================================================================== BUG: KASAN: slab-use-after-free in task_pgrp include/linux/sched/signal.h:689 [inline] BUG: KASAN: slab-use-after-free in kill_orphaned_pgrp+0x41/0x560 kernel/exit.c:379 Read of size 8 at addr ffff8880233c8908 by task vhost-14812/14813 CPU: 1 PID: 14813 Comm: vhost-14812 Not tainted 6.9.0-rc7-syzkaller-00008-gee5b455b0ada #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 task_pgrp include/linux/sched/signal.h:689 [inline] kill_orphaned_pgrp+0x41/0x560 kernel/exit.c:379 exit_notify kernel/exit.c:739 [inline] do_exit+0x1673/0x27e0 kernel/exit.c:898 vhost_task_fn+0x2ff/0x320 kernel/vhost_task.c:61 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 14533: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3851 [inline] kmem_cache_alloc_node+0x194/0x390 mm/slub.c:3894 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct+0x57/0x7d0 kernel/fork.c:1107 copy_process+0x5d1/0x3df0 kernel/fork.c:2220 kernel_clone+0x226/0x8f0 kernel/fork.c:2797 __do_sys_clone kernel/fork.c:2940 [inline] __se_sys_clone kernel/fork.c:2924 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2924 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 0: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2111 [inline] slab_free mm/slub.c:4286 [inline] kmem_cache_free+0x10b/0x2d0 mm/slub.c:4350 put_task_struct include/linux/sched/task.h:138 [inline] delayed_put_task_struct+0x125/0x2f0 kernel/exit.c:229 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471 handle_softirqs+0x2d6/0x990 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:2734 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:2838 release_task+0x16d2/0x1810 de_thread fs/exec.c:1172 [inline] begin_new_exec+0xfde/0x1ce0 fs/exec.c:1278 load_elf_binary+0xb12/0x2e40 fs/binfmt_elf.c:996 search_binary_handler fs/exec.c:1778 [inline] exec_binprm fs/exec.c:1820 [inline] bprm_execve+0xaf8/0x17c0 fs/exec.c:1872 do_execveat_common+0x553/0x700 fs/exec.c:1979 do_execve fs/exec.c:2053 [inline] __do_sys_execve fs/exec.c:2129 [inline] __se_sys_execve fs/exec.c:2124 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2124 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880233c8000 which belongs to the cache task_struct of size 7424 The buggy address is located 2312 bytes inside of freed 7424-byte region [ffff8880233c8000, ffff8880233c9d00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x233c8 head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888023ccd341 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888015eea500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff888023ccd341 head: 00fff00000000840 ffff888015eea500 dead000000000100 dead000000000122 head: 0000000000000000 0000000000040004 00000001ffffffff ffff888023ccd341 head: 00fff00000000003 ffffea00008cf201 ffffea00008cf248 00000000ffffffff head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1060, tgid -937951101 (kworker/u8:6), ts 1060, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2180 allocate_slab mm/slub.c:2343 [inline] new_slab+0x84/0x2f0 mm/slub.c:2396 ___slab_alloc+0xc73/0x1260 mm/slub.c:3530 __slab_alloc mm/slub.c:3615 [inline] __slab_alloc_node mm/slub.c:3668 [inline] slab_alloc_node mm/slub.c:3841 [inline] kmem_cache_alloc_node+0x24a/0x390 mm/slub.c:3894 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct+0x57/0x7d0 kernel/fork.c:1107 copy_process+0x5d1/0x3df0 kernel/fork.c:2220 kernel_clone+0x226/0x8f0 kernel/fork.c:2797 user_mode_thread+0x132/0x1a0 kernel/fork.c:2875 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:172 process_one_work kernel/workqueue.c:3267 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 page_owner free stack trace missing Memory state around the buggy address: ffff8880233c8800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880233c8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880233c8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880233c8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880233c8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================