Hello, syzbot found the following issue on: HEAD commit: aa0743a22936 Merge tag 'net-6.11-rc5' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1071a233980000 kernel config: https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d dashboard link: https://syzkaller.appspot.com/bug?extid=fe399f27b2a7a1482ce0 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/94b014c0070e/disk-aa0743a2.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/7fc82827c24d/vmlinux-aa0743a2.xz kernel image: https://storage.googleapis.com/syzbot-assets/dab734213137/bzImage-aa0743a2.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+fe399f27b2a7a1482ce0@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_inaccessible include/linux/pagemap.h:326 [inline] BUG: KASAN: slab-use-after-free in isolate_migratepages_block+0x2228/0x64f0 mm/compaction.c:1210 Read of size 8 at addr ffff88801fff3f90 by task syz.0.8507/23585 CPU: 1 UID: 0 PID: 23585 Comm: syz.0.8507 Not tainted 6.11.0-rc4-syzkaller-00135-gaa0743a22936 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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 kasan_check_range+0x282/0x290 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_inaccessible include/linux/pagemap.h:326 [inline] isolate_migratepages_block+0x2228/0x64f0 mm/compaction.c:1210 isolate_migratepages mm/compaction.c:2194 [inline] compact_zone+0x32e6/0x4af0 mm/compaction.c:2641 compact_node mm/compaction.c:2935 [inline] compact_nodes mm/compaction.c:2957 [inline] sysctl_compaction_handler+0x496/0x990 mm/compaction.c:3008 proc_sys_call_handler+0x551/0x8b0 fs/proc/proc_sysctl.c:590 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_pwrite64 fs/read_write.c:705 [inline] __do_sys_pwrite64 fs/read_write.c:715 [inline] __se_sys_pwrite64 fs/read_write.c:712 [inline] __x64_sys_pwrite64+0x1aa/0x230 fs/read_write.c:712 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f54d6779e79 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:00007f54d763b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f54d6915f80 RCX: 00007f54d6779e79 RDX: 0000000000000001 RSI: 0000000020000440 RDI: 0000000000000004 RBP: 00007f54d67e7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f54d6915f80 R15: 00007f54d6a3fa38 </TASK> Allocated by task 27: 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:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_lru_noprof+0x139/0x2b0 mm/slub.c:4056 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4622 alloc_inode fs/inode.c:263 [inline] new_inode_pseudo fs/inode.c:1073 [inline] new_inode+0x6e/0x310 fs/inode.c:1092 __shmem_get_inode mm/shmem.c:2658 [inline] shmem_get_inode+0x34a/0xd50 mm/shmem.c:2729 shmem_mknod+0x5f/0x1e0 mm/shmem.c:3426 vfs_mknod+0x36d/0x3b0 fs/namei.c:4088 handle_create drivers/base/devtmpfs.c:219 [inline] handle drivers/base/devtmpfs.c:384 [inline] devtmpfs_work_loop+0x963/0x1040 drivers/base/devtmpfs.c:399 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 24: 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+0xe0/0x150 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:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 rcu_do_batch kernel/rcu/tree.c:2569 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:928 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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+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:3106 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210 destroy_inode fs/inode.c:318 [inline] evict+0x88b/0x950 fs/inode.c:729 do_unlinkat+0x512/0x830 fs/namei.c:4493 __do_sys_unlink fs/namei.c:4534 [inline] __se_sys_unlink fs/namei.c:4532 [inline] __x64_sys_unlink+0x47/0x50 fs/namei.c:4532 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88801fff3ac8 which belongs to the cache shmem_inode_cache of size 1544 The buggy address is located 1224 bytes inside of freed 1544-byte region [ffff88801fff3ac8, ffff88801fff40d0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801fff7590 pfn:0x1fff0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000240 ffff8880172e7140 ffffea0000b81810 ffffea0001dd6610 raw: ffff88801fff7590 0000000000130001 00000001fdffffff 0000000000000000 head: 00fff00000000240 ffff8880172e7140 ffffea0000b81810 ffffea0001dd6610 head: ffff88801fff7590 0000000000130001 00000001fdffffff 0000000000000000 head: 00fff00000000003 ffffea00007ffc01 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 27, tgid 27 (kdevtmpfs), ts 6756474356, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2321 allocate_slab+0x5a/0x2f0 mm/slub.c:2484 new_slab mm/slub.c:2537 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723 __slab_alloc+0x58/0xa0 mm/slub.c:3813 __slab_alloc_node mm/slub.c:3866 [inline] slab_alloc_node mm/slub.c:4025 [inline] kmem_cache_alloc_lru_noprof+0x1c5/0x2b0 mm/slub.c:4056 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4622 alloc_inode fs/inode.c:263 [inline] new_inode_pseudo fs/inode.c:1073 [inline] new_inode+0x6e/0x310 fs/inode.c:1092 __shmem_get_inode mm/shmem.c:2658 [inline] shmem_get_inode+0x34a/0xd50 mm/shmem.c:2729 shmem_mknod+0x5f/0x1e0 mm/shmem.c:3426 vfs_mknod+0x36d/0x3b0 fs/namei.c:4088 handle_create drivers/base/devtmpfs.c:219 [inline] handle drivers/base/devtmpfs.c:384 [inline] devtmpfs_work_loop+0x963/0x1040 drivers/base/devtmpfs.c:399 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441 kthread+0x2f0/0x390 kernel/kthread.c:389 page_owner free stack trace missing Memory state around the buggy address: ffff88801fff3e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fff3f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801fff3f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801fff4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fff4080: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. 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