In the Linux kernel, the following vulnerability has been resolved: erofs: fix pcluster use-after-free on UP platforms During stress testing with CONFIG_SMP disabled, KASAN reports as below: ================================================================== BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30 Read of size 8 at addr ffff8881094223f8 by task stress/7789 CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Call Trace: <TASK> .. __mutex_lock+0xe5/0xc30 .. z_erofs_do_read_page+0x8ce/0x1560 .. z_erofs_readahead+0x31c/0x580 .. Freed by task 7787 kasan_save_stack+0x1e/0x40 kasan_set_track+0x20/0x30 kasan_set_free_info+0x20/0x40 __kasan_slab_free+0x10c/0x190 kmem_cache_free+0xed/0x380 rcu_core+0x3d5/0xc90 __do_softirq+0x12d/0x389 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xb0 call_rcu+0x3d/0x3f0 erofs_shrink_workstation+0x11f/0x210 erofs_shrink_scan+0xdc/0x170 shrink_slab.constprop.0+0x296/0x530 drop_slab+0x1c/0x70 drop_caches_sysctl_handler+0x70/0x80 proc_sys_call_handler+0x20a/0x2f0 vfs_write+0x555/0x6c0 ksys_write+0xbe/0x160 do_syscall_64+0x3b/0x90 The root cause is that erofs_workgroup_unfreeze() doesn't reset to orig_val thus it causes a race that the pcluster reuses unexpectedly before freeing. Since UP platforms are quite rare now, such path becomes unnecessary. Let's drop such specific-designed path directly instead.
In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: fix UAF when detecting digest errors We should also bail from the io_work loop when we set rd_enabled to true, so we don't attempt to read data from the socket when the TCP stream is already out-of-sync or corrupted.
In the Linux kernel, the following vulnerability has been resolved: net: ll_temac: Make sure to free skb when it is completely used With the skb pointer piggy-backed on the TX BD, we have a simple and efficient way to free the skb buffer when the frame has been transmitted. But in order to avoid freeing the skb while there are still fragments from the skb in use, we need to piggy-back on the TX BD of the skb, not the first. Without this, we are doing use-after-free on the DMA side, when the first BD of a multi TX BD packet is seen as completed in xmit_done, and the remaining BDs are still being processed.
In the Linux kernel, the following vulnerability has been resolved: PCI: Fix active state requirement in PME polling The commit noted in fixes added a bogus requirement that runtime PM managed devices need to be in the RPM_ACTIVE state for PME polling. In fact, only devices in low power states should be polled. However there's still a requirement that the device config space must be accessible, which has implications for both the current state of the polled device and the parent bridge, when present. It's not sufficient to assume the bridge remains in D0 and cases have been observed where the bridge passes the D0 test, but the PM state indicates RPM_SUSPENDING and config space of the polled device becomes inaccessible during pci_pme_wakeup(). Therefore, since the bridge is already effectively required to be in the RPM_ACTIVE state, formalize this in the code and elevate the PM usage count to maintain the state while polling the subordinate device. This resolves a regression reported in the bugzilla below where a Thunderbolt/USB4 hierarchy fails to scan for an attached NVMe endpoint downstream of a bridge in a D3hot power state.
In the Linux kernel, the following vulnerability has been resolved: ASoC: qcom: Fix uninitialized pointer dmactl In the case where __lpass_get_dmactl_handle is called and the driver id dai_id is invalid the pointer dmactl is not being assigned a value, and dmactl contains a garbage value since it has not been initialized and so the null check may not work. Fix this to initialize dmactl to NULL. One could argue that modern compilers will set this to zero, but it is useful to keep this initialized as per the same way in functions __lpass_platform_codec_intf_init and lpass_cdc_dma_daiops_hw_params. Cleans up clang scan build warning: sound/soc/qcom/lpass-cdc-dma.c:275:7: warning: Branch condition evaluates to a garbage value [core.uninitialized.Branch]
In the Linux kernel, the following vulnerability has been resolved: sfc/siena: fix null pointer dereference in efx_hard_start_xmit Like in previous patch for sfc, prevent potential (but unlikely) NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved: arm64: extable: fix load_unaligned_zeropad() reg indices In ex_handler_load_unaligned_zeropad() we erroneously extract the data and addr register indices from ex->type rather than ex->data. As ex->type will contain EX_TYPE_LOAD_UNALIGNED_ZEROPAD (i.e. 4): * We'll always treat X0 as the address register, since EX_DATA_REG_ADDR is extracted from bits [9:5]. Thus, we may attempt to dereference an arbitrary address as X0 may hold an arbitrary value. * We'll always treat X4 as the data register, since EX_DATA_REG_DATA is extracted from bits [4:0]. Thus we will corrupt X4 and cause arbitrary behaviour within load_unaligned_zeropad() and its caller. Fix this by extracting both values from ex->data as originally intended. On an MTE-enabled QEMU image we are hitting the following crash: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Call trace: fixup_exception+0xc4/0x108 __do_kernel_fault+0x3c/0x268 do_tag_check_fault+0x3c/0x104 do_mem_abort+0x44/0xf4 el1_abort+0x40/0x64 el1h_64_sync_handler+0x60/0xa0 el1h_64_sync+0x7c/0x80 link_path_walk+0x150/0x344 path_openat+0xa0/0x7dc do_filp_open+0xb8/0x168 do_sys_openat2+0x88/0x17c __arm64_sys_openat+0x74/0xa0 invoke_syscall+0x48/0x148 el0_svc_common+0xb8/0xf8 do_el0_svc+0x28/0x88 el0_svc+0x24/0x84 el0t_64_sync_handler+0x88/0xec el0t_64_sync+0x1b4/0x1b8 Code: f8695a69 71007d1f 540000e0 927df12a (f940014a)
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: don't fail inserts if duplicate has expired nftables selftests fail: run-tests.sh testcases/sets/0044interval_overlap_0 Expected: 0-2 . 0-3, got: W: [FAILED] ./testcases/sets/0044interval_overlap_0: got 1 Insertion must ignore duplicate but expired entries. Moreover, there is a strange asymmetry in nft_pipapo_activate: It refetches the current element, whereas the other ->activate callbacks (bitmap, hash, rhash, rbtree) use elem->priv. Same for .remove: other set implementations take elem->priv, nft_pipapo_remove fetches elem->priv, then does a relookup, remove this. I suspect this was the reason for the change that prompted the removal of the expired check in pipapo_get() in the first place, but skipping exired elements there makes no sense to me, this helper is used for normal get requests, insertions (duplicate check) and deactivate callback. In first two cases expired elements must be skipped. For ->deactivate(), this gets called for DELSETELEM, so it seems to me that expired elements should be skipped as well, i.e. delete request should fail with -ENOENT error.
