In the Linux kernel, the following vulnerability has been resolved: zloop: fix KASAN use-after-free of tag set When a zoned loop device, or zloop device, is removed, KASAN enabled kernel reports "BUG KASAN use-after-free" in blk_mq_free_tag_set(). The BUG happens because zloop_ctl_remove() calls put_disk(), which invokes zloop_free_disk(). The zloop_free_disk() frees the memory allocated for the zlo pointer. However, after the memory is freed, zloop_ctl_remove() calls blk_mq_free_tag_set(&zlo->tag_set), which accesses the freed zlo. Hence the KASAN use-after-free. zloop_ctl_remove() put_disk(zlo->disk) put_device() kobject_put() ... zloop_free_disk() kvfree(zlo) blk_mq_free_tag_set(&zlo->tag_set) To avoid the BUG, move the call to blk_mq_free_tag_set(&zlo->tag_set) from zloop_ctl_remove() into zloop_free_disk(). This ensures that the tag_set is freed before the call to kvfree(zlo).
In the Linux kernel, the following vulnerability has been resolved: drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req() While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req(). Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it's used. v2: Fix kfreeing the request if getting an mst_primary reference fails.
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in decryption with multichannel After commit f7025d861694 ("smb: client: allocate crypto only for primary server") and commit b0abcd65ec54 ("smb: client: fix UAF in async decryption"), the channels started reusing AEAD TFM from primary channel to perform synchronous decryption, but that can't done as there could be multiple cifsd threads (one per channel) simultaneously accessing it to perform decryption. This fixes the following KASAN splat when running fstest generic/249 with 'vers=3.1.1,multichannel,max_channels=4,seal' against Windows Server 2022: BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xba/0x110 Read of size 8 at addr ffff8881046c18a0 by task cifsd/986 CPU: 3 UID: 0 PID: 986 Comm: cifsd Not tainted 6.15.0-rc1 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 print_report+0x156/0x528 ? gf128mul_4k_lle+0xba/0x110 ? __virt_addr_valid+0x145/0x300 ? __phys_addr+0x46/0x90 ? gf128mul_4k_lle+0xba/0x110 kasan_report+0xdf/0x1a0 ? gf128mul_4k_lle+0xba/0x110 gf128mul_4k_lle+0xba/0x110 ghash_update+0x189/0x210 shash_ahash_update+0x295/0x370 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_extract_iter_to_sg+0x10/0x10 ? ___kmalloc_large_node+0x10e/0x180 ? __asan_memset+0x23/0x50 crypto_ahash_update+0x3c/0xc0 gcm_hash_assoc_remain_continue+0x93/0xc0 crypt_message+0xe09/0xec0 [cifs] ? __pfx_crypt_message+0x10/0x10 [cifs] ? _raw_spin_unlock+0x23/0x40 ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs] decrypt_raw_data+0x229/0x380 [cifs] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs] ? __pfx_cifs_read_iter_from_socket+0x10/0x10 [cifs] smb3_receive_transform+0x837/0xc80 [cifs] ? __pfx_smb3_receive_transform+0x10/0x10 [cifs] ? __pfx___might_resched+0x10/0x10 ? __pfx_smb3_is_transform_hdr+0x10/0x10 [cifs] cifs_demultiplex_thread+0x692/0x1570 [cifs] ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] ? rcu_is_watching+0x20/0x50 ? rcu_lockdep_current_cpu_online+0x62/0xb0 ? find_held_lock+0x32/0x90 ? kvm_sched_clock_read+0x11/0x20 ? local_clock_noinstr+0xd/0xd0 ? trace_irq_enable.constprop.0+0xa8/0xe0 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] kthread+0x1fe/0x380 ? kthread+0x10f/0x380 ? __pfx_kthread+0x10/0x10 ? local_clock_noinstr+0xd/0xd0 ? ret_from_fork+0x1b/0x60 ? local_clock+0x15/0x30 ? lock_release+0x29b/0x390 ? rcu_is_watching+0x20/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK>
In the Linux kernel, the following vulnerability has been resolved: btrfs: always report error in run_one_delayed_ref() Currently we have a btrfs_debug() for run_one_delayed_ref() failure, but if end users hit such problem, there will be no chance that btrfs_debug() is enabled. This can lead to very little useful info for debugging. This patch will: - Add extra info for error reporting Including: * logical bytenr * num_bytes * type * action * ref_mod - Replace the btrfs_debug() with btrfs_err() - Move the error reporting into run_one_delayed_ref() This is to avoid use-after-free, the @node can be freed in the caller. This error should only be triggered at most once. As if run_one_delayed_ref() failed, we trigger the error message, then causing the call chain to error out: btrfs_run_delayed_refs() `- btrfs_run_delayed_refs() `- btrfs_run_delayed_refs_for_head() `- run_one_delayed_ref() And we will abort the current transaction in btrfs_run_delayed_refs(). If we have to run delayed refs for the abort transaction, run_one_delayed_ref() will just cleanup the refs and do nothing, thus no new error messages would be output.
In the Linux kernel, the following vulnerability has been resolved: drm: adv7511: Fix use-after-free in adv7533_attach_dsi() The host_node pointer was assigned and freed in adv7533_parse_dt(), and later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put() in error path of probe() and also in the remove().
In the Linux kernel, the following vulnerability has been resolved: tls: separate no-async decryption request handling from async If we're not doing async, the handling is much simpler. There's no reference counting, we just need to wait for the completion to wake us up and return its result. We should preferably also use a separate crypto_wait. I'm not seeing a UAF as I did in the past, I think aec7961916f3 ("tls: fix race between async notify and socket close") took care of it. This will make the next fix easier.
In the Linux kernel, the following vulnerability has been resolved: pps: Fix a use-after-free On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting: pps pps1: removed ------------[ cut here ]------------ kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called. WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150 CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1 Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : kobject_put+0x120/0x150 lr : kobject_put+0x120/0x150 sp : ffffffc0803d3ae0 x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001 x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440 x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600 x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20 x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: kobject_put+0x120/0x150 cdev_put+0x20/0x3c __fput+0x2c4/0x2d8 ____fput+0x1c/0x38 task_work_run+0x70/0xfc do_exit+0x2a0/0x924 do_group_exit+0x34/0x90 get_signal+0x7fc/0x8c0 do_signal+0x128/0x13b4 do_notify_resume+0xdc/0x160 el0_svc+0xd4/0xf8 el0t_64_sync_handler+0x140/0x14c el0t_64_sync+0x190/0x194 ---[ end trace 0000000000000000 ]--- ...followed by more symptoms of corruption, with similar stacks: refcount_t: underflow; use-after-free. kernel BUG at lib/list_debug.c:62! Kernel panic - not syncing: Oops - BUG: Fatal exception This happens because pps_device_destruct() frees the pps_device with the embedded cdev immediately after calling cdev_del(), but, as the comment above cdev_del() notes, fops for previously opened cdevs are still callable even after cdev_del() returns. I think this bug has always been there: I can't explain why it suddenly started happening every time I reboot this particular board. In commit d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source."), George Spelvin suggested removing the embedded cdev. That seems like the simplest way to fix this, so I've implemented his suggestion, using __register_chrdev() with pps_idr becoming the source of truth for which minor corresponds to which device. But now that pps_idr defines userspace visibility instead of cdev_add(), we need to be sure the pps->dev refcount can't reach zero while userspace can still find it again. So, the idr_remove() call moves to pps_unregister_cdev(), and pps_idr now holds a reference to pps->dev. pps_core: source serial1 got cdev (251:1) <...> pps pps1: removed pps_core: unregistering pps1 pps_core: deallocating pps1
In the Linux kernel, the following vulnerability has been resolved: memory: tegra20-emc: fix an OF node reference bug in tegra_emc_find_node_by_ram_code() As of_find_node_by_name() release the reference of the argument device node, tegra_emc_find_node_by_ram_code() releases some device nodes while still in use, resulting in possible UAFs. According to the bindings and the in-tree DTS files, the "emc-tables" node is always device's child node with the property "nvidia,use-ram-code", and the "lpddr2" node is a child of the "emc-tables" node. Thus utilize the for_each_child_of_node() macro and of_get_child_by_name() instead of of_find_node_by_name() to simplify the code. This bug was found by an experimental verification tool that I am developing. [krzysztof: applied v1, adjust the commit msg to incorporate v2 parts]
In the Linux kernel, the following vulnerability has been resolved: PCI/ASPM: Fix link state exit during switch upstream function removal Before 456d8aa37d0f ("PCI/ASPM: Disable ASPM on MFD function removal to avoid use-after-free"), we would free the ASPM link only after the last function on the bus pertaining to the given link was removed. That was too late. If function 0 is removed before sibling function, link->downstream would point to free'd memory after. After above change, we freed the ASPM parent link state upon any function removal on the bus pertaining to a given link. That is too early. If the link is to a PCIe switch with MFD on the upstream port, then removing functions other than 0 first would free a link which still remains parent_link to the remaining downstream ports. The resulting GPFs are especially frequent during hot-unplug, because pciehp removes devices on the link bus in reverse order. On that switch, function 0 is the virtual P2P bridge to the internal bus. Free exactly when function 0 is removed -- before the parent link is obsolete, but after all subordinate links are gone. [kwilczynski: commit log]
Use-after-free vulnerability in the msm_set_crop function in drivers/media/video/msm/msm_camera.c in the MSM-Camera driver for the Linux kernel 3.x, as used in Qualcomm Innovation Center (QuIC) Android contributions for MSM devices and other products, allows attackers to gain privileges or cause a denial of service (memory corruption) via an application that makes a crafted ioctl call.
