In the Linux kernel, the following vulnerability has been resolved: ieee802154: ca8210: Fix a potential UAF in ca8210_probe If of_clk_add_provider() fails in ca8210_register_ext_clock(), it calls clk_unregister() to release priv->clk and returns an error. However, the caller ca8210_probe() then calls ca8210_remove(), where priv->clk is freed again in ca8210_unregister_ext_clock(). In this case, a use-after-free may happen in the second time we call clk_unregister(). Fix this by removing the first clk_unregister(). Also, priv->clk could be an error code on failure of clk_register_fixed_rate(). Use IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().

In the Linux kernel, the following vulnerability has been resolved: ravb: Fix use-after-free issue in ravb_tx_timeout_work() The ravb_stop() should call cancel_work_sync(). Otherwise, ravb_tx_timeout_work() is possible to use the freed priv after ravb_remove() was called like below: CPU0 CPU1 ravb_tx_timeout() ravb_remove() unregister_netdev() free_netdev(ndev) // free priv ravb_tx_timeout_work() // use priv unregister_netdev() will call .ndo_stop() so that ravb_stop() is called. And, after phy_stop() is called, netif_carrier_off() is also called. So that .ndo_tx_timeout() will not be called after phy_stop().

In the Linux kernel, the following vulnerability has been resolved: nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid() The nvme_fc_fcp_op structure describing an AEN operation is initialized with a null request structure pointer. An FC LLDD may make a call to nvme_fc_io_getuuid passing a pointer to an nvmefc_fcp_req for an AEN operation. Add validation of the request structure pointer before dereference.

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: assert requested protocol is valid The protocol is used in a bit mask to determine if the protocol is supported. Assert the provided protocol is less than the maximum defined so it doesn't potentially perform a shift-out-of-bounds and provide a clearer error for undefined protocols vs unsupported ones.

