================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0x1062/0x11f0 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff888046b45f32 by task syz-executor.3/5567 CPU: 0 PID: 5567 Comm: syz-executor.3 Not tainted 5.15.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 sysv_new_inode+0x1062/0x11f0 fs/sysv/ialloc.c:153 sysv_mknod+0x4a/0xe0 fs/sysv/namei.c:53 lookup_open fs/namei.c:3462 [inline] open_last_lookups fs/namei.c:3532 [inline] path_openat+0x130a/0x2f20 fs/namei.c:3739 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x500 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fae0c6c6ee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fae0ac3a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fae0c7fdfa0 RCX: 00007fae0c6c6ee9 RDX: 00000000000026e1 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 00007fae0c71347f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fae0c7fdfa0 R15: 00007ffd222500b8 The buggy address belongs to the page: page:ffffea00011ad140 refcount:0 mapcount:0 mapping:0000000000000000 index:0x100 pfn:0x46b45 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000100 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 0x1101cca(GFP_HIGHUSER_MOVABLE|__GFP_WRITE), pid 12148, ts 520170227900, free_ts 521534883883 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423 __page_cache_alloc+0xd4/0x4a0 mm/filemap.c:1022 pagecache_get_page+0xa91/0x1010 mm/filemap.c:1940 grab_cache_page_write_begin+0x57/0x90 mm/filemap.c:3739 ext4_da_write_begin+0x599/0xb60 fs/ext4/inode.c:2980 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacf/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page_list+0x1f7/0x8e0 mm/page_alloc.c:3433 release_pages+0x1bb9/0x1f40 mm/swap.c:963 __pagevec_release+0x80/0xf0 mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] truncate_inode_pages_range+0x48b/0x1290 mm/truncate.c:329 ext4_evict_inode+0x2ae/0x1100 fs/ext4/inode.c:224 evict+0x2a4/0x620 fs/inode.c:587 do_unlinkat+0x508/0x950 fs/namei.c:4355 __do_sys_unlink fs/namei.c:4396 [inline] __se_sys_unlink fs/namei.c:4394 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4394 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff888046b45e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888046b45e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888046b45f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888046b45f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888046b46000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================