{"id":"CVE-2025-38106","summary":"io_uring: fix use-after-free of sq-\u003ethread in __io_uring_show_fdinfo()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix use-after-free of sq-\u003ethread in __io_uring_show_fdinfo()\n\nsyzbot reports:\n\nBUG: KASAN: slab-use-after-free in getrusage+0x1109/0x1a60\nRead of size 8 at addr ffff88810de2d2c8 by task a.out/304\n\nCPU: 0 UID: 0 PID: 304 Comm: a.out Not tainted 6.16.0-rc1 #1 PREEMPT(voluntary)\nHardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n dump_stack_lvl+0x53/0x70\n print_report+0xd0/0x670\n ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n ? getrusage+0x1109/0x1a60\n kasan_report+0xce/0x100\n ? getrusage+0x1109/0x1a60\n getrusage+0x1109/0x1a60\n ? __pfx_getrusage+0x10/0x10\n __io_uring_show_fdinfo+0x9fe/0x1790\n ? ksys_read+0xf7/0x1c0\n ? do_syscall_64+0xa4/0x260\n ? vsnprintf+0x591/0x1100\n ? __pfx___io_uring_show_fdinfo+0x10/0x10\n ? __pfx_vsnprintf+0x10/0x10\n ? mutex_trylock+0xcf/0x130\n ? __pfx_mutex_trylock+0x10/0x10\n ? __pfx_show_fd_locks+0x10/0x10\n ? io_uring_show_fdinfo+0x57/0x80\n io_uring_show_fdinfo+0x57/0x80\n seq_show+0x38c/0x690\n seq_read_iter+0x3f7/0x1180\n ? inode_set_ctime_current+0x160/0x4b0\n seq_read+0x271/0x3e0\n ? __pfx_seq_read+0x10/0x10\n ? __pfx__raw_spin_lock+0x10/0x10\n ? __mark_inode_dirty+0x402/0x810\n ? selinux_file_permission+0x368/0x500\n ? file_update_time+0x10f/0x160\n vfs_read+0x177/0xa40\n ? __pfx___handle_mm_fault+0x10/0x10\n ? __pfx_vfs_read+0x10/0x10\n ? mutex_lock+0x81/0xe0\n ? __pfx_mutex_lock+0x10/0x10\n ? fdget_pos+0x24d/0x4b0\n ksys_read+0xf7/0x1c0\n ? __pfx_ksys_read+0x10/0x10\n ? do_user_addr_fault+0x43b/0x9c0\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f0f74170fc9\nCode: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 8b 8\nRSP: 002b:00007fffece049e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000000\nRAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0f74170fc9\nRDX: 0000000000001000 RSI: 00007fffece049f0 RDI: 0000000000000004\nRBP: 00007fffece05ad0 R08: 0000000000000000 R09: 00007fffece04d90\nR10: 0000000000000000 R11: 0000000000000206 R12: 00005651720a1100\nR13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\n \u003c/TASK\u003e\n\nAllocated by task 298:\n kasan_save_stack+0x33/0x60\n kasan_save_track+0x14/0x30\n __kasan_slab_alloc+0x6e/0x70\n kmem_cache_alloc_node_noprof+0xe8/0x330\n copy_process+0x376/0x5e00\n create_io_thread+0xab/0xf0\n io_sq_offload_create+0x9ed/0xf20\n io_uring_setup+0x12b0/0x1cc0\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFreed by task 22:\n kasan_save_stack+0x33/0x60\n kasan_save_track+0x14/0x30\n kasan_save_free_info+0x3b/0x60\n __kasan_slab_free+0x37/0x50\n kmem_cache_free+0xc4/0x360\n rcu_core+0x5ff/0x19f0\n handle_softirqs+0x18c/0x530\n run_ksoftirqd+0x20/0x30\n smpboot_thread_fn+0x287/0x6c0\n kthread+0x30d/0x630\n ret_from_fork+0xef/0x1a0\n ret_from_fork_asm+0x1a/0x30\n\nLast potentially related work creation:\n kasan_save_stack+0x33/0x60\n kasan_record_aux_stack+0x8c/0xa0\n __call_rcu_common.constprop.0+0x68/0x940\n __schedule+0xff2/0x2930\n __cond_resched+0x4c/0x80\n mutex_lock+0x5c/0xe0\n io_uring_del_tctx_node+0xe1/0x2b0\n io_uring_clean_tctx+0xb7/0x160\n io_uring_cancel_generic+0x34e/0x760\n do_exit+0x240/0x2350\n do_group_exit+0xab/0x220\n __x64_sys_exit_group+0x39/0x40\n x64_sys_call+0x1243/0x1840\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nThe buggy address belongs to the object at ffff88810de2cb00\n which belongs to the cache task_struct of size 3712\nThe buggy address is located 1992 bytes inside of\n freed 3712-byte region [ffff88810de2cb00, ffff88810de2d980)\n\nwhich is caused by the task_struct pointed to by sq-\u003ethread being\nreleased while it is being used in the function\n__io_uring_show_fdinfo(). Holding ctx-\u003euring_lock does not prevent ehre\nrelase or exit of sq-\u003ethread.\n\nFix this by assigning and looking up -\u003ethread under RCU, and grabbing a\nreference to the task_struct. This e\n---truncated---","modified":"2026-04-02T12:47:39.912768Z","published":"2025-07-03T08:35:16.215Z","related":["ALSA-2026:3966","ALSA-2026:4012","SUSE-SU-2025:02853-1","SUSE-SU-2025:02997-1","SUSE-SU-2025:03011-1","SUSE-SU-2025:21074-1","SUSE-SU-2025:21139-1","SUSE-SU-2025:21179-1","openSUSE-SU-2025:20081-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38106.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/ac0b8b327a5677dc6fecdf353d808161525b1ff0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/af8c13f9ee040b9a287ba246cf0055f7c77b7cc8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d0932758a0a77b38ba1b39564f3b7aba12407061"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38106.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38106"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3fcb9d17206e31630f802a3ab52081d1342b8ed9"},{"fixed":"af8c13f9ee040b9a287ba246cf0055f7c77b7cc8"},{"fixed":"d0932758a0a77b38ba1b39564f3b7aba12407061"},{"fixed":"ac0b8b327a5677dc6fecdf353d808161525b1ff0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-38106.json"}}],"schema_version":"1.7.5"}