In the Linux kernel, the following vulnerability has been resolved: tracing: Have format file honor EVENT_FILE_FL_FREED When eventfs was introduced, special care had to be done to coordinate the freeing of the file meta data with the files that are exposed to user space. The file meta data would have a ref count that is set when the file is created and would be decremented and freed after the last user that opened the file closed it. When the file meta data was to be freed, it would set a flag (EVENT_FILE_FL_FREED) to denote that the file is freed, and any new references made (like new opens or reads) would fail as it is marked freed. This allowed other meta data to be freed after this flag was set (under the event_mutex). All the files that were dynamically created in the events directory had a pointer to the file meta data and would call event_release() when the last reference to the user space file was closed. This would be the time that it is safe to free the file meta data. A shortcut was made for the "format" file. It's i_private would point to the "call" entry directly and not point to the file's meta data. This is because all format files are the same for the same "call", so it was thought there was no reason to differentiate them. The other files maintain state (like the "enable", "trigger", etc). But this meant if the file were to disappear, the "format" file would be unaware of it. This caused a race that could be trigger via the user_events test (that would create dynamic events and free them), and running a loop that would read the user_events format files: In one console run: # cd tools/testing/selftests/user_events # while true; do ./ftrace_test; done And in another console run: # cd /sys/kernel/tracing/ # while true; do cat events/user_events/__test_event/format; done 2>/dev/null With KASAN memory checking, it would trigger a use-after-free bug report (which was a real bug). This was because the format file was not checking the file's meta data flag "EVENT_FILE_FL_FREED", so it would access the event that the file meta data pointed to after the event was freed. After inspection, there are other locations that were found to not check the EVENT_FILE_FL_FREED flag when accessing the trace_event_file. Add a new helper function: event_file_file() that will make sure that the event_mutex is held, and will return NULL if the trace_event_file has the EVENT_FILE_FL_FREED flag set. Have the first reference of the struct file pointer use event_file_file() and check for NULL. Later uses can still use the event_file_data() helper function if the event_mutex is still held and was not released since the event_file_file() call.

In the Linux kernel, the following vulnerability has been resolved: scsi: aacraid: Fix double-free on probe failure aac_probe_one() calls hardware-specific init functions through the aac_driver_ident::init pointer, all of which eventually call down to aac_init_adapter(). If aac_init_adapter() fails after allocating memory for aac_dev::queues, it frees the memory but does not clear that member. After the hardware-specific init function returns an error, aac_probe_one() goes down an error path that frees the memory pointed to by aac_dev::queues, resulting.in a double-free.

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: st: fix probed platform device ref count on probe error path The probe function never performs any paltform device allocation, thus error path "undo_platform_dev_alloc" is entirely bogus. It drops the reference count from the platform device being probed. If error path is triggered, this will lead to unbalanced device reference counts and premature release of device resources, thus possible use-after-free when releasing remaining devm-managed resources.

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: core: Prevent USB core invalid event buffer address access This commit addresses an issue where the USB core could access an invalid event buffer address during runtime suspend, potentially causing SMMU faults and other memory issues in Exynos platforms. The problem arises from the following sequence. 1. In dwc3_gadget_suspend, there is a chance of a timeout when moving the USB core to the halt state after clearing the run/stop bit by software. 2. In dwc3_core_exit, the event buffer is cleared regardless of the USB core's status, which may lead to an SMMU faults and other memory issues. if the USB core tries to access the event buffer address. To prevent this hardware quirk on Exynos platforms, this commit ensures that the event buffer address is not cleared by software when the USB core is active during runtime suspend by checking its status before clearing the buffer address.

In the Linux kernel, the following vulnerability has been resolved: gtp: fix a potential NULL pointer dereference When sockfd_lookup() fails, gtp_encap_enable_socket() returns a NULL pointer, but its callers only check for error pointers thus miss the NULL pointer case. Fix it by returning an error pointer with the error code carried from sockfd_lookup(). (I found this bug during code inspection.)

In the Linux kernel, the following vulnerability has been resolved: pinctrl: single: fix potential NULL dereference in pcs_get_function() pinmux_generic_get_function() can return NULL and the pointer 'function' was dereferenced without checking against NULL. Add checking of pointer 'function' in pcs_get_function(). Found by code review.

