In the Linux kernel, the following vulnerability has been resolved: mptcp: ensure snd_una is properly initialized on connect This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt is properly initialized on connect"). It turns out that syzkaller can trigger the retransmit after fallback and before processing any other incoming packet - so that snd_una is still left uninitialized. Address the issue explicitly initializing snd_una together with snd_nxt and write_seq.

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: validate HE operation element parsing Validate that the HE operation element has the correct length before parsing it.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mvm: check n_ssids before accessing the ssids In some versions of cfg80211, the ssids poinet might be a valid one even though n_ssids is 0. Accessing the pointer in this case will cuase an out-of-bound access. Fix this by checking n_ssids first.

In the Linux kernel, the following vulnerability has been resolved: net: ethtool: fix the error condition in ethtool_get_phy_stats_ethtool() Clang static checker (scan-build) warning: net/ethtool/ioctl.c:line 2233, column 2 Called function pointer is null (null dereference). Return '-EOPNOTSUPP' when 'ops->get_ethtool_phy_stats' is NULL to fix this typo error.

In the Linux kernel, the following vulnerability has been resolved: xhci: Handle TD clearing for multiple streams case When multiple streams are in use, multiple TDs might be in flight when an endpoint is stopped. We need to issue a Set TR Dequeue Pointer for each, to ensure everything is reset properly and the caches cleared. Change the logic so that any N>1 TDs found active for different streams are deferred until after the first one is processed, calling xhci_invalidate_cancelled_tds() again from xhci_handle_cmd_set_deq() to queue another command until we are done with all of them. Also change the error/"should never happen" paths to ensure we at least clear any affected TDs, even if we can't issue a command to clear the hardware cache, and complain loudly with an xhci_warn() if this ever happens. This problem case dates back to commit e9df17eb1408 ("USB: xhci: Correct assumptions about number of rings per endpoint.") early on in the XHCI driver's life, when stream support was first added. It was then identified but not fixed nor made into a warning in commit 674f8438c121 ("xhci: split handling halted endpoints into two steps"), which added a FIXME comment for the problem case (without materially changing the behavior as far as I can tell, though the new logic made the problem more obvious). Then later, in commit 94f339147fc3 ("xhci: Fix failure to give back some cached cancelled URBs."), it was acknowledged again. [Mathias: commit 94f339147fc3 ("xhci: Fix failure to give back some cached cancelled URBs.") was a targeted regression fix to the previously mentioned patch. Users reported issues with usb stuck after unmounting/disconnecting UAS devices. This rolled back the TD clearing of multiple streams to its original state.] Apparently the commit author was aware of the problem (yet still chose to submit it): It was still mentioned as a FIXME, an xhci_dbg() was added to log the problem condition, and the remaining issue was mentioned in the commit description. The choice of making the log type xhci_dbg() for what is, at this point, a completely unhandled and known broken condition is puzzling and unfortunate, as it guarantees that no actual users would see the log in production, thereby making it nigh undebuggable (indeed, even if you turn on DEBUG, the message doesn't really hint at there being a problem at all). It took me *months* of random xHC crashes to finally find a reliable repro and be able to do a deep dive debug session, which could all have been avoided had this unhandled, broken condition been actually reported with a warning, as it should have been as a bug intentionally left in unfixed (never mind that it shouldn't have been left in at all). > Another fix to solve clearing the caches of all stream rings with > cancelled TDs is needed, but not as urgent. 3 years after that statement and 14 years after the original bug was introduced, I think it's finally time to fix it. And maybe next time let's not leave bugs unfixed (that are actually worse than the original bug), and let's actually get people to review kernel commits please. Fixes xHC crashes and IOMMU faults with UAS devices when handling errors/faults. Easiest repro is to use `hdparm` to mark an early sector (e.g. 1024) on a disk as bad, then `cat /dev/sdX > /dev/null` in a loop. At least in the case of JMicron controllers, the read errors end up having to cancel two TDs (for two queued requests to different streams) and the one that didn't get cleared properly ends up faulting the xHC entirely when it tries to access DMA pages that have since been unmapped, referred to by the stale TDs. This normally happens quickly (after two or three loops). After this fix, I left the `cat` in a loop running overnight and experienced no xHC failures, with all read errors recovered properly. Repro'd and tested on an Apple M1 Mac Mini (dwc3 host). On systems without an IOMMU, this bug would instead silently corrupt freed memory, making this a ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: don't attempt to schedule hpd_work on headless cards If the card doesn't have display hardware, hpd_work and hpd_lock are left uninitialized which causes BUG when attempting to schedule hpd_work on runtime PM resume. Fix it by adding headless flag to DRM and skip any hpd if it's set.

