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BUG: KMSAN: uninit-value in cmsghdr_from_user_compat_to_kern+0x568/0x10d0 net/compat.c:154
 cmsghdr_from_user_compat_to_kern+0x568/0x10d0 net/compat.c:154
 ____sys_sendmsg+0x22c/0xda0 net/socket.c:2535
 __sys_sendmsg_sock+0x42/0x60 net/socket.c:2639
 io_sendmsg+0x36a/0xe30 io_uring/net.c:544
 io_issue_sqe+0x394/0x1fb0 io_uring/io_uring.c:1737
 io_wq_submit_work+0xaf9/0xdc0 io_uring/io_uring.c:1846
 io_worker_handle_work+0xd11/0x2110 io_uring/io-wq.c:601
 io_wq_worker+0x459/0x1420 io_uring/io-wq.c:655
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 io_sendmsg+0x694/0xe30 io_uring/net.c:542
 io_issue_sqe+0x394/0x1fb0 io_uring/io_uring.c:1737
 io_wq_submit_work+0xaf9/0xdc0 io_uring/io_uring.c:1846
 io_worker_handle_work+0xd11/0x2110 io_uring/io-wq.c:601
 io_wq_worker+0x459/0x1420 io_uring/io-wq.c:655
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 __alloc_frozen_pages_noprof+0x9a7/0xe00 mm/page_alloc.c:4762
 alloc_pages_mpol+0x4cd/0x890 mm/mempolicy.c:2270
 alloc_frozen_pages_noprof+0x1bf/0x1e0 mm/mempolicy.c:2341
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x23a/0x1110 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0x1287/0x3540 mm/slub.c:3826
 __kmem_cache_alloc_bulk mm/slub.c:5045 [inline]
 kmem_cache_alloc_bulk_noprof+0x486/0x1330 mm/slub.c:5117
 __io_alloc_req_refill+0x84/0x5b0 io_uring/io_uring.c:965
 io_alloc_req io_uring/io_uring.h:435 [inline]
 io_submit_sqes+0x90f/0x2ff0 io_uring/io_uring.c:2310
 __do_sys_io_uring_enter io_uring/io_uring.c:3372 [inline]
 __se_sys_io_uring_enter+0x41d/0x4da0 io_uring/io_uring.c:3307
 __ia32_sys_io_uring_enter+0x11d/0x1a0 io_uring/io_uring.c:3307
 ia32_sys_call+0xd59/0x4180 arch/x86/include/generated/asm/syscalls_32.h:427
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 27577 Comm: iou-wrk-27576 Not tainted 6.14.0-rc4-syzkaller-00090-gdd83757f6e68 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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