In the Linux kernel, the following vulnerability has been resolved: smb/client: avoid dereferencing rdata=NULL in smb2_new_read_req() This happens when called from SMB2_read() while using rdma and reaching the rdma_readwrite_threshold.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix a use-after-free when hitting errors inside btrfs_submit_chunk() [BUG] There is an internal report that KASAN is reporting use-after-free, with the following backtrace: BUG: KASAN: slab-use-after-free in btrfs_check_read_bio+0xa68/0xb70 [btrfs] Read of size 4 at addr ffff8881117cec28 by task kworker/u16:2/45 CPU: 1 UID: 0 PID: 45 Comm: kworker/u16:2 Not tainted 6.11.0-rc2-next-20240805-default+ #76 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 Workqueue: btrfs-endio btrfs_end_bio_work [btrfs] Call Trace: dump_stack_lvl+0x61/0x80 print_address_description.constprop.0+0x5e/0x2f0 print_report+0x118/0x216 kasan_report+0x11d/0x1f0 btrfs_check_read_bio+0xa68/0xb70 [btrfs] process_one_work+0xce0/0x12a0 worker_thread+0x717/0x1250 kthread+0x2e3/0x3c0 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x11/0x20 Allocated by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 __kasan_slab_alloc+0x7d/0x80 kmem_cache_alloc_noprof+0x16e/0x3e0 mempool_alloc_noprof+0x12e/0x310 bio_alloc_bioset+0x3f0/0x7a0 btrfs_bio_alloc+0x2e/0x50 [btrfs] submit_extent_page+0x4d1/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x50 __kasan_slab_free+0x4b/0x60 kmem_cache_free+0x214/0x5d0 bio_free+0xed/0x180 end_bbio_data_read+0x1cc/0x580 [btrfs] btrfs_submit_chunk+0x98d/0x1880 [btrfs] btrfs_submit_bio+0x33/0x70 [btrfs] submit_one_bio+0xd4/0x130 [btrfs] submit_extent_page+0x3ea/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [CAUSE] Although I cannot reproduce the error, the report itself is good enough to pin down the cause. The call trace is the regular endio workqueue context, but the free-by-task trace is showing that during btrfs_submit_chunk() we already hit a critical error, and is calling btrfs_bio_end_io() to error out. And the original endio function called bio_put() to free the whole bio. This means a double freeing thus causing use-after-free, e.g.: 1. Enter btrfs_submit_bio() with a read bio The read bio length is 128K, crossing two 64K stripes. 2. The first run of btrfs_submit_chunk() 2.1 Call btrfs_map_block(), which returns 64K 2.2 Call btrfs_split_bio() Now there are two bios, one referring to the first 64K, the other referring to the second 64K. 2.3 The first half is submitted. 3. The second run of btrfs_submit_chunk() 3.1 Call btrfs_map_block(), which by somehow failed Now we call btrfs_bio_end_io() to handle the error 3.2 btrfs_bio_end_io() calls the original endio function Which is end_bbio_data_read(), and it calls bio_put() for the original bio. Now the original bio is freed. 4. The submitted first 64K bio finished Now we call into btrfs_check_read_bio() and tries to advance the bio iter. But since the original bio (thus its iter) is already freed, we trigger the above use-after free. And even if the memory is not poisoned/corrupted, we will later call the original endio function, causing a double freeing. [FIX] Instead of calling btrfs_bio_end_io(), call btrfs_orig_bbio_end_io(), which has the extra check on split bios and do the pr ---truncated---

In the Linux kernel, the following vulnerability has been resolved: soc: qcom: cmd-db: Map shared memory as WC, not WB Linux does not write into cmd-db region. This region of memory is write protected by XPU. XPU may sometime falsely detect clean cache eviction as "write" into the write protected region leading to secure interrupt which causes an endless loop somewhere in Trust Zone. The only reason it is working right now is because Qualcomm Hypervisor maps the same region as Non-Cacheable memory in Stage 2 translation tables. The issue manifests if we want to use another hypervisor (like Xen or KVM), which does not know anything about those specific mappings. Changing the mapping of cmd-db memory from MEMREMAP_WB to MEMREMAP_WT/WC removes dependency on correct mappings in Stage 2 tables. This patch fixes the issue by updating the mapping to MEMREMAP_WC. I tested this on SA8155P with Xen.

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: scm: Mark get_wq_ctx() as atomic call Currently get_wq_ctx() is wrongly configured as a standard call. When two SMC calls are in sleep and one SMC wakes up, it calls get_wq_ctx() to resume the corresponding sleeping thread. But if get_wq_ctx() is interrupted, goes to sleep and another SMC call is waiting to be allocated a waitq context, it leads to a deadlock. To avoid this get_wq_ctx() must be an atomic call and can't be a standard SMC call. Hence mark get_wq_ctx() as a fast call.

In the Linux kernel, the following vulnerability has been resolved: soc: qcom: pmic_glink: Fix race during initialization As pointed out by Stephen Boyd it is possible that during initialization of the pmic_glink child drivers, the protection-domain notifiers fires, and the associated work is scheduled, before the client registration returns and as a result the local "client" pointer has been initialized. The outcome of this is a NULL pointer dereference as the "client" pointer is blindly dereferenced. Timeline provided by Stephen: CPU0 CPU1 ---- ---- ucsi->client = NULL; devm_pmic_glink_register_client() client->pdr_notify(client->priv, pg->client_state) pmic_glink_ucsi_pdr_notify() schedule_work(&ucsi->register_work) pmic_glink_ucsi_register() ucsi_register() pmic_glink_ucsi_read_version() pmic_glink_ucsi_read() pmic_glink_ucsi_read() pmic_glink_send(ucsi->client) ucsi->client = client // Too late! This code is identical across the altmode, battery manager and usci child drivers. Resolve this by splitting the allocation of the "client" object and the registration thereof into two operations. This only happens if the protection domain registry is populated at the time of registration, which by the introduction of commit '1ebcde047c54 ("soc: qcom: add pd-mapper implementation")' became much more likely.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: avoid using null object of framebuffer Instead of using state->fb->obj[0] directly, get object from framebuffer by calling drm_gem_fb_get_obj() and return error code when object is null to avoid using null object of framebuffer. (cherry picked from commit 73dd0ad9e5dad53766ea3e631303430116f834b3)

