==================================================================
BUG: KASAN: stack-out-of-bounds in should_fault_in_pages fs/gfs2/file.c:785 [inline]
BUG: KASAN: stack-out-of-bounds in gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070
Read of size 8 at addr ffffc900032ff350 by task syz.4.166/4987

CPU: 0 PID: 4987 Comm: syz.4.166 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 should_fault_in_pages fs/gfs2/file.c:785 [inline]
 gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070
 gfs2_file_write_iter+0x497/0x1240 fs/gfs2/file.c:1166
 __kernel_write+0x51c/0x970 fs/read_write.c:539
 __dump_emit+0x249/0x370 fs/coredump.c:943
 elf_core_dump+0x2757/0x3500 fs/binfmt_elf.c:2237
 do_coredump+0x14c7/0x2ac0 fs/coredump.c:894
 get_signal+0x40a/0x12c0 kernel/signal.c:2886
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1499
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 002b:00002000000002c8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fca56348180 RCX: 00007fca560ce799
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000001000000
RBP: 00007fca56164c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fca56348218 R14: 00007fca56348180 R15: 00007ffc7e331798
 </TASK>


addr ffffc900032ff350 is located in stack of task syz.4.166/4987 at offset 48 in frame:
 __kernel_write+0x0/0x970

this frame has 3 objects:
 [32, 48) 'iov'
 [64, 112) 'kiocb'
 [144, 184) 'iter'

Memory state around the buggy address:
 ffffc900032ff200: 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 00
 ffffc900032ff280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900032ff300: 00 00 00 00 f1 f1 f1 f1 00 00 f2 f2 00 00 00 00
                                                 ^
 ffffc900032ff380: 00 00 f2 f2 f2 f2 00 00 00 00 00 f3 f3 f3 f3 f3
 ffffc900032ff400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================