Search Results (20044 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2025-40299 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: gve: Implement gettimex64 with -EOPNOTSUPP gve implemented a ptp_clock for sole use of do_aux_work at this time. ptp_clock_gettime() and ptp_sys_offset() assume every ptp_clock has implemented either gettimex64 or gettime64. Stub gettimex64 and return -EOPNOTSUPP to prevent NULL dereferencing.
CVE-2025-40301 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_event: validate skb length for unknown CC opcode In hci_cmd_complete_evt(), if the command complete event has an unknown opcode, we assume the first byte of the remaining skb->data contains the return status. However, parameter data has previously been pulled in hci_event_func(), which may leave the skb empty. If so, using skb->data[0] for the return status uses un-init memory. The fix is to check skb->len before using skb->data.
CVE-2025-40283 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: reorder cleanup in btusb_disconnect to avoid UAF There is a KASAN: slab-use-after-free read in btusb_disconnect(). Calling "usb_driver_release_interface(&btusb_driver, data->intf)" will free the btusb data associated with the interface. The same data is then used later in the function, hence the UAF. Fix by moving the accesses to btusb data to before the data is free'd.
CVE-2025-40282 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: 6lowpan: reset link-local header on ipv6 recv path Bluetooth 6lowpan.c netdev has header_ops, so it must set link-local header for RX skb, otherwise things crash, eg. with AF_PACKET SOCK_RAW Add missing skb_reset_mac_header() for uncompressed ipv6 RX path. For the compressed one, it is done in lowpan_header_decompress(). Log: (BlueZ 6lowpan-tester Client Recv Raw - Success) ------ kernel BUG at net/core/skbuff.c:212! Call Trace: <IRQ> ... packet_rcv (net/packet/af_packet.c:2152) ... <TASK> __local_bh_enable_ip (kernel/softirq.c:407) netif_rx (net/core/dev.c:5648) chan_recv_cb (net/bluetooth/6lowpan.c:294 net/bluetooth/6lowpan.c:359) ------
CVE-2025-40279 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: net: sched: act_connmark: initialize struct tc_ife to fix kernel leak In tcf_connmark_dump(), the variable 'opt' was partially initialized using a designatied initializer. While the padding bytes are reamined uninitialized. nla_put() copies the entire structure into a netlink message, these uninitialized bytes leaked to userspace. Initialize the structure with memset before assigning its fields to ensure all members and padding are cleared prior to beign copied.
CVE-2025-40276 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/panthor: Flush shmem writes before mapping buffers CPU-uncached The shmem layer zeroes out the new pages using cached mappings, and if we don't CPU-flush we might leave dirty cachelines behind, leading to potential data leaks and/or asynchronous buffer corruption when dirty cachelines are evicted.
CVE-2025-40307 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: exfat: validate cluster allocation bits of the allocation bitmap syzbot created an exfat image with cluster bits not set for the allocation bitmap. exfat-fs reads and uses the allocation bitmap without checking this. The problem is that if the start cluster of the allocation bitmap is 6, cluster 6 can be allocated when creating a directory with mkdir. exfat zeros out this cluster in exfat_mkdir, which can delete existing entries. This can reallocate the allocated entries. In addition, the allocation bitmap is also zeroed out, so cluster 6 can be reallocated. This patch adds exfat_test_bitmap_range to validate that clusters used for the allocation bitmap are correctly marked as in-use.
CVE-2025-40017 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: media: iris: Fix memory leak by freeing untracked persist buffer One internal buffer which is allocated only once per session was not being freed during session close because it was not being tracked as part of internal buffer list which resulted in a memory leak. Add the necessary logic to explicitly free the untracked internal buffer during session close to ensure all allocated memory is released properly.
CVE-2025-68804 1 Linux 1 Linux Kernel 2026-04-15 N/A
In the Linux kernel, the following vulnerability has been resolved: platform/chrome: cros_ec_ishtp: Fix UAF after unbinding driver After unbinding the driver, another kthread `cros_ec_console_log_work` is still accessing the device, resulting an UAF and crash. The driver doesn't unregister the EC device in .remove() which should shutdown sub-devices synchronously. Fix it.