In the Linux kernel, the following vulnerability has been resolved: selinux,smack: don't bypass permissions check in inode_setsecctx hook Marek Gresko reports that the root user on an NFS client is able to change the security labels on files on an NFS filesystem that is exported with root squashing enabled. The end of the kerneldoc comment for __vfs_setxattr_noperm() states: * This function requires the caller to lock the inode's i_mutex before it * is executed. It also assumes that the caller will make the appropriate * permission checks. nfsd_setattr() does do permissions checking via fh_verify() and nfsd_permission(), but those don't do all the same permissions checks that are done by security_inode_setxattr() and its related LSM hooks do. Since nfsd_setattr() is the only consumer of security_inode_setsecctx(), simplest solution appears to be to replace the call to __vfs_setxattr_noperm() with a call to __vfs_setxattr_locked(). This fixes the above issue and has the added benefit of causing nfsd to recall conflicting delegations on a file when a client tries to change its security label.

In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: Fix prime with external buffers Make sure that for external buffers mapping goes through the dma_buf interface instead of trying to access pages directly. External buffers might not provide direct access to readable/writable pages so to make sure the bo's created from external dma_bufs can be read dma_buf interface has to be used. Fixes crashes in IGT's kms_prime with vgem. Regular desktop usage won't trigger this due to the fact that virtual machines will not have multiple GPUs but it enables better test coverage in IGT.

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: fix ID 0 endp usage after multiple re-creations 'local_addr_used' and 'add_addr_accepted' are decremented for addresses not related to the initial subflow (ID0), because the source and destination addresses of the initial subflows are known from the beginning: they don't count as "additional local address being used" or "ADD_ADDR being accepted". It is then required not to increment them when the entrypoint used by the initial subflow is removed and re-added during a connection. Without this modification, this entrypoint cannot be removed and re-added more than once.

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: Fix null pointer dereference in trace ucsi_register_altmode checks IS_ERR for the alt pointer and treats NULL as valid. When CONFIG_TYPEC_DP_ALTMODE is not enabled, ucsi_register_displayport returns NULL which causes a NULL pointer dereference in trace. Rather than return NULL, call typec_port_register_altmode to register DisplayPort alternate mode as a non-controllable mode when CONFIG_TYPEC_DP_ALTMODE is not enabled.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix dereference after null check check the pointer hive before use.

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix possible NULL pointer dereference profile->parent->dents[AAFS_PROF_DIR] could be NULL only if its parent is made from __create_missing_ancestors(..) and 'ent->old' is NULL in aa_replace_profiles(..). In that case, it must return an error code and the code, -ENOENT represents its state that the path of its parent is not existed yet. BUG: kernel NULL pointer dereference, address: 0000000000000030 PGD 0 P4D 0 PREEMPT SMP PTI CPU: 4 PID: 3362 Comm: apparmor_parser Not tainted 6.8.0-24-generic #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0 Call Trace: ? show_regs+0x6d/0x80 ? __die+0x24/0x80 ? page_fault_oops+0x99/0x1b0 ? kernelmode_fixup_or_oops+0xb2/0x140 ? __bad_area_nosemaphore+0x1a5/0x2c0 ? find_vma+0x34/0x60 ? bad_area_nosemaphore+0x16/0x30 ? do_user_addr_fault+0x2a2/0x6b0 ? exc_page_fault+0x83/0x1b0 ? asm_exc_page_fault+0x27/0x30 ? aafs_create.constprop.0+0x7f/0x130 ? aafs_create.constprop.0+0x51/0x130 __aafs_profile_mkdir+0x3d6/0x480 aa_replace_profiles+0x83f/0x1270 policy_update+0xe3/0x180 profile_load+0xbc/0x150 ? rw_verify_area+0x47/0x140 vfs_write+0x100/0x480 ? __x64_sys_openat+0x55/0xa0 ? syscall_exit_to_user_mode+0x86/0x260 ksys_write+0x73/0x100 __x64_sys_write+0x19/0x30 x64_sys_call+0x7e/0x25c0 do_syscall_64+0x7f/0x180 entry_SYSCALL_64_after_hwframe+0x78/0x80 RIP: 0033:0x7be9f211c574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007ffd26f2b8c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00005d504415e200 RCX: 00007be9f211c574 RDX: 0000000000001fc1 RSI: 00005d504418bc80 RDI: 0000000000000004 RBP: 0000000000001fc1 R08: 0000000000001fc1 R09: 0000000080000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00005d504418bc80 R13: 0000000000000004 R14: 00007ffd26f2b9b0 R15: 00007ffd26f2ba30 Modules linked in: snd_seq_dummy snd_hrtimer qrtr snd_hda_codec_generic snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device i2c_i801 snd_timer i2c_smbus qxl snd soundcore drm_ttm_helper lpc_ich ttm joydev input_leds serio_raw mac_hid binfmt_misc msr parport_pc ppdev lp parport efi_pstore nfnetlink dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid ahci libahci psmouse virtio_rng xhci_pci xhci_pci_renesas CR2: 0000000000000030 ---[ end trace 0000000000000000 ]--- RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix mc_data out-of-bounds read warning Clear warning that read mc_data[i-1] may out-of-bounds.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix ucode out-of-bounds read warning Clear warning that read ucode[] may out-of-bounds.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix out-of-bounds read of df_v1_7_channel_number Check the fb_channel_number range to avoid the array out-of-bounds read error

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix out-of-bounds write warning Check the ring type value to fix the out-of-bounds write warning

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Ensure index calculation will not overflow [WHY & HOW] Make sure vmid0p72_idx, vnom0p8_idx and vmax0p9_idx calculation will never overflow and exceess array size. This fixes 3 OVERRUN and 1 INTEGER_OVERFLOW issues reported by Coverity.