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Set all reserved memblocks on Node#0 at initialization After commit 61167ad5fecdea ("mm: pass nid to reserve_bootmem_region()") we get a panic if DEFERRED_STRUCT_PAGE_INIT is enabled: [ 0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000000000002b82, era == 90000000040e3f28, ra == 90000000040e3f18 [ 0.000000] Oops[#1]: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.5.0+ #733 [ 0.000000] pc 90000000040e3f28 ra 90000000040e3f18 tp 90000000046f4000 sp 90000000046f7c90 [ 0.000000] a0 0000000000000001 a1 0000000000200000 a2 0000000000000040 a3 90000000046f7ca0 [ 0.000000] a4 90000000046f7ca4 a5 0000000000000000 a6 90000000046f7c38 a7 0000000000000000 [ 0.000000] t0 0000000000000002 t1 9000000004b00ac8 t2 90000000040e3f18 t3 90000000040f0800 [ 0.000000] t4 00000000000f0000 t5 80000000ffffe07e t6 0000000000000003 t7 900000047fff5e20 [ 0.000000] t8 aaaaaaaaaaaaaaab u0 0000000000000018 s9 0000000000000000 s0 fffffefffe000000 [ 0.000000] s1 0000000000000000 s2 0000000000000080 s3 0000000000000040 s4 0000000000000000 [ 0.000000] s5 0000000000000000 s6 fffffefffe000000 s7 900000000470b740 s8 9000000004ad4000 [ 0.000000] ra: 90000000040e3f18 reserve_bootmem_region+0xec/0x21c [ 0.000000] ERA: 90000000040e3f28 reserve_bootmem_region+0xfc/0x21c [ 0.000000] CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) [ 0.000000] PRMD: 00000000 (PPLV0 -PIE -PWE) [ 0.000000] EUEN: 00000000 (-FPE -SXE -ASXE -BTE) [ 0.000000] ECFG: 00070800 (LIE=11 VS=7) [ 0.000000] ESTAT: 00010800 [PIL] (IS=11 ECode=1 EsubCode=0) [ 0.000000] BADV: 0000000000002b82 [ 0.000000] PRID: 0014d000 (Loongson-64bit, Loongson-3A6000) [ 0.000000] Modules linked in: [ 0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____)) [ 0.000000] Stack : 0000000000000000 9000000002eb5430 0000003a00000020 90000000045ccd00 [ 0.000000] 900000000470e000 90000000002c1918 0000000000000000 9000000004110780 [ 0.000000] 00000000fe6c0000 0000000480000000 9000000004b4e368 9000000004110748 [ 0.000000] 0000000000000000 900000000421ca84 9000000004620000 9000000004564970 [ 0.000000] 90000000046f7d78 9000000002cc9f70 90000000002c1918 900000000470e000 [ 0.000000] 9000000004564970 90000000040bc0e0 90000000046f7d78 0000000000000000 [ 0.000000] 0000000000004000 90000000045ccd00 0000000000000000 90000000002c1918 [ 0.000000] 90000000002c1900 900000000470b700 9000000004b4df78 9000000004620000 [ 0.000000] 90000000046200a8 90000000046200a8 0000000000000000 9000000004218b2c [ 0.000000] 9000000004270008 0000000000000001 0000000000000000 90000000045ccd00 [ 0.000000] ... [ 0.000000] Call Trace: [ 0.000000] [<90000000040e3f28>] reserve_bootmem_region+0xfc/0x21c [ 0.000000] [<900000000421ca84>] memblock_free_all+0x114/0x350 [ 0.000000] [<9000000004218b2c>] mm_core_init+0x138/0x3cc [ 0.000000] [<9000000004200e38>] start_kernel+0x488/0x7a4 [ 0.000000] [<90000000040df0d8>] kernel_entry+0xd8/0xdc [ 0.000000] [ 0.000000] Code: 02eb21ad 00410f4c 380c31ac <262b818d> 6800b70d 02c1c196 0015001c 57fe4bb1 260002cd The reason is early memblock_reserve() in memblock_init() set node id to MAX_NUMNODES, making NODE_DATA(nid) a NULL dereference in the call chain reserve_bootmem_region() -> init_reserved_page(). After memblock_init(), those late calls of memblock_reserve() operate on subregions of memblock .memory regions. As a result, these reserved regions will be set to the correct node at the first iteration of memmap_init_reserved_pages(). So set all reserved memblocks on Node#0 at initialization can avoid this panic.

In the Linux kernel, the following vulnerability has been resolved: x86/alternatives: Disable KASAN in apply_alternatives() Fei has reported that KASAN triggers during apply_alternatives() on a 5-level paging machine: BUG: KASAN: out-of-bounds in rcu_is_watching() Read of size 4 at addr ff110003ee6419a0 by task swapper/0/0 ... __asan_load4() rcu_is_watching() trace_hardirqs_on() text_poke_early() apply_alternatives() ... On machines with 5-level paging, cpu_feature_enabled(X86_FEATURE_LA57) gets patched. It includes KASAN code, where KASAN_SHADOW_START depends on __VIRTUAL_MASK_SHIFT, which is defined with cpu_feature_enabled(). KASAN gets confused when apply_alternatives() patches the KASAN_SHADOW_START users. A test patch that makes KASAN_SHADOW_START static, by replacing __VIRTUAL_MASK_SHIFT with 56, works around the issue. Fix it for real by disabling KASAN while the kernel is patching alternatives. [ mingo: updated the changelog ]

In the Linux kernel, the following vulnerability has been resolved: tee: amdtee: fix use-after-free vulnerability in amdtee_close_session There is a potential race condition in amdtee_close_session that may cause use-after-free in amdtee_open_session. For instance, if a session has refcount == 1, and one thread tries to free this session via: kref_put(&sess->refcount, destroy_session); the reference count will get decremented, and the next step would be to call destroy_session(). However, if in another thread, amdtee_open_session() is called before destroy_session() has completed execution, alloc_session() may return 'sess' that will be freed up later in destroy_session() leading to use-after-free in amdtee_open_session. To fix this issue, treat decrement of sess->refcount and removal of 'sess' from session list in destroy_session() as a critical section, so that it is executed atomically.

