syz.1.252: attempt to access beyond end of device loop1: rw=0, sector=6491536, nr_sectors = 2 limit=128 Buffer I/O error on dev loop1, logical block 3245768, async page read ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0xfc7/0x1160 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff88804fe011ce by task syz.1.252/8136 CPU: 0 UID: 0 PID: 8136 Comm: syz.1.252 Not tainted 6.12.0-syzkaller-00171-g23acd177540d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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 sysv_new_inode+0xfc7/0x1160 fs/sysv/ialloc.c:153 sysv_mknod+0x4e/0xe0 fs/sysv/namei.c:53 lookup_open fs/namei.c:3636 [inline] open_last_lookups fs/namei.c:3735 [inline] path_openat+0x1c03/0x3590 fs/namei.c:3971 do_filp_open+0x235/0x490 fs/namei.c:4001 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_creat fs/open.c:1508 [inline] __se_sys_creat fs/open.c:1502 [inline] __x64_sys_creat+0x123/0x170 fs/open.c:1502 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: 0033:0x7f9281f7e719 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:00007f9282d74038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f9282135f80 RCX: 00007f9281f7e719 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040 RBP: 00007f9281ff175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9282135f80 R15: 00007fff133426a8 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x8f2 pfn:0x4fe01 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea00013f8008 ffffea00013f8088 0000000000000000 raw: 00000000000008f2 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 8119, tgid 8118 (syz.4.248), ts 197894220088, free_ts 198589170648 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x363e/0x3790 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2283 shmem_alloc_folio mm/shmem.c:1774 [inline] shmem_alloc_and_add_folio+0x49b/0x13d0 mm/shmem.c:1813 shmem_get_folio_gfp+0x5a9/0x20a0 mm/shmem.c:2335 shmem_get_folio mm/shmem.c:2441 [inline] shmem_write_begin+0x17e/0x460 mm/shmem.c:3094 generic_perform_write+0x344/0x6d0 mm/filemap.c:4056 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3269 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 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 page last free pid 8119 tgid 8118 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_folios+0xf21/0x1a10 mm/page_alloc.c:2704 folios_put_refs+0x76c/0x860 mm/swap.c:993 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x64c/0x1cf0 mm/shmem.c:1037 shmem_truncate_range mm/shmem.c:1149 [inline] shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1277 evict+0x4e8/0x9a0 fs/inode.c:796 __dentry_kill+0x20d/0x630 fs/dcache.c:625 dput+0x19f/0x2b0 fs/dcache.c:867 __fput+0x5ba/0xa50 fs/file_table.c:458 __do_sys_close fs/open.c:1567 [inline] __se_sys_close fs/open.c:1552 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1552 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 Memory state around the buggy address: ffff88804fe01080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804fe01100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88804fe01180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88804fe01200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804fe01280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================