==================================================================
BUG: KASAN: null-ptr-deref in xlog_cil_alloc_shadow_bufs fs/xfs/xfs_log_cil.c:225 [inline]
BUG: KASAN: null-ptr-deref in xlog_cil_commit+0x254/0x1b7c fs/xfs/xfs_log_cil.c:1264
Write of size 104 at addr 0000000000000000 by task syz.4.748/7530

CPU: 0 PID: 7530 Comm: syz.4.748 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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
 __kasan_report mm/kasan/report.c:438 [inline]
 kasan_report+0xe0/0x15c mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x270/0x2b0 mm/kasan/generic.c:189
 memset+0x58/0x88 mm/kasan/shadow.c:44
 xlog_cil_alloc_shadow_bufs fs/xfs/xfs_log_cil.c:225 [inline]
 xlog_cil_commit+0x254/0x1b7c fs/xfs/xfs_log_cil.c:1264
 __xfs_trans_commit+0x628/0xcd4 fs/xfs/xfs_trans.c:881
 xfs_trans_commit+0x24/0x34 fs/xfs/xfs_trans.c:925
 xfs_link+0x5e0/0x8dc fs/xfs/xfs_inode.c:1302
 xfs_vn_link+0x110/0x1e0 fs/xfs/xfs_iops.c:368
 vfs_link+0x5b4/0x744 fs/namei.c:4557
 do_linkat+0x3dc/0x6f8 fs/namei.c:4628
 __do_sys_linkat fs/namei.c:4656 [inline]
 __se_sys_linkat fs/namei.c:4653 [inline]
 __arm64_sys_linkat+0xe4/0x100 fs/namei.c:4653
 __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
==================================================================
Unable to handle kernel paging request at virtual address dfff800000000003
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
[dfff800000000003] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:

CPU: 1 PID: 7530 Comm: syz.4.748 Tainted: G    B             5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : xlog_cil_alloc_shadow_bufs fs/xfs/xfs_log_cil.c:227 [inline]
pc : xlog_cil_commit+0x25c/0x1b7c fs/xfs/xfs_log_cil.c:1264
lr : xlog_cil_alloc_shadow_bufs fs/xfs/xfs_log_cil.c:225 [inline]
lr : xlog_cil_commit+0x254/0x1b7c fs/xfs/xfs_log_cil.c:1264
sp : ffff80001f177780
x29: ffff80001f177880
 x28: 00000000000001c0
 x27: 0000000000000003

x26: 0000000000000000
 x25: ffff0000de3b7580
 x24: ffff0000de3b7510

x23: ffff80001f177820
 x22: 1fffe0001bc76eb0
 x21: 0000000000000003
x20: ffff0000de3b7500 x19: dfff800000000000 x18: 1fffe0003422158e
x17: 1fffe0003422158e x16: ffff8000111a97c4 x15: ffff80000891e164
x14: ffff80000891dd64 x13: ffff8000111a56e8 x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000003 x7 : 0000000000000000 x6 : ffff80000805b058
x5 : ffff0000c1522250 x4 : 0000000000000000 x3 : ffff800008184638
x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000018
Call trace:
 xlog_cil_alloc_shadow_bufs fs/xfs/xfs_log_cil.c:227 [inline]
 xlog_cil_commit+0x25c/0x1b7c fs/xfs/xfs_log_cil.c:1264
 __xfs_trans_commit+0x628/0xcd4 fs/xfs/xfs_trans.c:881
 xfs_trans_commit+0x24/0x34 fs/xfs/xfs_trans.c:925
 xfs_link+0x5e0/0x8dc fs/xfs/xfs_inode.c:1302
 xfs_vn_link+0x110/0x1e0 fs/xfs/xfs_iops.c:368
 vfs_link+0x5b4/0x744 fs/namei.c:4557
 do_linkat+0x3dc/0x6f8 fs/namei.c:4628
 __do_sys_linkat fs/namei.c:4656 [inline]
 __se_sys_linkat fs/namei.c:4653 [inline]
 __arm64_sys_linkat+0xe4/0x100 fs/namei.c:4653
 __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
Code: 93407d02 97b87e10 91006340 d343fc08 (38736908) 
---[ end trace eed35d7190349b22 ]---
----------------
Code disassembly (best guess):
   0:	93407d02 	sxtw	x2, w8
   4:	97b87e10 	bl	0xfffffffffee1f844
   8:	91006340 	add	x0, x26, #0x18
   c:	d343fc08 	lsr	x8, x0, #3
* 10:	38736908 	ldrb	w8, [x8, x19] <-- trapping instruction