In the Linux kernel, the following vulnerability has been resolved: block: fix request.queuelist usage in flush Friedrich Weber reported a kernel crash problem and bisected to commit 81ada09cc25e ("blk-flush: reuse rq queuelist in flush state machine"). The root cause is that we use "list_move_tail(&rq->queuelist, pending)" in the PREFLUSH/POSTFLUSH sequences. But rq->queuelist.next == xxx since it's popped out from plug->cached_rq in __blk_mq_alloc_requests_batch(). We don't initialize its queuelist just for this first request, although the queuelist of all later popped requests will be initialized. Fix it by changing to use "list_add_tail(&rq->queuelist, pending)" so rq->queuelist doesn't need to be initialized. It should be ok since rq can't be on any list when PREFLUSH or POSTFLUSH, has no move actually. Please note the commit 81ada09cc25e ("blk-flush: reuse rq queuelist in flush state machine") also has another requirement that no drivers would touch rq->queuelist after blk_mq_end_request() since we will reuse it to add rq to the post-flush pending list in POSTFLUSH. If this is not true, we will have to revert that commit IMHO. This updated version adds "list_del_init(&rq->queuelist)" in flush rq callback since the dm layer may submit request of a weird invalid format (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH), which causes double list_add if without this "list_del_init(&rq->queuelist)". The weird invalid format problem should be fixed in dm layer.

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dpt: Make DPT object unshrinkable In some scenarios, the DPT object gets shrunk but the actual framebuffer did not and thus its still there on the DPT's vm->bound_list. Then it tries to rewrite the PTEs via a stale CPU mapping. This causes panic. [vsyrjala: Add TODO comment] (cherry picked from commit 51064d471c53dcc8eddd2333c3f1c1d9131ba36c)