In the Linux kernel, the following vulnerability has been resolved: ublk_drv: fix NULL pointer dereference in ublk_ctrl_start_recovery() When two UBLK_CMD_START_USER_RECOVERY commands are submitted, the first one sets 'ubq->ubq_daemon' to NULL, and the second one triggers WARN in ublk_queue_reinit() and subsequently a NULL pointer dereference issue. Fix it by adding the check in ublk_ctrl_start_recovery() and return immediately in case of zero 'ub->nr_queues_ready'. BUG: kernel NULL pointer dereference, address: 0000000000000028 RIP: 0010:ublk_ctrl_start_recovery.constprop.0+0x82/0x180 Call Trace: ? __die+0x20/0x70 ? page_fault_oops+0x75/0x170 ? exc_page_fault+0x64/0x140 ? asm_exc_page_fault+0x22/0x30 ? ublk_ctrl_start_recovery.constprop.0+0x82/0x180 ublk_ctrl_uring_cmd+0x4f7/0x6c0 ? pick_next_task_idle+0x26/0x40 io_uring_cmd+0x9a/0x1b0 io_issue_sqe+0x193/0x3f0 io_wq_submit_work+0x9b/0x390 io_worker_handle_work+0x165/0x360 io_wq_worker+0xcb/0x2f0 ? finish_task_switch.isra.0+0x203/0x290 ? finish_task_switch.isra.0+0x203/0x290 ? __pfx_io_wq_worker+0x10/0x10 ret_from_fork+0x2d/0x50 ? __pfx_io_wq_worker+0x10/0x10 ret_from_fork_asm+0x1a/0x30

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix kernel crash if commands allocation fails If the commands allocation fails in nvmet_tcp_alloc_cmds() the kernel crashes in nvmet_tcp_release_queue_work() because of a NULL pointer dereference. nvmet: failed to install queue 0 cntlid 1 ret 6 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 Fix the bug by setting queue->nr_cmds to zero in case nvmet_tcp_alloc_cmd() fails.

In the Linux kernel, the following vulnerability has been resolved: VMCI: Fix use-after-free when removing resource in vmci_resource_remove() When removing a resource from vmci_resource_table in vmci_resource_remove(), the search is performed using the resource handle by comparing context and resource fields. It is possible though to create two resources with different types but same handle (same context and resource fields). When trying to remove one of the resources, vmci_resource_remove() may not remove the intended one, but the object will still be freed as in the case of the datagram type in vmci_datagram_destroy_handle(). vmci_resource_table will still hold a pointer to this freed resource leading to a use-after-free vulnerability. BUG: KASAN: use-after-free in vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline] BUG: KASAN: use-after-free in vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147 Read of size 4 at addr ffff88801c16d800 by task syz-executor197/1592 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x82/0xa9 lib/dump_stack.c:106 print_address_description.constprop.0+0x21/0x366 mm/kasan/report.c:239 __kasan_report.cold+0x7f/0x132 mm/kasan/report.c:425 kasan_report+0x38/0x51 mm/kasan/report.c:442 vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline] vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147 vmci_qp_broker_detach+0x89a/0x11b9 drivers/misc/vmw_vmci/vmci_queue_pair.c:2182 ctx_free_ctx+0x473/0xbe1 drivers/misc/vmw_vmci/vmci_context.c:444 kref_put include/linux/kref.h:65 [inline] vmci_ctx_put drivers/misc/vmw_vmci/vmci_context.c:497 [inline] vmci_ctx_destroy+0x170/0x1d6 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x125/0x1ac drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x261/0xa34 fs/file_table.c:282 task_work_run+0xf0/0x194 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x184/0x189 kernel/entry/common.c:187 exit_to_user_mode_prepare+0x11b/0x123 kernel/entry/common.c:220 __syscall_exit_to_user_mode_work kernel/entry/common.c:302 [inline] syscall_exit_to_user_mode+0x18/0x42 kernel/entry/common.c:313 do_syscall_64+0x41/0x85 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x6e/0x0 This change ensures the type is also checked when removing the resource from vmci_resource_table in vmci_resource_remove().

In the Linux kernel, the following vulnerability has been resolved: uio_hv_generic: Fix kernel NULL pointer dereference in hv_uio_rescind For primary VM Bus channels, primary_channel pointer is always NULL. This pointer is valid only for the secondary channels. Also, rescind callback is meant for primary channels only. Fix NULL pointer dereference by retrieving the device_obj from the parent for the primary channel.