In the Linux kernel, the following vulnerability has been resolved: media: atomisp: Fix use after free in atomisp_alloc_css_stat_bufs() The "s3a_buf" is freed along with all the other items on the "asd->s3a_stats" list. It leads to a double free and a use after free.
An issue was discovered in the Linux kernel before 5.8.2. fs/io_uring.c has a use-after-free related to io_async_task_func and ctx reference holding, aka CID-6d816e088c35.
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Skip restore TC rules for vport rep without loaded flag During driver unload, unregister_netdev is called after unloading vport rep. So, the mlx5e_rep_priv is already freed while trying to get rpriv->netdev, or walk rpriv->tc_ht, which results in use-after-free. So add the checking to make sure access the data of vport rep which is still loaded.
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject struct_ops registration that uses module ptr and the module btf_id is missing There is a UAF report in the bpf_struct_ops when CONFIG_MODULES=n. In particular, the report is on tcp_congestion_ops that has a "struct module *owner" member. For struct_ops that has a "struct module *owner" member, it can be extended either by the regular kernel module or by the bpf_struct_ops. bpf_try_module_get() will be used to do the refcounting and different refcount is done based on the owner pointer. When CONFIG_MODULES=n, the btf_id of the "struct module" is missing: WARN: resolve_btfids: unresolved symbol module Thus, the bpf_try_module_get() cannot do the correct refcounting. Not all subsystem's struct_ops requires the "struct module *owner" member. e.g. the recent sched_ext_ops. This patch is to disable bpf_struct_ops registration if the struct_ops has the "struct module *" member and the "struct module" btf_id is missing. The btf_type_is_fwd() helper is moved to the btf.h header file for this test. This has happened since the beginning of bpf_struct_ops which has gone through many changes. The Fixes tag is set to a recent commit that this patch can apply cleanly. Considering CONFIG_MODULES=n is not common and the age of the issue, targeting for bpf-next also.
An issue was discovered in the Linux kernel before 5.7. The KVM subsystem allows out-of-range access to memslots after a deletion, aka CID-0774a964ef56. This affects arch/s390/kvm/kvm-s390.c, include/linux/kvm_host.h, and virt/kvm/kvm_main.c.
In the Linux kernel, the following vulnerability has been resolved: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu() Explicitly verify the target vCPU is fully online _prior_ to clamping the index in kvm_get_vcpu(). If the index is "bad", the nospec clamping will generate '0', i.e. KVM will return vCPU0 instead of NULL. In practice, the bug is unlikely to cause problems, as it will only come into play if userspace or the guest is buggy or misbehaving, e.g. KVM may send interrupts to vCPU0 instead of dropping them on the floor. However, returning vCPU0 when it shouldn't exist per online_vcpus is problematic now that KVM uses an xarray for the vCPUs array, as KVM needs to insert into the xarray before publishing the vCPU to userspace (see commit c5b077549136 ("KVM: Convert the kvm->vcpus array to a xarray")), i.e. before vCPU creation is guaranteed to succeed. As a result, incorrectly providing access to vCPU0 will trigger a use-after-free if vCPU0 is dereferenced and kvm_vm_ioctl_create_vcpu() bails out of vCPU creation due to an error and frees vCPU0. Commit afb2acb2e3a3 ("KVM: Fix vcpu_array[0] races") papered over that issue, but in doing so introduced an unsolvable teardown conundrum. Preventing accesses to vCPU0 before it's fully online will allow reverting commit afb2acb2e3a3, without re-introducing the vcpu_array[0] UAF race.
In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Set private->all_drm_private[i]->drm to NULL if mtk_drm_bind returns err The pointer need to be set to NULL, otherwise KASAN complains about use-after-free. Because in mtk_drm_bind, all private's drm are set as follows. private->all_drm_private[i]->drm = drm; And drm will be released by drm_dev_put in case mtk_drm_kms_init returns failure. However, the shutdown path still accesses the previous allocated memory in drm_atomic_helper_shutdown. [ 84.874820] watchdog: watchdog0: watchdog did not stop! [ 86.512054] ================================================================== [ 86.513162] BUG: KASAN: use-after-free in drm_atomic_helper_shutdown+0x33c/0x378 [ 86.514258] Read of size 8 at addr ffff0000d46fc068 by task shutdown/1 [ 86.515213] [ 86.515455] CPU: 1 UID: 0 PID: 1 Comm: shutdown Not tainted 6.13.0-rc1-mtk+gfa1a78e5d24b-dirty #55 [ 86.516752] Hardware name: Unknown Product/Unknown Product, BIOS 2022.10 10/01/2022 [ 86.517960] Call trace: [ 86.518333] show_stack+0x20/0x38 (C) [ 86.518891] dump_stack_lvl+0x90/0xd0 [ 86.519443] print_report+0xf8/0x5b0 [ 86.519985] kasan_report+0xb4/0x100 [ 86.520526] __asan_report_load8_noabort+0x20/0x30 [ 86.521240] drm_atomic_helper_shutdown+0x33c/0x378 [ 86.521966] mtk_drm_shutdown+0x54/0x80 [ 86.522546] platform_shutdown+0x64/0x90 [ 86.523137] device_shutdown+0x260/0x5b8 [ 86.523728] kernel_restart+0x78/0xf0 [ 86.524282] __do_sys_reboot+0x258/0x2f0 [ 86.524871] __arm64_sys_reboot+0x90/0xd8 [ 86.525473] invoke_syscall+0x74/0x268 [ 86.526041] el0_svc_common.constprop.0+0xb0/0x240 [ 86.526751] do_el0_svc+0x4c/0x70 [ 86.527251] el0_svc+0x4c/0xc0 [ 86.527719] el0t_64_sync_handler+0x144/0x168 [ 86.528367] el0t_64_sync+0x198/0x1a0 [ 86.528920] [ 86.529157] The buggy address belongs to the physical page: [ 86.529972] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff0000d46fd4d0 pfn:0x1146fc [ 86.531319] flags: 0xbfffc0000000000(node=0|zone=2|lastcpupid=0xffff) [ 86.532267] raw: 0bfffc0000000000 0000000000000000 dead000000000122 0000000000000000 [ 86.533390] raw: ffff0000d46fd4d0 0000000000000000 00000000ffffffff 0000000000000000 [ 86.534511] page dumped because: kasan: bad access detected [ 86.535323] [ 86.535559] Memory state around the buggy address: [ 86.536265] ffff0000d46fbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.537314] ffff0000d46fbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.538363] >ffff0000d46fc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.544733] ^ [ 86.551057] ffff0000d46fc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.557510] ffff0000d46fc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.563928] ================================================================== [ 86.571093] Disabling lock debugging due to kernel taint [ 86.577642] Unable to handle kernel paging request at virtual address e0e9c0920000000b [ 86.581834] KASAN: maybe wild-memory-access in range [0x0752049000000058-0x075204900000005f] ...
