syz.4.17: attempt to access beyond end of device
loop4: rw=0, sector=6491536, nr_sectors = 2 limit=128
Buffer I/O error on dev loop4, 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 ffff88805a25f1ce by task syz.4.17/6007

CPU: 1 UID: 0 PID: 6007 Comm: syz.4.17 Not tainted 6.13.0-rc3-syzkaller-00082-gbaaa2567a712 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Call Trace:
 <TASK>
 __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:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 sysv_new_inode+0xfc7/0x1160 fs/sysv/ialloc.c:153
 sysv_mknod+0x4e/0xe0 fs/sysv/namei.c:53
 vfs_mknod+0x36d/0x3b0 fs/namei.c:4189
 do_mknodat+0x3ec/0x5b0
 __do_sys_mknodat fs/namei.c:4267 [inline]
 __se_sys_mknodat fs/namei.c:4264 [inline]
 __x64_sys_mknodat+0xa7/0xc0 fs/namei.c:4264
 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: 0033:0x7f88e3f85d29
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:00007f88e4e2f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000103
RAX: ffffffffffffffda RBX: 00007f88e4175fa0 RCX: 00007f88e3f85d29
RDX: 00000000000061c0 RSI: 0000000020000180 RDI: ffffffffffffff9c
RBP: 00007f88e4001aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f88e4175fa0 R15: 00007ffdc78413b8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xad0 pfn:0x5a25f
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000ad0 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 6007, tgid 6006 (syz.4.17), ts 70863769295, free_ts 71021636910
 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+0x3651/0x37a0 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2287
 shmem_alloc_folio mm/shmem.c:1794 [inline]
 shmem_alloc_and_add_folio+0x4a0/0x1080 mm/shmem.c:1833
 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2355
 shmem_get_folio mm/shmem.c:2461 [inline]
 shmem_write_begin+0x165/0x350 mm/shmem.c:3117
 generic_perform_write+0x346/0x990 mm/filemap.c:4055
 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3293
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:679
 ksys_write+0x18f/0x2b0 fs/read_write.c:731
 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 6007 tgid 6006 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_folios+0xe23/0x1890 mm/page_alloc.c:2704
 folios_put_refs+0x76c/0x860 mm/swap.c:962
 folio_batch_release include/linux/pagevec.h:101 [inline]
 shmem_undo_range+0x593/0x1820 mm/shmem.c:1040
 shmem_truncate_range mm/shmem.c:1152 [inline]
 shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1280
 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:1554 [inline]
 __se_sys_close fs/open.c:1539 [inline]
 __x64_sys_close+0x7f/0x110 fs/open.c:1539
 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:
 ffff88805a25f080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805a25f100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88805a25f180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff88805a25f200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805a25f280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================