loop0: detected capacity change from 0 to 32768
loop0: detected capacity change from 32768 to 0
loop0: detected capacity change from 0 to 32767
jfs_dirty_inode called on read-only volume
Is remount racy?
jfs_dirty_inode called on read-only volume
Is remount racy?
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: null-ptr-deref in txBeginAnon+0x19a/0x4b0 fs/jfs/jfs_txnmgr.c:465
Read of size 8 at addr 0000000000000040 by task syz.0.0/5105

CPU: 0 UID: 0 PID: 5105 Comm: syz.0.0 Not tainted 6.11.0-rc3-syzkaller-00279-ge5fa841af679 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_report+0xe8/0x550 mm/kasan/report.c:491
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 txBeginAnon+0x19a/0x4b0 fs/jfs/jfs_txnmgr.c:465
 extAlloc+0xf5/0x1010 fs/jfs/jfs_extent.c:78
 jfs_get_block+0x41b/0xe60 fs/jfs/inode.c:248
 __block_write_begin_int+0x50c/0x1a70 fs/buffer.c:2125
 __block_write_begin fs/buffer.c:2174 [inline]
 block_write_begin+0x9b/0x1e0 fs/buffer.c:2235
 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299
 generic_perform_write+0x399/0x840 mm/filemap.c:4019
 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4147
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e595799b9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8e593ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8e59715f80 RCX: 00007f8e595799b9
RDX: 00000000fffffec6 RSI: 0000000020000180 RDI: 0000000000000007
RBP: 00007f8e595e78d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8e59715f80 R15: 00007ffe75ef7518
 </TASK>
==================================================================