================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x198/0x1b0 lib/list_debug.c:62 Read of size 8 at addr ffff888022789048 by task syz-executor.2/6451 CPU: 3 PID: 6451 Comm: syz-executor.2 Not tainted 6.6.0-syzkaller-14651-gd2f51b3516da #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 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 __list_del_entry_valid_or_report+0x198/0x1b0 lib/list_debug.c:62 __list_del_entry_valid include/linux/list.h:124 [inline] __list_del_entry include/linux/list.h:215 [inline] list_del include/linux/list.h:229 [inline] ptp_release+0xc4/0x2b0 drivers/ptp/ptp_chardev.c:147 posix_clock_release+0xa4/0x160 kernel/time/posix-clock.c:157 __fput+0x270/0xbb0 fs/file_table.c:394 task_work_run+0x14d/0x240 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x215/0x240 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_fast_syscall_32+0x6d/0xe0 arch/x86/entry/common.c:233 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a RIP: 0023:0xf7f47579 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:00000000f7f215ac EFLAGS: 00000292 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00000000ffffffff RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6450: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_compat_sys_openat fs/open.c:1515 [inline] __se_compat_sys_openat fs/open.c:1513 [inline] __ia32_compat_sys_openat+0x16e/0x200 fs/open.c:1513 do_syscall_32_irqs_on arch/x86/entry/common.c:164 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:230 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a Freed by task 6451: 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+0xc0/0x180 mm/slub.c:3822 ptp_release+0x204/0x2b0 drivers/ptp/ptp_chardev.c:150 posix_clock_release+0xa4/0x160 kernel/time/posix-clock.c:157 __fput+0x270/0xbb0 fs/file_table.c:394 task_work_run+0x14d/0x240 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x215/0x240 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_fast_syscall_32+0x6d/0xe0 arch/x86/entry/common.c:233 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a The buggy address belongs to the object at ffff888022788000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 4168 bytes inside of freed 8192-byte region [ffff888022788000, ffff88802278a000) The buggy address belongs to the physical page: page:ffffea000089e200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22788 head:ffffea000089e200 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888013043180 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000020002 00000001ffffffff 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6450, tgid 6447 (syz-executor.2), ts 1085437228247, free_ts 1083654478173 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 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+0x8c7/0x1580 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+0x131/0x310 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x15d/0x380 mm/slub.c:3502 kmem_cache_zalloc include/linux/slab.h:711 [inline] ext4_alloc_io_end_vec+0x2b/0x1c0 fs/ext4/page-io.c:60 mpage_map_and_submit_extent fs/ext4/inode.c:2217 [inline] ext4_do_writepages+0x15ee/0x3340 fs/ext4/inode.c:2685 ext4_writepages+0x30c/0x780 fs/ext4/inode.c:2774 do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 filemap_fdatawrite_wbc mm/filemap.c:387 [inline] filemap_fdatawrite_wbc+0x144/0x1b0 mm/filemap.c:377 __filemap_fdatawrite_range+0xba/0x100 mm/filemap.c:420 file_write_and_wait_range+0xcc/0x140 mm/filemap.c:778 ext4_sync_file+0x28e/0xe90 fs/ext4/fsync.c:158 vfs_fsync_range+0x141/0x220 fs/sync.c:188 Memory state around the buggy address: ffff888022788f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888022788f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888022789000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888022789080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888022789100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- 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