netlink: 'syz.2.141': attribute type 1 has an invalid length.
netlink: 232 bytes leftover after parsing attributes in process `syz.2.141'.
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BUG: KASAN: use-after-free in sysv_new_block+0x600/0x798 fs/sysv/balloc.c:113
Read of size 4 at addr ffff0000ec3c30c8 by task syz.2.141/4720

CPU: 1 PID: 4720 Comm: syz.2.141 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call trace:
 dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 print_address_description+0x78/0x30c mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xec/0x15c mm/kasan/report.c:451
 __asan_report_load4_noabort+0x44/0x50 mm/kasan/report_generic.c:308
 sysv_new_block+0x600/0x798 fs/sysv/balloc.c:113
 alloc_branch fs/sysv/itree.c:134 [inline]
 get_block+0x208/0x126c fs/sysv/itree.c:253
 __block_write_begin_int+0x3e4/0x1588 fs/buffer.c:2012
 __block_write_begin fs/buffer.c:2062 [inline]
 block_write_begin+0x60/0xdc fs/buffer.c:2122
 sysv_write_begin+0x50/0x98 fs/sysv/itree.c:487
 generic_perform_write+0x204/0x480 mm/filemap.c:3785
 __generic_file_write_iter+0x23c/0x454 mm/filemap.c:3912
 generic_file_write_iter+0xb0/0x1b4 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x7c8/0xa2c fs/read_write.c:594
 ksys_pwrite64 fs/read_write.c:701 [inline]
 __do_sys_pwrite64 fs/read_write.c:711 [inline]
 __se_sys_pwrite64 fs/read_write.c:708 [inline]
 __arm64_sys_pwrite64+0x170/0x200 fs/read_write.c:708
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

The buggy address belongs to the page:
page:00000000010207a9 refcount:0 mapcount:0 mapping:0000000000000000 index:0x100 pfn:0x12c3c3
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003b0f808 fffffc0003b0f108 0000000000000000
raw: 0000000000000100 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ec3c2f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ec3c3000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000ec3c3080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff0000ec3c3100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ec3c3180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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