In the Linux kernel, the following vulnerability has been resolved: vmxnet3: disable rx data ring on dma allocation failure When vmxnet3_rq_create() fails to allocate memory for rq->data_ring.base, the subsequent call to vmxnet3_rq_destroy_all_rxdataring does not reset rq->data_ring.desc_size for the data ring that failed, which presumably causes the hypervisor to reference it on packet reception. To fix this bug, rq->data_ring.desc_size needs to be set to 0 to tell the hypervisor to disable this feature. [ 95.436876] kernel BUG at net/core/skbuff.c:207! [ 95.439074] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 95.440411] CPU: 7 PID: 0 Comm: swapper/7 Not tainted 6.9.3-dirty #1 [ 95.441558] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 12/12/2018 [ 95.443481] RIP: 0010:skb_panic+0x4d/0x4f [ 95.444404] Code: 4f 70 50 8b 87 c0 00 00 00 50 8b 87 bc 00 00 00 50 ff b7 d0 00 00 00 4c 8b 8f c8 00 00 00 48 c7 c7 68 e8 be 9f e8 63 58 f9 ff <0f> 0b 48 8b 14 24 48 c7 c1 d0 73 65 9f e8 a1 ff ff ff 48 8b 14 24 [ 95.447684] RSP: 0018:ffffa13340274dd0 EFLAGS: 00010246 [ 95.448762] RAX: 0000000000000089 RBX: ffff8fbbc72b02d0 RCX: 000000000000083f [ 95.450148] RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f [ 95.451520] RBP: 000000000000002d R08: 0000000000000000 R09: ffffa13340274c60 [ 95.452886] R10: ffffffffa04ed468 R11: 0000000000000002 R12: 0000000000000000 [ 95.454293] R13: ffff8fbbdab3c2d0 R14: ffff8fbbdbd829e0 R15: ffff8fbbdbd809e0 [ 95.455682] FS: 0000000000000000(0000) GS:ffff8fbeefd80000(0000) knlGS:0000000000000000 [ 95.457178] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 95.458340] CR2: 00007fd0d1f650c8 CR3: 0000000115f28000 CR4: 00000000000406f0 [ 95.459791] Call Trace: [ 95.460515] <IRQ> [ 95.461180] ? __die_body.cold+0x19/0x27 [ 95.462150] ? die+0x2e/0x50 [ 95.462976] ? do_trap+0xca/0x110 [ 95.463973] ? do_error_trap+0x6a/0x90 [ 95.464966] ? skb_panic+0x4d/0x4f [ 95.465901] ? exc_invalid_op+0x50/0x70 [ 95.466849] ? skb_panic+0x4d/0x4f [ 95.467718] ? asm_exc_invalid_op+0x1a/0x20 [ 95.468758] ? skb_panic+0x4d/0x4f [ 95.469655] skb_put.cold+0x10/0x10 [ 95.470573] vmxnet3_rq_rx_complete+0x862/0x11e0 [vmxnet3] [ 95.471853] vmxnet3_poll_rx_only+0x36/0xb0 [vmxnet3] [ 95.473185] __napi_poll+0x2b/0x160 [ 95.474145] net_rx_action+0x2c6/0x3b0 [ 95.475115] handle_softirqs+0xe7/0x2a0 [ 95.476122] __irq_exit_rcu+0x97/0xb0 [ 95.477109] common_interrupt+0x85/0xa0 [ 95.478102] </IRQ> [ 95.478846] <TASK> [ 95.479603] asm_common_interrupt+0x26/0x40 [ 95.480657] RIP: 0010:pv_native_safe_halt+0xf/0x20 [ 95.481801] Code: 22 d7 e9 54 87 01 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 93 ba 3b 00 fb f4 <e9> 2c 87 01 00 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 [ 95.485563] RSP: 0018:ffffa133400ffe58 EFLAGS: 00000246 [ 95.486882] RAX: 0000000000004000 RBX: ffff8fbbc1d14064 RCX: 0000000000000000 [ 95.488477] RDX: ffff8fbeefd80000 RSI: ffff8fbbc1d14000 RDI: 0000000000000001 [ 95.490067] RBP: ffff8fbbc1d14064 R08: ffffffffa0652260 R09: 00000000000010d3 [ 95.491683] R10: 0000000000000018 R11: ffff8fbeefdb4764 R12: ffffffffa0652260 [ 95.493389] R13: ffffffffa06522e0 R14: 0000000000000001 R15: 0000000000000000 [ 95.495035] acpi_safe_halt+0x14/0x20 [ 95.496127] acpi_idle_do_entry+0x2f/0x50 [ 95.497221] acpi_idle_enter+0x7f/0xd0 [ 95.498272] cpuidle_enter_state+0x81/0x420 [ 95.499375] cpuidle_enter+0x2d/0x40 [ 95.500400] do_idle+0x1e5/0x240 [ 95.501385] cpu_startup_entry+0x29/0x30 [ 95.502422] start_secondary+0x11c/0x140 [ 95.503454] common_startup_64+0x13e/0x141 [ 95.504466] </TASK> [ 95.505197] Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ip ---truncated---

In the Linux kernel, the following vulnerability has been resolved: io_uring/rsrc: don't lock while !TASK_RUNNING There is a report of io_rsrc_ref_quiesce() locking a mutex while not TASK_RUNNING, which is due to forgetting restoring the state back after io_run_task_work_sig() and attempts to break out of the waiting loop. do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff815d2494>] prepare_to_wait+0xa4/0x380 kernel/sched/wait.c:237 WARNING: CPU: 2 PID: 397056 at kernel/sched/core.c:10099 __might_sleep+0x114/0x160 kernel/sched/core.c:10099 RIP: 0010:__might_sleep+0x114/0x160 kernel/sched/core.c:10099 Call Trace: <TASK> __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0xb4/0x940 kernel/locking/mutex.c:752 io_rsrc_ref_quiesce+0x590/0x940 io_uring/rsrc.c:253 io_sqe_buffers_unregister+0xa2/0x340 io_uring/rsrc.c:799 __io_uring_register io_uring/register.c:424 [inline] __do_sys_io_uring_register+0x5b9/0x2400 io_uring/register.c:613 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd8/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77

In the Linux kernel, the following vulnerability has been resolved: net: bridge: mst: pass vlan group directly to br_mst_vlan_set_state Pass the already obtained vlan group pointer to br_mst_vlan_set_state() instead of dereferencing it again. Each caller has already correctly dereferenced it for their context. This change is required for the following suspicious RCU dereference fix. No functional changes intended.