In the Linux kernel, the following vulnerability has been resolved: net: nfc: fix races in nfc_llcp_sock_get() and nfc_llcp_sock_get_sn() Sili Luo reported a race in nfc_llcp_sock_get(), leading to UAF. Getting a reference on the socket found in a lookup while holding a lock should happen before releasing the lock. nfc_llcp_sock_get_sn() has a similar problem. Finally nfc_llcp_recv_snl() needs to make sure the socket found by nfc_llcp_sock_from_sn() does not disappear.

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Do not attempt to read past "commit" When iterating over the ring buffer while the ring buffer is active, the writer can corrupt the reader. There's barriers to help detect this and handle it, but that code missed the case where the last event was at the very end of the page and has only 4 bytes left. The checks to detect the corruption by the writer to reads needs to see the length of the event. If the length in the first 4 bytes is zero then the length is stored in the second 4 bytes. But if the writer is in the process of updating that code, there's a small window where the length in the first 4 bytes could be zero even though the length is only 4 bytes. That will cause rb_event_length() to read the next 4 bytes which could happen to be off the allocated page. To protect against this, fail immediately if the next event pointer is less than 8 bytes from the end of the commit (last byte of data), as all events must be a minimum of 8 bytes anyway.

In the Linux kernel, the following vulnerability has been resolved: scsi: pm80xx: Avoid leaking tags when processing OPC_INB_SET_CONTROLLER_CONFIG command Tags allocated for OPC_INB_SET_CONTROLLER_CONFIG command need to be freed when we receive the response.

In the Linux kernel, the following vulnerability has been resolved: ceph: drop messages from MDS when unmounting When unmounting all the dirty buffers will be flushed and after the last osd request is finished the last reference of the i_count will be released. Then it will flush the dirty cap/snap to MDSs, and the unmounting won't wait the possible acks, which will ihold the inodes when updating the metadata locally but makes no sense any more, of this. This will make the evict_inodes() to skip these inodes. If encrypt is enabled the kernel generate a warning when removing the encrypt keys when the skipped inodes still hold the keyring: WARNING: CPU: 4 PID: 168846 at fs/crypto/keyring.c:242 fscrypt_destroy_keyring+0x7e/0xd0 CPU: 4 PID: 168846 Comm: umount Tainted: G S 6.1.0-rc5-ceph-g72ead199864c #1 Hardware name: Supermicro SYS-5018R-WR/X10SRW-F, BIOS 2.0 12/17/2015 RIP: 0010:fscrypt_destroy_keyring+0x7e/0xd0 RSP: 0018:ffffc9000b277e28 EFLAGS: 00010202 RAX: 0000000000000002 RBX: ffff88810d52ac00 RCX: ffff88810b56aa00 RDX: 0000000080000000 RSI: ffffffff822f3a09 RDI: ffff888108f59000 RBP: ffff8881d394fb88 R08: 0000000000000028 R09: 0000000000000000 R10: 0000000000000001 R11: 11ff4fe6834fcd91 R12: ffff8881d394fc40 R13: ffff888108f59000 R14: ffff8881d394f800 R15: 0000000000000000 FS: 00007fd83f6f1080(0000) GS:ffff88885fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f918d417000 CR3: 000000017f89a005 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> generic_shutdown_super+0x47/0x120 kill_anon_super+0x14/0x30 ceph_kill_sb+0x36/0x90 [ceph] deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x67/0xb0 exit_to_user_mode_prepare+0x23d/0x240 syscall_exit_to_user_mode+0x25/0x60 do_syscall_64+0x40/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd83dc39e9b Later the kernel will crash when iput() the inodes and dereferencing the "sb->s_master_keys", which has been released by the generic_shutdown_super().

