================================================================== 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:335 [inline] BUG: KASAN: slab-use-after-free in isolate_migratepages_block+0x3ea4/0x5680 mm/compaction.c:1180 Read of size 8 at addr ffff8880232759b0 by task syz.2.398/7871 CPU: 1 UID: 0 PID: 7871 Comm: syz.2.398 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #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: __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_inaccessible include/linux/pagemap.h:335 [inline] isolate_migratepages_block+0x3ea4/0x5680 mm/compaction.c:1180 isolate_migratepages mm/compaction.c:2164 [inline] compact_zone+0x1a5c/0x4280 mm/compaction.c:2611 compact_node+0x1a2/0x2d0 mm/compaction.c:2910 compact_nodes mm/compaction.c:2932 [inline] sysctl_compaction_handler mm/compaction.c:2983 [inline] sysctl_compaction_handler+0x145/0x220 mm/compaction.c:2970 proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601 iter_file_splice_write+0x90f/0x10b0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x18f/0x6c0 fs/splice.c:1164 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x178/0x250 fs/splice.c:1233 do_sendfile+0xaed/0xe30 fs/read_write.c:1363 __do_compat_sys_sendfile fs/read_write.c:1439 [inline] __se_compat_sys_sendfile fs/read_write.c:1428 [inline] __ia32_compat_sys_sendfile+0x163/0x230 fs/read_write.c:1428 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fd0579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f512655c EFLAGS: 00000296 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000000005 RDX: 00000000200000c0 RSI: 0000000000000009 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 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:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_lru_noprof+0x1c8/0x3b0 mm/slub.c:4187 shmem_alloc_inode+0x25/0x50 mm/shmem.c:4982 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:2876 [inline] shmem_get_inode+0x194/0xf00 mm/shmem.c:2950 shmem_mknod+0x1a8/0x450 mm/shmem.c:3672 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 34: 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:2353 [inline] slab_free mm/slub.c:4613 [inline] kmem_cache_free+0x152/0x4c0 mm/slub.c:4715 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:561 run_ksoftirqd kernel/softirq.c:950 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:942 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] __ia32_sys_unlink+0xc4/0x110 fs/namei.c:4633 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff8880232754e8 which belongs to the cache shmem_inode_cache of size 1544 The buggy address is located 1224 bytes inside of freed 1544-byte region [ffff8880232754e8, ffff888023275af0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888023277590 pfn:0x23270 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: f5(slab) raw: 00fff00000000240 ffff888040489cc0 ffffea00008f5210 ffffea00008cb010 raw: ffff888023277590 0000000000130001 00000001f5000000 0000000000000000 head: 00fff00000000240 ffff888040489cc0 ffffea00008f5210 ffffea00008cb010 head: ffff888023277590 0000000000130001 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea00008c9c01 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 5522885766, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3476 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2269 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2589 [inline] new_slab+0x2c9/0x410 mm/slub.c:2642 ___slab_alloc+0xce2/0x1650 mm/slub.c:3830 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] kmem_cache_alloc_lru_noprof+0xf0/0x3b0 mm/slub.c:4187 shmem_alloc_inode+0x25/0x50 mm/shmem.c:4982 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:2876 [inline] shmem_get_inode+0x194/0xf00 mm/shmem.c:2950 shmem_mknod+0x1a8/0x450 mm/shmem.c:3672 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: ffff888023275880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023275900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888023275980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888023275a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023275a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi