loop5: detected capacity change from 0 to 32768 vim2m vim2m.0: Fourcc format (0x47524247) invalid. vim2m vim2m.0: Fourcc format (0x47524247) invalid. general protection fault, probably for non-canonical address 0xdffffc00000000ba: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000005d0-0x00000000000005d7] CPU: 1 PID: 5854 Comm: syz.5.298 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1842 [inline] RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1876 Code: ff df 80 3c 08 00 74 08 48 89 df e8 7f fd f2 fd 41 be d0 05 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 57 fd f2 fd bb 90 00 00 00 49 03 1e RSP: 0018:ffffc90002f5f700 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff888067dfddc8 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8a59a460 RDI: ffffffff8a59a420 RBP: 1ffff1100cfbfbc1 R08: dffffc0000000000 R09: fffffbfff1ff7819 R10: fffffbfff1ff7819 R11: 1ffffffff1ff7818 R12: ffff88807b54a910 R13: ffff888067dfde08 R14: 00000000000005d0 R15: ffff8880212abbac FS: 00007fa7339776c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000f000 CR3: 00000000537fa000 CR4: 00000000003506e0 DR0: 0000000000000001 DR1: 0000000000000003 DR2: 0000000000000e8f DR3: 0000000000000007 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bio_associate_blkg+0x23a/0x340 block/blk-cgroup.c:1904 lbmStartIO+0x204/0x4c0 fs/jfs/jfs_logmgr.c:2130 lbmWrite+0x361/0x480 fs/jfs/jfs_logmgr.c:2079 lmGCwrite fs/jfs/jfs_logmgr.c:-1 [inline] lmGroupCommit+0x5b5/0xb60 fs/jfs/jfs_logmgr.c:695 txCommit+0x4711/0x51c0 fs/jfs/jfs_txnmgr.c:1304 jfs_commit_inode+0x2ec/0x520 fs/jfs/inode.c:108 jfs_fsync+0x181/0x1b0 fs/jfs/file.c:37 generic_write_sync include/linux/fs.h:2989 [inline] generic_file_write_iter+0x157/0x1b0 mm/filemap.c:3948 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa73570fba9 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:00007fa733977038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa735956fa0 RCX: 00007fa73570fba9 RDX: 000000000000fd06 RSI: 00002000000000c0 RDI: 0000000000000009 RBP: 00007fa735792e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa735957038 R14: 00007fa735956fa0 R15: 00007ffed4447cf8 Modules linked in: ---[ end trace b16cc959e016b187 ]--- RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1842 [inline] RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1876 Code: ff df 80 3c 08 00 74 08 48 89 df e8 7f fd f2 fd 41 be d0 05 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 57 fd f2 fd bb 90 00 00 00 49 03 1e RSP: 0018:ffffc90002f5f700 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff888067dfddc8 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8a59a460 RDI: ffffffff8a59a420 RBP: 1ffff1100cfbfbc1 R08: dffffc0000000000 R09: fffffbfff1ff7819 R10: fffffbfff1ff7819 R11: 1ffffffff1ff7818 R12: ffff88807b54a910 R13: ffff888067dfde08 R14: 00000000000005d0 R15: ffff8880212abbac FS: 00007fa7339776c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000f000 CR3: 00000000537fa000 CR4: 00000000003506e0 DR0: 0000000000000001 DR1: 0000000000000003 DR2: 0000000000000e8f DR3: 0000000000000007 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: df 80 3c 08 00 74 filds 0x7400083c(%rax) 6: 08 48 89 or %cl,-0x77(%rax) 9: df e8 fucomip %st(0),%st b: 7f fd jg 0xa d: f2 fd repnz std f: 41 be d0 05 00 00 mov $0x5d0,%r14d 15: 4c 03 33 add (%rbx),%r14 18: 4c 89 f0 mov %r14,%rax 1b: 48 c1 e8 03 shr $0x3,%rax 1f: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 26: fc ff df * 29: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2d: 74 08 je 0x37 2f: 4c 89 f7 mov %r14,%rdi 32: e8 57 fd f2 fd call 0xfdf2fd8e 37: bb 90 00 00 00 mov $0x90,%ebx 3c: 49 03 1e add (%r14),%rbx