CVE-2025-40312 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: jfs: Verify inode mode when loading from disk The inode mode loaded from corrupted disk can be invalid. Do like what commit 0a9e74051313 ("isofs: Verify inode mode when loading from disk") does.
CVE-2025-68167 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: gpiolib: fix invalid pointer access in debugfs If the memory allocation in gpiolib_seq_start() fails, the s->private field remains uninitialized and is later dereferenced without checking in gpiolib_seq_stop(). Initialize s->private to NULL before calling kzalloc() and check it before dereferencing it.
CVE-2025-68168 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: jfs: fix uninitialized waitqueue in transaction manager The transaction manager initialization in txInit() was not properly initializing TxBlock[0].waitor waitqueue, causing a crash when txEnd(0) is called on read-only filesystems. When a filesystem is mounted read-only, txBegin() returns tid=0 to indicate no transaction. However, txEnd(0) still gets called and tries to access TxBlock[0].waitor via tid_to_tblock(0), but this waitqueue was never initialized because the initialization loop started at index 1 instead of 0. This causes a 'non-static key' lockdep warning and system crash: INFO: trying to register non-static key in txEnd Fix by ensuring all transaction blocks including TxBlock[0] have their waitqueues properly initialized during txInit().
CVE-2025-68169 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: netpoll: Fix deadlock in memory allocation under spinlock Fix a AA deadlock in refill_skbs() where memory allocation while holding skb_pool->lock can trigger a recursive lock acquisition attempt. The deadlock scenario occurs when the system is under severe memory pressure: 1. refill_skbs() acquires skb_pool->lock (spinlock) 2. alloc_skb() is called while holding the lock 3. Memory allocator fails and calls slab_out_of_memory() 4. This triggers printk() for the OOM warning 5. The console output path calls netpoll_send_udp() 6. netpoll_send_udp() attempts to acquire the same skb_pool->lock 7. Deadlock: the lock is already held by the same CPU Call stack: refill_skbs() spin_lock_irqsave(&skb_pool->lock) <- lock acquired __alloc_skb() kmem_cache_alloc_node_noprof() slab_out_of_memory() printk() console_flush_all() netpoll_send_udp() skb_dequeue() spin_lock_irqsave(&skb_pool->lock) <- deadlock attempt This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb refilling on critical path") which removed refill_skbs() from the critical path (where nested printk was being deferred), letting nested printk being called from inside refill_skbs() Refactor refill_skbs() to never allocate memory while holding the spinlock. Another possible solution to fix this problem is protecting the refill_skbs() from nested printks, basically calling printk_deferred_{enter,exit}() in refill_skbs(), then, any nested pr_warn() would be deferred. I prefer this approach, given I _think_ it might be a good idea to move the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having the alloc_skb() outside of the lock will be necessary step. There is a possible TOCTOU issue when checking for the pool length, and queueing the new allocated skb, but, this is not an issue, given that an extra SKB in the pool is harmless and it will be eventually used.
