cgroup: fork rejected by pids controller in /syz2
=====================================================
BUG: KMSAN: uninit-value in io_fixup_rw_res io_uring/rw.c:277 [inline]
BUG: KMSAN: uninit-value in io_rw_fail+0x1a7/0x1b0 io_uring/rw.c:998
 io_fixup_rw_res io_uring/rw.c:277 [inline]
 io_rw_fail+0x1a7/0x1b0 io_uring/rw.c:998
 io_req_defer_failed+0x217/0x3e0 io_uring/io_uring.c:1026
 io_queue_sqe_fallback+0x1f4/0x260 io_uring/io_uring.c:2106
 io_submit_sqe io_uring/io_uring.c:2335 [inline]
 io_submit_sqes+0x2319/0x2e10 io_uring/io_uring.c:2450
 __do_sys_io_uring_enter io_uring/io_uring.c:3458 [inline]
 __se_sys_io_uring_enter+0x4ed/0x4300 io_uring/io_uring.c:3392
 __x64_sys_io_uring_enter+0x11b/0x1a0 io_uring/io_uring.c:3392
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:774
 slab_alloc_node mm/slub.c:3452 [inline]
 __kmem_cache_alloc_node+0x518/0x920 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:966 [inline]
 __kmalloc+0x121/0x3c0 mm/slab_common.c:980
 kmalloc include/linux/slab.h:584 [inline]
 io_alloc_async_data io_uring/io_uring.c:1766 [inline]
 io_req_prep_async+0x384/0x5a0 io_uring/io_uring.c:1787
 io_queue_sqe_fallback+0x95/0x260 io_uring/io_uring.c:2103
 io_submit_sqe io_uring/io_uring.c:2335 [inline]
 io_submit_sqes+0x2319/0x2e10 io_uring/io_uring.c:2450
 __do_sys_io_uring_enter io_uring/io_uring.c:3458 [inline]
 __se_sys_io_uring_enter+0x4ed/0x4300 io_uring/io_uring.c:3392
 __x64_sys_io_uring_enter+0x11b/0x1a0 io_uring/io_uring.c:3392
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 8606 Comm: syz-executor.2 Not tainted 6.3.0-syzkaller-g81af97bdef5e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
=====================================================