Hi all, While fuzzing with trinity inside a KVM tools guest running the latest -next kernel, I've stumbled on the following spew: [ 2435.025476] BUG: unable to handle kernel paging request at ffff88056730bfd4 [ 2435.033434] IP: memcpy (arch/x86/lib/memcpy_64.S:160) [ 2435.034378] PGD 145c3067 PUD a6e3e5067 PMD a6e2ab067 PTE 800000056730b060 [ 2435.035052] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN [ 2435.035052] Dumping ftrace buffer: [ 2435.035052] (ftrace buffer empty) [ 2435.035052] Modules linked in: [ 2435.035052] CPU: 24 PID: 26772 Comm: trinity-c611 Not tainted 3.17.0-next-20141010-sasha-00053-g16471e7-dirty #1379 [ 2435.035052] task: ffff880226ec3000 ti: ffff88021a9c8000 task.ti: ffff88021a9c8000 [ 2435.035052] RIP: memcpy (arch/x86/lib/memcpy_64.S:160) [ 2435.035052] RSP: 0018:ffff88021a9cb4d0 EFLAGS: 00010246 [ 2435.035052] RAX: ffff88021a9cb544 RBX: 0000000000000004 RCX: ffff88056730bfd4 [ 2435.035052] RDX: 0000000000000004 RSI: ffff88056730bfd4 RDI: ffff88021a9cb544 [ 2435.035052] RBP: ffff88021a9cb528 R08: dfffe90000000001 R09: ffff88021a9cb547 [ 2435.035052] R10: 1ffff100435396a8 R11: 1ffff100435396a8 R12: 0000000000000004 [ 2435.035052] R13: ffff880630e8b560 R14: ffff88021a9cb544 R15: 0000000000000004 [ 2435.035052] FS: 00007ff4c9a4d700(0000) GS:ffff88006dc00000(0000) knlGS:0000000000000000 [ 2435.035052] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2435.035052] CR2: ffff88056730bfd4 CR3: 000000024a2e6000 CR4: 00000000000006a0 [ 2435.035052] Stack: [ 2435.035052] ffffffff8b6c6897 ffff880000000000 cccccccccccccccd 0000160000000000 [ 2435.035052] ffff88056730bfd4 ffff88021a9cb518 ffff880630e8b4d0 ffff88021a9cb58a [ 2435.035052] ffff88024f075668 0000000000000014 0000000000000003 ffff88021a9cb568 [ 2435.035052] Call Trace: [ 2435.035052] hfsplus_brec_lenoff (include/uapi/linux/swab.h:49 fs/hfsplus/brec.c:26) [ 2435.035052] __hfsplus_brec_find (fs/hfsplus/bfind.c:130) [ 2435.035052] hfsplus_brec_find (fs/hfsplus/bfind.c:196) [ 2435.035052] hfsplus_brec_read (fs/hfsplus/bfind.c:224) [ 2435.035052] hfsplus_find_cat (fs/hfsplus/catalog.c:202) [ 2435.035052] hfsplus_iget (fs/hfsplus/super.c:79) [ 2435.035052] hfsplus_lookup (fs/hfsplus/dir.c:118) [ 2435.035052] lookup_real (fs/namei.c:1345) [ 2435.035052] __lookup_hash (fs/namei.c:1364) [ 2435.093450] walk_component (fs/namei.c:1471 fs/namei.c:1550) [ 2435.094918] path_lookupat (fs/namei.c:1925 fs/namei.c:1959) [ 2435.094918] filename_lookup (fs/namei.c:1998) [ 2435.094918] user_path_at_empty (fs/namei.c:2150) [ 2435.094918] user_path_at (fs/namei.c:2161) [ 2435.094918] SyS_chown (fs/open.c:606 fs/open.c:591 fs/open.c:625 fs/open.c:623) [ 2435.094918] tracesys_phase2 (arch/x86/kernel/entry_64.S:529) [ 2435.094918] Code: 89 5c 17 f8 c3 90 83 fa 08 72 1b 4c 8b 06 4c 8b 4c 16 f8 4c 89 07 4c 89 4c 17 f8 c3 66 2e 0f 1f 84 00 00 00 00 00 83 fa 04 72 1b <8b> 0e 44 8b 44 16 fc 89 0f 44 89 44 17 fc c3 66 66 66 2e 0f 1f All code ======== 0: 89 5c 17 f8 mov %ebx,-0x8(%rdi,%rdx,1) 4: c3 retq 5: 90 nop 6: 83 fa 08 cmp $0x8,%edx 9: 72 1b jb 0x26 b: 4c 8b 06 mov (%rsi),%r8 e: 4c 8b 4c 16 f8 mov -0x8(%rsi,%rdx,1),%r9 13: 4c 89 07 mov %r8,(%rdi) 16: 4c 89 4c 17 f8 mov %r9,-0x8(%rdi,%rdx,1) 1b: c3 retq 1c: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 23: 00 00 00 26: 83 fa 04 cmp $0x4,%edx 29: 72 1b jb 0x46 2b:* 8b 0e mov (%rsi),%ecx <-- trapping instruction 2d: 44 8b 44 16 fc mov -0x4(%rsi,%rdx,1),%r8d 32: 89 0f mov %ecx,(%rdi) 34: 44 89 44 17 fc mov %r8d,-0x4(%rdi,%rdx,1) 39: c3 retq 3a: 66 66 66 2e 0f 1f 00 data32 data32 nopw %cs:(%rax) Code starting with the faulting instruction =========================================== 0: 8b 0e mov (%rsi),%ecx 2: 44 8b 44 16 fc mov -0x4(%rsi,%rdx,1),%r8d 7: 89 0f mov %ecx,(%rdi) 9: 44 89 44 17 fc mov %r8d,-0x4(%rdi,%rdx,1) e: c3 retq f: 66 66 66 2e 0f 1f 00 data32 data32 nopw %cs:(%rax) [ 2435.094918] RIP memcpy (arch/x86/lib/memcpy_64.S:160) [ 2435.094918] RSP <ffff88021a9cb4d0> [ 2435.094918] CR2: ffff88056730bfd4 Thanks, Sasha -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html