================================================================== BUG: KASAN: use-after-free in crc_itu_t+0xd2/0xe0 lib/crc-itu-t.c:60 Read of size 1 at addr ffff888073496000 by task syz-executor168/4998 CPU: 0 PID: 4998 Comm: syz-executor168 Not tainted 6.4.0-rc7-syzkaller-00072-gdad9774deaf1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:572 crc_itu_t+0xd2/0xe0 lib/crc-itu-t.c:60 udf_finalize_lvid+0xe0/0x1d0 fs/udf/super.c:1988 udf_sync_fs+0xea/0x150 fs/udf/super.c:2344 sync_filesystem.part.0+0x75/0x1d0 fs/sync.c:56 sync_filesystem+0x8f/0xc0 fs/sync.c:43 generic_shutdown_super+0x74/0x480 fs/super.c:473 kill_block_super+0xa1/0x100 fs/super.c:1407 deactivate_locked_super+0x98/0x160 fs/super.c:331 deactivate_super+0xb1/0xd0 fs/super.c:362 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1177 task_work_run+0x16f/0x270 kernel/task_work.c:179 ptrace_notify+0x118/0x140 kernel/signal.c:2371 ptrace_report_syscall include/linux/ptrace.h:411 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline] syscall_exit_work kernel/entry/common.c:252 [inline] syscall_exit_to_user_mode_prepare+0x129/0x220 kernel/entry/common.c:279 __syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline] syscall_exit_to_user_mode+0xd/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa657993167 Code: 09 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff23ec7e98 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa657993167 RDX: 00007fff23ec7f59 RSI: 000000000000000a RDI: 00007fff23ec7f50 RBP: 00007fff23ec7f50 R08: 00000000ffffffff R09: 00007fff23ec7d30 R10: 00005555566fb683 R11: 0000000000000202 R12: 00007fff23ec8fc0 R13: 00005555566fb5f0 R14: 00007fff23ec7ec0 R15: 0000000000000001 The buggy address belongs to the physical page: page:ffffea0001cd2580 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x73496 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 ffffea0001cd24c8 ffffea0001cd2388 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 4999, tgid 4999 (syz-executor168), ts 40708308403, free_ts 40719661333 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3502 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768 __folio_alloc+0x16/0x40 mm/page_alloc.c:4800 vma_alloc_folio+0x155/0x890 mm/mempolicy.c:2240 shmem_alloc_folio+0x119/0x1e0 mm/shmem.c:1579 shmem_alloc_and_acct_folio+0x15e/0x5d0 mm/shmem.c:1603 shmem_get_folio_gfp+0x9cc/0x1a80 mm/shmem.c:1948 shmem_get_folio mm/shmem.c:2079 [inline] shmem_write_begin+0x14a/0x380 mm/shmem.c:2573 generic_perform_write+0x256/0x570 mm/filemap.c:3929 __generic_file_write_iter+0x2ae/0x500 mm/filemap.c:4057 generic_file_write_iter+0xe3/0x350 mm/filemap.c:4089 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x945/0xd50 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2564 free_unref_page_list+0xe3/0xa70 mm/page_alloc.c:2705 release_pages+0xcd8/0x1380 mm/swap.c:1042 __pagevec_release+0x77/0xe0 mm/swap.c:1062 pagevec_release include/linux/pagevec.h:63 [inline] folio_batch_release include/linux/pagevec.h:132 [inline] shmem_undo_range+0x583/0x1130 mm/shmem.c:954 shmem_truncate_range mm/shmem.c:1049 [inline] shmem_evict_inode+0x32f/0xb60 mm/shmem.c:1164 evict+0x2ed/0x6b0 fs/inode.c:665 iput_final fs/inode.c:1747 [inline] iput.part.0+0x50a/0x740 fs/inode.c:1773 iput+0x5c/0x80 fs/inode.c:1763 dentry_unlink_inode+0x2b1/0x460 fs/dcache.c:401 __dentry_kill+0x3c0/0x640 fs/dcache.c:607 dentry_kill fs/dcache.c:733 [inline] dput+0x865/0xe10 fs/dcache.c:913 __fput+0x3cc/0xa90 fs/file_table.c:329 task_work_run+0x16f/0x270 kernel/task_work.c:179 ptrace_notify+0x118/0x140 kernel/signal.c:2371 ptrace_report_syscall include/linux/ptrace.h:411 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline] syscall_exit_work kernel/entry/common.c:252 [inline] syscall_exit_to_user_mode_prepare+0x129/0x220 kernel/entry/common.c:279 Memory state around the buggy address: ffff888073495f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888073495f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888073496000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888073496080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888073496100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================