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Return CQE error if invalid lkey was supplied RXE is missing update of WQE status in LOCAL_WRITE failures. This caused the following kernel panic if someone sent an atomic operation with an explicitly wrong lkey. [leonro@vm ~]$ mkt test test_atomic_invalid_lkey (tests.test_atomic.AtomicTest) ... WARNING: CPU: 5 PID: 263 at drivers/infiniband/sw/rxe/rxe_comp.c:740 rxe_completer+0x1a6d/0x2e30 [rdma_rxe] Modules linked in: crc32_generic rdma_rxe ip6_udp_tunnel udp_tunnel rdma_ucm rdma_cm ib_umad ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5_core ptp pps_core CPU: 5 PID: 263 Comm: python3 Not tainted 5.13.0-rc1+ #2936 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:rxe_completer+0x1a6d/0x2e30 [rdma_rxe] Code: 03 0f 8e 65 0e 00 00 3b 93 10 06 00 00 0f 84 82 0a 00 00 4c 89 ff 4c 89 44 24 38 e8 2d 74 a9 e1 4c 8b 44 24 38 e9 1c f5 ff ff <0f> 0b e9 0c e8 ff ff b8 05 00 00 00 41 bf 05 00 00 00 e9 ab e7 ff RSP: 0018:ffff8880158af090 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888016a78000 RCX: ffffffffa0cf1652 RDX: 1ffff9200004b442 RSI: 0000000000000004 RDI: ffffc9000025a210 RBP: dffffc0000000000 R08: 00000000ffffffea R09: ffff88801617740b R10: ffffed1002c2ee81 R11: 0000000000000007 R12: ffff88800f3b63e8 R13: ffff888016a78008 R14: ffffc9000025a180 R15: 000000000000000c FS: 00007f88b622a740(0000) GS:ffff88806d540000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88b5a1fa10 CR3: 000000000d848004 CR4: 0000000000370ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rxe_do_task+0x130/0x230 [rdma_rxe] rxe_rcv+0xb11/0x1df0 [rdma_rxe] rxe_loopback+0x157/0x1e0 [rdma_rxe] rxe_responder+0x5532/0x7620 [rdma_rxe] rxe_do_task+0x130/0x230 [rdma_rxe] rxe_rcv+0x9c8/0x1df0 [rdma_rxe] rxe_loopback+0x157/0x1e0 [rdma_rxe] rxe_requester+0x1efd/0x58c0 [rdma_rxe] rxe_do_task+0x130/0x230 [rdma_rxe] rxe_post_send+0x998/0x1860 [rdma_rxe] ib_uverbs_post_send+0xd5f/0x1220 [ib_uverbs] ib_uverbs_write+0x847/0xc80 [ib_uverbs] vfs_write+0x1c5/0x840 ksys_write+0x176/0x1d0 do_syscall_64+0x3f/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: uio_hv_generic: Fix another memory leak in error handling paths Memory allocated by 'vmbus_alloc_ring()' at the beginning of the probe function is never freed in the error handling path. Add the missing 'vmbus_free_ring()' call. Note that it is already freed in the .remove function.

In the Linux kernel, the following vulnerability has been resolved: erofs: fix lz4 inplace decompression Currently EROFS can map another compressed buffer for inplace decompression, that was used to handle the cases that some pages of compressed data are actually not in-place I/O. However, like most simple LZ77 algorithms, LZ4 expects the compressed data is arranged at the end of the decompressed buffer and it explicitly uses memmove() to handle overlapping: __________________________________________________________ |_ direction of decompression --> ____ |_ compressed data _| Although EROFS arranges compressed data like this, it typically maps two individual virtual buffers so the relative order is uncertain. Previously, it was hardly observed since LZ4 only uses memmove() for short overlapped literals and x86/arm64 memmove implementations seem to completely cover it up and they don't have this issue. Juhyung reported that EROFS data corruption can be found on a new Intel x86 processor. After some analysis, it seems that recent x86 processors with the new FSRM feature expose this issue with "rep movsb". Let's strictly use the decompressed buffer for lz4 inplace decompression for now. Later, as an useful improvement, we could try to tie up these two buffers together in the correct order.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Wake DMCUB before sending a command [Why] We can hang in place trying to send commands when the DMCUB isn't powered on. [How] For functions that execute within a DC context or DC lock we can wrap the direct calls to dm_execute_dmub_cmd/list with code that exits idle power optimizations and reallows once we're done with the command submission on success. For DM direct submissions the DM will need to manage the enter/exit sequencing manually. We cannot invoke a DMCUB command directly within the DM execution helper or we can deadlock.