In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: clk-mt7629: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved: media: vidtv: psi: Add check for kstrdup Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved: drm: bridge: it66121: Fix invalid connector dereference Fix the NULL pointer dereference when no monitor is connected, and the sound card is opened from userspace. Instead return an empty buffer (of zeroes) as the EDID information to the sound framework if there is no connector attached.
In the Linux kernel, the following vulnerability has been resolved: mfd: qcom-spmi-pmic: Fix revid implementation The Qualcomm SPMI PMIC revid implementation is broken in multiple ways. First, it assumes that just because the sibling base device has been registered that means that it is also bound to a driver, which may not be the case (e.g. due to probe deferral or asynchronous probe). This could trigger a NULL-pointer dereference when attempting to access the driver data of the unbound device. Second, it accesses driver data of a sibling device directly and without any locking, which means that the driver data may be freed while it is being accessed (e.g. on driver unbind). Third, it leaks a struct device reference to the sibling device which is looked up using the spmi_device_from_of() every time a function (child) device is calling the revid function (e.g. on probe). Fix this mess by reimplementing the revid lookup so that it is done only at probe of the PMIC device; the base device fetches the revid info from the hardware, while any secondary SPMI device fetches the information from the base device and caches it so that it can be accessed safely from its children. If the base device has not been probed yet then probe of a secondary device is deferred.
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_payload: sanitize offset and length before calling skb_checksum() If access to offset + length is larger than the skbuff length, then skb_checksum() triggers BUG_ON(). skb_checksum() internally subtracts the length parameter while iterating over skbuff, BUG_ON(len) at the end of it checks that the expected length to be included in the checksum calculation is fully consumed.
In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix possible out-of-bound write in ath12k_wmi_ext_hal_reg_caps() reg_cap.phy_id is extracted from WMI event and could be an unexpected value in case some errors happen. As a result out-of-bound write may occur to soc->hal_reg_cap. Fix it by validating reg_cap.phy_id before using it. This is found during code review. Compile tested only.
In the Linux kernel, the following vulnerability has been resolved: workqueue: Fix selection of wake_cpu in kick_pool() With cpu_possible_mask=0-63 and cpu_online_mask=0-7 the following kernel oops was observed: smp: Bringing up secondary CPUs ... smp: Brought up 1 node, 8 CPUs Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000000000000 TEID: 0000000000000803 [..] Call Trace: arch_vcpu_is_preempted+0x12/0x80 select_idle_sibling+0x42/0x560 select_task_rq_fair+0x29a/0x3b0 try_to_wake_up+0x38e/0x6e0 kick_pool+0xa4/0x198 __queue_work.part.0+0x2bc/0x3a8 call_timer_fn+0x36/0x160 __run_timers+0x1e2/0x328 __run_timer_base+0x5a/0x88 run_timer_softirq+0x40/0x78 __do_softirq+0x118/0x388 irq_exit_rcu+0xc0/0xd8 do_ext_irq+0xae/0x168 ext_int_handler+0xbe/0xf0 psw_idle_exit+0x0/0xc default_idle_call+0x3c/0x110 do_idle+0xd4/0x158 cpu_startup_entry+0x40/0x48 rest_init+0xc6/0xc8 start_kernel+0x3c4/0x5e0 startup_continue+0x3c/0x50 The crash is caused by calling arch_vcpu_is_preempted() for an offline CPU. To avoid this, select the cpu with cpumask_any_and_distribute() to mask __pod_cpumask with cpu_online_mask. In case no cpu is left in the pool, skip the assignment. tj: This doesn't fully fix the bug as CPUs can still go down between picking the target CPU and the wake call. Fixing that likely requires adding cpu_online() test to either the sched or s390 arch code. However, regardless of how that is fixed, workqueue shouldn't be picking a CPU which isn't online as that would result in unpredictable and worse behavior.
