Search Results (20134 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2022-50881 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: Fix use-after-free in ath9k_hif_usb_disconnect() This patch fixes a use-after-free in ath9k that occurs in ath9k_hif_usb_disconnect() when ath9k_destroy_wmi() is trying to access 'drv_priv' that has already been freed by ieee80211_free_hw(), called by ath9k_htc_hw_deinit(). The patch moves ath9k_destroy_wmi() before ieee80211_free_hw(). Note that urbs from the driver should be killed before freeing 'wmi' with ath9k_destroy_wmi() as their callbacks will access 'wmi'. Found by a modified version of syzkaller. ================================================================== BUG: KASAN: use-after-free in ath9k_destroy_wmi+0x38/0x40 Read of size 8 at addr ffff8881069132a0 by task kworker/0:1/7 CPU: 0 PID: 7 Comm: kworker/0:1 Tainted: G O 5.14.0+ #131 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x8e/0xd1 print_address_description.constprop.0.cold+0x93/0x334 ? ath9k_destroy_wmi+0x38/0x40 ? ath9k_destroy_wmi+0x38/0x40 kasan_report.cold+0x83/0xdf ? ath9k_destroy_wmi+0x38/0x40 ath9k_destroy_wmi+0x38/0x40 ath9k_hif_usb_disconnect+0x329/0x3f0 ? ath9k_hif_usb_suspend+0x120/0x120 ? usb_disable_interface+0xfc/0x180 usb_unbind_interface+0x19b/0x7e0 ? usb_autoresume_device+0x50/0x50 device_release_driver_internal+0x44d/0x520 bus_remove_device+0x2e5/0x5a0 device_del+0x5b2/0xe30 ? __device_link_del+0x370/0x370 ? usb_remove_ep_devs+0x43/0x80 ? remove_intf_ep_devs+0x112/0x1a0 usb_disable_device+0x1e3/0x5a0 usb_disconnect+0x267/0x870 hub_event+0x168d/0x3950 ? rcu_read_lock_sched_held+0xa1/0xd0 ? hub_port_debounce+0x2e0/0x2e0 ? check_irq_usage+0x860/0xf20 ? drain_workqueue+0x281/0x360 ? lock_release+0x640/0x640 ? rcu_read_lock_sched_held+0xa1/0xd0 ? rcu_read_lock_bh_held+0xb0/0xb0 ? lockdep_hardirqs_on_prepare+0x273/0x3e0 process_one_work+0x92b/0x1460 ? pwq_dec_nr_in_flight+0x330/0x330 ? rwlock_bug.part.0+0x90/0x90 worker_thread+0x95/0xe00 ? __kthread_parkme+0x115/0x1e0 ? process_one_work+0x1460/0x1460 kthread+0x3a1/0x480 ? set_kthread_struct+0x120/0x120 ret_from_fork+0x1f/0x30 The buggy address belongs to the page: page:ffffea00041a44c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106913 flags: 0x200000000000000(node=0|zone=2) raw: 0200000000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 3, migratetype Unmovable, gfp_mask 0x40dc0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), pid 7, ts 38347963444, free_ts 41399957635 prep_new_page+0x1aa/0x240 get_page_from_freelist+0x159a/0x27c0 __alloc_pages+0x2da/0x6a0 alloc_pages+0xec/0x1e0 kmalloc_order+0x39/0xf0 kmalloc_order_trace+0x19/0x120 __kmalloc+0x308/0x390 wiphy_new_nm+0x6f5/0x1dd0 ieee80211_alloc_hw_nm+0x36d/0x2230 ath9k_htc_probe_device+0x9d/0x1e10 ath9k_htc_hw_init+0x34/0x50 ath9k_hif_usb_firmware_cb+0x25f/0x4e0 request_firmware_work_func+0x131/0x240 process_one_work+0x92b/0x1460 worker_thread+0x95/0xe00 kthread+0x3a1/0x480 page last free stack trace: free_pcp_prepare+0x3d3/0x7f0 free_unref_page+0x1e/0x3d0 device_release+0xa4/0x240 kobject_put+0x186/0x4c0 put_device+0x20/0x30 ath9k_htc_disconnect_device+0x1cf/0x2c0 ath9k_htc_hw_deinit+0x26/0x30 ath9k_hif_usb_disconnect+0x2d9/0x3f0 usb_unbind_interface+0x19b/0x7e0 device_release_driver_internal+0x44d/0x520 bus_remove_device+0x2e5/0x5a0 device_del+0x5b2/0xe30 usb_disable_device+0x1e3/0x5a0 usb_disconnect+0x267/0x870 hub_event+0x168d/0x3950 process_one_work+0x92b/0x1460 Memory state around the buggy address: ffff888106913180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888106913200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888 ---truncated---
CVE-2022-50882 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Fix memory leak in uvc_gpio_parse Previously the unit buffer was allocated before checking the IRQ for privacy GPIO. In case of error, the unit buffer was leaked. Allocate the unit buffer after the IRQ to avoid it. Addresses-Coverity-ID: 1474639 ("Resource leak")
CVE-2022-50889 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: dm integrity: Fix UAF in dm_integrity_dtr() Dm_integrity also has the same UAF problem when dm_resume() and dm_destroy() are concurrent. Therefore, cancelling timer again in dm_integrity_dtr().
