================================================================== BUG: KASAN: slab-use-after-free in min_deadline_update kernel/sched/fair.c:818 [inline] BUG: KASAN: slab-use-after-free in min_deadline_cb_propagate kernel/sched/fair.c:825 [inline] BUG: KASAN: slab-use-after-free in reweight_entity+0x8c7/0xa60 kernel/sched/fair.c:3660 Read of size 8 at addr ffff88803dd6bc28 by task syz-executor.1/25012 CPU: 1 PID: 25012 Comm: syz-executor.1 Not tainted 6.6.0-rc6-syzkaller-00285-g9c5d00cb7b6b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 min_deadline_update kernel/sched/fair.c:818 [inline] min_deadline_cb_propagate kernel/sched/fair.c:825 [inline] reweight_entity+0x8c7/0xa60 kernel/sched/fair.c:3660 entity_tick kernel/sched/fair.c:5317 [inline] task_tick_fair+0xee/0xcd0 kernel/sched/fair.c:12392 scheduler_tick+0x210/0x650 kernel/sched/core.c:5657 update_process_times+0x19f/0x220 kernel/time/timer.c:2076 tick_sched_handle+0x8e/0x170 kernel/time/tick-sched.c:254 tick_sched_timer+0xe9/0x110 kernel/time/tick-sched.c:1492 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x647/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline] __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__sanitizer_cov_trace_pc+0x3b/0x70 kernel/kcov.c:207 Code: 81 e1 00 01 00 00 65 48 8b 14 25 c0 bc 03 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 04 16 00 00 85 c0 74 2b 8b 82 e0 15 00 00 <83> f8 02 75 20 48 8b 8a e8 15 00 00 8b 92 e4 15 00 00 48 8b 01 48 RSP: 0018:ffffc9000322f808 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88803be29c80 RCX: 0000000000000000 RDX: ffff88807c251dc0 RSI: ffffffff882bd27e RDI: ffff88803be29c80 RBP: ffff8880824e4000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88802d988000 R15: ffff8880824e4528 refcount_read include/linux/refcount.h:147 [inline] skb_unref include/linux/skbuff.h:1217 [inline] consume_skb+0x1e/0x170 net/core/skbuff.c:1279 __unix_dgram_recvmsg+0x80f/0xe70 net/unix/af_unix.c:2442 unix_dgram_recvmsg+0xc3/0xf0 net/unix/af_unix.c:2459 sock_recvmsg_nosec net/socket.c:1044 [inline] ____sys_recvmsg+0x4ab/0x5c0 net/socket.c:2775 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2819 do_recvmmsg+0x2af/0x740 net/socket.c:2913 __sys_recvmmsg net/socket.c:2992 [inline] __do_sys_recvmmsg net/socket.c:3015 [inline] __se_sys_recvmmsg net/socket.c:3008 [inline] __x64_sys_recvmmsg+0x235/0x290 net/socket.c:3008 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f965c47cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f965d10e0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f965c59c050 RCX: 00007f965c47cae9 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f965c4c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f965c59c050 R15: 00007ffded596fb8 Allocated by task 7065: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3f0 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x73f0 kernel/fork.c:2327 kernel_clone+0xfd/0x920 kernel/fork.c:2909 user_mode_thread+0xb4/0xf0 kernel/fork.c:2987 call_usermodehelper_exec_sync kernel/umh.c:133 [inline] call_usermodehelper_exec_work+0x6b/0x170 kernel/umh.c:164 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Freed by task 16: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] kmem_cache_free+0xf0/0x480 mm/slub.c:3831 put_task_struct include/linux/sched/task.h:136 [inline] put_task_struct include/linux/sched/task.h:123 [inline] delayed_put_task_struct+0x21b/0x2b0 kernel/exit.c:226 rcu_do_batch kernel/rcu/tree.c:2139 [inline] rcu_core+0x805/0x1bb0 kernel/rcu/tree.c:2403 __do_softirq+0x218/0x965 kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653 put_task_struct_rcu_user kernel/exit.c:232 [inline] put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:229 context_switch kernel/sched/core.c:5385 [inline] __schedule+0xee9/0x5a10 kernel/sched/core.c:6695 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7007 irqentry_exit+0x35/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 task_work_add+0x88/0x2a0 kernel/task_work.c:48 scheduler_tick+0x228/0x650 kernel/sched/core.c:5662 update_process_times+0x19f/0x220 kernel/time/timer.c:2076 tick_sched_handle+0x8e/0x170 kernel/time/tick-sched.c:254 tick_sched_timer+0xe9/0x110 kernel/time/tick-sched.c:1492 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x647/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline] __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 The buggy address belongs to the object at ffff88803dd6bb80 which belongs to the cache task_struct of size 7360 The buggy address is located 168 bytes inside of freed 7360-byte region [ffff88803dd6bb80, ffff88803dd6d840) The buggy address belongs to the physical page: page:ffffea0000f75a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3dd68 head:ffffea0000f75a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888017313781 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014e43500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff888017313781 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 2817, tgid 2817 (kworker/u4:7), ts 2026050898185, free_ts 2026031309096 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2297 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] kmem_cache_alloc_node+0x132/0x3f0 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x73f0 kernel/fork.c:2327 kernel_clone+0xfd/0x920 kernel/fork.c:2909 user_mode_thread+0xb4/0xf0 kernel/fork.c:2987 call_usermodehelper_exec_sync kernel/umh.c:133 [inline] call_usermodehelper_exec_work+0x6b/0x170 kernel/umh.c:164 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 skb_free_frag include/linux/skbuff.h:3260 [inline] skb_free_head+0xa6/0x1b0 net/core/skbuff.c:955 skb_release_data+0x5ba/0x870 net/core/skbuff.c:987 skb_release_all net/core/skbuff.c:1053 [inline] __kfree_skb net/core/skbuff.c:1067 [inline] skb_attempt_defer_free+0x3bc/0x570 net/core/skbuff.c:6817 tcp_eat_recv_skb net/ipv4/tcp.c:1509 [inline] tcp_recvmsg_locked+0x10a8/0x24a0 net/ipv4/tcp.c:2520 tcp_recvmsg+0x12e/0x670 net/ipv4/tcp.c:2566 inet_recvmsg+0x114/0x630 net/ipv4/af_inet.c:878 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg+0xe2/0x170 net/socket.c:1066 sock_read_iter+0x2c3/0x3c0 net/socket.c:1136 call_read_iter include/linux/fs.h:1950 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7ef/0x930 fs/read_write.c:470 ksys_read+0x1f0/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88803dd6bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803dd6bb80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803dd6bc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803dd6bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803dd6bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 81 e1 00 01 00 00 and $0x100,%ecx 6: 65 48 8b 14 25 c0 bc mov %gs:0x3bcc0,%rdx d: 03 00 f: a9 00 01 ff 00 test $0xff0100,%eax 14: 74 0e je 0x24 16: 85 c9 test %ecx,%ecx 18: 74 35 je 0x4f 1a: 8b 82 04 16 00 00 mov 0x1604(%rdx),%eax 20: 85 c0 test %eax,%eax 22: 74 2b je 0x4f 24: 8b 82 e0 15 00 00 mov 0x15e0(%rdx),%eax * 2a: 83 f8 02 cmp $0x2,%eax <-- trapping instruction 2d: 75 20 jne 0x4f 2f: 48 8b 8a e8 15 00 00 mov 0x15e8(%rdx),%rcx 36: 8b 92 e4 15 00 00 mov 0x15e4(%rdx),%edx 3c: 48 8b 01 mov (%rcx),%rax 3f: 48 rex.W