In the Linux kernel, the following vulnerability has been resolved: scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc() Calling scsi_remove_host() before scsi_add_host() results in a crash: BUG: kernel NULL pointer dereference, address: 0000000000000108 RIP: 0010:device_del+0x63/0x440 Call Trace: device_unregister+0x17/0x60 scsi_remove_host+0xee/0x2a0 pm8001_pci_probe+0x6ef/0x1b90 [pm80xx] local_pci_probe+0x3f/0x90 We cannot call scsi_remove_host() in pm8001_alloc() because scsi_add_host() has not been called yet at that point in time. Function call tree: pm8001_pci_probe() | `- pm8001_pci_alloc() | | | `- pm8001_alloc() | | | `- scsi_remove_host() | `- scsi_add_host()
In the Linux kernel, the following vulnerability has been resolved: x86/ioremap: Map EFI-reserved memory as encrypted for SEV Some drivers require memory that is marked as EFI boot services data. In order for this memory to not be re-used by the kernel after ExitBootServices(), efi_mem_reserve() is used to preserve it by inserting a new EFI memory descriptor and marking it with the EFI_MEMORY_RUNTIME attribute. Under SEV, memory marked with the EFI_MEMORY_RUNTIME attribute needs to be mapped encrypted by Linux, otherwise the kernel might crash at boot like below: EFI Variables Facility v0.08 2004-May-17 general protection fault, probably for non-canonical address 0x3597688770a868b2: 0000 [#1] SMP NOPTI CPU: 13 PID: 1 Comm: swapper/0 Not tainted 5.12.4-2-default #1 openSUSE Tumbleweed Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:efi_mokvar_entry_next [...] Call Trace: efi_mokvar_sysfs_init ? efi_mokvar_table_init do_one_initcall ? __kmalloc kernel_init_freeable ? rest_init kernel_init ret_from_fork Expand the __ioremap_check_other() function to additionally check for this other type of boot data reserved at runtime and indicate that it should be mapped encrypted for an SEV guest. [ bp: Massage commit message. ]
In the Linux kernel, the following vulnerability has been resolved: drm/msm/a6xx: Allocate enough space for GMU registers In commit 142639a52a01 ("drm/msm/a6xx: fix crashstate capture for A650") we changed a6xx_get_gmu_registers() to read 3 sets of registers. Unfortunately, we didn't change the memory allocation for the array. That leads to a KASAN warning (this was on the chromeos-5.4 kernel, which has the problematic commit backported to it): BUG: KASAN: slab-out-of-bounds in _a6xx_get_gmu_registers+0x144/0x430 Write of size 8 at addr ffffff80c89432b0 by task A618-worker/209 CPU: 5 PID: 209 Comm: A618-worker Tainted: G W 5.4.156-lockdep #22 Hardware name: Google Lazor Limozeen without Touchscreen (rev5 - rev8) (DT) Call trace: dump_backtrace+0x0/0x248 show_stack+0x20/0x2c dump_stack+0x128/0x1ec print_address_description+0x88/0x4a0 __kasan_report+0xfc/0x120 kasan_report+0x10/0x18 __asan_report_store8_noabort+0x1c/0x24 _a6xx_get_gmu_registers+0x144/0x430 a6xx_gpu_state_get+0x330/0x25d4 msm_gpu_crashstate_capture+0xa0/0x84c recover_worker+0x328/0x838 kthread_worker_fn+0x32c/0x574 kthread+0x2dc/0x39c ret_from_fork+0x10/0x18 Allocated by task 209: __kasan_kmalloc+0xfc/0x1c4 kasan_kmalloc+0xc/0x14 kmem_cache_alloc_trace+0x1f0/0x2a0 a6xx_gpu_state_get+0x164/0x25d4 msm_gpu_crashstate_capture+0xa0/0x84c recover_worker+0x328/0x838 kthread_worker_fn+0x32c/0x574 kthread+0x2dc/0x39c ret_from_fork+0x10/0x18
In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: Fix a resource leak in an error handling path If an error occurs after a successful 'pci_ioremap_bar()' call, it must be undone by a corresponding 'pci_iounmap()' call, as already done in the remove function.
In the Linux kernel, the following vulnerability has been resolved: scsi: megaraid_sas: Fix resource leak in case of probe failure The driver doesn't clean up all the allocated resources properly when scsi_add_host(), megasas_start_aen() function fails during the PCI device probe. Clean up all those resources.
In the Linux kernel, the following vulnerability has been resolved: mptcp: Fix out of bounds when parsing TCP options The TCP option parser in mptcp (mptcp_get_options) could read one byte out of bounds. When the length is 1, the execution flow gets into the loop, reads one byte of the opcode, and if the opcode is neither TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds the length of 1. This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack out of bounds when parsing TCP options.").
In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries/iommu: LPAR panics during boot up with a frozen PE At the time of LPAR boot up, partition firmware provides Open Firmware property ibm,dma-window for the PE. This property is provided on the PCI bus the PE is attached to. There are execptions where the partition firmware might not provide this property for the PE at the time of LPAR boot up. One of the scenario is where the firmware has frozen the PE due to some error condition. This PE is frozen for 24 hours or unless the whole system is reinitialized. Within this time frame, if the LPAR is booted, the frozen PE will be presented to the LPAR but ibm,dma-window property could be missing. Today, under these circumstances, the LPAR oopses with NULL pointer dereference, when configuring the PCI bus the PE is attached to. BUG: Kernel NULL pointer dereference on read at 0x000000c8 Faulting instruction address: 0xc0000000001024c0 Oops: Kernel access of bad area, sig: 7 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: Supported: Yes CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0-150600.9-default #1 Hardware name: IBM,9043-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_023) hv:phyp pSeries NIP: c0000000001024c0 LR: c0000000001024b0 CTR: c000000000102450 REGS: c0000000037db5c0 TRAP: 0300 Not tainted (6.4.0-150600.9-default) MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 28000822 XER: 00000000 CFAR: c00000000010254c DAR: 00000000000000c8 DSISR: 00080000 IRQMASK: 0 ... NIP [c0000000001024c0] pci_dma_bus_setup_pSeriesLP+0x70/0x2a0 LR [c0000000001024b0] pci_dma_bus_setup_pSeriesLP+0x60/0x2a0 Call Trace: pci_dma_bus_setup_pSeriesLP+0x60/0x2a0 (unreliable) pcibios_setup_bus_self+0x1c0/0x370 __of_scan_bus+0x2f8/0x330 pcibios_scan_phb+0x280/0x3d0 pcibios_init+0x88/0x12c do_one_initcall+0x60/0x320 kernel_init_freeable+0x344/0x3e4 kernel_init+0x34/0x1d0 ret_from_kernel_user_thread+0x14/0x1c
In the Linux kernel, the following vulnerability has been resolved: uio_hv_generic: Don't free decrypted memory In CoCo VMs it is possible for the untrusted host to cause set_memory_encrypted() or set_memory_decrypted() to fail such that an error is returned and the resulting memory is shared. Callers need to take care to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. The VMBus device UIO driver could free decrypted/shared pages if set_memory_decrypted() fails. Check the decrypted field in the gpadl to decide whether to free the memory.