In the Linux kernel, the following vulnerability has been resolved: pds_core: remove write-after-free of client_id A use-after-free error popped up in stress testing: [Mon Apr 21 21:21:33 2025] BUG: KFENCE: use-after-free write in pdsc_auxbus_dev_del+0xef/0x160 [pds_core] [Mon Apr 21 21:21:33 2025] Use-after-free write at 0x000000007013ecd1 (in kfence-#47): [Mon Apr 21 21:21:33 2025] pdsc_auxbus_dev_del+0xef/0x160 [pds_core] [Mon Apr 21 21:21:33 2025] pdsc_remove+0xc0/0x1b0 [pds_core] [Mon Apr 21 21:21:33 2025] pci_device_remove+0x24/0x70 [Mon Apr 21 21:21:33 2025] device_release_driver_internal+0x11f/0x180 [Mon Apr 21 21:21:33 2025] driver_detach+0x45/0x80 [Mon Apr 21 21:21:33 2025] bus_remove_driver+0x83/0xe0 [Mon Apr 21 21:21:33 2025] pci_unregister_driver+0x1a/0x80 The actual device uninit usually happens on a separate thread scheduled after this code runs, but there is no guarantee of order of thread execution, so this could be a problem. There's no actual need to clear the client_id at this point, so simply remove the offending code.
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Forcibly leave SMM mode on SHUTDOWN interception Previously, commit ed129ec9057f ("KVM: x86: forcibly leave nested mode on vCPU reset") addressed an issue where a triple fault occurring in nested mode could lead to use-after-free scenarios. However, the commit did not handle the analogous situation for System Management Mode (SMM). This omission results in triggering a WARN when KVM forces a vCPU INIT after SHUTDOWN interception while the vCPU is in SMM. This situation was reprodused using Syzkaller by: 1) Creating a KVM VM and vCPU 2) Sending a KVM_SMI ioctl to explicitly enter SMM 3) Executing invalid instructions causing consecutive exceptions and eventually a triple fault The issue manifests as follows: WARNING: CPU: 0 PID: 25506 at arch/x86/kvm/x86.c:12112 kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112 Modules linked in: CPU: 0 PID: 25506 Comm: syz-executor.0 Not tainted 6.1.130-syzkaller-00157-g164fe5dde9b6 #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112 Call Trace: <TASK> shutdown_interception+0x66/0xb0 arch/x86/kvm/svm/svm.c:2136 svm_invoke_exit_handler+0x110/0x530 arch/x86/kvm/svm/svm.c:3395 svm_handle_exit+0x424/0x920 arch/x86/kvm/svm/svm.c:3457 vcpu_enter_guest arch/x86/kvm/x86.c:10959 [inline] vcpu_run+0x2c43/0x5a90 arch/x86/kvm/x86.c:11062 kvm_arch_vcpu_ioctl_run+0x50f/0x1cf0 arch/x86/kvm/x86.c:11283 kvm_vcpu_ioctl+0x570/0xf00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4122 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Architecturally, INIT is blocked when the CPU is in SMM, hence KVM's WARN() in kvm_vcpu_reset() to guard against KVM bugs, e.g. to detect improper emulation of INIT. SHUTDOWN on SVM is a weird edge case where KVM needs to do _something_ sane with the VMCB, since it's technically undefined, and INIT is the least awful choice given KVM's ABI. So, double down on stuffing INIT on SHUTDOWN, and force the vCPU out of SMM to avoid any weirdness (and the WARN). Found by Linux Verification Center (linuxtesting.org) with Syzkaller. [sean: massage changelog, make it clear this isn't architectural behavior]
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync This fixes the following crash: ================================================================== BUG: KASAN: slab-use-after-free in mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5543 Read of size 8 at addr ffff88814128f898 by task kworker/u9:4/5961 CPU: 1 UID: 0 PID: 5961 Comm: kworker/u9:4 Not tainted 6.12.0-syzkaller-10684-gf1cd565ce577 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5543 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 16026: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296 remove_adv_monitor+0x102/0x1b0 net/bluetooth/mgmt.c:5568 hci_mgmt_cmd+0xc47/0x11d0 net/bluetooth/hci_sock.c:1712 hci_sock_sendmsg+0x7b8/0x11c0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 sock_write_iter+0x2d7/0x3f0 net/socket.c:1147 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 16022: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x196/0x420 mm/slub.c:4746 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x183/0x430 net/bluetooth/mgmt.c:9550 hci_dev_close_sync+0x6c4/0x11c0 net/bluetooth/hci_sync.c:5208 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:508 sock_do_ioctl+0x158/0x460 net/socket.c:1209 sock_ioctl+0x626/0x8e0 net/socket.c:1328 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f
In the Linux kernel, the following vulnerability has been resolved: wifi: rtlwifi: remove unused check_buddy_priv Commit 2461c7d60f9f ("rtlwifi: Update header file") introduced a global list of private data structures. Later on, commit 26634c4b1868 ("rtlwifi Modify existing bits to match vendor version 2013.02.07") started adding the private data to that list at probe time and added a hook, check_buddy_priv to find the private data from a similar device. However, that function was never used. Besides, though there is a lock for that list, it is never used. And when the probe fails, the private data is never removed from the list. This would cause a second probe to access freed memory. Remove the unused hook, structures and members, which will prevent the potential race condition on the list and its corruption during a second probe when probe fails.
A locking issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_jobctrl.c allows a use-after-free attack against TIOCSPGRP, aka CID-54ffccbf053b.
In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Remove dangling pointers When an async control is written, we copy a pointer to the file handle that started the operation. That pointer will be used when the device is done. Which could be anytime in the future. If the user closes that file descriptor, its structure will be freed, and there will be one dangling pointer per pending async control, that the driver will try to use. Clean all the dangling pointers during release(). To avoid adding a performance penalty in the most common case (no async operation), a counter has been introduced with some logic to make sure that it is properly handled.
