RAX: ffffffffffffffda RBX: 00007f3834e6d6d4 RCX: 0000000000455a99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000015
R13: 00000000004bba9e R14: 00000000004c8ad8 R15: 0000000000000000
BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
PGD 800000001659b067 P4D 800000001659b067 PUD 15a50067 PMD 0 
Oops: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 6641 Comm: syz-executor2 Not tainted 4.17.0+ #9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:197 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:142 [inline]
RIP: 0010:PageLocked include/linux/page-flags.h:272 [inline]
RIP: 0010:grow_dev_page fs/buffer.c:942 [inline]
RIP: 0010:grow_buffers fs/buffer.c:1009 [inline]
RIP: 0010:__getblk_slow fs/buffer.c:1036 [inline]
RIP: 0010:__getblk_gfp+0x5bf/0x1630 fs/buffer.c:1316
RSP: 0018:ffff880017f9f730 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000020 RCX: 0000000000000000
RDX: ffff88019e19a618 RSI: 0000000000000000 RDI: 00000000000203ef
RBP: ffff880017f9f878 R08: 0000000001080000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff86575950 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801db428c10
FS:  00007f3834e6d700(0000) GS:ffff88021fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a3eab8 CR3: 000000001221a000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 __bread_gfp+0x11b/0x850 fs/buffer.c:1352
 sb_bread include/linux/buffer_head.h:309 [inline]
 ext4_xattr_block_get fs/ext4/xattr.c:528 [inline]
 ext4_xattr_get+0x43f/0x1010 fs/ext4/xattr.c:651
 ext4_xattr_security_get+0xc8/0xe0 fs/ext4/xattr_security.c:20
 __vfs_getxattr+0x7a6/0x7f0 fs/xattr.c:312
 cap_inode_need_killpriv+0x99/0xd0 security/commoncap.c:307
 security_inode_need_killpriv+0xcf/0x1a0 security/security.c:796
 notify_change+0x7ee/0x1b10 fs/attr.c:250
 chown_common+0x5b3/0x950 fs/open.c:643
 ksys_fchown+0x214/0x2f0 fs/open.c:714
 __do_sys_fchown fs/open.c:724 [inline]
 __se_sys_fchown fs/open.c:722 [inline]
 __x64_sys_fchown+0xd8/0x120 fs/open.c:722
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a99
RSP: 002b:00007f3834e6cc68 EFLAGS: 00000246 ORIG_RAX: 000000000000005d
RAX: ffffffffffffffda RBX: 00007f3834e6d6d4 RCX: 0000000000455a99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000015
R13: 00000000004bba9e R14: 00000000004c8ad8 R15: 0000000000000000
Code: ff ff ff 44 89 e9 e8 91 80 ad ff 49 89 c6 4c 8b ab 20 03 00 00 8b 83 a8 0f 00 00 89 45 d0 49 8d 5e 20 4d 85 ed 0f 85 35 01 00 00 <4d> 8b 7e 20 48 89 9d e0 fe ff ff 48 89 df e8 0e 3c dc ff 48 8b 
RIP: __read_once_size include/linux/compiler.h:197 [inline] RSP: ffff880017f9f730
RIP: compound_head include/linux/page-flags.h:142 [inline] RSP: ffff880017f9f730
RIP: PageLocked include/linux/page-flags.h:272 [inline] RSP: ffff880017f9f730
RIP: grow_dev_page fs/buffer.c:942 [inline] RSP: ffff880017f9f730
RIP: grow_buffers fs/buffer.c:1009 [inline] RSP: ffff880017f9f730
RIP: __getblk_slow fs/buffer.c:1036 [inline] RSP: ffff880017f9f730
RIP: __getblk_gfp+0x5bf/0x1630 fs/buffer.c:1316 RSP: ffff880017f9f730
CR2: 0000000000000020
---[ end trace 29edae35eda5f7c6 ]---