Guests can trigger deadlock in Linux netback driver T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] The patch for XSA-392 introduced another issue which might result in a deadlock when trying to free the SKB of a packet dropped due to the XSA-392 handling (CVE-2022-42328). Additionally when dropping packages for other reasons the same deadlock could occur in case of netpoll being active for the interface the xen-netback driver is connected to (CVE-2022-42329).
In the Linux kernel, the following vulnerability has been resolved: fsdax: Fix infinite loop in dax_iomap_rw() I got an infinite loop and a WARNING report when executing a tail command in virtiofs. WARNING: CPU: 10 PID: 964 at fs/iomap/iter.c:34 iomap_iter+0x3a2/0x3d0 Modules linked in: CPU: 10 PID: 964 Comm: tail Not tainted 5.19.0-rc7 Call Trace: <TASK> dax_iomap_rw+0xea/0x620 ? __this_cpu_preempt_check+0x13/0x20 fuse_dax_read_iter+0x47/0x80 fuse_file_read_iter+0xae/0xd0 new_sync_read+0xfe/0x180 ? 0xffffffff81000000 vfs_read+0x14d/0x1a0 ksys_read+0x6d/0xf0 __x64_sys_read+0x1a/0x20 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd The tail command will call read() with a count of 0. In this case, iomap_iter() will report this WARNING, and always return 1 which casuing the infinite loop in dax_iomap_rw(). Fixing by checking count whether is 0 in dax_iomap_rw().
In the Linux kernel, the following vulnerability has been resolved: net: ks8851: Queue RX packets in IRQ handler instead of disabling BHs Currently the driver uses local_bh_disable()/local_bh_enable() in its IRQ handler to avoid triggering net_rx_action() softirq on exit from netif_rx(). The net_rx_action() could trigger this driver .start_xmit callback, which is protected by the same lock as the IRQ handler, so calling the .start_xmit from netif_rx() from the IRQ handler critical section protected by the lock could lead to an attempt to claim the already claimed lock, and a hang. The local_bh_disable()/local_bh_enable() approach works only in case the IRQ handler is protected by a spinlock, but does not work if the IRQ handler is protected by mutex, i.e. this works for KS8851 with Parallel bus interface, but not for KS8851 with SPI bus interface. Remove the BH manipulation and instead of calling netif_rx() inside the IRQ handler code protected by the lock, queue all the received SKBs in the IRQ handler into a queue first, and once the IRQ handler exits the critical section protected by the lock, dequeue all the queued SKBs and push them all into netif_rx(). At this point, it is safe to trigger the net_rx_action() softirq, since the netif_rx() call is outside of the lock that protects the IRQ handler.
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Prevent crash when disable stream [Why] Disabling stream encoder invokes a function that no longer exists. [How] Check if the function declaration is NULL in disable stream encoder.
In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: fix reference counting on zcrypt card objects Tests with hot-plugging crytpo cards on KVM guests with debug kernel build revealed an use after free for the load field of the struct zcrypt_card. The reason was an incorrect reference handling of the zcrypt card object which could lead to a free of the zcrypt card object while it was still in use. This is an example of the slab message: kernel: 0x00000000885a7512-0x00000000885a7513 @offset=1298. First byte 0x68 instead of 0x6b kernel: Allocated in zcrypt_card_alloc+0x36/0x70 [zcrypt] age=18046 cpu=3 pid=43 kernel: kmalloc_trace+0x3f2/0x470 kernel: zcrypt_card_alloc+0x36/0x70 [zcrypt] kernel: zcrypt_cex4_card_probe+0x26/0x380 [zcrypt_cex4] kernel: ap_device_probe+0x15c/0x290 kernel: really_probe+0xd2/0x468 kernel: driver_probe_device+0x40/0xf0 kernel: __device_attach_driver+0xc0/0x140 kernel: bus_for_each_drv+0x8c/0xd0 kernel: __device_attach+0x114/0x198 kernel: bus_probe_device+0xb4/0xc8 kernel: device_add+0x4d2/0x6e0 kernel: ap_scan_adapter+0x3d0/0x7c0 kernel: ap_scan_bus+0x5a/0x3b0 kernel: ap_scan_bus_wq_callback+0x40/0x60 kernel: process_one_work+0x26e/0x620 kernel: worker_thread+0x21c/0x440 kernel: Freed in zcrypt_card_put+0x54/0x80 [zcrypt] age=9024 cpu=3 pid=43 kernel: kfree+0x37e/0x418 kernel: zcrypt_card_put+0x54/0x80 [zcrypt] kernel: ap_device_remove+0x4c/0xe0 kernel: device_release_driver_internal+0x1c4/0x270 kernel: bus_remove_device+0x100/0x188 kernel: device_del+0x164/0x3c0 kernel: device_unregister+0x30/0x90 kernel: ap_scan_adapter+0xc8/0x7c0 kernel: ap_scan_bus+0x5a/0x3b0 kernel: ap_scan_bus_wq_callback+0x40/0x60 kernel: process_one_work+0x26e/0x620 kernel: worker_thread+0x21c/0x440 kernel: kthread+0x150/0x168 kernel: __ret_from_fork+0x3c/0x58 kernel: ret_from_fork+0xa/0x30 kernel: Slab 0x00000372022169c0 objects=20 used=18 fp=0x00000000885a7c88 flags=0x3ffff00000000a00(workingset|slab|node=0|zone=1|lastcpupid=0x1ffff) kernel: Object 0x00000000885a74b8 @offset=1208 fp=0x00000000885a7c88 kernel: Redzone 00000000885a74b0: bb bb bb bb bb bb bb bb ........ kernel: Object 00000000885a74b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74f8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a7508: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 68 4b 6b 6b 6b a5 kkkkkkkkkkhKkkk. kernel: Redzone 00000000885a7518: bb bb bb bb bb bb bb bb ........ kernel: Padding 00000000885a756c: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ kernel: CPU: 0 PID: 387 Comm: systemd-udevd Not tainted 6.8.0-HF #2 kernel: Hardware name: IBM 3931 A01 704 (KVM/Linux) kernel: Call Trace: kernel: [<00000000ca5ab5b8>] dump_stack_lvl+0x90/0x120 kernel: [<00000000c99d78bc>] check_bytes_and_report+0x114/0x140 kernel: [<00000000c99d53cc>] check_object+0x334/0x3f8 kernel: [<00000000c99d820c>] alloc_debug_processing+0xc4/0x1f8 kernel: [<00000000c99d852e>] get_partial_node.part.0+0x1ee/0x3e0 kernel: [<00000000c99d94ec>] ___slab_alloc+0xaf4/0x13c8 kernel: [<00000000c99d9e38>] __slab_alloc.constprop.0+0x78/0xb8 kernel: [<00000000c99dc8dc>] __kmalloc+0x434/0x590 kernel: [<00000000c9b4c0ce>] ext4_htree_store_dirent+0x4e/0x1c0 kernel: [<00000000c9b908a2>] htree_dirblock_to_tree+0x17a/0x3f0 kernel: ---truncated---
In the Linux kernel, the following vulnerability has been resolved: tcp: Fix Use-After-Free in tcp_ao_connect_init Since call_rcu, which is called in the hlist_for_each_entry_rcu traversal of tcp_ao_connect_init, is not part of the RCU read critical section, it is possible that the RCU grace period will pass during the traversal and the key will be free. To prevent this, it should be changed to hlist_for_each_entry_safe.