CVE-2025-68170 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/radeon: Do not kfree() devres managed rdev Since the allocation of the drivers main structure was changed to devm_drm_dev_alloc() rdev is managed by devres and we shouldn't be calling kfree() on it. This fixes things exploding if the driver probe fails and devres cleans up the rdev after we already free'd it. (cherry picked from commit 16c0681617b8a045773d4d87b6140002fa75b03b)
CVE-2025-40072 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: fanotify: Validate the return value of mnt_ns_from_dentry() before dereferencing The function do_fanotify_mark() does not validate if mnt_ns_from_dentry() returns NULL before dereferencing mntns->user_ns. This causes a NULL pointer dereference in do_fanotify_mark() if the path is not a mount namespace object. Fix this by checking mnt_ns_from_dentry()'s return value before dereferencing it. Before the patch $ gcc fanotify_nullptr.c -o fanotify_nullptr $ mkdir A $ ./fanotify_nullptr Fanotify fd: 3 fanotify_mark: Operation not permitted $ unshare -Urm Fanotify fd: 3 Killed int main(void){ int ffd; ffd = fanotify_init(FAN_CLASS_NOTIF | FAN_REPORT_MNT, 0); if(ffd < 0){ perror("fanotify_init"); exit(EXIT_FAILURE); } printf("Fanotify fd: %d\n",ffd); if(fanotify_mark(ffd, FAN_MARK_ADD | FAN_MARK_MNTNS, FAN_MNT_ATTACH, AT_FDCWD, "A") < 0){ perror("fanotify_mark"); exit(EXIT_FAILURE); } return 0; } After the patch $ gcc fanotify_nullptr.c -o fanotify_nullptr $ mkdir A $ ./fanotify_nullptr Fanotify fd: 3 fanotify_mark: Operation not permitted $ unshare -Urm Fanotify fd: 3 fanotify_mark: Invalid argument [ 25.694973] BUG: kernel NULL pointer dereference, address: 0000000000000038 [ 25.695006] #PF: supervisor read access in kernel mode [ 25.695012] #PF: error_code(0x0000) - not-present page [ 25.695017] PGD 109a30067 P4D 109a30067 PUD 142b46067 PMD 0 [ 25.695025] Oops: Oops: 0000 [#1] SMP NOPTI [ 25.695032] CPU: 4 UID: 1000 PID: 1478 Comm: fanotify_nullpt Not tainted 6.17.0-rc4 #1 PREEMPT(lazy) [ 25.695040] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 [ 25.695049] RIP: 0010:do_fanotify_mark+0x817/0x950 [ 25.695066] Code: 04 00 00 e9 45 fd ff ff 48 8b 7c 24 48 4c 89 54 24 18 4c 89 5c 24 10 4c 89 0c 24 e8 b3 11 fc ff 4c 8b 54 24 18 4c 8b 5c 24 10 <48> 8b 78 38 4c 8b 0c 24 49 89 c4 e9 13 fd ff ff 8b 4c 24 28 85 c9 [ 25.695081] RSP: 0018:ffffd31c469e3c08 EFLAGS: 00010203 [ 25.695104] RAX: 0000000000000000 RBX: 0000000001000000 RCX: ffff8eb48aebd220 [ 25.695110] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8eb4835e8180 [ 25.695115] RBP: 0000000000000111 R08: 0000000000000000 R09: 0000000000000000 [ 25.695142] R10: ffff8eb48a7d56c0 R11: ffff8eb482bede00 R12: 00000000004012a7 [ 25.695148] R13: 0000000000000110 R14: 0000000000000001 R15: ffff8eb48a7d56c0 [ 25.695154] FS: 00007f8733bda740(0000) GS:ffff8eb61ce5f000(0000) knlGS:0000000000000000 [ 25.695162] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 25.695170] CR2: 0000000000000038 CR3: 0000000136994006 CR4: 00000000003706f0 [ 25.695201] Call Trace: [ 25.695209] <TASK> [ 25.695215] __x64_sys_fanotify_mark+0x1f/0x30 [ 25.695222] do_syscall_64+0x82/0x2c0 ...
CVE-2023-7324 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: scsi: ses: Fix possible addl_desc_ptr out-of-bounds accesses Sanitize possible addl_desc_ptr out-of-bounds accesses in ses_enclosure_data_process().