CVE-2022-50883 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: bpf: Prevent decl_tag from being referenced in func_proto arg Syzkaller managed to hit another decl_tag issue: btf_func_proto_check kernel/bpf/btf.c:4506 [inline] btf_check_all_types kernel/bpf/btf.c:4734 [inline] btf_parse_type_sec+0x1175/0x1980 kernel/bpf/btf.c:4763 btf_parse kernel/bpf/btf.c:5042 [inline] btf_new_fd+0x65a/0xb00 kernel/bpf/btf.c:6709 bpf_btf_load+0x6f/0x90 kernel/bpf/syscall.c:4342 __sys_bpf+0x50a/0x6c0 kernel/bpf/syscall.c:5034 __do_sys_bpf kernel/bpf/syscall.c:5093 [inline] __se_sys_bpf kernel/bpf/syscall.c:5091 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5091 do_syscall_64+0x54/0x70 arch/x86/entry/common.c:48 This seems similar to commit ea68376c8bed ("bpf: prevent decl_tag from being referenced in func_proto") but for the argument.
CVE-2022-50884 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm: Prevent drm_copy_field() to attempt copying a NULL pointer There are some struct drm_driver fields that are required by drivers since drm_copy_field() attempts to copy them to user-space via DRM_IOCTL_VERSION. But it can be possible that a driver has a bug and did not set some of the fields, which leads to drm_copy_field() attempting to copy a NULL pointer: [ +10.395966] Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000 [ +0.010955] Mem abort info: [ +0.002835] ESR = 0x0000000096000004 [ +0.003872] EC = 0x25: DABT (current EL), IL = 32 bits [ +0.005395] SET = 0, FnV = 0 [ +0.003113] EA = 0, S1PTW = 0 [ +0.003182] FSC = 0x04: level 0 translation fault [ +0.004964] Data abort info: [ +0.002919] ISV = 0, ISS = 0x00000004 [ +0.003886] CM = 0, WnR = 0 [ +0.003040] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000115dad000 [ +0.006536] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ +0.006925] Internal error: Oops: 96000004 [#1] SMP ... [ +0.011113] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ +0.007061] pc : __pi_strlen+0x14/0x150 [ +0.003895] lr : drm_copy_field+0x30/0x1a4 [ +0.004156] sp : ffff8000094b3a50 [ +0.003355] x29: ffff8000094b3a50 x28: ffff8000094b3b70 x27: 0000000000000040 [ +0.007242] x26: ffff443743c2ba00 x25: 0000000000000000 x24: 0000000000000040 [ +0.007243] x23: ffff443743c2ba00 x22: ffff8000094b3b70 x21: 0000000000000000 [ +0.007241] x20: 0000000000000000 x19: ffff8000094b3b90 x18: 0000000000000000 [ +0.007241] x17: 0000000000000000 x16: 0000000000000000 x15: 0000aaab14b9af40 [ +0.007241] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ +0.007239] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa524ad67d4d8 [ +0.007242] x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : 6c6e6263606e7141 [ +0.007239] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ +0.007241] x2 : 0000000000000000 x1 : ffff8000094b3b90 x0 : 0000000000000000 [ +0.007240] Call trace: [ +0.002475] __pi_strlen+0x14/0x150 [ +0.003537] drm_version+0x84/0xac [ +0.003448] drm_ioctl_kernel+0xa8/0x16c [ +0.003975] drm_ioctl+0x270/0x580 [ +0.003448] __arm64_sys_ioctl+0xb8/0xfc [ +0.003978] invoke_syscall+0x78/0x100 [ +0.003799] el0_svc_common.constprop.0+0x4c/0xf4 [ +0.004767] do_el0_svc+0x38/0x4c [ +0.003357] el0_svc+0x34/0x100 [ +0.003185] el0t_64_sync_handler+0x11c/0x150 [ +0.004418] el0t_64_sync+0x190/0x194 [ +0.003716] Code: 92402c04 b200c3e8 f13fc09f 5400088c (a9400c02) [ +0.006180] ---[ end trace 0000000000000000 ]---
