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BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in dbNextAG+0x14f/0x530 fs/jfs/jfs_dmap.c:622
Read of size 4 at addr ffff88818dc930d8 by task syz-executor.2/6731

CPU: 0 PID: 6731 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report+0x8f/0xa0 mm/kasan/report.c:412
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 dbNextAG+0x14f/0x530 fs/jfs/jfs_dmap.c:622
 diAlloc+0x7ea/0x1440 fs/jfs/jfs_imap.c:1380
 ialloc+0x8c/0x970 fs/jfs/jfs_inode.c:69
 jfs_create.part.0+0x12b/0x880 fs/jfs/namei.c:105
netlink: 60 bytes leftover after parsing attributes in process `syz-executor.4'.
 jfs_create+0x3f/0x60 fs/jfs/namei.c:90
 lookup_open+0x893/0x1a20 fs/namei.c:3235
 do_last fs/namei.c:3327 [inline]
 path_openat+0x1094/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 file_open_name+0x269/0x380 fs/open.c:1032
 filp_open+0x47/0x70 fs/open.c:1052
 do_coredump+0x1fb2/0x2d60 fs/coredump.c:717
 get_signal+0xed9/0x1f70 kernel/signal.c:2583
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7febdc957797
Code: 08 89 3c 24 48 89 4c 24 18 e8 e5 f8 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 48 8b 74 24 08 8b 3c 24 b8 12 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 04 24 e8 15 f9 ff ff 48 8b
RSP: 002b:00007febdaf17f00 EFLAGS: 00000293 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffe5 RBX: 0000000000000353 RCX: 00007febdc957797
RDX: 0000000000000001 RSI: 0000000020008b00 RDI: 000000000000000b
RBP: 000000000000000b R08: 0000000000000000 R09: 0000000000000000
R10: 0030656764697262 R11: 0000000000000293 R12: 000000000000000b
R13: 0000000020000230 R14: 0000000000000002 R15: 00007febdc9efa20

The buggy address belongs to the page:
page:ffffea00063724c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x57ff00000000000()
raw: 057ff00000000000 ffffea00063724c8 ffffea00063724c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88818dc92f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88818dc93000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88818dc93080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff88818dc93100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88818dc93180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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