kernel, the following vulnerability has been resolved: IB/hfi1: Fix panic with larger ipoib send_queue_size When the ipoib send_queue_size is increased from the default the following panic happens: RIP: 0010:hfi1_ipoib_drain_tx_ring+0x45/0xf0 [hfi1] Code: 31 e4 eb 0f 8b 85 c8 02 00 00 41 83 c4 01 44 39 e0 76 60 8b 8d cc 02 00 00 44 89 e3 be 01 00 00 00 d3 e3 48 03 9d c0 02 00 00 <c7> 83 18 01 00 00 00 00 00 00 48 8b bb 30 01 00 00 e8 25 af a7 e0 RSP: 0018:ffffc9000798f4a0 EFLAGS: 00010286 RAX: 0000000000008000 RBX: ffffc9000aa0f000 RCX: 000000000000000f RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff88810ff08000 R08: ffff88889476d900 R09: 0000000000000101 R10: 0000000000000000 R11: ffffc90006590ff8 R12: 0000000000000200 R13: ffffc9000798fba8 R14: 0000000000000000 R15: 0000000000000001 FS: 00007fd0f79cc3c0(0000) GS:ffff88885fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc9000aa0f118 CR3: 0000000889c84001 CR4: 00000000001706e0 Call Trace: <TASK> hfi1_ipoib_napi_tx_disable+0x45/0x60 [hfi1] hfi1_ipoib_dev_stop+0x18/0x80 [hfi1] ipoib_ib_dev_stop+0x1d/0x40 [ib_ipoib] ipoib_stop+0x48/0xc0 [ib_ipoib] __dev_close_many+0x9e/0x110 __dev_change_flags+0xd9/0x210 dev_change_flags+0x21/0x60 do_setlink+0x31c/0x10f0 ? __nla_validate_parse+0x12d/0x1a0 ? __nla_parse+0x21/0x30 ? inet6_validate_link_af+0x5e/0xf0 ? cpumask_next+0x1f/0x20 ? __snmp6_fill_stats64.isra.53+0xbb/0x140 ? __nla_validate_parse+0x47/0x1a0 __rtnl_newlink+0x530/0x910 ? pskb_expand_head+0x73/0x300 ? __kmalloc_node_track_caller+0x109/0x280 ? __nla_put+0xc/0x20 ? cpumask_next_and+0x20/0x30 ? update_sd_lb_stats.constprop.144+0xd3/0x820 ? _raw_spin_unlock_irqrestore+0x25/0x37 ? __wake_up_common_lock+0x87/0xc0 ? kmem_cache_alloc_trace+0x3d/0x3d0 rtnl_newlink+0x43/0x60 The issue happens when the shift that should have been a function of the txq item size mistakenly used the ring size. Fix by using the item size.