In the Linux kernel, the following vulnerability has been resolved: net: bridge: mst: fix suspicious rcu usage in br_mst_set_state I converted br_mst_set_state to RCU to avoid a vlan use-after-free but forgot to change the vlan group dereference helper. Switch to vlan group RCU deref helper to fix the suspicious rcu usage warning.

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Adjust logging of firmware messages in case of released token in __hwrm_send() In case of token is released due to token->state == BNXT_HWRM_DEFERRED, released token (set to NULL) is used in log messages. This issue is expected to be prevented by HWRM_ERR_CODE_PF_UNAVAILABLE error code. But this error code is returned by recent firmware. So some firmware may not return it. This may lead to NULL pointer dereference. Adjust this issue by adding token pointer check. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: parisc: Try to fix random segmentation faults in package builds PA-RISC systems with PA8800 and PA8900 processors have had problems with random segmentation faults for many years. Systems with earlier processors are much more stable. Systems with PA8800 and PA8900 processors have a large L2 cache which needs per page flushing for decent performance when a large range is flushed. The combined cache in these systems is also more sensitive to non-equivalent aliases than the caches in earlier systems. The majority of random segmentation faults that I have looked at appear to be memory corruption in memory allocated using mmap and malloc. My first attempt at fixing the random faults didn't work. On reviewing the cache code, I realized that there were two issues which the existing code didn't handle correctly. Both relate to cache move-in. Another issue is that the present bit in PTEs is racy. 1) PA-RISC caches have a mind of their own and they can speculatively load data and instructions for a page as long as there is a entry in the TLB for the page which allows move-in. TLBs are local to each CPU. Thus, the TLB entry for a page must be purged before flushing the page. This is particularly important on SMP systems. In some of the flush routines, the flush routine would be called and then the TLB entry would be purged. This was because the flush routine needed the TLB entry to do the flush. 2) My initial approach to trying the fix the random faults was to try and use flush_cache_page_if_present for all flush operations. This actually made things worse and led to a couple of hardware lockups. It finally dawned on me that some lines weren't being flushed because the pte check code was racy. This resulted in random inequivalent mappings to physical pages. The __flush_cache_page tmpalias flush sets up its own TLB entry and it doesn't need the existing TLB entry. As long as we can find the pte pointer for the vm page, we can get the pfn and physical address of the page. We can also purge the TLB entry for the page before doing the flush. Further, __flush_cache_page uses a special TLB entry that inhibits cache move-in. When switching page mappings, we need to ensure that lines are removed from the cache. It is not sufficient to just flush the lines to memory as they may come back. This made it clear that we needed to implement all the required flush operations using tmpalias routines. This includes flushes for user and kernel pages. After modifying the code to use tmpalias flushes, it became clear that the random segmentation faults were not fully resolved. The frequency of faults was worse on systems with a 64 MB L2 (PA8900) and systems with more CPUs (rp4440). The warning that I added to flush_cache_page_if_present to detect pages that couldn't be flushed triggered frequently on some systems. Helge and I looked at the pages that couldn't be flushed and found that the PTE was either cleared or for a swap page. Ignoring pages that were swapped out seemed okay but pages with cleared PTEs seemed problematic. I looked at routines related to pte_clear and noticed ptep_clear_flush. The default implementation just flushes the TLB entry. However, it was obvious that on parisc we need to flush the cache page as well. If we don't flush the cache page, stale lines will be left in the cache and cause random corruption. Once a PTE is cleared, there is no way to find the physical address associated with the PTE and flush the associated page at a later time. I implemented an updated change with a parisc specific version of ptep_clear_flush. It fixed the random data corruption on Helge's rp4440 and rp3440, as well as on my c8000. At this point, I realized that I could restore the code where we only flush in flush_cache_page_if_present if the page has been accessed. However, for this, we also need to flush the cache when the accessed bit is cleared in ---truncated---

In the Linux kernel, the following vulnerability has been resolved: memblock: make memblock_set_node() also warn about use of MAX_NUMNODES On an (old) x86 system with SRAT just covering space above 4Gb: ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0xfffffffff] hotplug the commit referenced below leads to this NUMA configuration no longer being refused by a CONFIG_NUMA=y kernel (previously NUMA: nodes only cover 6144MB of your 8185MB e820 RAM. Not used. No NUMA configuration found Faking a node at [mem 0x0000000000000000-0x000000027fffffff] was seen in the log directly after the message quoted above), because of memblock_validate_numa_coverage() checking for NUMA_NO_NODE (only). This in turn led to memblock_alloc_range_nid()'s warning about MAX_NUMNODES triggering, followed by a NULL deref in memmap_init() when trying to access node 64's (NODE_SHIFT=6) node data. To compensate said change, make memblock_set_node() warn on and adjust a passed in value of MAX_NUMNODES, just like various other functions already do.