In the Linux kernel, the following vulnerability has been resolved: drm/bridge: sii902x: Fix probing race issue A null pointer dereference crash has been observed rarely on TI platforms using sii9022 bridge: [ 53.271356] sii902x_get_edid+0x34/0x70 [sii902x] [ 53.276066] sii902x_bridge_get_edid+0x14/0x20 [sii902x] [ 53.281381] drm_bridge_get_edid+0x20/0x34 [drm] [ 53.286305] drm_bridge_connector_get_modes+0x8c/0xcc [drm_kms_helper] [ 53.292955] drm_helper_probe_single_connector_modes+0x190/0x538 [drm_kms_helper] [ 53.300510] drm_client_modeset_probe+0x1f0/0xbd4 [drm] [ 53.305958] __drm_fb_helper_initial_config_and_unlock+0x50/0x510 [drm_kms_helper] [ 53.313611] drm_fb_helper_initial_config+0x48/0x58 [drm_kms_helper] [ 53.320039] drm_fbdev_dma_client_hotplug+0x84/0xd4 [drm_dma_helper] [ 53.326401] drm_client_register+0x5c/0xa0 [drm] [ 53.331216] drm_fbdev_dma_setup+0xc8/0x13c [drm_dma_helper] [ 53.336881] tidss_probe+0x128/0x264 [tidss] [ 53.341174] platform_probe+0x68/0xc4 [ 53.344841] really_probe+0x188/0x3c4 [ 53.348501] __driver_probe_device+0x7c/0x16c [ 53.352854] driver_probe_device+0x3c/0x10c [ 53.357033] __device_attach_driver+0xbc/0x158 [ 53.361472] bus_for_each_drv+0x88/0xe8 [ 53.365303] __device_attach+0xa0/0x1b4 [ 53.369135] device_initial_probe+0x14/0x20 [ 53.373314] bus_probe_device+0xb0/0xb4 [ 53.377145] deferred_probe_work_func+0xcc/0x124 [ 53.381757] process_one_work+0x1f0/0x518 [ 53.385770] worker_thread+0x1e8/0x3dc [ 53.389519] kthread+0x11c/0x120 [ 53.392750] ret_from_fork+0x10/0x20 The issue here is as follows: - tidss probes, but is deferred as sii902x is still missing. - sii902x starts probing and enters sii902x_init(). - sii902x calls drm_bridge_add(). Now the sii902x bridge is ready from DRM's perspective. - sii902x calls sii902x_audio_codec_init() and platform_device_register_data() - The registration of the audio platform device causes probing of the deferred devices. - tidss probes, which eventually causes sii902x_bridge_get_edid() to be called. - sii902x_bridge_get_edid() tries to use the i2c to read the edid. However, the sii902x driver has not set up the i2c part yet, leading to the crash. Fix this by moving the drm_bridge_add() to the end of the sii902x_init(), which is also at the very end of sii902x_probe().