In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries/vas: Add close() callback in vas_vm_ops struct The mapping VMA address is saved in VAS window struct when the paste address is mapped. This VMA address is used during migration to unmap the paste address if the window is active. The paste address mapping will be removed when the window is closed or with the munmap(). But the VMA address in the VAS window is not updated with munmap() which is causing invalid access during migration. The KASAN report shows: [16386.254991] BUG: KASAN: slab-use-after-free in reconfig_close_windows+0x1a0/0x4e8 [16386.255043] Read of size 8 at addr c00000014a819670 by task drmgr/696928 [16386.255096] CPU: 29 UID: 0 PID: 696928 Comm: drmgr Kdump: loaded Tainted: G B 6.11.0-rc5-nxgzip #2 [16386.255128] Tainted: [B]=BAD_PAGE [16386.255148] Hardware name: IBM,9080-HEX Power11 (architected) 0x820200 0xf000007 of:IBM,FW1110.00 (NH1110_016) hv:phyp pSeries [16386.255181] Call Trace: [16386.255202] [c00000016b297660] [c0000000018ad0ac] dump_stack_lvl+0x84/0xe8 (unreliable) [16386.255246] [c00000016b297690] [c0000000006e8a90] print_report+0x19c/0x764 [16386.255285] [c00000016b297760] [c0000000006e9490] kasan_report+0x128/0x1f8 [16386.255309] [c00000016b297880] [c0000000006eb5c8] __asan_load8+0xac/0xe0 [16386.255326] [c00000016b2978a0] [c00000000013f898] reconfig_close_windows+0x1a0/0x4e8 [16386.255343] [c00000016b297990] [c000000000140e58] vas_migration_handler+0x3a4/0x3fc [16386.255368] [c00000016b297a90] [c000000000128848] pseries_migrate_partition+0x4c/0x4c4 ... [16386.256136] Allocated by task 696554 on cpu 31 at 16377.277618s: [16386.256149] kasan_save_stack+0x34/0x68 [16386.256163] kasan_save_track+0x34/0x80 [16386.256175] kasan_save_alloc_info+0x58/0x74 [16386.256196] __kasan_slab_alloc+0xb8/0xdc [16386.256209] kmem_cache_alloc_noprof+0x200/0x3d0 [16386.256225] vm_area_alloc+0x44/0x150 [16386.256245] mmap_region+0x214/0x10c4 [16386.256265] do_mmap+0x5fc/0x750 [16386.256277] vm_mmap_pgoff+0x14c/0x24c [16386.256292] ksys_mmap_pgoff+0x20c/0x348 [16386.256303] sys_mmap+0xd0/0x160 ... [16386.256350] Freed by task 0 on cpu 31 at 16386.204848s: [16386.256363] kasan_save_stack+0x34/0x68 [16386.256374] kasan_save_track+0x34/0x80 [16386.256384] kasan_save_free_info+0x64/0x10c [16386.256396] __kasan_slab_free+0x120/0x204 [16386.256415] kmem_cache_free+0x128/0x450 [16386.256428] vm_area_free_rcu_cb+0xa8/0xd8 [16386.256441] rcu_do_batch+0x2c8/0xcf0 [16386.256458] rcu_core+0x378/0x3c4 [16386.256473] handle_softirqs+0x20c/0x60c [16386.256495] do_softirq_own_stack+0x6c/0x88 [16386.256509] do_softirq_own_stack+0x58/0x88 [16386.256521] __irq_exit_rcu+0x1a4/0x20c [16386.256533] irq_exit+0x20/0x38 [16386.256544] interrupt_async_exit_prepare.constprop.0+0x18/0x2c ... [16386.256717] Last potentially related work creation: [16386.256729] kasan_save_stack+0x34/0x68 [16386.256741] __kasan_record_aux_stack+0xcc/0x12c [16386.256753] __call_rcu_common.constprop.0+0x94/0xd04 [16386.256766] vm_area_free+0x28/0x3c [16386.256778] remove_vma+0xf4/0x114 [16386.256797] do_vmi_align_munmap.constprop.0+0x684/0x870 [16386.256811] __vm_munmap+0xe0/0x1f8 [16386.256821] sys_munmap+0x54/0x6c [16386.256830] system_call_exception+0x1a0/0x4a0 [16386.256841] system_call_vectored_common+0x15c/0x2ec [16386.256868] The buggy address belongs to the object at c00000014a819670 which belongs to the cache vm_area_struct of size 168 [16386.256887] The buggy address is located 0 bytes inside of freed 168-byte region [c00000014a819670, c00000014a819718) [16386.256915] The buggy address belongs to the physical page: [16386.256928] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14a81 [16386.256950] memcg:c0000000ba430001 [16386.256961] anon flags: 0x43ffff800000000(node=4|zone=0|lastcpupid=0x7ffff) [16386.256975] page_type: 0xfdffffff(slab) [16386 ---truncated---
In the Linux kernel, the following vulnerability has been resolved: net: ieee802154: do not leave a dangling sk pointer in ieee802154_create() sock_init_data() attaches the allocated sk object to the provided sock object. If ieee802154_create() fails later, the allocated sk object is freed, but the dangling pointer remains in the provided sock object, which may allow use-after-free. Clear the sk pointer in the sock object on error.
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free when COWing tree bock and tracing is enabled When a COWing a tree block, at btrfs_cow_block(), and we have the tracepoint trace_btrfs_cow_block() enabled and preemption is also enabled (CONFIG_PREEMPT=y), we can trigger a use-after-free in the COWed extent buffer while inside the tracepoint code. This is because in some paths that call btrfs_cow_block(), such as btrfs_search_slot(), we are holding the last reference on the extent buffer @buf so btrfs_force_cow_block() drops the last reference on the @buf extent buffer when it calls free_extent_buffer_stale(buf), which schedules the release of the extent buffer with RCU. This means that if we are on a kernel with preemption, the current task may be preempted before calling trace_btrfs_cow_block() and the extent buffer already released by the time trace_btrfs_cow_block() is called, resulting in a use-after-free. Fix this by moving the trace_btrfs_cow_block() from btrfs_cow_block() to btrfs_force_cow_block() before the COWed extent buffer is freed. This also has a side effect of invoking the tracepoint in the tree defrag code, at defrag.c:btrfs_realloc_node(), since btrfs_force_cow_block() is called there, but this is fine and it was actually missing there.
In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix use-after-free in ath12k_dp_cc_cleanup() During ath12k module removal, in ath12k_core_deinit(), ath12k_mac_destroy() un-registers ah->hw from mac80211 and frees the ah->hw as well as all the ar's in it. After this ath12k_core_soc_destroy()-> ath12k_dp_free()-> ath12k_dp_cc_cleanup() tries to access one of the freed ar's from pending skb. This is because during mac destroy, driver failed to flush few data packets, which were accessed later in ath12k_dp_cc_cleanup() and freed, but using ar from the packet led to this use-after-free. BUG: KASAN: use-after-free in ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] Write of size 4 at addr ffff888150bd3514 by task modprobe/8926 CPU: 0 UID: 0 PID: 8926 Comm: modprobe Not tainted 6.11.0-rc2-wt-ath+ #1746 Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021 Call Trace: <TASK> dump_stack_lvl+0x7d/0xe0 print_address_description.constprop.0+0x33/0x3a0 print_report+0xb5/0x260 ? kasan_addr_to_slab+0x24/0x80 kasan_report+0xd8/0x110 ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] kasan_check_range+0xf3/0x1a0 __kasan_check_write+0x14/0x20 ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ath12k_dp_free+0x178/0x420 [ath12k] ath12k_core_stop+0x176/0x200 [ath12k] ath12k_core_deinit+0x13f/0x210 [ath12k] ath12k_pci_remove+0xad/0x1c0 [ath12k] pci_device_remove+0x9b/0x1b0 device_remove+0xbf/0x150 device_release_driver_internal+0x3c3/0x580 ? __kasan_check_read+0x11/0x20 driver_detach+0xc4/0x190 bus_remove_driver+0x130/0x2a0 driver_unregister+0x68/0x90 pci_unregister_driver+0x24/0x240 ? find_module_all+0x13e/0x1e0 ath12k_pci_exit+0x10/0x20 [ath12k] __do_sys_delete_module+0x32c/0x580 ? module_flags+0x2f0/0x2f0 ? kmem_cache_free+0xf0/0x410 ? __fput+0x56f/0xab0 ? __fput+0x56f/0xab0 ? debug_smp_processor_id+0x17/0x20 __x64_sys_delete_module+0x4f/0x70 x64_sys_call+0x522/0x9f0 do_syscall_64+0x64/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f8182c6ac8b Commit 24de1b7b231c ("wifi: ath12k: fix flush failure in recovery scenarios") added the change to decrement the pending packets count in case of recovery which make sense as ah->hw as well all ar's in it are intact during recovery, but during core deinit there is no use in decrementing packets count or waking up the empty waitq as the module is going to be removed also ar's from pending skb's can't be used and the packets should just be released back. To fix this, avoid accessing ar from skb->cb when driver is being unregistered. Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00214-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Fix PCI domain ID release in pci_epc_destroy() pci_epc_destroy() invokes pci_bus_release_domain_nr() to release the PCI domain ID, but there are two issues: - 'epc->dev' is passed to pci_bus_release_domain_nr() which was already freed by device_unregister(), leading to a use-after-free issue. - Domain ID corresponds to the EPC device parent, so passing 'epc->dev' is also wrong. Fix these issues by passing 'epc->dev.parent' to pci_bus_release_domain_nr() and also do it before device_unregister(). [mani: reworded subject and description]
In the Linux kernel, the following vulnerability has been resolved: net: inet: do not leave a dangling sk pointer in inet_create() sock_init_data() attaches the allocated sk object to the provided sock object. If inet_create() fails later, the sk object is freed, but the sock object retains the dangling pointer, which may create use-after-free later. Clear the sk pointer in the sock object on error.