In the Linux kernel, the following vulnerability has been resolved: drm/exynos: hdmi: report safe 640x480 mode as a fallback when no EDID found When reading EDID fails and driver reports no modes available, the DRM core adds an artificial 1024x786 mode to the connector. Unfortunately some variants of the Exynos HDMI (like the one in Exynos4 SoCs) are not able to drive such mode, so report a safe 640x480 mode instead of nothing in case of the EDID reading failure. This fixes the following issue observed on Trats2 board since commit 13d5b040363c ("drm/exynos: do not return negative values from .get_modes()"): [drm] Exynos DRM: using 11c00000.fimd device for DMA mapping operations exynos-drm exynos-drm: bound 11c00000.fimd (ops fimd_component_ops) exynos-drm exynos-drm: bound 12c10000.mixer (ops mixer_component_ops) exynos-dsi 11c80000.dsi: [drm:samsung_dsim_host_attach] Attached s6e8aa0 device (lanes:4 bpp:24 mode-flags:0x10b) exynos-drm exynos-drm: bound 11c80000.dsi (ops exynos_dsi_component_ops) exynos-drm exynos-drm: bound 12d00000.hdmi (ops hdmi_component_ops) [drm] Initialized exynos 1.1.0 20180330 for exynos-drm on minor 1 exynos-hdmi 12d00000.hdmi: [drm:hdmiphy_enable.part.0] *ERROR* PLL could not reach steady state panel-samsung-s6e8aa0 11c80000.dsi.0: ID: 0xa2, 0x20, 0x8c exynos-mixer 12c10000.mixer: timeout waiting for VSYNC ------------[ cut here ]------------ WARNING: CPU: 1 PID: 11 at drivers/gpu/drm/drm_atomic_helper.c:1682 drm_atomic_helper_wait_for_vblanks.part.0+0x2b0/0x2b8 [CRTC:70:crtc-1] vblank wait timed out Modules linked in: CPU: 1 PID: 11 Comm: kworker/u16:0 Not tainted 6.9.0-rc5-next-20240424 #14913 Hardware name: Samsung Exynos (Flattened Device Tree) Workqueue: events_unbound deferred_probe_work_func Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x68/0x88 dump_stack_lvl from __warn+0x7c/0x1c4 __warn from warn_slowpath_fmt+0x11c/0x1a8 warn_slowpath_fmt from drm_atomic_helper_wait_for_vblanks.part.0+0x2b0/0x2b8 drm_atomic_helper_wait_for_vblanks.part.0 from drm_atomic_helper_commit_tail_rpm+0x7c/0x8c drm_atomic_helper_commit_tail_rpm from commit_tail+0x9c/0x184 commit_tail from drm_atomic_helper_commit+0x168/0x190 drm_atomic_helper_commit from drm_atomic_commit+0xb4/0xe0 drm_atomic_commit from drm_client_modeset_commit_atomic+0x23c/0x27c drm_client_modeset_commit_atomic from drm_client_modeset_commit_locked+0x60/0x1cc drm_client_modeset_commit_locked from drm_client_modeset_commit+0x24/0x40 drm_client_modeset_commit from __drm_fb_helper_restore_fbdev_mode_unlocked+0x9c/0xc4 __drm_fb_helper_restore_fbdev_mode_unlocked from drm_fb_helper_set_par+0x2c/0x3c drm_fb_helper_set_par from fbcon_init+0x3d8/0x550 fbcon_init from visual_init+0xc0/0x108 visual_init from do_bind_con_driver+0x1b8/0x3a4 do_bind_con_driver from do_take_over_console+0x140/0x1ec