In the Linux kernel, the following vulnerability has been resolved: binder: fix UAF caused by offsets overwrite Binder objects are processed and copied individually into the target buffer during transactions. Any raw data in-between these objects is copied as well. However, this raw data copy lacks an out-of-bounds check. If the raw data exceeds the data section size then the copy overwrites the offsets section. This eventually triggers an error that attempts to unwind the processed objects. However, at this point the offsets used to index these objects are now corrupted. Unwinding with corrupted offsets can result in decrements of arbitrary nodes and lead to their premature release. Other users of such nodes are left with a dangling pointer triggering a use-after-free. This issue is made evident by the following KASAN report (trimmed): ================================================================== BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c Write of size 4 at addr ffff47fc91598f04 by task binder-util/743 CPU: 9 UID: 0 PID: 743 Comm: binder-util Not tainted 6.11.0-rc4 #1 Hardware name: linux,dummy-virt (DT) Call trace: _raw_spin_lock+0xe4/0x19c binder_free_buf+0x128/0x434 binder_thread_write+0x8a4/0x3260 binder_ioctl+0x18f0/0x258c [...] Allocated by task 743: __kmalloc_cache_noprof+0x110/0x270 binder_new_node+0x50/0x700 binder_transaction+0x413c/0x6da8 binder_thread_write+0x978/0x3260 binder_ioctl+0x18f0/0x258c [...] Freed by task 745: kfree+0xbc/0x208 binder_thread_read+0x1c5c/0x37d4 binder_ioctl+0x16d8/0x258c [...] ================================================================== To avoid this issue, let's check that the raw data copy is within the boundaries of the data section.

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix double free of 'buf' in error path smatch warning: drivers/misc/fastrpc.c:1926 fastrpc_req_mmap() error: double free of 'buf' In fastrpc_req_mmap() error path, the fastrpc buffer is freed in fastrpc_req_munmap_impl() if unmap is successful. But in the end, there is an unconditional call to fastrpc_buf_free(). So the above case triggers the double free of fastrpc buf.

In the Linux kernel, the following vulnerability has been resolved: smb/server: fix potential null-ptr-deref of lease_ctx_info in smb2_open() null-ptr-deref will occur when (req_op_level == SMB2_OPLOCK_LEVEL_LEASE) and parse_lease_state() return NULL. Fix this by check if 'lease_ctx_info' is NULL. Additionally, remove the redundant parentheses in parse_durable_handle_context().

In the Linux kernel, the following vulnerability has been resolved: of/irq: Prevent device address out-of-bounds read in interrupt map walk When of_irq_parse_raw() is invoked with a device address smaller than the interrupt parent node (from #address-cells property), KASAN detects the following out-of-bounds read when populating the initial match table (dyndbg="func of_irq_parse_* +p"): OF: of_irq_parse_one: dev=/soc@0/picasso/watchdog, index=0 OF: parent=/soc@0/pci@878000000000/gpio0@17,0, intsize=2 OF: intspec=4 OF: of_irq_parse_raw: ipar=/soc@0/pci@878000000000/gpio0@17,0, size=2 OF: -> addrsize=3 ================================================================== BUG: KASAN: slab-out-of-bounds in of_irq_parse_raw+0x2b8/0x8d0 Read of size 4 at addr ffffff81beca5608 by task bash/764 CPU: 1 PID: 764 Comm: bash Tainted: G O 6.1.67-484c613561-nokia_sm_arm64 #1 Hardware name: Unknown Unknown Product/Unknown Product, BIOS 2023.01-12.24.03-dirty 01/01/2023 Call trace: dump_backtrace+0xdc/0x130 show_stack+0x1c/0x30 dump_stack_lvl+0x6c/0x84 print_report+0x150/0x448 kasan_report+0x98/0x140 __asan_load4+0x78/0xa0 of_irq_parse_raw+0x2b8/0x8d0 of_irq_parse_one+0x24c/0x270 parse_interrupts+0xc0/0x120 of_fwnode_add_links+0x100/0x2d0 fw_devlink_parse_fwtree+0x64/0xc0 device_add+0xb38/0xc30 of_device_add+0x64/0x90 of_platform_device_create_pdata+0xd0/0x170 of_platform_bus_create+0x244/0x600 of_platform_notify+0x1b0/0x254 blocking_notifier_call_chain+0x9c/0xd0 __of_changeset_entry_notify+0x1b8/0x230 __of_changeset_apply_notify+0x54/0xe4 of_overlay_fdt_apply+0xc04/0xd94 ... The buggy address belongs to the object at ffffff81beca5600 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 8 bytes inside of 128-byte region [ffffff81beca5600, ffffff81beca5680) The buggy address belongs to the physical page: page:00000000230d3d03 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1beca4 head:00000000230d3d03 order:1 compound_mapcount:0 compound_pincount:0 flags: 0x8000000000010200(slab|head|zone=2) raw: 8000000000010200 0000000000000000 dead000000000122 ffffff810000c300 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffffff81beca5500: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffffff81beca5580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffffff81beca5600: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffffff81beca5680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffffff81beca5700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ================================================================== OF: -> got it ! Prevent the out-of-bounds read by copying the device address into a buffer of sufficient size.