CVE-2025-68818 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: scsi: Revert "scsi: qla2xxx: Perform lockless command completion in abort path" This reverts commit 0367076b0817d5c75dfb83001ce7ce5c64d803a9. The commit being reverted added code to __qla2x00_abort_all_cmds() to call sp->done() without holding a spinlock. But unlike the older code below it, this new code failed to check sp->cmd_type and just assumed TYPE_SRB, which results in a jump to an invalid pointer in target-mode with TYPE_TGT_CMD: qla2xxx [0000:65:00.0]-d034:8: qla24xx_do_nack_work create sess success 0000000009f7a79b qla2xxx [0000:65:00.0]-5003:8: ISP System Error - mbx1=1ff5h mbx2=10h mbx3=0h mbx4=0h mbx5=191h mbx6=0h mbx7=0h. qla2xxx [0000:65:00.0]-d01e:8: -> fwdump no buffer qla2xxx [0000:65:00.0]-f03a:8: qla_target(0): System error async event 0x8002 occurred qla2xxx [0000:65:00.0]-00af:8: Performing ISP error recovery - ha=0000000058183fda. BUG: kernel NULL pointer dereference, address: 0000000000000000 PF: supervisor instruction fetch in kernel mode PF: error_code(0x0010) - not-present page PGD 0 P4D 0 Oops: 0010 [#1] SMP CPU: 2 PID: 9446 Comm: qla2xxx_8_dpc Tainted: G O 6.1.133 #1 Hardware name: Supermicro Super Server/X11SPL-F, BIOS 4.2 12/15/2023 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc90001f93dc8 EFLAGS: 00010206 RAX: 0000000000000282 RBX: 0000000000000355 RCX: ffff88810d16a000 RDX: ffff88810dbadaa8 RSI: 0000000000080000 RDI: ffff888169dc38c0 RBP: ffff888169dc38c0 R08: 0000000000000001 R09: 0000000000000045 R10: ffffffffa034bdf0 R11: 0000000000000000 R12: ffff88810800bb40 R13: 0000000000001aa8 R14: ffff888100136610 R15: ffff8881070f7400 FS: 0000000000000000(0000) GS:ffff88bf80080000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000010c8ff006 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die+0x4d/0x8b ? page_fault_oops+0x91/0x180 ? trace_buffer_unlock_commit_regs+0x38/0x1a0 ? exc_page_fault+0x391/0x5e0 ? asm_exc_page_fault+0x22/0x30 __qla2x00_abort_all_cmds+0xcb/0x3e0 [qla2xxx_scst] qla2x00_abort_all_cmds+0x50/0x70 [qla2xxx_scst] qla2x00_abort_isp_cleanup+0x3b7/0x4b0 [qla2xxx_scst] qla2x00_abort_isp+0xfd/0x860 [qla2xxx_scst] qla2x00_do_dpc+0x581/0xa40 [qla2xxx_scst] kthread+0xa8/0xd0 </TASK> Then commit 4475afa2646d ("scsi: qla2xxx: Complete command early within lock") added the spinlock back, because not having the lock caused a race and a crash. But qla2x00_abort_srb() in the switch below already checks for qla2x00_chip_is_down() and handles it the same way, so the code above the switch is now redundant and still buggy in target-mode. Remove it.