In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7925e: fix use-after-free in free_irq() From commit a304e1b82808 ("[PATCH] Debug shared irqs"), there is a test to make sure the shared irq handler should be able to handle the unexpected event after deregistration. For this case, let's apply MT76_REMOVED flag to indicate the device was removed and do not run into the resource access anymore.
In the Linux kernel, the following vulnerability has been resolved: media: edia: dvbdev: fix a use-after-free In dvb_register_device, *pdvbdev is set equal to dvbdev, which is freed in several error-handling paths. However, *pdvbdev is not set to NULL after dvbdev's deallocation, causing use-after-frees in many places, for example, in the following call chain: budget_register |-> dvb_dmxdev_init |-> dvb_register_device |-> dvb_dmxdev_release |-> dvb_unregister_device |-> dvb_remove_device |-> dvb_device_put |-> kref_put When calling dvb_unregister_device, dmxdev->dvbdev (i.e. *pdvbdev in dvb_register_device) could point to memory that had been freed in dvb_register_device. Thereafter, this pointer is transferred to kref_put and triggering a use-after-free.
Use After Free vulnerability in Linux kernel traffic control index filter (tcindex) allows Privilege Escalation. The imperfect hash area can be updated while packets are traversing, which will cause a use-after-free when 'tcf_exts_exec()' is called with the destroyed tcf_ext. A local attacker user can use this vulnerability to elevate its privileges to root. This issue affects Linux Kernel: from 4.14 before git commit ee059170b1f7e94e55fa6cadee544e176a6e59c2.
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix fortify source warning while accessing Eth segment ------------[ cut here ]------------ memcpy: detected field-spanning write (size 56) of single field "eseg->inline_hdr.start" at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 (size 2) WARNING: CPU: 0 PID: 293779 at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Modules linked in: 8021q garp mrp stp llc rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) ib_umad(OE) mlx5_ib(OE) ib_uverbs(OE) ib_core(OE) mlx5_core(OE) pci_hyperv_intf mlxdevm(OE) mlx_compat(OE) tls mlxfw(OE) psample 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_ipv6 nf_defrag_ipv4 ip_set nf_tables libcrc32c nfnetlink mst_pciconf(OE) knem(OE) vfio_pci vfio_pci_core vfio_iommu_type1 vfio iommufd irqbypass cuse nfsv3 nfs fscache netfs xfrm_user xfrm_algo ipmi_devintf ipmi_msghandler binfmt_misc crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic ghash_clmulni_intel sha512_ssse3 snd_pcsp aesni_intel crypto_simd cryptd snd_pcm snd_timer joydev snd soundcore input_leds serio_raw evbug nfsd auth_rpcgss nfs_acl lockd grace sch_fq_codel sunrpc drm efi_pstore ip_tables x_tables autofs4 psmouse virtio_net net_failover failover floppy [last unloaded: mlx_compat(OE)] CPU: 0 PID: 293779 Comm: ssh Tainted: G OE 6.2.0-32-generic #32~22.04.1-Ubuntu Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Code: 0c 01 00 a8 01 75 25 48 8b 75 a0 b9 02 00 00 00 48 c7 c2 10 5b fd c0 48 c7 c7 80 5b fd c0 c6 05 57 0c 03 00 01 e8 95 4d 93 da <0f> 0b 44 8b 4d b0 4c 8b 45 c8 48 8b 4d c0 e9 49 fb ff ff 41 0f b7 RSP: 0018:ffffb5b48478b570 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffb5b48478b628 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffb5b48478b5e8 R13: ffff963a3c609b5e R14: ffff9639c3fbd800 R15: ffffb5b480475a80 FS: 00007fc03b444c80(0000) GS:ffff963a3dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556f46bdf000 CR3: 0000000006ac6003 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? show_regs+0x72/0x90 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? __warn+0x8d/0x160 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? report_bug+0x1bb/0x1d0 ? handle_bug+0x46/0x90 ? exc_invalid_op+0x19/0x80 ? asm_exc_invalid_op+0x1b/0x20 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] mlx5_ib_post_send_nodrain+0xb/0x20 [mlx5_ib] ipoib_send+0x2ec/0x770 [ib_ipoib] ipoib_start_xmit+0x5a0/0x770 [ib_ipoib] dev_hard_start_xmit+0x8e/0x1e0 ? validate_xmit_skb_list+0x4d/0x80 sch_direct_xmit+0x116/0x3a0 __dev_xmit_skb+0x1fd/0x580 __dev_queue_xmit+0x284/0x6b0 ? _raw_spin_unlock_irq+0xe/0x50 ? __flush_work.isra.0+0x20d/0x370 ? push_pseudo_header+0x17/0x40 [ib_ipoib] neigh_connected_output+0xcd/0x110 ip_finish_output2+0x179/0x480 ? __smp_call_single_queue+0x61/0xa0 __ip_finish_output+0xc3/0x190 ip_finish_output+0x2e/0xf0 ip_output+0x78/0x110 ? __pfx_ip_finish_output+0x10/0x10 ip_local_out+0x64/0x70 __ip_queue_xmit+0x18a/0x460 ip_queue_xmit+0x15/0x30 __tcp_transmit_skb+0x914/0x9c0 tcp_write_xmit+0x334/0x8d0 tcp_push_one+0x3c/0x60 tcp_sendmsg_locked+0x2e1/0xac0 tcp_sendmsg+0x2d/0x50 inet_sendmsg+0x43/0x90 sock_sendmsg+0x68/0x80 sock_write_iter+0x93/0x100 vfs_write+0x326/0x3c0 ksys_write+0xbd/0xf0 ? do_syscall_64+0x69/0x90 __x64_sys_write+0x19/0x30 do_syscall_ ---truncated---
A use-after-free vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation. The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered. We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.
