Re: WARNING in bpf_raw_tp_link_fill_link_info
On Fri, Sep 11, 2020 at 12:01 AM Andrii Nakryiko
wrote:
>
> On Thu, Sep 10, 2020 at 2:31 AM syzbot
> wrote:
> >
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit:7fb5eefd selftests/bpf: Fix test_sysctl_loop{1, 2} failure..
> > git tree: bpf-next
> > console output: https://syzkaller.appspot.com/x/log.txt?x=1424fdb390
> > kernel config: https://syzkaller.appspot.com/x/.config?x=b6856d16f78d8fa9
> > dashboard link: https://syzkaller.appspot.com/bug?extid=976d5ecfab0c7eb43ac3
> > compiler: gcc (GCC) 10.1.0-syz 20200507
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14a1f41190
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10929c1190
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+976d5ecfab0c7eb43...@syzkaller.appspotmail.com
> >
> > [ cut here ]
> > WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150
> > check_copy_size include/linux/thread_info.h:150 [inline]
> > WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150 copy_to_user
> > include/linux/uaccess.h:167 [inline]
> > WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150
> > bpf_raw_tp_link_fill_link_info+0x306/0x350 kernel/bpf/syscall.c:2661
> > Kernel panic - not syncing: panic_on_warn set ...
> > CPU: 0 PID: 6854 Comm: syz-executor574 Not tainted 5.9.0-rc1-syzkaller #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> > Google 01/01/2011
> > Call Trace:
> > __dump_stack lib/dump_stack.c:77 [inline]
> > dump_stack+0x18f/0x20d lib/dump_stack.c:118
> > panic+0x2e3/0x75c kernel/panic.c:231
> > __warn.cold+0x20/0x4a kernel/panic.c:600
> > report_bug+0x1bd/0x210 lib/bug.c:198
> > handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
> > exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
> > asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
> > RIP: 0010:check_copy_size include/linux/thread_info.h:150 [inline]
> > RIP: 0010:copy_to_user include/linux/uaccess.h:167 [inline]
> > RIP: 0010:bpf_raw_tp_link_fill_link_info+0x306/0x350
> > kernel/bpf/syscall.c:2661
> > Code: 41 bc ea ff ff ff e9 35 ff ff ff 4c 89 ff e8 41 66 33 00 e9 d0 fd ff
> > ff 4c 89 ff e8 a4 66 33 00 e9 06 ff ff ff e8 ca ed f2 ff <0f> 0b eb 94 48
> > 89 ef e8 2e 66 33 00 e9 65 fd ff ff e8 24 66 33 00
> > RSP: 0018:c900051c7bd0 EFLAGS: 00010293
> > RAX: RBX: c900051c7c60 RCX: 818179d6
> > RDX: 88808b49 RSI: 81817a96 RDI: 0006
> > RBP: 0019 R08: R09: c900051c7c7f
> > R10: R11: R12: 0019
> > R13: 1265 R14: 8986ecc0 R15: c900051c7c78
> > bpf_link_get_info_by_fd kernel/bpf/syscall.c:3626 [inline]
> > bpf_obj_get_info_by_fd+0x43a/0xc40 kernel/bpf/syscall.c:3664
> > __do_sys_bpf+0x1906/0x4b30 kernel/bpf/syscall.c:4237
> > do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
> > entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > RIP: 0033:0x4405f9
> > Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
> > RSP: 002b:7fff47155808 EFLAGS: 0246 ORIG_RAX: 0141
> > RAX: ffda RBX: 004002c8 RCX: 004405f9
> > RDX: 0010 RSI: 20c0 RDI: 000f
> > RBP: 006ca018 R08: 004002c8 R09: 004002c8
> > R10: 004002c8 R11: 0246 R12: 00401e00
> > R13: 00401e90 R14: R15:
> > Kernel Offset: disabled
> > Rebooting in 86400 seconds..
> >
>
> #syz fix: b474959d5afd ("bpf: Fix a buffer out-of-bound access when
> filling raw_tp link_info")
Complete patch title:
#syz fix:
bpf: Fix a buffer out-of-bound access when filling raw_tp link_info
Re: WARNING in bpf_raw_tp_link_fill_link_info
On Thu, Sep 10, 2020 at 2:31 AM syzbot
wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:7fb5eefd selftests/bpf: Fix test_sysctl_loop{1, 2} failure..
> git tree: bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=1424fdb390
> kernel config: https://syzkaller.appspot.com/x/.config?x=b6856d16f78d8fa9
> dashboard link: https://syzkaller.appspot.com/bug?extid=976d5ecfab0c7eb43ac3
> compiler: gcc (GCC) 10.1.0-syz 20200507
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14a1f41190
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10929c1190
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+976d5ecfab0c7eb43...@syzkaller.appspotmail.com
>
> [ cut here ]
> WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150 check_copy_size
> include/linux/thread_info.h:150 [inline]
> WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150 copy_to_user
> include/linux/uaccess.h:167 [inline]
> WARNING: CPU: 0 PID: 6854 at include/linux/thread_info.h:150
> bpf_raw_tp_link_fill_link_info+0x306/0x350 kernel/bpf/syscall.c:2661
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 0 PID: 6854 Comm: syz-executor574 Not tainted 5.9.0-rc1-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0x18f/0x20d lib/dump_stack.c:118
> panic+0x2e3/0x75c kernel/panic.c:231
> __warn.cold+0x20/0x4a kernel/panic.c:600
> report_bug+0x1bd/0x210 lib/bug.c:198
> handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
> exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
> asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
> RIP: 0010:check_copy_size include/linux/thread_info.h:150 [inline]
> RIP: 0010:copy_to_user include/linux/uaccess.h:167 [inline]
> RIP: 0010:bpf_raw_tp_link_fill_link_info+0x306/0x350 kernel/bpf/syscall.c:2661
> Code: 41 bc ea ff ff ff e9 35 ff ff ff 4c 89 ff e8 41 66 33 00 e9 d0 fd ff ff
> 4c 89 ff e8 a4 66 33 00 e9 06 ff ff ff e8 ca ed f2 ff <0f> 0b eb 94 48 89 ef
> e8 2e 66 33 00 e9 65 fd ff ff e8 24 66 33 00
> RSP: 0018:c900051c7bd0 EFLAGS: 00010293
> RAX: RBX: c900051c7c60 RCX: 818179d6
> RDX: 88808b49 RSI: 81817a96 RDI: 0006
> RBP: 0019 R08: R09: c900051c7c7f
> R10: R11: R12: 0019
> R13: 1265 R14: 8986ecc0 R15: c900051c7c78
> bpf_link_get_info_by_fd kernel/bpf/syscall.c:3626 [inline]
> bpf_obj_get_info_by_fd+0x43a/0xc40 kernel/bpf/syscall.c:3664
> __do_sys_bpf+0x1906/0x4b30 kernel/bpf/syscall.c:4237
> do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
> entry_SYSCALL_64_after_hwframe+0x44/0xa9
> RIP: 0033:0x4405f9
> Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f
> 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:7fff47155808 EFLAGS: 0246 ORIG_RAX: 0141
> RAX: ffda RBX: 004002c8 RCX: 004405f9
> RDX: 0010 RSI: 20c0 RDI: 000f
> RBP: 006ca018 R08: 004002c8 R09: 004002c8
> R10: 004002c8 R11: 0246 R12: 00401e00
> R13: 00401e90 R14: R15:
> Kernel Offset: disabled
> Rebooting in 86400 seconds..
>
#syz fix: b474959d5afd ("bpf: Fix a buffer out-of-bound access when
filling raw_tp link_info")
>
> ---
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>
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