In the Linux kernel, the following vulnerability has been resolved: HID: cougar: fix slab-out-of-bounds Read in cougar_report_fixup report_fixup for the Cougar 500k Gaming Keyboard was not verifying that the report descriptor size was correct before accessing it

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btnxpuart: Fix Null pointer dereference in btnxpuart_flush() This adds a check before freeing the rx->skb in flush and close functions to handle the kernel crash seen while removing driver after FW download fails or before FW download completes. dmesg log: [ 54.634586] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000080 [ 54.643398] Mem abort info: [ 54.646204] ESR = 0x0000000096000004 [ 54.649964] EC = 0x25: DABT (current EL), IL = 32 bits [ 54.655286] SET = 0, FnV = 0 [ 54.658348] EA = 0, S1PTW = 0 [ 54.661498] FSC = 0x04: level 0 translation fault [ 54.666391] Data abort info: [ 54.669273] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 54.674768] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 54.674771] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 54.674775] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000048860000 [ 54.674780] [0000000000000080] pgd=0000000000000000, p4d=0000000000000000 [ 54.703880] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 54.710152] Modules linked in: btnxpuart(-) overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce polyval_generic snd_soc_imx_spdif snd_soc_imx_card snd_soc_ak5558 snd_soc_ak4458 caam secvio error snd_soc_fsl_micfil snd_soc_fsl_spdif snd_soc_fsl_sai snd_soc_fsl_utils imx_pcm_dma gpio_ir_recv rc_core sch_fq_codel fuse [ 54.744357] CPU: 3 PID: 72 Comm: kworker/u9:0 Not tainted 6.6.3-otbr-g128004619037 #2 [ 54.744364] Hardware name: FSL i.MX8MM EVK board (DT) [ 54.744368] Workqueue: hci0 hci_power_on [ 54.757244] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 54.757249] pc : kfree_skb_reason+0x18/0xb0 [ 54.772299] lr : btnxpuart_flush+0x40/0x58 [btnxpuart] [ 54.782921] sp : ffff8000805ebca0 [ 54.782923] x29: ffff8000805ebca0 x28: ffffa5c6cf1869c0 x27: ffffa5c6cf186000 [ 54.782931] x26: ffff377b84852400 x25: ffff377b848523c0 x24: ffff377b845e7230 [ 54.782938] x23: ffffa5c6ce8dbe08 x22: ffffa5c6ceb65410 x21: 00000000ffffff92 [ 54.782945] x20: ffffa5c6ce8dbe98 x19: ffffffffffffffac x18: ffffffffffffffff [ 54.807651] x17: 0000000000000000 x16: ffffa5c6ce2824ec x15: ffff8001005eb857 [ 54.821917] x14: 0000000000000000 x13: ffffa5c6cf1a02e0 x12: 0000000000000642 [ 54.821924] x11: 0000000000000040 x10: ffffa5c6cf19d690 x9 : ffffa5c6cf19d688 [ 54.821931] x8 : ffff377b86000028 x7 : 0000000000000000 x6 : 0000000000000000 [ 54.821938] x5 : ffff377b86000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 54.843331] x2 : 0000000000000000 x1 : 0000000000000002 x0 : ffffffffffffffac [ 54.857599] Call trace: [ 54.857601] kfree_skb_reason+0x18/0xb0 [ 54.863878] btnxpuart_flush+0x40/0x58 [btnxpuart] [ 54.863888] hci_dev_open_sync+0x3a8/0xa04 [ 54.872773] hci_power_on+0x54/0x2e4 [ 54.881832] process_one_work+0x138/0x260 [ 54.881842] worker_thread+0x32c/0x438 [ 54.881847] kthread+0x118/0x11c [ 54.881853] ret_from_fork+0x10/0x20 [ 54.896406] Code: a9be7bfd 910003fd f9000bf3 aa0003f3 (b940d400) [ 54.896410] ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: can: mcp251x: fix deadlock if an interrupt occurs during mcp251x_open The mcp251x_hw_wake() function is called with the mpc_lock mutex held and disables the interrupt handler so that no interrupts can be processed while waking the device. If an interrupt has already occurred then waiting for the interrupt handler to complete will deadlock because it will be trying to acquire the same mutex. CPU0 CPU1 ---- ---- mcp251x_open() mutex_lock(&priv->mcp_lock) request_threaded_irq() mcp251x_can_ist() mutex_lock(&priv->mcp_lock) mcp251x_hw_wake() disable_irq() <-- deadlock Use disable_irq_nosync() instead because the interrupt handler does everything while holding the mutex so it doesn't matter if it's still running.