CVE-2023-54308 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: ALSA: ymfpci: Create card with device-managed snd_devm_card_new() snd_card_ymfpci_remove() was removed in commit c6e6bb5eab74 ("ALSA: ymfpci: Allocate resources with device-managed APIs"), but the call to snd_card_new() was not replaced with snd_devm_card_new(). Since there was no longer a call to snd_card_free, unloading the module would eventually result in Oops: [697561.532887] BUG: unable to handle page fault for address: ffffffffc0924480 [697561.532893] #PF: supervisor read access in kernel mode [697561.532896] #PF: error_code(0x0000) - not-present page [697561.532899] PGD ae1e15067 P4D ae1e15067 PUD ae1e17067 PMD 11a8f5067 PTE 0 [697561.532905] Oops: 0000 [#1] PREEMPT SMP NOPTI [697561.532909] CPU: 21 PID: 5080 Comm: wireplumber Tainted: G W OE 6.2.7 #1 [697561.532914] Hardware name: System manufacturer System Product Name/TUF GAMING X570-PLUS, BIOS 4408 10/28/2022 [697561.532916] RIP: 0010:try_module_get.part.0+0x1a/0xe0 [697561.532924] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 49 89 fc bf 01 00 00 00 e8 56 3c f8 ff <41> 83 3c 24 02 0f 84 96 00 00 00 41 8b 84 24 30 03 00 00 85 c0 0f [697561.532927] RSP: 0018:ffffbe9b858c3bd8 EFLAGS: 00010246 [697561.532930] RAX: ffff9815d14f1900 RBX: ffff9815c14e6000 RCX: 0000000000000000 [697561.532933] RDX: 0000000000000000 RSI: ffffffffc055092c RDI: ffffffffb3778c1a [697561.532935] RBP: ffffbe9b858c3be8 R08: 0000000000000040 R09: ffff981a1a741380 [697561.532937] R10: ffffbe9b858c3c80 R11: 00000009d56533a6 R12: ffffffffc0924480 [697561.532939] R13: ffff9823439d8500 R14: 0000000000000025 R15: ffff9815cd109f80 [697561.532942] FS: 00007f13084f1f80(0000) GS:ffff9824aef40000(0000) knlGS:0000000000000000 [697561.532945] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [697561.532947] CR2: ffffffffc0924480 CR3: 0000000145344000 CR4: 0000000000350ee0 [697561.532949] Call Trace: [697561.532951] <TASK> [697561.532955] try_module_get+0x13/0x30 [697561.532960] snd_ctl_open+0x61/0x1c0 [snd] [697561.532976] snd_open+0xb4/0x1e0 [snd] [697561.532989] chrdev_open+0xc7/0x240 [697561.532995] ? fsnotify_perm.part.0+0x6e/0x160 [697561.533000] ? __pfx_chrdev_open+0x10/0x10 [697561.533005] do_dentry_open+0x169/0x440 [697561.533009] vfs_open+0x2d/0x40 [697561.533012] path_openat+0xa9d/0x10d0 [697561.533017] ? debug_smp_processor_id+0x17/0x20 [697561.533022] ? trigger_load_balance+0x65/0x370 [697561.533026] do_filp_open+0xb2/0x160 [697561.533032] ? _raw_spin_unlock+0x19/0x40 [697561.533036] ? alloc_fd+0xa9/0x190 [697561.533040] do_sys_openat2+0x9f/0x160 [697561.533044] __x64_sys_openat+0x55/0x90 [697561.533048] do_syscall_64+0x3b/0x90 [697561.533052] entry_SYSCALL_64_after_hwframe+0x72/0xdc [697561.533056] RIP: 0033:0x7f1308a40db4 [697561.533059] Code: 24 20 eb 8f 66 90 44 89 54 24 0c e8 46 68 f8 ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 32 44 89 c7 89 44 24 0c e8 78 68 f8 ff 8b 44 [697561.533062] RSP: 002b:00007ffcce664450 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 [697561.533066] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1308a40db4 [697561.533068] RDX: 0000000000080000 RSI: 00007ffcce664690 RDI: 00000000ffffff9c [697561.533070] RBP: 00007ffcce664690 R08: 0000000000000000 R09: 0000000000000012 [697561.533072] R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000080000 [697561.533074] R13: 00007f13054b069b R14: 0000565209f83200 R15: 0000000000000000 [697561.533078] </TASK>
CVE-2025-68810 1 Linux 1 Linux Kernel 2026-04-15 N/A