A use-after-free vulnerability in the Linux Kernel traffic control index filter (tcindex) can be exploited to achieve local privilege escalation. The tcindex_delete function which does not properly deactivate filters in case of a perfect hashes while deleting the underlying structure which can later lead to double freeing the structure. A local attacker user can use this vulnerability to elevate its privileges to root. We recommend upgrading past commit 8c710f75256bb3cf05ac7b1672c82b92c43f3d28.
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault syzbot reports a f2fs bug as below: BUG: KASAN: slab-use-after-free in f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 Read of size 8 at addr ffff88807bb22680 by task syz-executor184/5058 CPU: 0 PID: 5058 Comm: syz-executor184 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x163/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x170 mm/kasan/report.c:601 f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 __do_fault+0x131/0x450 mm/memory.c:4376 do_shared_fault mm/memory.c:4798 [inline] do_fault mm/memory.c:4872 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5144 [inline] __handle_mm_fault+0x23b7/0x72b0 mm/memory.c:5285 handle_mm_fault+0x27e/0x770 mm/memory.c:5450 do_user_addr_fault arch/x86/mm/fault.c:1364 [inline] handle_page_fault arch/x86/mm/fault.c:1507 [inline] exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1563 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 The root cause is: in f2fs_filemap_fault(), vmf->vma may be not alive after filemap_fault(), so it may cause use-after-free issue when accessing vmf->vma->vm_flags in trace_f2fs_filemap_fault(). So it needs to keep vm_flags in separated temporary variable for tracepoint use.
In the Linux kernel, the following vulnerability has been resolved: crypto: qat - resolve race condition during AER recovery During the PCI AER system's error recovery process, the kernel driver may encounter a race condition with freeing the reset_data structure's memory. If the device restart will take more than 10 seconds the function scheduling that restart will exit due to a timeout, and the reset_data structure will be freed. However, this data structure is used for completion notification after the restart is completed, which leads to a UAF bug. This results in a KFENCE bug notice. BUG: KFENCE: use-after-free read in adf_device_reset_worker+0x38/0xa0 [intel_qat] Use-after-free read at 0x00000000bc56fddf (in kfence-#142): adf_device_reset_worker+0x38/0xa0 [intel_qat] process_one_work+0x173/0x340 To resolve this race condition, the memory associated to the container of the work_struct is freed on the worker if the timeout expired, otherwise on the function that schedules the worker. The timeout detection can be done by checking if the caller is still waiting for completion or not by using completion_done() function.
In the Linux kernel, the following vulnerability has been resolved: mac802154: fix llsec key resources release in mac802154_llsec_key_del mac802154_llsec_key_del() can free resources of a key directly without following the RCU rules for waiting before the end of a grace period. This may lead to use-after-free in case llsec_lookup_key() is traversing the list of keys in parallel with a key deletion: refcount_t: addition on 0; use-after-free. WARNING: CPU: 4 PID: 16000 at lib/refcount.c:25 refcount_warn_saturate+0x162/0x2a0 Modules linked in: CPU: 4 PID: 16000 Comm: wpan-ping Not tainted 6.7.0 #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:refcount_warn_saturate+0x162/0x2a0 Call Trace: <TASK> llsec_lookup_key.isra.0+0x890/0x9e0 mac802154_llsec_encrypt+0x30c/0x9c0 ieee802154_subif_start_xmit+0x24/0x1e0 dev_hard_start_xmit+0x13e/0x690 sch_direct_xmit+0x2ae/0xbc0 __dev_queue_xmit+0x11dd/0x3c20 dgram_sendmsg+0x90b/0xd60 __sys_sendto+0x466/0x4c0 __x64_sys_sendto+0xe0/0x1c0 do_syscall_64+0x45/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Also, ieee802154_llsec_key_entry structures are not freed by mac802154_llsec_key_del(): unreferenced object 0xffff8880613b6980 (size 64): comm "iwpan", pid 2176, jiffies 4294761134 (age 60.475s) hex dump (first 32 bytes): 78 0d 8f 18 80 88 ff ff 22 01 00 00 00 00 ad de x......."....... 00 00 00 00 00 00 00 00 03 00 cd ab 00 00 00 00 ................ backtrace: [<ffffffff81dcfa62>] __kmem_cache_alloc_node+0x1e2/0x2d0 [<ffffffff81c43865>] kmalloc_trace+0x25/0xc0 [<ffffffff88968b09>] mac802154_llsec_key_add+0xac9/0xcf0 [<ffffffff8896e41a>] ieee802154_add_llsec_key+0x5a/0x80 [<ffffffff8892adc6>] nl802154_add_llsec_key+0x426/0x5b0 [<ffffffff86ff293e>] genl_family_rcv_msg_doit+0x1fe/0x2f0 [<ffffffff86ff46d1>] genl_rcv_msg+0x531/0x7d0 [<ffffffff86fee7a9>] netlink_rcv_skb+0x169/0x440 [<ffffffff86ff1d88>] genl_rcv+0x28/0x40 [<ffffffff86fec15c>] netlink_unicast+0x53c/0x820 [<ffffffff86fecd8b>] netlink_sendmsg+0x93b/0xe60 [<ffffffff86b91b35>] ____sys_sendmsg+0xac5/0xca0 [<ffffffff86b9c3dd>] ___sys_sendmsg+0x11d/0x1c0 [<ffffffff86b9c65a>] __sys_sendmsg+0xfa/0x1d0 [<ffffffff88eadbf5>] do_syscall_64+0x45/0xf0 [<ffffffff890000ea>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 Handle the proper resource release in the RCU callback function mac802154_llsec_key_del_rcu(). Note that if llsec_lookup_key() finds a key, it gets a refcount via llsec_key_get() and locally copies key id from key_entry (which is a list element). So it's safe to call llsec_key_put() and free the list entry after the RCU grace period elapses. Found by Linux Verification Center (linuxtesting.org).