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: unset the binding mark of a reused connection Steve French reported null pointer dereference error from sha256 lib. cifs.ko can send session setup requests on reused connection. If reused connection is used for binding session, conn->binding can still remain true and generate_preauth_hash() will not set sess->Preauth_HashValue and it will be NULL. It is used as a material to create an encryption key in ksmbd_gen_smb311_encryptionkey. ->Preauth_HashValue cause null pointer dereference error from crypto_shash_update(). BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 8 PID: 429254 Comm: kworker/8:39 Hardware name: LENOVO 20MAS08500/20MAS08500, BIOS N2CET69W (1.52 ) Workqueue: ksmbd-io handle_ksmbd_work [ksmbd] RIP: 0010:lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3] ? show_regs+0x6d/0x80 ? __die+0x24/0x80 ? page_fault_oops+0x99/0x1b0 ? do_user_addr_fault+0x2ee/0x6b0 ? exc_page_fault+0x83/0x1b0 ? asm_exc_page_fault+0x27/0x30 ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] ? lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3] ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] _sha256_update+0x77/0xa0 [sha256_ssse3] sha256_avx2_update+0x15/0x30 [sha256_ssse3] crypto_shash_update+0x1e/0x40 hmac_update+0x12/0x20 crypto_shash_update+0x1e/0x40 generate_key+0x234/0x380 [ksmbd] generate_smb3encryptionkey+0x40/0x1c0 [ksmbd] ksmbd_gen_smb311_encryptionkey+0x72/0xa0 [ksmbd] ntlm_authenticate.isra.0+0x423/0x5d0 [ksmbd] smb2_sess_setup+0x952/0xaa0 [ksmbd] __process_request+0xa3/0x1d0 [ksmbd] __handle_ksmbd_work+0x1c4/0x2f0 [ksmbd] handle_ksmbd_work+0x2d/0xa0 [ksmbd] process_one_work+0x16c/0x350 worker_thread+0x306/0x440 ? __pfx_worker_thread+0x10/0x10 kthread+0xef/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x44/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double put of @cfile in smb2_set_path_size() If smb2_compound_op() is called with a valid @cfile and returned -EINVAL, we need to call cifs_get_writable_path() before retrying it as the reference of @cfile was already dropped by previous call. This fixes the following KASAN splat when running fstests generic/013 against Windows Server 2022: CIFS: Attempting to mount //w22-fs0/scratch run fstests generic/013 at 2024-09-02 19:48:59 ================================================================== BUG: KASAN: slab-use-after-free in detach_if_pending+0xab/0x200 Write of size 8 at addr ffff88811f1a3730 by task kworker/3:2/176 CPU: 3 UID: 0 PID: 176 Comm: kworker/3:2 Not tainted 6.11.0-rc6 #2 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014 Workqueue: cifsoplockd cifs_oplock_break [cifs] Call Trace: dump_stack_lvl+0x5d/0x80 ? detach_if_pending+0xab/0x200 print_report+0x156/0x4d9 ? detach_if_pending+0xab/0x200 ? __virt_addr_valid+0x145/0x300 ? __phys_addr+0x46/0x90 ? detach_if_pending+0xab/0x200 kasan_report+0xda/0x110 ? detach_if_pending+0xab/0x200 detach_if_pending+0xab/0x200 timer_delete+0x96/0xe0 ? __pfx_timer_delete+0x10/0x10 ? rcu_is_watching+0x20/0x50 try_to_grab_pending+0x46/0x3b0 __cancel_work+0x89/0x1b0 ? __pfx___cancel_work+0x10/0x10 ? kasan_save_track+0x14/0x30 cifs_close_deferred_file+0x110/0x2c0 [cifs] ? __pfx_cifs_close_deferred_file+0x10/0x10 [cifs] ? __pfx_down_read+0x10/0x10 cifs_oplock_break+0x4c1/0xa50 [cifs] ? __pfx_cifs_oplock_break+0x10/0x10 [cifs] ? lock_is_held_type+0x85/0xf0 ? mark_held_locks+0x1a/0x90 process_one_work+0x4c6/0x9f0 ? find_held_lock+0x8a/0xa0 ? __pfx_process_one_work+0x10/0x10 ? lock_acquired+0x220/0x550 ? __list_add_valid_or_report+0x37/0x100 worker_thread+0x2e4/0x570 ? __kthread_parkme+0xd1/0xf0 ? __pfx_worker_thread+0x10/0x10 kthread+0x17f/0x1c0 ? kthread+0xda/0x1c0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Allocated by task 1118: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0xaa/0xb0 cifs_new_fileinfo+0xc8/0x9d0 [cifs] cifs_atomic_open+0x467/0x770 [cifs] lookup_open.isra.0+0x665/0x8b0 path_openat+0x4c3/0x1380 do_filp_open+0x167/0x270 do_sys_openat2+0x129/0x160 __x64_sys_creat+0xad/0xe0 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 83: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x70 poison_slab_object+0xe9/0x160 __kasan_slab_free+0x32/0x50 kfree+0xf2/0x300 process_one_work+0x4c6/0x9f0 worker_thread+0x2e4/0x570 kthread+0x17f/0x1c0 ret_from_fork+0x31/0x60 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x30/0x50 __kasan_record_aux_stack+0xad/0xc0 insert_work+0x29/0xe0 __queue_work+0x5ea/0x760 queue_work_on+0x6d/0x90 _cifsFileInfo_put+0x3f6/0x770 [cifs] smb2_compound_op+0x911/0x3940 [cifs] smb2_set_path_size+0x228/0x270 [cifs] cifs_set_file_size+0x197/0x460 [cifs] cifs_setattr+0xd9c/0x14b0 [cifs] notify_change+0x4e3/0x740 do_truncate+0xfa/0x180 vfs_truncate+0x195/0x200 __x64_sys_truncate+0x109/0x150 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: powerpc/qspinlock: Fix deadlock in MCS queue If an interrupt occurs in queued_spin_lock_slowpath() after we increment qnodesp->count