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-v3: Fix soft lockup triggered by arm_smmu_mm_invalidate_range When running an SVA case, the following soft lockup is triggered: -------------------------------------------------------------------- watchdog: BUG: soft lockup - CPU#244 stuck for 26s! pstate: 83400009 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : arm_smmu_cmdq_issue_cmdlist+0x178/0xa50 lr : arm_smmu_cmdq_issue_cmdlist+0x150/0xa50 sp : ffff8000d83ef290 x29: ffff8000d83ef290 x28: 000000003b9aca00 x27: 0000000000000000 x26: ffff8000d83ef3c0 x25: da86c0812194a0e8 x24: 0000000000000000 x23: 0000000000000040 x22: ffff8000d83ef340 x21: ffff0000c63980c0 x20: 0000000000000001 x19: ffff0000c6398080 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: ffff3000b4a3bbb0 x14: ffff3000b4a30888 x13: ffff3000b4a3cf60 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : ffffc08120e4d6bc x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000048cfa x5 : 0000000000000000 x4 : 0000000000000001 x3 : 000000000000000a x2 : 0000000080000000 x1 : 0000000000000000 x0 : 0000000000000001 Call trace: arm_smmu_cmdq_issue_cmdlist+0x178/0xa50 __arm_smmu_tlb_inv_range+0x118/0x254 arm_smmu_tlb_inv_range_asid+0x6c/0x130 arm_smmu_mm_invalidate_range+0xa0/0xa4 __mmu_notifier_invalidate_range_end+0x88/0x120 unmap_vmas+0x194/0x1e0 unmap_region+0xb4/0x144 do_mas_align_munmap+0x290/0x490 do_mas_munmap+0xbc/0x124 __vm_munmap+0xa8/0x19c __arm64_sys_munmap+0x28/0x50 invoke_syscall+0x78/0x11c el0_svc_common.constprop.0+0x58/0x1c0 do_el0_svc+0x34/0x60 el0_svc+0x2c/0xd4 el0t_64_sync_handler+0x114/0x140 el0t_64_sync+0x1a4/0x1a8 -------------------------------------------------------------------- Note that since 6.6-rc1 the arm_smmu_mm_invalidate_range above is renamed to "arm_smmu_mm_arch_invalidate_secondary_tlbs", yet the problem remains. The commit 06ff87bae8d3 ("arm64: mm: remove unused functions and variable protoypes") fixed a similar lockup on the CPU MMU side. Yet, it can occur to SMMU too, since arm_smmu_mm_arch_invalidate_secondary_tlbs() is called typically next to MMU tlb flush function, e.g. tlb_flush_mmu_tlbonly { tlb_flush { __flush_tlb_range { // check MAX_TLBI_OPS } } mmu_notifier_arch_invalidate_secondary_tlbs { arm_smmu_mm_arch_invalidate_secondary_tlbs { // does not check MAX_TLBI_OPS } } } Clone a CMDQ_MAX_TLBI_OPS from the MAX_TLBI_OPS in tlbflush.h, since in an SVA case SMMU uses the CPU page table, so it makes sense to align with the tlbflush code. Then, replace per-page TLBI commands with a single per-asid TLBI command, if the request size hits this threshold.

In the Linux kernel, the following vulnerability has been resolved: x86/srso: Add SRSO mitigation for Hygon processors Add mitigation for the speculative return stack overflow vulnerability which exists on Hygon processors too.

In the Linux kernel, the following vulnerability has been resolved: arm64: errata: Add Cortex-A520 speculative unprivileged load workaround Implement the workaround for ARM Cortex-A520 erratum 2966298. On an affected Cortex-A520 core, a speculatively executed unprivileged load might leak data from a privileged load via a cache side channel. The issue only exists for loads within a translation regime with the same translation (e.g. same ASID and VMID). Therefore, the issue only affects the return to EL0. The workaround is to execute a TLBI before returning to EL0 after all loads of privileged data. A non-shareable TLBI to any address is sufficient. The workaround isn't necessary if page table isolation (KPTI) is enabled, but for simplicity it will be. Page table isolation should normally be disabled for Cortex-A520 as it supports the CSV3 feature and the E0PD feature (used when KASLR is enabled).

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix uaf in smb20_oplock_break_ack drop reference after use opinfo.