In the Linux kernel, the following vulnerability has been resolved: net: inet6: do not leave a dangling sk pointer in inet6_create() sock_init_data() attaches the allocated sk pointer to the provided sock object. If inet6_create() fails later, the sk object is released, but the sock object retains the dangling sk pointer, which may cause use-after-free later. Clear the sock sk pointer on error.
In the Linux kernel, the following vulnerability has been resolved: Revert "hwmon: (ibmpex) fix use-after-free in high/low store" This reverts commit 6946c726c3f4c36f0f049e6f97e88c510b15f65d. Jean Delvare points out that the patch does not completely fix the reported problem, that it in fact introduces a (new) race condition, and that it may actually not be needed in the first place. Various AI reviews agree. Specific and relevant AI feedback: " This reordering sets the driver data to NULL before removing the sensor attributes in the loop below. ibmpex_show_sensor() retrieves this driver data via dev_get_drvdata() but does not check if it is NULL before dereferencing it to access data->sensors[]. If a userspace process reads a sensor file (like temp1_input) while this delete function is running, could it race with the dev_set_drvdata(..., NULL) call here and crash in ibmpex_show_sensor()? Would it be safer to keep the original order where device_remove_file() is called before clearing the driver data? device_remove_file() should wait for any active sysfs callbacks to complete, which might already prevent the use-after-free this patch intends to fix. " Revert the offending patch. If it can be shown that the originally reported alleged race condition does indeed exist, it can always be re-introduced with a complete fix.
In the Linux kernel, the following vulnerability has been resolved: net: af_can: do not leave a dangling sk pointer in can_create() On error can_create() frees the allocated sk object, but sock_init_data() has already attached it to the provided sock object. This will leave a dangling sk pointer in the sock object and may cause use-after-free later.
A flaw was found in the Linux kernel’s implementation of MIDI, where an attacker with a local account and the permissions to issue ioctl commands to midi devices could trigger a use-after-free issue. A write to this specific memory while freed and before use causes the flow of execution to change and possibly allow for memory corruption or privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix UAF in blkcg_unpin_online() blkcg_unpin_online() walks up the blkcg hierarchy putting the online pin. To walk up, it uses blkcg_parent(blkcg) but it was calling that after blkcg_destroy_blkgs(blkcg) which could free the blkcg, leading to the following UAF: ================================================================== BUG: KASAN: slab-use-after-free in blkcg_unpin_online+0x15a/0x270 Read of size 8 at addr ffff8881057678c0 by task kworker/9:1/117 CPU: 9 UID: 0 PID: 117 Comm: kworker/9:1 Not tainted 6.13.0-rc1-work-00182-gb8f52214c61a-dirty #48 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022 Workqueue: cgwb_release cgwb_release_workfn Call Trace: <TASK> dump_stack_lvl+0x27/0x80 print_report+0x151/0x710 kasan_report+0xc0/0x100 blkcg_unpin_online+0x15a/0x270 cgwb_release_workfn+0x194/0x480 process_scheduled_works+0x71b/0xe20 worker_thread+0x82a/0xbd0 kthread+0x242/0x2c0 ret_from_fork+0x33/0x70 ret_from_fork_asm+0x1a/0x30 </TASK> ... Freed by task 1944: kasan_save_track+0x2b/0x70 kasan_save_free_info+0x3c/0x50 __kasan_slab_free+0x33/0x50 kfree+0x10c/0x330 css_free_rwork_fn+0xe6/0xb30 process_scheduled_works+0x71b/0xe20 worker_thread+0x82a/0xbd0 kthread+0x242/0x2c0 ret_from_fork+0x33/0x70 ret_from_fork_asm+0x1a/0x30 Note that the UAF is not easy to trigger as the free path is indirected behind a couple RCU grace periods and a work item execution. I could only trigger it with artifical msleep() injected in blkcg_unpin_online(). Fix it by reading the parent pointer before destroying the blkcg's blkg's.
In the Linux kernel, the following vulnerability has been resolved: drm: zynqmp_kms: Unplug DRM device before removal Prevent userspace accesses to the DRM device from causing use-after-frees by unplugging the device before we remove it. This causes any further userspace accesses to result in an error without further calls into this driver's internals.
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc() bt_sock_alloc() attaches allocated sk object to the provided sock object. If rfcomm_dlc_alloc() fails, we release the sk object, but leave the dangling pointer in the sock object, which may cause use-after-free. Fix this by swapping calls to bt_sock_alloc() and rfcomm_dlc_alloc().
In the Linux kernel, the following vulnerability has been resolved: btrfs: ref-verify: fix use-after-free after invalid ref action At btrfs_ref_tree_mod() after we successfully inserted the new ref entry (local variable 'ref') into the respective block entry's rbtree (local variable 'be'), if we find an unexpected action of BTRFS_DROP_DELAYED_REF, we error out and free the ref entry without removing it from the block entry's rbtree. Then in the error path of btrfs_ref_tree_mod() we call btrfs_free_ref_cache(), which iterates over all block entries and then calls free_block_entry() for each one, and there we will trigger a use-after-free when we are called against the block entry to which we added the freed ref entry to its rbtree, since the rbtree still points to the block entry, as we didn't remove it from the rbtree before freeing it in the error path at btrfs_ref_tree_mod(). Fix this by removing the new ref entry from the rbtree before freeing it. Syzbot report this with the following stack traces: BTRFS error (device loop0 state EA): Ref action 2, root 5, ref_root 0, parent 8564736, owner 0, offset 0, num_refs 18446744073709551615 __btrfs_mod_ref+0x7dd/0xac0 fs/btrfs/extent-tree.c:2523 update_ref_for_cow+0x9cd/0x11f0 fs/btrfs/ctree.c:512 btrfs_force_cow_block+0x9f6/0x1da0 fs/btrfs/ctree.c:594 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4314 btrfs_insert_empty_item fs/btrfs/ctree.h:669 [inline] btrfs_insert_orphan_item+0x1f1/0x320 fs/btrfs/orphan.c:23 btrfs_orphan_add+0x6d/0x1a0 fs/btrfs/inode.c:3482 btrfs_unlink+0x267/0x350 fs/btrfs/inode.c:4293 vfs_unlink+0x365/0x650 fs/namei.c:4469 do_unlinkat+0x4ae/0x830 fs/namei.c:4533 __do_sys_unlinkat fs/namei.c:4576 [inline] __se_sys_unlinkat fs/namei.c:4569 [inline] __x64_sys_unlinkat+0xcc/0xf0 fs/namei.c:4569 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f BTRFS error (device loop0 state EA): Ref action 1, root 5, ref_root 5, parent 0, owner 260, offset 0, num_refs 1 __btrfs_mod_ref+0x76b/0xac0 fs/btrfs/extent-tree.c:2521 update_ref_for_cow+0x96a/0x11f0 btrfs_force_cow_block+0x9f6/0x1da0 fs/btrfs/ctree.c:594 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_lookup_inode+0xdc/0x480 fs/btrfs/inode-item.c:411 __btrfs_update_delayed_inode+0x1e7/0xb90 fs/btrfs/delayed-inode.c:1030 btrfs_update_delayed_inode