CVE-2022-50885 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix NULL-ptr-deref in rxe_qp_do_cleanup() when socket create failed There is a null-ptr-deref when mount.cifs over rdma: BUG: KASAN: null-ptr-deref in rxe_qp_do_cleanup+0x2f3/0x360 [rdma_rxe] Read of size 8 at addr 0000000000000018 by task mount.cifs/3046 CPU: 2 PID: 3046 Comm: mount.cifs Not tainted 6.1.0-rc5+ #62 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc3 Call Trace: <TASK> dump_stack_lvl+0x34/0x44 kasan_report+0xad/0x130 rxe_qp_do_cleanup+0x2f3/0x360 [rdma_rxe] execute_in_process_context+0x25/0x90 __rxe_cleanup+0x101/0x1d0 [rdma_rxe] rxe_create_qp+0x16a/0x180 [rdma_rxe] create_qp.part.0+0x27d/0x340 ib_create_qp_kernel+0x73/0x160 rdma_create_qp+0x100/0x230 _smbd_get_connection+0x752/0x20f0 smbd_get_connection+0x21/0x40 cifs_get_tcp_session+0x8ef/0xda0 mount_get_conns+0x60/0x750 cifs_mount+0x103/0xd00 cifs_smb3_do_mount+0x1dd/0xcb0 smb3_get_tree+0x1d5/0x300 vfs_get_tree+0x41/0xf0 path_mount+0x9b3/0xdd0 __x64_sys_mount+0x190/0x1d0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 The root cause of the issue is the socket create failed in rxe_qp_init_req(). So move the reset rxe_qp_do_cleanup() after the NULL ptr check.
CVE-2022-50886 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mmc: toshsd: fix return value check of mmc_add_host() mmc_add_host() may return error, if we ignore its return value, the memory that allocated in mmc_alloc_host() will be leaked and it will lead a kernel crash because of deleting not added device in the remove path. So fix this by checking the return value and goto error path which will call mmc_free_host(), besides, free_irq() also needs be called.
CVE-2022-50887 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: regulator: core: fix unbalanced of node refcount in regulator_dev_lookup() I got the the following report: OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /i2c/pmic@62/regulators/exten In of_get_regulator(), the node is returned from of_parse_phandle() with refcount incremented, after using it, of_node_put() need be called.
CVE-2022-50888 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: remoteproc: qcom: q6v5: Fix potential null-ptr-deref in q6v5_wcss_init_mmio() q6v5_wcss_init_mmio() will call platform_get_resource_byname() that may fail and return NULL. devm_ioremap() will use res->start as input, which may causes null-ptr-deref. Check the ret value of platform_get_resource_byname() to avoid the null-ptr-deref.
CVE-2023-53830 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: platform/x86: think-lmi: Fix memory leak when showing current settings When retriving a item string with tlmi_setting(), the result has to be freed using kfree(). In current_value_show() however, malformed item strings are not freed, causing a memory leak. Fix this by eliminating the early return responsible for this.
CVE-2023-53819 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: amdgpu: validate offset_in_bo of drm_amdgpu_gem_va This is motivated by OOB access in amdgpu_vm_update_range when offset_in_bo+map_size overflows. v2: keep the validations in amdgpu_vm_bo_map v3: add the validations to amdgpu_vm_bo_map/amdgpu_vm_bo_replace_map rather than to amdgpu_gem_va_ioctl
CVE-2023-53818 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: ARM: zynq: Fix refcount leak in zynq_early_slcr_init of_find_compatible_node() returns a node pointer with refcount incremented, we should use of_node_put() on error path. Add missing of_node_put() to avoid refcount leak.
