Messages in this thread | | | Date | Wed, 2 Feb 2022 19:59:13 -0800 | Subject | Re: [syzbot] general protection fault in btf_decl_tag_resolve | From | Yonghong Song <> |
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On 2/2/22 7:36 PM, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: b7892f7d5cb2 tools: Ignore errors from `which' when search.. > git tree: bpf > console output: https://syzkaller.appspot.com/x/log.txt?x=13181634700000 > kernel config: https://syzkaller.appspot.com/x/.config?x=5044676c290190f2 > dashboard link: https://syzkaller.appspot.com/bug?extid=53619be9444215e785ed > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16454914700000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16ceb884700000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+53619be9444215e785ed@syzkaller.appspotmail.com > > general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] > CPU: 0 PID: 3592 Comm: syz-executor914 Not tainted 5.16.0-syzkaller-11424-gb7892f7d5cb2 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > RIP: 0010:btf_type_vlen include/linux/btf.h:231 [inline] > RIP: 0010:btf_decl_tag_resolve+0x83e/0xaa0 kernel/bpf/btf.c:3910 > Code: c1 ea 03 80 3c 02 00 0f 85 90 01 00 00 48 8b 1b e8 b7 c9 e6 ff 48 8d 7b 04 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 2b > RSP: 0018:ffffc90001b1fa00 EFLAGS: 00010247 > RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff81918c09 RDI: 0000000000000004 > RBP: ffff888015c32000 R08: 0000000000000008 R09: 0000000000000008 > R10: ffffffff81918bb1 R11: 0000000000000001 R12: 0000000000000004 > R13: 0000000000000008 R14: 0000000000000000 R15: 0000000000000005 > FS: 00005555556fd300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f98c38b8220 CR3: 0000000019537000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > btf_resolve+0x251/0x1020 kernel/bpf/btf.c:4198 > btf_check_all_types kernel/bpf/btf.c:4239 [inline] > btf_parse_type_sec kernel/bpf/btf.c:4280 [inline] > btf_parse kernel/bpf/btf.c:4513 [inline] > btf_new_fd+0x19fe/0x2370 kernel/bpf/btf.c:6047 > bpf_btf_load kernel/bpf/syscall.c:4039 [inline] > __sys_bpf+0x1cbb/0x5970 kernel/bpf/syscall.c:4679 > __do_sys_bpf kernel/bpf/syscall.c:4738 [inline] > __se_sys_bpf kernel/bpf/syscall.c:4736 [inline] > __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4736 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7fd57f202099 > Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007ffe9e5eb898 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd57f202099 > RDX: 0000000000000020 RSI: 0000000020000000 RDI: 0000000000000012 > RBP: 00007fd57f1c6080 R08: 0000000000000000 R09: 0000000000000000 > R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fd57f1c6110 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > </TASK> > Modules linked in: > ---[ end trace 0000000000000000 ]--- > RIP: 0010:btf_type_vlen include/linux/btf.h:231 [inline] > RIP: 0010:btf_decl_tag_resolve+0x83e/0xaa0 kernel/bpf/btf.c:3910 > Code: c1 ea 03 80 3c 02 00 0f 85 90 01 00 00 48 8b 1b e8 b7 c9 e6 ff 48 8d 7b 04 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 2b > RSP: 0018:ffffc90001b1fa00 EFLAGS: 00010247 > RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff81918c09 RDI: 0000000000000004 > RBP: ffff888015c32000 R08: 0000000000000008 R09: 0000000000000008 > R10: ffffffff81918bb1 R11: 0000000000000001 R12: 0000000000000004 > R13: 0000000000000008 R14: 0000000000000000 R15: 0000000000000005 > FS: 00005555556fd300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000000 CR3: 0000000019537000 CR4: 00000000003506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > ---------------- > Code disassembly (best guess): > 0: c1 ea 03 shr $0x3,%edx > 3: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) > 7: 0f 85 90 01 00 00 jne 0x19d > d: 48 8b 1b mov (%rbx),%rbx > 10: e8 b7 c9 e6 ff callq 0xffe6c9cc > 15: 48 8d 7b 04 lea 0x4(%rbx),%rdi > 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax > 20: fc ff df > 23: 48 89 fa mov %rdi,%rdx > 26: 48 c1 ea 03 shr $0x3,%rdx > * 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction > 2e: 48 89 f8 mov %rdi,%rax > 31: 83 e0 07 and $0x7,%eax > 34: 83 c0 03 add $0x3,%eax > 37: 38 d0 cmp %dl,%al > 39: 7c 08 jl 0x43 > 3b: 84 d2 test %dl,%dl > 3d: 0f .byte 0xf > 3e: 85 2b test %ebp,(%rbx) > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches
Thanks for reporting. I am looking at this now.
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