do_take_over_console from do_fbcon_takeover+0x70/0xd0 do_fbcon_takeover from fbcon_fb_registered+0x19c/0x1ac fbcon_fb_registered from register_framebuffer+0x190/0x21c register_framebuffer from __drm_fb_helper_initial_config_and_unlock+0x350/0x574 __drm_fb_helper_initial_config_and_unlock from exynos_drm_fbdev_client_hotplug+0x6c/0xb0 exynos_drm_fbdev_client_hotplug from drm_client_register+0x58/0x94 drm_client_register from exynos_drm_bind+0x160/0x190 exynos_drm_bind from try_to_bring_up_aggregate_device+0x200/0x2d8 try_to_bring_up_aggregate_device from __component_add+0xb0/0x170 __component_add from mixer_probe+0x74/0xcc mixer_probe from platform_probe+0x5c/0xb8 platform_probe from really_probe+0xe0/0x3d8 really_probe from __driver_probe_device+0x9c/0x1e4 __driver_probe_device from driver_probe_device+0x30/0xc0 driver_probe_device from __device_attach_driver+0xa8/0x120 __device_attach_driver from bus_for_each_drv+0x80/0xcc bus_for_each_drv from __device_attach+0xac/0x1fc __device_attach from bus_probe_device+0x8c/0x90 bus_probe_device from deferred_probe_work_func+0 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context __kernel_map_pages() is a debug function which clears the valid bit in page table entry for deallocated pages to detect illegal memory accesses to freed pages. This function set/clear the valid bit using __set_memory(). __set_memory() acquires init_mm's semaphore, and this operation may sleep. This is problematic, because __kernel_map_pages() can be called in atomic context, and thus is illegal to sleep. An example warning that this causes: BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1578 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd preempt_count: 2, expected: 0 CPU: 0 PID: 2 Comm: kthreadd Not tainted 6.9.0-g1d4c6d784ef6 #37 Hardware name: riscv-virtio,qemu (DT) Call Trace: [<ffffffff800060dc>] dump_backtrace+0x1c/0x24 [<ffffffff8091ef6e>] show_stack+0x2c/0x38 [<ffffffff8092baf8>] dump_stack_lvl+0x5a/0x72 [<ffffffff8092bb24>] dump_stack+0x14/0x1c [<ffffffff8003b7ac>] __might_resched+0x104/0x10e [<ffffffff8003b7f4>] __might_sleep+0x3e/0x62 [<ffffffff8093276a>] down_write+0x20/0x72 [<ffffffff8000cf00>] __set_memory+0x82/0x2fa [<ffffffff8000d324>] __kernel_map_pages+0x5a/0xd4 [<ffffffff80196cca>] __alloc_pages_bulk+0x3b2/0x43a [<ffffffff8018ee82>] __vmalloc_node_range+0x196/0x6ba [<ffffffff80011904>] copy_process+0x72c/0x17ec [<ffffffff80012ab4>] kernel_clone+0x60/0x2fe [<ffffffff80012f62>] kernel_thread+0x82/0xa0 [<ffffffff8003552c>] kthreadd+0x14a/0x1be [<ffffffff809357de>] ret_from_fork+0xe/0x1c Rewrite this function with apply_to_existing_page_range(). It is fine to not have any locking, because __kernel_map_pages() works with pages being allocated/deallocated and those pages are not changed by anyone else in the meantime.