and before node->lock is initialized, another CPU might see stale lock values in get_tail_qnode(). If the stale lock value happens to match the lock on that CPU, then we write to the "next" pointer of the wrong qnode. This causes a deadlock as the former CPU, once it becomes the head of the MCS queue, will spin indefinitely until it's "next" pointer is set by its successor in the queue. Running stress-ng on a 16 core (16EC/16VP) shared LPAR, results in occasional lockups similar to the following: $ stress-ng --all 128 --vm-bytes 80% --aggressive \ --maximize --oomable --verify --syslog \ --metrics --times --timeout 5m watchdog: CPU 15 Hard LOCKUP ...... NIP [c0000000000b78f4] queued_spin_lock_slowpath+0x1184/0x1490 LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90 Call Trace: 0xc000002cfffa3bf0 (unreliable) _raw_spin_lock+0x6c/0x90 raw_spin_rq_lock_nested.part.135+0x4c/0xd0 sched_ttwu_pending+0x60/0x1f0 __flush_smp_call_function_queue+0x1dc/0x670 smp_ipi_demux_relaxed+0xa4/0x100 xive_muxed_ipi_action+0x20/0x40 __handle_irq_event_percpu+0x80/0x240 handle_irq_event_percpu+0x2c/0x80 handle_percpu_irq+0x84/0xd0 generic_handle_irq+0x54/0x80 __do_irq+0xac/0x210 __do_IRQ+0x74/0xd0 0x0 do_IRQ+0x8c/0x170 hardware_interrupt_common_virt+0x29c/0x2a0 --- interrupt: 500 at queued_spin_lock_slowpath+0x4b8/0x1490 ...... NIP [c0000000000b6c28] queued_spin_lock_slowpath+0x4b8/0x1490 LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90 --- interrupt: 500 0xc0000029c1a41d00 (unreliable) _raw_spin_lock+0x6c/0x90 futex_wake+0x100/0x260 do_futex+0x21c/0x2a0 sys_futex+0x98/0x270 system_call_exception+0x14c/0x2f0 system_call_vectored_common+0x15c/0x2ec The following code flow illustrates how the deadlock occurs. For the sake of brevity, assume that both locks (A and B) are contended and we call the queued_spin_lock_slowpath() function. CPU0 CPU1 ---- ---- spin_lock_irqsave(A) | spin_unlock_irqrestore(A) | spin_lock(B) | | | ? | id = qnodesp->count++; | (Note that nodes[0].lock == A) | | | ? | Interrupt | (happens before "nodes[0].lock = B") | | | ? | spin_lock_irqsave(A) | | | ? | id = qnodesp->count++ | nodes[1].lock = A | | | ? | Tail of MCS queue | | spin_lock_irqsave(A) ? | Head of MCS queue ? | CPU0 is previous tail ? | Spin indefinitely ? (until "nodes[1].next != NULL") prev = get_tail_qnode(A, CPU0) | ? prev == &qnodes[CPU0].nodes[0] (as qnodes ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ASoC: dapm: Fix UAF for snd_soc_pcm_runtime object When using kernel with the following extra config, - CONFIG_KASAN=y - CONFIG_KASAN_GENERIC=y - CONFIG_KASAN_INLINE=y - CONFIG_KASAN_VMALLOC=y - CONFIG_FRAME_WARN=4096 kernel detects that snd_pcm_suspend_all() access a freed 'snd_soc_pcm_runtime' object when the system is suspended, which leads to a use-after-free bug: [ 52.047746] BUG: KASAN: use-after-free in snd_pcm_suspend_all+0x1a8/0x270 [ 52.047765] Read of size 1 at addr ffff0000b9434d50 by task systemd-sleep/2330 [ 52.047785] Call trace: [ 52.047787] dump_backtrace+0x0/0x3c0 [ 52.047794] show_stack+0x34/0x50 [ 52.047797] dump_stack_lvl+0x68/0x8c [ 52.047802] print_address_description.constprop.0+0x74/0x2c0 [ 52.047809] kasan_report+0x210/0x230 [ 52.047815] __asan_report_load1_noabort+0x3c/0x50 [ 52.047820] snd_pcm_suspend_all+0x1a8/0x270 [ 52.047824] snd_soc_suspend+0x19c/0x4e0 The snd_pcm_sync_stop() has a NULL check on 'substream->runtime' before making any access. So we need to always set 'substream->runtime' to NULL everytime we kfree() it.

In the Linux kernel, the following vulnerability has been resolved: sch/netem: fix use after free in netem_dequeue If netem_dequeue() enqueues packet to inner qdisc and that qdisc returns __NET_XMIT_STOLEN. The packet is dropped but qdisc_tree_reduce_backlog() is not called to update the parent's q.qlen, leading to the similar use-after-free as Commit e04991a48dbaf382 ("netem: fix return value if duplicate enqueue fails") Commands to trigger KASAN UaF: ip link add type dummy ip link set lo up ip link set dummy0 up tc qdisc add dev lo parent root handle 1: drr tc filter add dev lo parent 1: basic classid 1:1 tc class add dev lo classid 1:1 drr tc qdisc add dev lo parent 1:1 handle 2: netem tc qdisc add dev lo parent 2: handle 3: drr tc filter add dev lo parent 3: basic classid 3:1 action mirred egress redirect dev dummy0 tc class add dev lo classid 3:1 drr ping -c1 -W0.01 localhost # Trigger bug tc class del dev lo classid 1:1 tc class add dev lo classid 1:1 drr ping -c1 -W0.01 localhost # UaF