fs/btrfs/delayed-inode.c:1114 [inline] __btrfs_commit_inode_delayed_items+0x2318/0x24a0 fs/btrfs/delayed-inode.c:1137 __btrfs_run_delayed_items+0x213/0x490 fs/btrfs/delayed-inode.c:1171 btrfs_commit_transaction+0x8a8/0x3740 fs/btrfs/transaction.c:2313 prepare_to_relocate+0x3c4/0x4c0 fs/btrfs/relocation.c:3586 relocate_block_group+0x16c/0xd40 fs/btrfs/relocation.c:3611 btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4081 btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3377 __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4161 btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4538 BTRFS error (device loop0 state EA): Ref action 2, root 5, ref_root 0, parent 8564736, owner 0, offset 0, num_refs 18446744073709551615 __btrfs_mod_ref+0x7dd/0xac0 fs/btrfs/extent-tree.c:2523 update_ref_for_cow+0x9cd/0x11f0 fs/btrfs/ctree.c:512 btrfs_force_cow_block+0x9f6/0x1da0 fs/btrfs/ctree.c:594 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_lookup_inode+0xdc/0x480 fs/btrfs/inode-item.c:411 __btrfs_update_delayed_inode+0x1e7/0xb90 fs/btrfs/delayed-inode.c:1030 btrfs_update_delayed_i ---truncated---
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix usage slab after free [ +0.000021] BUG: KASAN: slab-use-after-free in drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000027] Read of size 8 at addr ffff8881b8605f88 by task amd_pci_unplug/2147 [ +0.000023] CPU: 6 PID: 2147 Comm: amd_pci_unplug Not tainted 6.10.0+ #1 [ +0.000016] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020 [ +0.000016] Call Trace: [ +0.000008] <TASK> [ +0.000009] dump_stack_lvl+0x76/0xa0 [ +0.000017] print_report+0xce/0x5f0 [ +0.000017] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000019] ? srso_return_thunk+0x5/0x5f [ +0.000015] ? kasan_complete_mode_report_info+0x72/0x200 [ +0.000016] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000019] kasan_report+0xbe/0x110 [ +0.000015] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000023] __asan_report_load8_noabort+0x14/0x30 [ +0.000014] drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000020] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? __kasan_check_write+0x14/0x30 [ +0.000016] ? __pfx_drm_sched_entity_flush+0x10/0x10 [gpu_sched] [ +0.000020] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? __kasan_check_write+0x14/0x30 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? enable_work+0x124/0x220 [ +0.000015] ? __pfx_enable_work+0x10/0x10 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? free_large_kmalloc+0x85/0xf0 [ +0.000016] drm_sched_entity_destroy+0x18/0x30 [gpu_sched] [ +0.000020] amdgpu_vce_sw_fini+0x55/0x170 [amdgpu] [ +0.000735] ? __kasan_check_read+0x11/0x20 [ +0.000016] vce_v4_0_sw_fini+0x80/0x110 [amdgpu] [ +0.000726] amdgpu_device_fini_sw+0x331/0xfc0 [amdgpu] [ +0.000679] ? mutex_unlock+0x80/0xe0 [ +0.000017] ? __pfx_amdgpu_device_fini_sw+0x10/0x10 [amdgpu] [ +0.000662] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? __kasan_check_write+0x14/0x30 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? mutex_unlock+0x80/0xe0 [ +0.000016] amdgpu_driver_release_kms+0x16/0x80 [amdgpu] [ +0.000663] drm_minor_release+0xc9/0x140 [drm] [ +0.000081] drm_release+0x1fd/0x390 [drm] [ +0.000082] __fput+0x36c/0xad0 [ +0.000018] __fput_sync+0x3c/0x50 [ +0.000014] __x64_sys_close+0x7d/0xe0 [ +0.000014] x64_sys_call+0x1bc6/0x2680 [ +0.000014] do_syscall_64+0x70/0x130 [ +0.000014] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? irqentry_exit_to_user_mode+0x60/0x190 [ +0.000015] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? irqentry_exit+0x43/0x50 [ +0.000012] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? exc_page_fault+0x7c/0x110 [ +0.000015] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ +0.000014] RIP: 0033:0x7ffff7b14f67 [ +0.000013] Code: ff e8 0d 16 02 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 73 ba f7 ff [ +0.000026] RSP: 002b:00007fffffffe378 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ +0.000019] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffff7b14f67 [ +0.000014] RDX: 0000000000000000 RSI: 00007ffff7f6f47a RDI: 0000000000000003 [ +0.000014] RBP: 00007fffffffe3a0 R08: 0000555555569890 R09: 0000000000000000 [ +0.000014] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffffffe5c8 [ +0.000013] R13: 00005555555552a9 R14: 0000555555557d48 R15: 00007ffff7ffd040 [ +0.000020] </TASK> [ +0.000016] Allocated by task 383 on cpu 7 at 26.880319s: [ +0.000014] kasan_save_stack+0x28/0x60 [ +0.000008] kasan_save_track+0x18/0x70 [ +0.000007] kasan_save_alloc_info+0x38/0x60 [ +0.000007] __kasan_kmalloc+0xc1/0xd0 [ +0.000007] kmalloc_trace_noprof+0x180/0x380 [ +0.000007] drm_sched_init+0x411/0xec0 [gpu_sched] [ +0.000012] amdgpu_device_init+0x695f/0xa610 [amdgpu] [ +0.000658] amdgpu_driver_load_kms+0x1a/0x120 [amdgpu] [ +0.000662] amdgpu_pci_p ---truncated---
In the Linux kernel, the following vulnerability has been resolved: ublk: detach gendisk from ublk device if add_disk() fails Inside ublk_abort_requests(), gendisk is grabbed for aborting all inflight requests. And ublk_abort_requests() is called when exiting the uring context or handling timeout. If add_disk() fails, the gendisk may have been freed when calling ublk_abort_requests(), so use-after-free can be caused when getting disk's reference in ublk_abort_requests(). Fixes the bug by detaching gendisk from ublk device if add_disk() fails.
In the Linux kernel, the following vulnerability has been resolved: spi: mpc52xx: fix use-after-free on registration failure Make sure to disable and free the interrupts in case controller registration fails to avoid a potential use-after-free and resource leak. This issue was flagged by Sashiko when reviewing a controller deregistration fix.
In the Linux kernel, the following vulnerability has been resolved: binder: fix node UAF in binder_add_freeze_work() In binder_add_freeze_work() we iterate over the proc->nodes with the proc->inner_lock held. However, this lock is temporarily dropped in order to acquire the node->lock first (lock nesting order). This can race with binder_node_release() and trigger a use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c Write of size 4 at addr ffff53c04c29dd04 by task freeze/640 CPU: 5 UID: 0 PID: 640 Comm: freeze Not tainted 6.11.0-07343-ga727812a8d45 #17 Hardware name: linux,dummy-virt (DT) Call trace: _raw_spin_lock+0xe4/0x19c binder_add_freeze_work+0x148/0x478 binder_ioctl+0x1e70/0x25ac __arm64_sys_ioctl+0x124/0x190 Allocated by task 637: __kmalloc_cache_noprof+0x12c/0x27c binder_new_node+0x50/0x700 binder_transaction+0x35ac/0x6f74 binder_thread_write+0xfb8/0x42a0 binder_ioctl+0x18f0/0x25ac __arm64_sys_ioctl+0x124/0x190 Freed by task 637: kfree+0xf0/0x330 binder_thread_read+0x1e88/0x3a68 binder_ioctl+0x16d8/0x25ac __arm64_sys_ioctl+0x124/0x190 ================================================================== Fix the race by taking a temporary reference on the node before releasing the proc->inner lock. This ensures the node remains alive while in use.
