loop0: detected capacity change from 0 to 32768 lmLogOpen: exit(-6) 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.0.0/5320 CPU: 0 UID: 0 PID: 5320 Comm: syz.0.0 Not tainted 6.14.0-rc4-syzkaller #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: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_report+0xe3/0x5b0 mm/kasan/report.c:524 kasan_report+0x143/0x180 mm/kasan/report.c:634 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+0x692/0x19a0 fs/buffer.c:2116 block_write_begin+0x8f/0x120 fs/buffer.c:2226 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299 generic_perform_write+0x346/0x990 mm/filemap.c:4189 generic_file_write_iter+0x10c/0x5b0 mm/filemap.c:4316 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_pwrite64 fs/read_write.c:786 [inline] __do_sys_pwrite64 fs/read_write.c:794 [inline] __se_sys_pwrite64 fs/read_write.c:791 [inline] __x64_sys_pwrite64+0x1ac/0x240 fs/read_write.c:791 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: 0033:0x7f64c158d169 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:00007f64c2305038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f64c17a5fa0 RCX: 00007f64c158d169 RDX: 0000000000000001 RSI: 0000400000003a80 RDI: 0000000000000005 RBP: 00007f64c160e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008000c61 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f64c17a5fa0 R15: 00007ffda566a788 ==================================================================