CVE-2023-53817 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: crypto: lib/mpi - avoid null pointer deref in mpi_cmp_ui() During NVMeTCP Authentication a controller can trigger a kernel oops by specifying the 8192 bit Diffie Hellman group and passing a correctly sized, but zeroed Diffie Hellamn value. mpi_cmp_ui() was detecting this if the second parameter was 0, but 1 is passed from dh_is_pubkey_valid(). This causes the null pointer u->d to be dereferenced towards the end of mpi_cmp_ui()
CVE-2023-53816 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: fix potential kgd_mem UAFs kgd_mem pointers returned by kfd_process_device_translate_handle are only guaranteed to be valid while p->mutex is held. As soon as the mutex is unlocked, another thread can free the BO.
CVE-2023-53839 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: dccp: fix data-race around dp->dccps_mss_cache dccp_sendmsg() reads dp->dccps_mss_cache before locking the socket. Same thing in do_dccp_getsockopt(). Add READ_ONCE()/WRITE_ONCE() annotations, and change dccp_sendmsg() to check again dccps_mss_cache after socket is locked.
CVE-2023-53809 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: l2tp: Avoid possible recursive deadlock in l2tp_tunnel_register() When a file descriptor of pppol2tp socket is passed as file descriptor of UDP socket, a recursive deadlock occurs in l2tp_tunnel_register(). This situation is reproduced by the following program: int main(void) { int sock; struct sockaddr_pppol2tp addr; sock = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP); if (sock < 0) { perror("socket"); return 1; } addr.sa_family = AF_PPPOX; addr.sa_protocol = PX_PROTO_OL2TP; addr.pppol2tp.pid = 0; addr.pppol2tp.fd = sock; addr.pppol2tp.addr.sin_family = PF_INET; addr.pppol2tp.addr.sin_port = htons(0); addr.pppol2tp.addr.sin_addr.s_addr = inet_addr("192.168.0.1"); addr.pppol2tp.s_tunnel = 1; addr.pppol2tp.s_session = 0; addr.pppol2tp.d_tunnel = 0; addr.pppol2tp.d_session = 0; if (connect(sock, (const struct sockaddr *)&addr, sizeof(addr)) < 0) { perror("connect"); return 1; } return 0; } This program causes the following lockdep warning: ============================================ WARNING: possible recursive locking detected 6.2.0-rc5-00205-gc96618275234 #56 Not tainted -------------------------------------------- repro/8607 is trying to acquire lock: ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: l2tp_tunnel_register+0x2b7/0x11c0 but task is already holding lock: ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0xa82/0x1a30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_PPPOX); lock(sk_lock-AF_PPPOX); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by repro/8607: #0: ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0xa82/0x1a30 stack backtrace: CPU: 0 PID: 8607 Comm: repro Not tainted 6.2.0-rc5-00205-gc96618275234 #56 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x100/0x178 __lock_acquire.cold+0x119/0x3b9 ? lockdep_hardirqs_on_prepare+0x410/0x410 lock_acquire+0x1e0/0x610 ? l2tp_tunnel_register+0x2b7/0x11c0 ? lock_downgrade+0x710/0x710 ? __fget_files+0x283/0x3e0 lock_sock_nested+0x3a/0xf0 ? l2tp_tunnel_register+0x2b7/0x11c0 l2tp_tunnel_register+0x2b7/0x11c0 ? sprintf+0xc4/0x100 ? l2tp_tunnel_del_work+0x6b0/0x6b0 ? debug_object_deactivate+0x320/0x320 ? lockdep_init_map_type+0x16d/0x7a0 ? lockdep_init_map_type+0x16d/0x7a0 ? l2tp_tunnel_create+0x2bf/0x4b0 ? l2tp_tunnel_create+0x3c6/0x4b0 pppol2tp_connect+0x14e1/0x1a30 ? pppol2tp_put_sk+0xd0/0xd0 ? aa_sk_perm+0x2b7/0xa80 ? aa_af_perm+0x260/0x260 ? bpf_lsm_socket_connect+0x9/0x10 ? pppol2tp_put_sk+0xd0/0xd0 __sys_connect_file+0x14f/0x190 __sys_connect+0x133/0x160 ? __sys_connect_file+0x190/0x190 ? lockdep_hardirqs_on+0x7d/0x100 ? ktime_get_coarse_real_ts64+0x1b7/0x200 ? ktime_get_coarse_real_ts64+0x147/0x200 ? __audit_syscall_entry+0x396/0x500 __x64_sys_connect+0x72/0xb0 do_syscall_64+0x38/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd This patch fixes the issue by getting/creating the tunnel before locking the pppol2tp socket.