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error When ncm function is working and then stop usb0 interface for link down, eth_stop() is called. At this piont, accidentally if usb transport error should happen in usb_ep_enable(), 'in_ep' and/or 'out_ep' may not be enabled. After that, ncm_disable() is called to disable for ncm unbind but gether_disconnect() is never called since 'in_ep' is not enabled. As the result, ncm object is released in ncm unbind but 'dev->port_usb' associated to 'ncm->port' is not NULL. And when ncm bind again to recover netdev, ncm object is reallocated but usb0 interface is already associated to previous released ncm object. Therefore, once usb0 interface is up and eth_start_xmit() is called, released ncm object is dereferrenced and it might cause use-after-free memory. [function unlink via configfs] usb0: eth_stop dev->port_usb=ffffff9b179c3200 --> error happens in usb_ep_enable(). NCM: ncm_disable: ncm=ffffff9b179c3200 --> no gether_disconnect() since ncm->port.in_ep->enabled is false. NCM: ncm_unbind: ncm unbind ncm=ffffff9b179c3200 NCM: ncm_free: ncm free ncm=ffffff9b179c3200 <-- released ncm [function link via configfs] NCM: ncm_alloc: ncm alloc ncm=ffffff9ac4f8a000 NCM: ncm_bind: ncm bind ncm=ffffff9ac4f8a000 NCM: ncm_set_alt: ncm=ffffff9ac4f8a000 alt=0 usb0: eth_open dev->port_usb=ffffff9b179c3200 <-- previous released ncm usb0: eth_start dev->port_usb=ffffff9b179c3200 <-- eth_start_xmit() --> dev->wrap() Unable to handle kernel paging request at virtual address dead00000000014f This patch addresses the issue by checking if 'ncm->netdev' is not NULL at ncm_disable() to call gether_disconnect() to deassociate 'dev->port_usb'. It's more reasonable to check 'ncm->netdev' to call gether_connect/disconnect rather than check 'ncm->port.in_ep->enabled' since it might not be enabled but the gether connection might be established.
In the Linux kernel, the following vulnerability has been resolved: bootconfig: use memblock_free_late to free xbc memory to buddy On the time to free xbc memory in xbc_exit(), memblock may has handed over memory to buddy allocator. So it doesn't make sense to free memory back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86. Following KASAN logs shows this case. This patch fixes the xbc memory free problem by calling memblock_free() in early xbc init error rewind path and calling memblock_free_late() in xbc exit path to free memory to buddy allocator. [ 9.410890] ================================================================== [ 9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260 [ 9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1 [ 9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G U 6.9.0-rc3-00208-g586b5dfb51b9 #5 [ 9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023 [ 9.460789] Call Trace: [ 9.463518] <TASK> [ 9.465859] dump_stack_lvl+0x53/0x70 [ 9.469949] print_report+0xce/0x610 [ 9.473944] ? __virt_addr_valid+0xf5/0x1b0 [ 9.478619] ? memblock_isolate_range+0x12d/0x260 [ 9.483877] kasan_report+0xc6/0x100 [ 9.487870] ? memblock_isolate_range+0x12d/0x260 [ 9.493125] memblock_isolate_range+0x12d/0x260 [ 9.498187] memblock_phys_free+0xb4/0x160 [ 9.502762] ? __pfx_memblock_phys_free+0x10/0x10 [ 9.508021] ? mutex_unlock+0x7e/0xd0 [ 9.512111] ? __pfx_mutex_unlock+0x10/0x10 [ 9.516786] ? kernel_init_freeable+0x2d4/0x430 [ 9.521850] ? __pfx_kernel_init+0x10/0x10 [ 9.526426] xbc_exit+0x17/0x70 [ 9.529935] kernel_init+0x38/0x1e0 [ 9.533829] ? _raw_spin_unlock_irq+0xd/0x30 [ 9.538601] ret_from_fork+0x2c/0x50 [ 9.542596] ? __pfx_kernel_init+0x10/0x10 [ 9.547170] ret_from_fork_asm+0x1a/0x30 [ 9.551552] </TASK> [ 9.555649] The buggy address belongs to the physical page: [ 9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30 [ 9.570821] flags: 0x200000000000000(node=0|zone=2) [ 9.576271] page_type: 0xffffffff() [ 9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000 [ 9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 [ 9.597476] page dumped because: kasan: bad access detected [ 9.605362] Memory state around the buggy address: [ 9.610714] ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.618786] ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.634930] ^ [ 9.638534] ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.646605] ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.654675] ==================================================================
In the Linux kernel, the following vulnerability has been resolved: soc: qcom: pmic_glink_altmode: fix drm bridge use-after-free A recent DRM series purporting to simplify support for "transparent bridges" and handling of probe deferrals ironically exposed a use-after-free issue on pmic_glink_altmode probe deferral. This has manifested itself as the display subsystem occasionally failing to initialise and NULL-pointer dereferences during boot of machines like the Lenovo ThinkPad X13s. Specifically, the dp-hpd bridge is currently registered before all resources have been acquired which means that it can also be deregistered on probe deferrals. In the meantime there is a race window where the new aux bridge driver (or PHY driver previously) may have looked up the dp-hpd bridge and stored a (non-reference-counted) pointer to the bridge which is about to be deallocated. When the display controller is later initialised, this triggers a use-after-free when attaching the bridges: dp -> aux -> dp-hpd (freed) which may, for example, result in the freed bridge failing to attach: [drm:drm_bridge_attach [drm]] *ERROR* failed to attach bridge /soc@0/phy@88eb000 to encoder TMDS-31: -16 or a