In the Linux kernel, the following vulnerability has been resolved: eventpoll: fix ep_remove struct eventpoll / struct file UAF ep_remove() (via ep_remove_file()) cleared file->f_ep under file->f_lock but then kept using @file inside the critical section (is_file_epoll(), hlist_del_rcu() through the head, spin_unlock). A concurrent __fput() taking the eventpoll_release() fastpath in that window observed the transient NULL, skipped eventpoll_release_file() and ran to f_op->release / file_free(). For the epoll-watches-epoll case, f_op->release is ep_eventpoll_release() -> ep_clear_and_put() -> ep_free(), which kfree()s the watched struct eventpoll. Its embedded ->refs hlist_head is exactly where epi->fllink.pprev points, so the subsequent hlist_del_rcu()'s "*pprev = next" scribbles into freed kmalloc-192 memory. In addition, struct file is SLAB_TYPESAFE_BY_RCU, so the slot backing @file could be recycled by alloc_empty_file() -- reinitializing f_lock and f_ep -- while ep_remove() is still nominally inside that lock. The upshot is an attacker-controllable kmem_cache_free() against the wrong slab cache. Pin @file via epi_fget() at the top of ep_remove() and gate the critical section on the pin succeeding. With the pin held @file cannot reach refcount zero, which holds __fput() off and transitively keeps the watched struct eventpoll alive across the hlist_del_rcu() and the f_lock use, closing both UAFs. If the pin fails @file has already reached refcount zero and its __fput() is in flight. Because we bailed before clearing f_ep, that path takes the eventpoll_release() slow path into eventpoll_release_file() and blocks on ep->mtx until the waiter side's ep_clear_and_put() drops it. The bailed epi's share of ep->refcount stays intact, so the trailing ep_refcount_dec_and_test() in ep_clear_and_put() cannot free the eventpoll out from under eventpoll_release_file(); the orphaned epi is then cleaned up there. A successful pin also proves we are not racing eventpoll_release_file() on this epi, so drop the now-redundant re-check of epi->dying under f_lock. The cheap lockless READ_ONCE(epi->dying) fast-path bailout stays.
In the Linux kernel, the following vulnerability has been resolved: net: defer final 'struct net' free in netns dismantle Ilya reported a slab-use-after-free in dst_destroy [1] Issue is in xfrm6_net_init() and xfrm4_net_init() : They copy xfrm[46]_dst_ops_template into net->xfrm.xfrm[46]_dst_ops. But net structure might be freed before all the dst callbacks are called. So when dst_destroy() calls later : if (dst->ops->destroy) dst->ops->destroy(dst); dst->ops points to the old net->xfrm.xfrm[46]_dst_ops, which has been freed. See a relevant issue fixed in : ac888d58869b ("net: do not delay dst_entries_add() in dst_release()") A fix is to queue the 'struct net' to be freed after one another cleanup_net() round (and existing rcu_barrier()) [1] BUG: KASAN: slab-use-after-free in dst_destroy (net/core/dst.c:112) Read of size 8 at addr ffff8882137ccab0 by task swapper/37/0 Dec 03 05:46:18 kernel: CPU: 37 UID: 0 PID: 0 Comm: swapper/37 Kdump: loaded Not tainted 6.12.0 #67 Hardware name: Red Hat KVM/RHEL, BIOS 1.16.1-1.el9 04/01/2014 Call Trace: <IRQ> dump_stack_lvl (lib/dump_stack.c:124) print_address_description.constprop.0 (mm/kasan/report.c:378) ? dst_destroy (net/core/dst.c:112) print_report (mm/kasan/report.c:489) ? dst_destroy (net/core/dst.c:112) ? kasan_addr_to_slab (mm/kasan/common.c:37) kasan_report (mm/kasan/report.c:603) ? dst_destroy (net/core/dst.c:112) ? rcu_do_batch (kernel/rcu/tree.c:2567) dst_destroy (net/core/dst.c:112) rcu_do_batch (kernel/rcu/tree.c:2567) ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2491) ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4339 kernel/locking/lockdep.c:4406) rcu_core (kernel/rcu/tree.c:2825) handle_softirqs (kernel/softirq.c:554) __irq_exit_rcu (kernel/softirq.c:589 kernel/softirq.c:428 kernel/softirq.c:637) irq_exit_rcu (kernel/softirq.c:651) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) </IRQ> <TASK> asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:92 arch/x86/kernel/process.c:743) Code: 00 4d 29 c8 4c 01 c7 4c 29 c2 e9 6e ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 0f 00 2d c7 c9 27 00 fb f4 <fa> c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 RSP: 0018:ffff888100d2fe00 EFLAGS: 00000246 RAX: 00000000001870ed RBX: 1ffff110201a5fc2 RCX: ffffffffb61a3e46 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffb3d4d123 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed11c7e1835d R10: ffff888e3f0c1aeb R11: 0000000000000000 R12: 0000000000000000 R13: ffff888100d20000 R14: dffffc0000000000 R15: 0000000000000000 ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:148) ? cpuidle_idle_call (kernel/sched/idle.c:186) default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) cpuidle_idle_call (kernel/sched/idle.c:186) ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) ? lock_release (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5848) ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) do_idle (kernel/sched/idle.c:326) cpu_startup_entry (kernel/sched/idle.c:423 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:202 arch/x86/kernel/smpboot.c:282) ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:232) ? soft_restart_cpu (arch/x86/kernel/head_64.S:452) common_startup_64 (arch/x86/kernel/head_64.S:414) </TASK> Dec 03 05:46:18 kernel: Allocated by task 12184: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (./arch/x86/include/asm/current.h:49 mm/kasan/common.c:60 mm/kasan/common.c:69) __kasan_slab_alloc (mm/kasan/common.c:319 mm/kasan/common.c:345) kmem_cache_alloc_noprof (mm/slub.c:4085 mm/slub.c:4134 mm/slub.c:4141) copy_net_ns (net/core/net_namespace.c:421 net/core/net_namespace.c:480) create_new_namespaces ---truncated---
In the Linux kernel, the following vulnerability has been resolved: xfrm: defensively unhash xfrm_state lists in __xfrm_state_delete KASAN reproduces a slab-use-after-free in __xfrm_state_delete()'s hlist_del_rcu calls under syzkaller load on linux-6.12.y stable (reproduced on 6.12.47, also reachable via the same code path on torvalds/master and on the ipsec tree). Nine unique signatures cluster in the xfrm_state lifecycle, the load-bearing one being: BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:990 [inline] BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:516 [inline] BUG: KASAN: slab-use-after-free in __xfrm_state_delete net/xfrm/xfrm_state.c Write of size 8 at addr ffff8881198bcb70 by task kworker/u8:9/435 Workqueue: netns cleanup_net Call Trace: __hlist_del / hlist_del_rcu __xfrm_state_delete xfrm_state_delete xfrm_state_flush xfrm_state_fini ops_exit_list cleanup_net The other observed signatures hit the same slab object from __xfrm_state_lookup, xfrm_alloc_spi, __xfrm_state_insert and an OOB write variant of __xfrm_state_delete, all on the byseq/byspi hash chains. __xfrm_state_delete() guards its byseq and byspi unhashes with value-based predicates: if (x->km.seq) hlist_del_rcu(&x->byseq); if (x->id.spi) hlist_del_rcu(&x->byspi); while everywhere else in the file (e.g. state_cache, state_cache_input) the safer hlist_unhashed() check is used. xfrm_alloc_spi() sets x->id.spi = newspi inside xfrm_state_lock and then immediately inserts into byspi, but a path that observes x->id.spi != 0 outside of xfrm_state_lock can still skip-or-hit the byspi unhash inconsistently with whether x is actually on the list. The same holds for x->km.seq versus byseq, and the bydst/bysrc unhashes have no predicate at all, so a second __xfrm_state_delete() on the same object writes through LIST_POISON pprev. The defensive change here: - Use hlist_del_init_rcu() instead of hlist_del_rcu() on bydst, bysrc, byseq and byspi so a second deletion is a no-op rather than a write through LIST_POISON pprev. The byseq/byspi nodes are already initialised in xfrm_state_alloc(). - Test hlist_unhashed() rather than the value predicate for byseq/byspi, so the unhash decision tracks list state rather than mutable scalar fields. Empirical verification: applied this patch on top of v6.12.47, rebuilt, and re-ran the same syzkaller harness for 1h16m on a previously-crashy configuration that produced ~100 hits each of slab-use-after-free Read in xfrm_alloc_spi / Read in __xfrm_state_lookup / Write in __xfrm_state_delete. After the patch, 7.1M execs across 32 VMs at ~1550 exec/sec produced zero xfrm_state UAF/OOB hits. /proc/slabinfo confirms the xfrm_state slab is actively allocated and freed during the run (~143 KiB resident), so the fuzzer is still exercising those code paths -- they just no longer crash. Reproduction: - Linux 6.12.47 x86_64 + KASAN_GENERIC + KASAN_INLINE + KCOV - syzkaller @ 746545b8b1e4c3a128db8652b340d3df90ce61db - 32 QEMU/KVM VMs x 2 vCPU on AWS c5.metal bare metal - 9 unique signatures collected in ~9h, all within xfrm_state lifecycle