CVE-2023-53808 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: fix memory leak in mwifiex_histogram_read() Always free the zeroed page on return from 'mwifiex_histogram_read()'.
CVE-2023-53807 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: clk: clocking-wizard: Fix Oops in clk_wzrd_register_divider() Smatch detected this potential error pointer dereference clk_wzrd_register_divider(). If devm_clk_hw_register() fails then it sets "hw" to an error pointer and then dereferences it on the next line. Return the error directly instead.
CVE-2023-53797 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: HID: wacom: Use ktime_t rather than int when dealing with timestamps Code which interacts with timestamps needs to use the ktime_t type returned by functions like ktime_get. The int type does not offer enough space to store these values, and attempting to use it is a recipe for problems. In this particular case, overflows would occur when calculating/storing timestamps leading to incorrect values being reported to userspace. In some cases these bad timestamps cause input handling in userspace to appear hung.
CVE-2023-53795 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: iommufd: IOMMUFD_DESTROY should not increase the refcount syzkaller found a race where IOMMUFD_DESTROY increments the refcount: obj = iommufd_get_object(ucmd->ictx, cmd->id, IOMMUFD_OBJ_ANY); if (IS_ERR(obj)) return PTR_ERR(obj); iommufd_ref_to_users(obj); /* See iommufd_ref_to_users() */ if (!iommufd_object_destroy_user(ucmd->ictx, obj)) As part of the sequence to join the two existing primitives together. Allowing the refcount the be elevated without holding the destroy_rwsem violates the assumption that all temporary refcount elevations are protected by destroy_rwsem. Racing IOMMUFD_DESTROY with iommufd_object_destroy_user() will cause spurious failures: WARNING: CPU: 0 PID: 3076 at drivers/iommu/iommufd/device.c:477 iommufd_access_destroy+0x18/0x20 drivers/iommu/iommufd/device.c:478 Modules linked in: CPU: 0 PID: 3076 Comm: syz-executor.0 Not tainted 6.3.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:iommufd_access_destroy+0x18/0x20 drivers/iommu/iommufd/device.c:477 Code: e8 3d 4e 00 00 84 c0 74 01 c3 0f 0b c3 0f 1f 44 00 00 f3 0f 1e fa 48 89 fe 48 8b bf a8 00 00 00 e8 1d 4e 00 00 84 c0 74 01 c3 <0f> 0b c3 0f 1f 44 00 00 41 57 41 56 41 55 4c 8d ae d0 00 00 00 41 RSP: 0018:ffffc90003067e08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888109ea0300 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000ffffffff RBP: 0000000000000004 R08: 0000000000000000 R09: ffff88810bbb3500 R10: ffff88810bbb3e48 R11: 0000000000000000 R12: ffffc90003067e88 R13: ffffc90003067ea8 R14: ffff888101249800 R15: 00000000fffffffe FS: 00007ff7254fe6c0(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557262da8 CR3: 000000010a6fd000 CR4: 0000000000350ef0 Call Trace: <TASK> iommufd_test_create_access drivers/iommu/iommufd/selftest.c:596 [inline] iommufd_test+0x71c/0xcf0 drivers/iommu/iommufd/selftest.c:813 iommufd_fops_ioctl+0x10f/0x1b0 drivers/iommu/iommufd/main.c:337 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+0x84/0xc0 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The solution is to not increment the refcount on the IOMMUFD_DESTROY path at all. Instead use the xa_lock to serialize everything. The refcount check == 1 and xa_erase can be done under a single critical region. This avoids the need for any refcount incrementing. It has the downside that if userspace races destroy with other operations it will get an EBUSY instead of waiting, but this is kind of racing is already dangerous.