Hello, syzbot found the following issue on: HEAD commit: 2ba9f676d0a2 Merge tag 'drm-next-2024-11-29' of https://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17d56d30580000 kernel config: https://syzkaller.appspot.com/x/.config?x=92c00fea95836451 dashboard link: https://syzkaller.appspot.com/bug?extid=2f574f2471415b81417e compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-2ba9f676.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/67b607be891b/vmlinux-2ba9f676.xz kernel image: https://storage.googleapis.com/syzbot-assets/b142ef38c0ac/bzImage-2ba9f676.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2f574f2471415b81417e@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: slab-use-after-free in mapping_unevictable include/linux/pagemap.h:269 [inline] BUG: KASAN: slab-use-after-free in folio_evictable mm/internal.h:435 [inline] BUG: KASAN: slab-use-after-free in lru_add+0x192/0xd70 mm/swap.c:136 Read of size 8 at addr ffff888024b24618 by task syz.7.1236/11255 CPU: 0 UID: 0 PID: 11255 Comm: syz.7.1236 Not tainted 6.12.0-syzkaller-11677-g2ba9f676d0a2 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] mapping_unevictable include/linux/pagemap.h:269 [inline] folio_evictable mm/internal.h:435 [inline] lru_add+0x192/0xd70 mm/swap.c:136 folio_batch_move_lru+0x113/0x3b0 mm/swap.c:168 lru_add_drain_cpu+0x521/0x810 mm/swap.c:616 lru_add_drain+0x109/0x440 mm/swap.c:698 vms_clear_ptes+0x1f8/0x780 mm/vma.c:1133 vms_clean_up_area mm/vma.c:1155 [inline] __mmap_prepare mm/vma.c:2278 [inline] __mmap_region+0x4c9/0x2670 mm/vma.c:2443 mmap_region+0x127/0x320 mm/mmap.c:1347 do_mmap+0xc00/0xfc0 mm/mmap.c:496 vm_mmap_pgoff+0x1ba/0x360 mm/util.c:580 ksys_mmap_pgoff+0x1c8/0x5c0 mm/mmap.c:542 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f26a0980849 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f26a1845058 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f26a0b45fa0 RCX: 00007f26a0980849 RDX: 0000000000000002 RSI: 0000000000800000 RDI: 0000000020800000 RBP: 00007f26a09f3986 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000042032 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f26a0b45fa0 R15: 00007ffd234568e8 </TASK> Allocated by task 37: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_lru_noprof+0x226/0x3d0 mm/slub.c:4172 shmem_alloc_inode+0x25/0x50 mm/shmem.c:4980 alloc_inode+0x5d/0x230 fs/inode.c:336 new_inode_pseudo fs/inode.c:1174 [inline] new_inode+0x22/0x210 fs/inode.c:1193 __shmem_get_inode mm/shmem.c:2874 [inline] shmem_get_inode+0x194/0xf00 mm/shmem.c:2948 shmem_mknod+0x1a8/0x450 mm/shmem.c:3670 vfs_mknod+0x5d7/0x8e0 fs/namei.c:4189 handle_create drivers/base/devtmpfs.c:219 [inline] handle drivers/base/devtmpfs.c:384 [inline] devtmpfs_work_loop+0x1a8/0x7d0 drivers/base/devtmpfs.c:399 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 29: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x152/0x4c0 mm/slub.c:4700 i_callback+0x43/0x70 fs/inode.c:325 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2823 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 run_ksoftirqd kernel/softirq.c:943 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:935 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:544 __call_rcu_common.constprop.0+0x99/0x7a0 kernel/rcu/tree.c:3086 destroy_inode+0x12c/0x1b0 fs/inode.c:391 evict+0x5ed/0x960 fs/inode.c:827 iput_final fs/inode.c:1946 [inline] iput fs/inode.c:1972 [inline] iput+0x52a/0x890 fs/inode.c:1958 do_unlinkat+0x5c3/0x760 fs/namei.c:4594 __do_sys_unlink fs/namei.c:4635 [inline] __se_sys_unlink fs/namei.c:4633 [inline] __x64_sys_unlink+0xc5/0x110 fs/namei.c:4633 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888024b24150 which belongs to the cache shmem_inode_cache of size 1544 The buggy address is located 1224 bytes inside of freed 1544-byte region [ffff888024b24150, ffff888024b24758) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24b20 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ca8e780 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000130013 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ca8e780 dead000000000122 0000000000000000 head: 0000000000000000 0000000000130013 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea000092c801 ffffffffffffffff 0000000000000000 head: 0000000000000008 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 37, tgid 37 (kdevtmpfs), ts 6023947933, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:2408 [inline] allocate_slab mm/slub.c:2574 [inline] new_slab+0x2c9/0x410 mm/slub.c:2627 ___slab_alloc+0xdac/0x1870 mm/slub.c:3815 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] kmem_cache_alloc_lru_noprof+0xff/0x3d0 mm/slub.c:4172 shmem_alloc_inode+0x25/0x50 mm/shmem.c:4980 alloc_inode+0x5d/0x230 fs/inode.c:336 new_inode_pseudo fs/inode.c:1174 [inline] new_inode+0x22/0x210 fs/inode.c:1193 __shmem_get_inode mm/shmem.c:2874 [inline] shmem_get_inode+0x194/0xf00 mm/shmem.c:2948 shmem_mknod+0x1a8/0x450 mm/shmem.c:3670 vfs_mknod+0x5d7/0x8e0 fs/namei.c:4189 handle_create drivers/base/devtmpfs.c:219 [inline] handle drivers/base/devtmpfs.c:384 [inline] devtmpfs_work_loop+0x1a8/0x7d0 drivers/base/devtmpfs.c:399 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441 page_owner free stack trace missing Memory state around the buggy address: ffff888024b24500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024b24580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888024b24600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024b24680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024b24700: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup