================================================================== 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+0x2e1/0x340 kernel/exit.c:379 Read of size 8 at addr ffff88802cf9a6b0 by task vhost-5644/5646 CPU: 1 PID: 5646 Comm: vhost-5644 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 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:377 [inline] print_report+0xc4/0x620 mm/kasan/report.c:488 kasan_report+0xda/0x110 mm/kasan/report.c:601 task_pgrp include/linux/sched/signal.h:689 [inline] kill_orphaned_pgrp+0x2e1/0x340 kernel/exit.c:379 exit_notify kernel/exit.c:739 [inline] do_exit+0x1d13/0x2ad0 kernel/exit.c:891 vhost_task_fn+0x2e4/0x370 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:242 Allocated by task 5409: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:314 [inline] __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3903 alloc_task_struct_node kernel/fork.c:174 [inline] dup_task_struct kernel/fork.c:1104 [inline] copy_process+0x44f/0x97b0 kernel/fork.c:2326 kernel_clone+0xfd/0x930 kernel/fork.c:2901 __do_sys_clone+0xba/0x100 kernel/fork.c:3044 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 22: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:634 poison_slab_object mm/kasan/common.c:241 [inline] __kasan_slab_free+0x121/0x1b0 mm/kasan/common.c:257 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kmem_cache_free+0x129/0x350 mm/slub.c:4363 put_task_struct include/linux/sched/task.h:138 [inline] put_task_struct include/linux/sched/task.h:125 [inline] delayed_put_task_struct+0x21b/0x2c0 kernel/exit.c:229 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x819/0x1680 kernel/rcu/tree.c:2433 __do_softirq+0x21a/0x8de kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:580 __call_rcu_common.constprop.0+0x9a/0x7b0 kernel/rcu/tree.c:2683 put_task_struct_rcu_user kernel/exit.c:235 [inline] put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:232 release_task+0xe7d/0x1b10 kernel/exit.c:285 de_thread fs/exec.c:1157 [inline] begin_new_exec+0x2217/0x3120 fs/exec.c:1263 load_elf_binary+0xa42/0x5b70 fs/binfmt_elf.c:996 search_binary_handler fs/exec.c:1737 [inline] exec_binprm fs/exec.c:1779 [inline] bprm_execve fs/exec.c:1854 [inline] bprm_execve+0x7f9/0x1a90 fs/exec.c:1810 do_execveat_common.isra.0+0x5d3/0x740 fs/exec.c:1962 do_execveat fs/exec.c:2047 [inline] __do_sys_execveat fs/exec.c:2121 [inline] __se_sys_execveat fs/exec.c:2115 [inline] __x64_sys_execveat+0xda/0x120 fs/exec.c:2115 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88802cf99dc0 which belongs to the cache task_struct of size 7360 The buggy address is located 2288 bytes inside of freed 7360-byte region [ffff88802cf99dc0, ffff88802cf9ba80) The buggy address belongs to the physical page: page:ffffea0000b3e600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2cf98 head:ffffea0000b3e600 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802c76c281 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff8880146a1500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080040004 00000001ffffffff ffff88802c76c281 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 5640, tgid 5639 (syz-executor.0), ts 100060700910, free_ts 99971469191 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311 __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2190 [inline] allocate_slab mm/slub.c:2354 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2407 ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625 __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc_node+0x10a/0x340 mm/slub.c:3903 alloc_task_struct_node kernel/fork.c:174 [inline] dup_task_struct kernel/fork.c:1104 [inline] copy_process+0x44f/0x97b0 kernel/fork.c:2326 vhost_task_create+0x17b/0x260 kernel/vhost_task.c:130 vhost_worker_create+0x12a/0x330 drivers/vhost/vhost.c:636 vhost_dev_set_owner+0x5c6/0xa70 drivers/vhost/vhost.c:889 vhost_net_set_owner drivers/vhost/net.c:1687 [inline] vhost_net_ioctl+0x692/0x16e0 drivers/vhost/net.c:1737 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b page last free pid 5627 tgid 5627 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x51f/0xb10 mm/page_alloc.c:2346 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486 __put_partials+0x14c/0x160 mm/slub.c:2922 qlink_free mm/kasan/quarantine.c:160 [inline] qlist_free_all+0x58/0x150 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:324 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_lru+0x142/0x6f0 mm/slub.c:3879 alloc_inode_sb include/linux/fs.h:3019 [inline] ext4_alloc_inode+0x28/0x650 fs/ext4/super.c:1408 alloc_inode+0x5d/0x220 fs/inode.c:260 new_inode_pseudo fs/inode.c:1005 [inline] new_inode+0x22/0x260 fs/inode.c:1031 __ext4_new_inode+0x333/0x5200 fs/ext4/ialloc.c:958 ext4_symlink+0x5d7/0xa20 fs/ext4/namei.c:3396 vfs_symlink fs/namei.c:4480 [inline] vfs_symlink+0x3e4/0x620 fs/namei.c:4464 do_symlinkat+0x25f/0x310 fs/namei.c:4506 __do_sys_symlinkat fs/namei.c:4522 [inline] __se_sys_symlinkat fs/namei.c:4519 [inline] __x64_sys_symlinkat+0x97/0xc0 fs/namei.c:4519 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 Memory state around the buggy address: ffff88802cf9a580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cf9a600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802cf9a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802cf9a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cf9a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================