In the Linux kernel, the following vulnerability has been resolved: IB/hfi1: Fix AIP early init panic An early failure in hfi1_ipoib_setup_rn() can lead to the following panic: BUG: unable to handle kernel NULL pointer dereference at 00000000000001b0 PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI Workqueue: events work_for_cpu_fn RIP: 0010:try_to_grab_pending+0x2b/0x140 Code: 1f 44 00 00 41 55 41 54 55 48 89 d5 53 48 89 fb 9c 58 0f 1f 44 00 00 48 89 c2 fa 66 0f 1f 44 00 00 48 89 55 00 40 84 f6 75 77 <f0> 48 0f ba 2b 00 72 09 31 c0 5b 5d 41 5c 41 5d c3 48 89 df e8 6c RSP: 0018:ffffb6b3cf7cfa48 EFLAGS: 00010046 RAX: 0000000000000246 RBX: 00000000000001b0 RCX: 0000000000000000 RDX: 0000000000000246 RSI: 0000000000000000 RDI: 00000000000001b0 RBP: ffffb6b3cf7cfa70 R08: 0000000000000f09 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffffb6b3cf7cfa90 R14: ffffffff9b2fbfc0 R15: ffff8a4fdf244690 FS: 0000000000000000(0000) GS:ffff8a527f400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000001b0 CR3: 00000017e2410003 CR4: 00000000007706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: __cancel_work_timer+0x42/0x190 ? dev_printk_emit+0x4e/0x70 iowait_cancel_work+0x15/0x30 [hfi1] hfi1_ipoib_txreq_deinit+0x5a/0x220 [hfi1] ? dev_err+0x6c/0x90 hfi1_ipoib_netdev_dtor+0x15/0x30 [hfi1] hfi1_ipoib_setup_rn+0x10e/0x150 [hfi1] rdma_init_netdev+0x5a/0x80 [ib_core] ? hfi1_ipoib_free_rdma_netdev+0x20/0x20 [hfi1] ipoib_intf_init+0x6c/0x350 [ib_ipoib] ipoib_intf_alloc+0x5c/0xc0 [ib_ipoib] ipoib_add_one+0xbe/0x300 [ib_ipoib] add_client_context+0x12c/0x1a0 [ib_core] enable_device_and_get+0xdc/0x1d0 [ib_core] ib_register_device+0x572/0x6b0 [ib_core] rvt_register_device+0x11b/0x220 [rdmavt] hfi1_register_ib_device+0x6b4/0x770 [hfi1] do_init_one.isra.20+0x3e3/0x680 [hfi1] local_pci_probe+0x41/0x90 work_for_cpu_fn+0x16/0x20 process_one_work+0x1a7/0x360 ? create_worker+0x1a0/0x1a0 worker_thread+0x1cf/0x390 ? create_worker+0x1a0/0x1a0 kthread+0x116/0x130 ? kthread_flush_work_fn+0x10/0x10 ret_from_fork+0x1f/0x40 The panic happens in hfi1_ipoib_txreq_deinit() because there is a NULL deref when hfi1_ipoib_netdev_dtor() is called in this error case. hfi1_ipoib_txreq_init() and hfi1_ipoib_rxq_init() are self unwinding so fix by adjusting the error paths accordingly. Other changes: - hfi1_ipoib_free_rdma_netdev() is deleted including the free_netdev() since the netdev core code deletes calls free_netdev() - The switch to the accelerated entrances is moved to the success path.

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Avoid consuming a stale esr value when SError occur When any exception other than an IRQ occurs, the CPU updates the ESR_EL2 register with the exception syndrome. An SError may also become pending, and will be synchronised by KVM. KVM notes the exception type, and whether an SError was synchronised in exit_code. When an exception other than an IRQ occurs, fixup_guest_exit() updates vcpu->arch.fault.esr_el2 from the hardware register. When an SError was synchronised, the vcpu esr value is used to determine if the exception was due to an HVC. If so, ELR_EL2 is moved back one instruction. This is so that KVM can process the SError first, and re-execute the HVC if the guest survives the SError. But if an IRQ synchronises an SError, the vcpu's esr value is stale. If the previous non-IRQ exception was an HVC, KVM will corrupt ELR_EL2, causing an unrelated guest instruction to be executed twice. Check ARM_EXCEPTION_CODE() before messing with ELR_EL2, IRQs don't update this register so don't need to check.

In the Linux kernel, the following vulnerability has been resolved: RDMA/ucma: Protect mc during concurrent multicast leaves Partially revert the commit mentioned in the Fixes line to make sure that allocation and erasing multicast struct are locked. BUG: KASAN: use-after-free in ucma_cleanup_multicast drivers/infiniband/core/ucma.c:491 [inline] BUG: KASAN: use-after-free in ucma_destroy_private_ctx+0x914/0xb70 drivers/infiniband/core/ucma.c:579 Read of size 8 at addr ffff88801bb74b00 by task syz-executor.1/25529 CPU: 0 PID: 25529 Comm: syz-executor.1 Not tainted 5.16.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __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/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 ucma_cleanup_multicast drivers/infiniband/core/ucma.c:491 [inline] ucma_destroy_private_ctx+0x914/0xb70 drivers/infiniband/core/ucma.c:579 ucma_destroy_id+0x1e6/0x280 drivers/infiniband/core/ucma.c:614 ucma_write+0x25c/0x350 drivers/infiniband/core/ucma.c:1732 vfs_write+0x28e/0xae0 fs/read_write.c:588 ksys_write+0x1ee/0x250 fs/read_write.c:643 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 Currently the xarray search can touch a concurrently freeing mc as the xa_for_each() is not surrounded by any lock. Rather than hold the lock for a full scan hold it only for the effected items, which is usually an empty list.