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btmtk: avoid UAF in btmtk_process_coredump hci_devcd_append may lead to the release of the skb, so it cannot be accessed once it is called. ================================================================== BUG: KASAN: slab-use-after-free in btmtk_process_coredump+0x2a7/0x2d0 [btmtk] Read of size 4 at addr ffff888033cfabb0 by task kworker/0:3/82 CPU: 0 PID: 82 Comm: kworker/0:3 Tainted: G U 6.6.40-lockdep-03464-g1d8b4eb3060e #1 b0b3c1cc0c842735643fb411799d97921d1f688c Hardware name: Google Yaviks_Ufs/Yaviks_Ufs, BIOS Google_Yaviks_Ufs.15217.552.0 05/07/2024 Workqueue: events btusb_rx_work [btusb] Call Trace: <TASK> dump_stack_lvl+0xfd/0x150 print_report+0x131/0x780 kasan_report+0x177/0x1c0 btmtk_process_coredump+0x2a7/0x2d0 [btmtk 03edd567dd71a65958807c95a65db31d433e1d01] btusb_recv_acl_mtk+0x11c/0x1a0 [btusb 675430d1e87c4f24d0c1f80efe600757a0f32bec] btusb_rx_work+0x9e/0xe0 [btusb 675430d1e87c4f24d0c1f80efe600757a0f32bec] worker_thread+0xe44/0x2cc0 kthread+0x2ff/0x3a0 ret_from_fork+0x51/0x80 ret_from_fork_asm+0x1b/0x30 </TASK> Allocated by task 82: stack_trace_save+0xdc/0x190 kasan_set_track+0x4e/0x80 __kasan_slab_alloc+0x4e/0x60 kmem_cache_alloc+0x19f/0x360 skb_clone+0x132/0xf70 btusb_recv_acl_mtk+0x104/0x1a0 [btusb] btusb_rx_work+0x9e/0xe0 [btusb] worker_thread+0xe44/0x2cc0 kthread+0x2ff/0x3a0 ret_from_fork+0x51/0x80 ret_from_fork_asm+0x1b/0x30 Freed by task 1733: stack_trace_save+0xdc/0x190 kasan_set_track+0x4e/0x80 kasan_save_free_info+0x28/0xb0 ____kasan_slab_free+0xfd/0x170 kmem_cache_free+0x183/0x3f0 hci_devcd_rx+0x91a/0x2060 [bluetooth] worker_thread+0xe44/0x2cc0 kthread+0x2ff/0x3a0 ret_from_fork+0x51/0x80 ret_from_fork_asm+0x1b/0x30 The buggy address belongs to the object at ffff888033cfab40 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 112 bytes inside of freed 232-byte region [ffff888033cfab40, ffff888033cfac28) The buggy address belongs to the physical page: page:00000000a174ba93 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33cfa head:00000000a174ba93 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x4000000000000840(slab|head|zone=1) page_type: 0xffffffff() raw: 4000000000000840 ffff888100848a00 0000000000000000 0000000000000001 raw: 0000000000000000 0000000080190019 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888033cfaa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff888033cfab00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff888033cfab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888033cfac00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff888033cfac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Check if we need to call hci_devcd_complete before calling hci_devcd_append. That requires that we check data->cd_info.cnt >= MTK_COREDUMP_NUM instead of data->cd_info.cnt > MTK_COREDUMP_NUM, as we increment data->cd_info.cnt only once the call to hci_devcd_append succeeds.
In the Linux kernel, the following vulnerability has been resolved: net: qrtr: ns: Fix use-after-free in driver remove() In the remove callback, if a packet arrives after destroy_workqueue() is called, but before sock_release(), the qrtr_ns_data_ready() callback will try to queue the work, causing use-after-free issue. Fix this issue by saving the default 'sk_data_ready' callback during qrtr_ns_init() and use it to replace the qrtr_ns_data_ready() callback at the start of remove(). This ensures that even if a packet arrives after destroy_workqueue(), the work struct will not be dereferenced. Note that it is also required to ensure that the RX threads are completed before destroying the workqueue, because the threads could be using the qrtr_ns_data_ready() callback.
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: do not leave dangling sk pointer on error in l2cap_sock_create() bt_sock_alloc() allocates the sk object and attaches it to the provided sock object. On error l2cap_sock_alloc() frees the sk object, but the dangling pointer is still attached to the sock object, which may create use-after-free in other code.
In the Linux kernel, the following vulnerability has been resolved: tipc: Fix use-after-free of kernel socket in cleanup_bearer(). syzkaller reported a use-after-free of UDP kernel socket in cleanup_bearer() without repro. [0][1] When bearer_disable() calls tipc_udp_disable(), cleanup of the UDP kernel socket is deferred by work calling cleanup_bearer(). tipc_exit_net() waits for such works to finish by checking tipc_net(net)->wq_count. However, the work decrements the count too early before releasing the kernel socket, unblocking cleanup_net() and resulting in use-after-free. Let's move the decrement after releasing the socket in cleanup_bearer(). [0]: ref_tracker: net notrefcnt@000000009b3d1faf has 1/1 users at sk_alloc+0x438/0x608 inet_create+0x4c8/0xcb0 __sock_create+0x350/0x6b8 sock_create_kern+0x58/0x78 udp_sock_create4+0x68/0x398 udp_sock_create+0x88/0xc8 tipc_udp_enable+0x5e8/0x848 __tipc_nl_bearer_enable+0x84c/0xed8 tipc_nl_bearer_enable+0x38/0x60 genl_family_rcv_msg_doit+0x170/0x248 genl_rcv_msg+0x400/0x5b0 netlink_rcv_skb+0x1dc/0x398 genl_rcv+0x44/0x68 netlink_unicast+0x678/0x8b0 netlink_sendmsg+0x5e4/0x898 ____sys_sendmsg+0x500/0x830 [1]: BUG: KMSAN: use-after-free in udp_hashslot include/net/udp.h:85 [inline] BUG: KMSAN: use-after-free in udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 udp_hashslot include/net/udp.h:85 [inline] udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 sk_common_release+0xaf/0x3f0 net/core/sock.c:3820 inet_release+0x1e0/0x260 net/ipv4/af_inet.c:437 inet6_release+0x6f/0xd0 net/ipv6/af_inet6.c:489 __sock_release net/socket.c:658 [inline] sock_release+0xa0/0x210 net/socket.c:686 cleanup_bearer+0x42d/0x4c0 net/tipc/udp_media.c:819 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391 kthread+0x531/0x6b0 kernel/kthread.c:389 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 Uninit was created at: slab_free_hook mm/slub.c:2269 [inline] slab_free mm/slub.c:4580 [inline] kmem_cache_free+0x207/0xc40 mm/slub.c:4682 net_free net/core/net_namespace.c:454 [inline] cleanup_net+0x16f2/0x19d0 net/core/net_namespace.c:647 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391 kthread+0x531/0x6b0 kernel/kthread.c:389 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 CPU: 0 UID: 0 PID: 54 Comm: kworker/0:2 Not tainted 6.12.0-rc1-00131-gf66ebf37d69c #7 91723d6f74857f70725e1583cba3cf4adc716cfa Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Workqueue: events cleanup_bearer
In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Fix slab-use-after-free read in sg_release() Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN: BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407 In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp. After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error. Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures: - No references to sfp or sdp occur after the reference count is decremented. - Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release(). The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in sg_release().
In the Linux kernel, the following vulnerability has been resolved: crypto: atmel-sha204a - Fix potential UAF and memory leak in remove path Unregister the hwrng to prevent new ->read() calls and flush the Atmel I2C workqueue before teardown to prevent a potential UAF if a queued callback runs while the device is being removed. Drop the early return to ensure sysfs entries are removed and ->hwrng.priv is freed, preventing a memory leak.