loop1: detected capacity change from 0 to 128 VFS: Found a Xenix FS (block size = 1024) on device loop1 ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0xec6/0x1180 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff8880564441ce by task syz.1.220/6922 CPU: 0 UID: 0 PID: 6922 Comm: syz.1.220 Not tainted 6.13.0-rc3-syzkaller-00136-g8faabc041a00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 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 sysv_new_inode+0xec6/0x1180 fs/sysv/ialloc.c:153 sysv_mknod fs/sysv/namei.c:53 [inline] sysv_create+0x20/0xf0 fs/sysv/namei.c:67 lookup_open.isra.0+0x1177/0x14c0 fs/namei.c:3649 open_last_lookups fs/namei.c:3748 [inline] path_openat+0x904/0x2d60 fs/namei.c:3984 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1428 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff570985d29 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:00007ff57185b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ff570b75fa0 RCX: 00007ff570985d29 RDX: 0000000000101042 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007ff570a01aa8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff570b75fa0 R15: 00007ffc84ef1868 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x903 pfn:0x56444 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000903 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 6907, tgid 6906 (syz.1.217), ts 211426486528, free_ts 211734897230 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2269 folio_alloc_mpol_noprof+0x36/0xd0 mm/mempolicy.c:2287 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1794 shmem_alloc_and_add_folio+0x48b/0xc00 mm/shmem.c:1833 shmem_get_folio_gfp+0x689/0x1530 mm/shmem.c:2355 shmem_fault+0x200/0xae0 mm/shmem.c:2556 __do_fault+0x10d/0x490 mm/memory.c:4907 do_read_fault mm/memory.c:5322 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing+0xebd/0x3e00 mm/memory.c:3979 handle_pte_fault mm/memory.c:5801 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x8d9/0x3b50 mm/gup.c:1494 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1932 __mm_populate+0x1d6/0x380 mm/gup.c:2035 page last free pid 6906 tgid 6906 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_folios+0xa7b/0x14f0 mm/page_alloc.c:2704 folios_put_refs+0x587/0x7b0 mm/swap.c:962 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x586/0x1170 mm/shmem.c:1040 shmem_truncate_range mm/shmem.c:1152 [inline] shmem_evict_inode+0x3a3/0xba0 mm/shmem.c:1280 evict+0x40c/0x960 fs/inode.c:796 iput_final fs/inode.c:1946 [inline] iput fs/inode.c:1972 [inline] iput+0x52a/0x890 fs/inode.c:1958 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:422 __dentry_kill+0x1d0/0x600 fs/dcache.c:625 dput.part.0+0x4b1/0x9b0 fs/dcache.c:867 dput+0x1f/0x30 fs/dcache.c:857 __fput+0x515/0xb60 fs/file_table.c:458 task_work_run+0x151/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xadd/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232 Memory state around the buggy address: ffff888056444080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888056444100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888056444180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888056444200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888056444280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== syz.1.220: attempt to access beyond end of device loop1: rw=2049, sector=6491536, nr_sectors = 2 limit=128