In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: don't unpoison huge_zero_folio When I did memory failure tests recently, below panic occurs: kernel BUG at include/linux/mm.h:1135! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 9 PID: 137 Comm: kswapd1 Not tainted 6.9.0-rc4-00491-gd5ce28f156fe-dirty #14 RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 Call Trace: <TASK> do_shrink_slab+0x14f/0x6a0 shrink_slab+0xca/0x8c0 shrink_node+0x2d0/0x7d0 balance_pgdat+0x33a/0x720 kswapd+0x1f3/0x410 kthread+0xd5/0x100 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: mce_inject hwpoison_inject ---[ end trace 0000000000000000 ]--- RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 The root cause is that HWPoison flag will be set for huge_zero_folio without increasing the folio refcnt. But then unpoison_memory() will decrease the folio refcnt unexpectedly as it appears like a successfully hwpoisoned folio leading to VM_BUG_ON_PAGE(page_ref_count(page) == 0) when releasing huge_zero_folio. Skip unpoisoning huge_zero_folio in unpoison_memory() to fix this issue. We're not prepared to unpoison huge_zero_folio yet.

In the Linux kernel, the following vulnerability has been resolved: cachefiles: defer exposing anon_fd until after copy_to_user() succeeds After installing the anonymous fd, we can now see it in userland and close it. However, at this point we may not have gotten the reference count of the cache, but we will put it during colse fd, so this may cause a cache UAF. So grab the cache reference count before fd_install(). In addition, by kernel convention, fd is taken over by the user land after fd_install(), and the kernel should not call close_fd() after that, i.e., it should call fd_install() after everything is ready, thus fd_install() is called after copy_to_user() succeeds.

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: Fix deadlock in ieee80211_sta_ps_deliver_wakeup() The ieee80211_sta_ps_deliver_wakeup() function takes sta->ps_lock to synchronizes with ieee80211_tx_h_unicast_ps_buf() which is called from softirq context. However using only spin_lock() to get sta->ps_lock in ieee80211_sta_ps_deliver_wakeup() does not prevent softirq to execute on this same CPU, to run ieee80211_tx_h_unicast_ps_buf() and try to take this same lock ending in deadlock. Below is an example of rcu stall that arises in such situation. rcu: INFO: rcu_sched self-detected stall on CPU rcu: 2-....: (42413413 ticks this GP) idle=b154/1/0x4000000000000000 softirq=1763/1765 fqs=21206996 rcu: (t=42586894 jiffies g=2057 q=362405 ncpus=4) CPU: 2 PID: 719 Comm: wpa_supplicant Tainted: G W 6.4.0-02158-g1b062f552873 #742 Hardware name: RPT (r1) (DT) pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : queued_spin_lock_slowpath+0x58/0x2d0 lr : invoke_tx_handlers_early+0x5b4/0x5c0 sp : ffff00001ef64660 x29: ffff00001ef64660 x28: ffff000009bc1070 x27: ffff000009bc0ad8 x26: ffff000009bc0900 x25: ffff00001ef647a8 x24: 0000000000000000 x23: ffff000009bc0900 x22: ffff000009bc0900 x21: ffff00000ac0e000 x20: ffff00000a279e00 x19: ffff00001ef646e8 x18: 0000000000000000 x17: ffff800016468000 x16: ffff00001ef608c0 x15: 0010533c93f64f80 x14: 0010395c9faa3946 x13: 0000000000000000 x12: 00000000fa83b2da x11: 000000012edeceea x10: ffff0000010fbe00 x9 : 0000000000895440 x8 : 000000000010533c x7 : ffff00000ad8b740 x6 : ffff00000c350880 x5 : 0000000000000007 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff00000ac0e0e8 Call trace: queued_spin_lock_slowpath+0x58/0x2d0 ieee80211_tx+0x80/0x12c ieee80211_tx_pending+0x110/0x278 tasklet_action_common.constprop.0+0x10c/0x144 tasklet_action+0x20/0x28 _stext+0x11c/0x284 ____do_softirq+0xc/0x14 call_on_irq_stack+0x24/0x34 do_softirq_own_stack+0x18/0x20 do_softirq+0x74/0x7c __local_bh_enable_ip+0xa0/0xa4 _ieee80211_wake_txqs+0x3b0/0x4b8 __ieee80211_wake_queue+0x12c/0x168 ieee80211_add_pending_skbs+0xec/0x138 ieee80211_sta_ps_deliver_wakeup+0x2a4/0x480 ieee80211_mps_sta_status_update.part.0+0xd8/0x11c ieee80211_mps_sta_status_update+0x18/0x24 sta_apply_parameters+0x3bc/0x4c0 ieee80211_change_station+0x1b8/0x2dc nl80211_set_station+0x444/0x49c genl_family_rcv_msg_doit.isra.0+0xa4/0xfc genl_rcv_msg+0x1b0/0x244 netlink_rcv_skb+0x38/0x10c genl_rcv+0x34/0x48 netlink_unicast+0x254/0x2bc netlink_sendmsg+0x190/0x3b4 ____sys_sendmsg+0x1e8/0x218 ___sys_sendmsg+0x68/0x8c __sys_sendmsg+0x44/0x84 __arm64_sys_sendmsg+0x20/0x28 do_el0_svc+0x6c/0xe8 el0_svc+0x14/0x48 el0t_64_sync_handler+0xb0/0xb4 el0t_64_sync+0x14c/0x150 Using spin_lock_bh()/spin_unlock_bh() instead prevents softirq to raise on the same CPU that is holding the lock.