In the Linux kernel, the following vulnerability has been resolved: KVM: Disallow toggling KVM_MEM_GUEST_MEMFD on an existing memslot Reject attempts to disable KVM_MEM_GUEST_MEMFD on a memslot that was initially created with a guest_memfd binding, as KVM doesn't support toggling KVM_MEM_GUEST_MEMFD on existing memslots. KVM prevents enabling KVM_MEM_GUEST_MEMFD, but doesn't prevent clearing the flag. Failure to reject the new memslot results in a use-after-free due to KVM not unbinding from the guest_memfd instance. Unbinding on a FLAGS_ONLY change is easy enough, and can/will be done as a hardening measure (in anticipation of KVM supporting dirty logging on guest_memfd at some point), but fixing the use-after-free would only address the immediate symptom. ================================================================== BUG: KASAN: slab-use-after-free in kvm_gmem_release+0x362/0x400 [kvm] Write of size 8 at addr ffff8881111ae908 by task repro/745 CPU: 7 UID: 1000 PID: 745 Comm: repro Not tainted 6.18.0-rc6-115d5de2eef3-next-kasan #3 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: <TASK> dump_stack_lvl+0x51/0x60 print_report+0xcb/0x5c0 kasan_report+0xb4/0xe0 kvm_gmem_release+0x362/0x400 [kvm] __fput+0x2fa/0x9d0 task_work_run+0x12c/0x200 do_exit+0x6ae/0x2100 do_group_exit+0xa8/0x230 __x64_sys_exit_group+0x3a/0x50 x64_sys_call+0x737/0x740 do_syscall_64+0x5b/0x900 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f581f2eac31 </TASK> Allocated by task 745 on cpu 6 at 9.746971s: kasan_save_stack+0x20/0x40 kasan_save_track+0x13/0x50 __kasan_kmalloc+0x77/0x90 kvm_set_memory_region.part.0+0x652/0x1110 [kvm] kvm_vm_ioctl+0x14b0/0x3290 [kvm] __x64_sys_ioctl+0x129/0x1a0 do_syscall_64+0x5b/0x900 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 745 on cpu 6 at 9.747467s: kasan_save_stack+0x20/0x40 kasan_save_track+0x13/0x50 __kasan_save_free_info+0x37/0x50 __kasan_slab_free+0x3b/0x60 kfree+0xf5/0x440 kvm_set_memslot+0x3c2/0x1160 [kvm] kvm_set_memory_region.part.0+0x86a/0x1110 [kvm] kvm_vm_ioctl+0x14b0/0x3290 [kvm] __x64_sys_ioctl+0x129/0x1a0 do_syscall_64+0x5b/0x900 entry_SYSCALL_64_after_hwframe+0x4b/0x53
CVE-2025-68807 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: block: fix race between wbt_enable_default and IO submission When wbt_enable_default() is moved out of queue freezing in elevator_change(), it can cause the wbt inflight counter to become negative (-1), leading to hung tasks in the writeback path. Tasks get stuck in wbt_wait() because the counter is in an inconsistent state. The issue occurs because wbt_enable_default() could race with IO submission, allowing the counter to be decremented before proper initialization. This manifests as: rq_wait[0]: inflight: -1 has_waiters: True rwb_enabled() checks the state, which can be updated exactly between wbt_wait() (rq_qos_throttle()) and wbt_track()(rq_qos_track()), then the inflight counter will become negative. And results in hung task warnings like: task:kworker/u24:39 state:D stack:0 pid:14767 Call Trace: rq_qos_wait+0xb4/0x150 wbt_wait+0xa9/0x100 __rq_qos_throttle+0x24/0x40 blk_mq_submit_bio+0x672/0x7b0 ... Fix this by: 1. Splitting wbt_enable_default() into: - __wbt_enable_default(): Returns true if wbt_init() should be called - wbt_enable_default(): Wrapper for existing callers (no init) - wbt_init_enable_default(): New function that checks and inits WBT 2. Using wbt_init_enable_default() in blk_register_queue() to ensure proper initialization during queue registration 3. Move wbt_init() out of wbt_enable_default() which is only for enabling disabled wbt from bfq and iocost, and wbt_init() isn't needed. Then the original lock warning can be avoided. 4. Removing the ELEVATOR_FLAG_ENABLE_WBT_ON_EXIT flag and its handling code since it's no longer needed This ensures WBT is properly initialized before any IO can be submitted, preventing the counter from going negative.