================================================================== BUG: KASAN: slab-use-after-free in task_pgrp include/linux/sched/signal.h:694 [inline] BUG: KASAN: slab-use-after-free in kill_orphaned_pgrp+0x2e1/0x340 kernel/exit.c:376 Read of size 8 at addr ffff88802d78a6b8 by task vhost-16506/16518 CPU: 0 PID: 16518 Comm: vhost-16506 Not tainted 6.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 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 task_pgrp include/linux/sched/signal.h:694 [inline] kill_orphaned_pgrp+0x2e1/0x340 kernel/exit.c:376 exit_notify kernel/exit.c:737 [inline] do_exit+0x1cb5/0x2a20 kernel/exit.c:894 vhost_task_fn+0x2e6/0x370 kernel/vhost_task.c:61 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Allocated by task 5090: 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+0x185/0x3f0 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x7400 kernel/fork.c:2327 kernel_clone+0xfd/0x930 kernel/fork.c:2909 __do_sys_clone+0xba/0x100 kernel/fork.c:3052 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 Freed by task 42: 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+0x246/0x2c0 kernel/exit.c:226 rcu_do_batch kernel/rcu/tree.c:2139 [inline] rcu_core+0x7fb/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 release_task+0xf0a/0x1b90 kernel/exit.c:282 de_thread fs/exec.c:1158 [inline] begin_new_exec+0x226c/0x3110 fs/exec.c:1264 load_elf_binary+0x8ec/0x5c40 fs/binfmt_elf.c:1001 search_binary_handler fs/exec.c:1739 [inline] exec_binprm fs/exec.c:1781 [inline] bprm_execve fs/exec.c:1856 [inline] bprm_execve+0x80a/0x1a50 fs/exec.c:1812 do_execveat_common.isra.0+0x5d3/0x740 fs/exec.c:1964 do_execve fs/exec.c:2038 [inline] __do_sys_execve fs/exec.c:2114 [inline] __se_sys_execve fs/exec.c:2109 [inline] __x64_sys_execve+0x8c/0xb0 fs/exec.c:2109 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 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 __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+0xee9/0x59f0 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 The buggy address belongs to the object at ffff88802d789dc0 which belongs to the cache task_struct of size 7360 The buggy address is located 2296 bytes inside of freed 7360-byte region [ffff88802d789dc0, ffff88802d78ba80) The buggy address belongs to the physical page: page:ffffea0000b5e200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2d788 head:ffffea0000b5e200 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888075f26101 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014e49500 ffffea0001e00e00 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff888075f26101 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 5278, tgid 5278 (syz-executor.3), ts 190312746205, free_ts 190291479937 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:2298 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+0x8be/0x1570 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+0x137/0x3f0 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x7400 kernel/fork.c:2327 kernel_clone+0xfd/0x930 kernel/fork.c:2909 __do_sys_clone3+0x1f1/0x260 kernel/fork.c:3210 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 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 __folio_put+0xeb/0x110 mm/swap.c:127 folio_put include/linux/mm.h:1475 [inline] put_page include/linux/mm.h:1544 [inline] do_exit+0x2332/0x2a20 kernel/exit.c:913 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 get_signal+0x23d1/0x27b0 kernel/signal.c:2892 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88802d78a580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d78a600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802d78a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802d78a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d78a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================