NULL-pointer dereference: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ... Call trace: drm_bridge_attach+0x70/0x1a8 [drm] drm_aux_bridge_attach+0x24/0x38 [aux_bridge] drm_bridge_attach+0x80/0x1a8 [drm] dp_bridge_init+0xa8/0x15c [msm] msm_dp_modeset_init+0x28/0xc4 [msm] The DRM bridge implementation is clearly fragile and implicitly built on the assumption that bridges may never go away. In this case, the fix is to move the bridge registration in the pmic_glink_altmode driver to after all resources have been looked up. Incidentally, with the new dp-hpd bridge implementation, which registers child devices, this is also a requirement due to a long-standing issue in driver core that can otherwise lead to a probe deferral loop (see commit fbc35b45f9f6 ("Add documentation on meaning of -EPROBE_DEFER")). [DB: slightly fixed commit message by adding the word 'commit']
A use after free vulnerability exists in the ALSA PCM package in the Linux Kernel. SNDRV_CTL_IOCTL_ELEM_{READ|WRITE}32 is missing locks that can be used in a use-after-free that can result in a priviledge escalation to gain ring0 access from the system user. We recommend upgrading past commit 56b88b50565cd8b946a2d00b0c83927b7ebb055e
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in cifs_debug_files_proc_show() Skip sessions that are being teared down (status == SES_EXITING) to avoid UAF.
There is a logic error in io_uring's implementation which can be used to trigger a use-after-free vulnerability leading to privilege escalation. In the io_prep_async_work function the assumption that the last io_grab_identity call cannot return false is not true, and in this case the function will use the init_cred or the previous linked requests identity to do operations instead of using the current identity. This can lead to reference counting issues causing use-after-free. We recommend upgrading past version 5.10.161.
In the Linux kernel, the following vulnerability has been resolved: tls: fix use-after-free on failed backlog decryption When the decrypt request goes to the backlog and crypto_aead_decrypt returns -EBUSY, tls_do_decryption will wait until all async decryptions have completed. If one of them fails, tls_do_decryption will return -EBADMSG and tls_decrypt_sg jumps to the error path, releasing all the pages. But the pages have been passed to the async callback, and have already been released by tls_decrypt_done. The only true async case is when crypto_aead_decrypt returns -EINPROGRESS. With -EBUSY, we already waited so we can tell tls_sw_recvmsg that the data is available for immediate copy, but we need to notify tls_decrypt_sg (via the new ->async_done flag) that the memory has already been released.
In the Linux kernel, the following vulnerability has been resolved: riscv: Fix module loading free order Reverse order of kfree calls to resolve use-after-free error.
In the Linux kernel, the following vulnerability has been resolved: ceph: prevent use-after-free in encode_cap_msg() In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed. In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it. encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent "use after free" error.
In the Linux kernel, the following vulnerability has been resolved: spi: lpspi: Avoid potential use-after-free in probe() fsl_lpspi_probe() is allocating/disposing memory manually with spi_alloc_host()/spi_alloc_target(), but uses devm_spi_register_controller(). In case of error after the latter call the memory will be explicitly freed in the probe function by spi_controller_put() call, but used afterwards by "devm" management outside probe() (spi_unregister_controller() <- devm_spi_unregister() below). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070 ... Call trace: kernfs_find_ns kernfs_find_and_get_ns sysfs_remove_group sysfs_remove_groups device_remove_attrs device_del spi_unregister_controller devm_spi_unregister release_nodes devres_release_all really_probe driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache There is a potential UAF scenario in the case of an LPI translation cache hit racing with an operation that invalidates the cache, such as a DISCARD ITS command. The root of the problem is that vgic_its_check_cache() does not elevate the refcount on the vgic_irq before dropping the lock that serializes refcount changes. Have vgic_its_check_cache() raise the refcount on the returned vgic_irq and add the corresponding decrement after queueing the interrupt.
In the Linux kernel, the following vulnerability has been resolved: ALSA: sh: aica: reorder cleanup operations to avoid UAF bugs The dreamcastcard->timer could schedule the spu_dma_work and the spu_dma_work could also arm the dreamcastcard->timer. When the snd_pcm_substream is closing, the aica_channel will be deallocated. But it could still be dereferenced in the worker thread. The reason is that del_timer() will return directly regardless of whether the timer handler is running or not and the worker could be rescheduled in the timer handler. As a result, the UAF bug will happen. The racy situation is shown below: (Thread 1) | (Thread 2) snd_aicapcm_pcm_close() | ... | run_spu_dma() //worker | mod_timer() flush_work() | del_timer() | aica_period_elapsed() //timer kfree(dreamcastcard->channel) | schedule_work() | run_spu_dma() //worker ... | dreamcastcard->channel-> //USE In order to mitigate this bug and other possible corner cases, call mod_timer() conditionally in run_spu_dma(), then implement PCM sync_stop op to cancel both the timer and worker. The sync_stop op will be called from PCM core appropriately when needed.