loop0: detected capacity change from 0 to 32768
loop0: detected capacity change from 32768 to 0
syz.0.0: attempt to access beyond end of device
loop0: rw=1, sector=128, nr_sectors = 8 limit=0
metapage_write_end_io: I/O error
syz.0.0: attempt to access beyond end of device
loop0: rw=1, sector=256, nr_sectors = 8 limit=0
metapage_write_end_io: I/O error
syz.0.0: attempt to access beyond end of device
loop0: rw=1, sector=88, nr_sectors = 8 limit=0
metapage_write_end_io: I/O error
syz.0.0: attempt to access beyond end of device
loop0: rw=1, sector=104, nr_sectors = 8 limit=0
metapage_write_end_io: I/O error
syz.0.0: attempt to access beyond end of device
loop0: rw=0, sector=64, nr_sectors = 8 limit=0
syz.0.0: attempt to access beyond end of device
loop0: rw=0, sector=120, nr_sectors = 8 limit=0
syz.0.0: attempt to access beyond end of device
loop0: rw=2049, sector=30744, nr_sectors = 8 limit=0
lbmIODone: I/O error in JFS log
syz.0.0: attempt to access beyond end of device
loop0: rw=0, sector=30728, nr_sectors = 8 limit=0
lbmIODone: I/O error in JFS log
syz.0.0: attempt to access beyond end of device
loop0: rw=2049, sector=30728, nr_sectors = 8 limit=0
lbmIODone: I/O error in JFS log
lmLogShutdown: exit(-5)
syz.0.0: attempt to access beyond end of device
loop0: rw=524288, sector=272, nr_sectors = 8 limit=0
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.0.0/5320

CPU: 0 UID: 0 PID: 5320 Comm: syz.0.0 Not tainted 6.12.0-rc5-syzkaller-00044-gc1e939a21eb1 #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:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 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:2121
 block_write_begin+0x8f/0x120 fs/buffer.c:2231
 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299
 generic_perform_write+0x344/0x6d0 mm/filemap.c:4054
 generic_file_write_iter+0xae/0x310 mm/filemap.c:4181
 do_iter_readv_writev+0x600/0x880
 vfs_writev+0x376/0xba0 fs/read_write.c:1064
 do_pwritev fs/read_write.c:1165 [inline]
 __do_sys_pwritev2 fs/read_write.c:1224 [inline]
 __se_sys_pwritev2+0x1ca/0x2d0 fs/read_write.c:1215
 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: 0033:0x7faef997e719
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:00007faef97ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007faef9b35f80 RCX: 00007faef997e719
RDX: 0000000000000001 RSI: 00000000200006c0 RDI: 0000000000000005
RBP: 00007faef99f132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000100000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007faef9b35f80 R15: 00007fffaa1f9c58
 </TASK>
==================================================================