pkg/report: improve report titles

1. Replace stacktraceRe with custom code which is more flexible.
stacktraceRe stumbled on any unrelated lines and
could not properly parse truncated stacks.

2. Match report regexp earlier.
If we match simler title regexp, but don't match
report regexp or fail to parse stack trace, the report is corrupted.
This eliminates lots of duplicate corrupted oops entries,
which were there only because we had complex regexp's in titles.

3. Ignore low-level frames during stack parsing.
E.g. we never want to report a GPF in lock_acquire or memcpy
(somewhat similar to what we do for guilty files).

4. Add a bunch of specialized formats for WARNINGs.
There is number of generic debugging facilities (like ODEBUG,
debug usercopy, kobject, refcount_t, etc), and the bug
is never in these facilities, it's in the caller instead.

5. Improve some other oops formats.

6. Add a bunch of additional tests.

This resolves most of TODOs in tests.
Fixes #515

1 files changed, 51 insertions, 0 deletions

diff --git a/pkg/report/testdata/linux/guilty/30 b/pkg/report/testdata/linux/guilty/30
new file mode 100644
index 000000000..fb4b044f6
--- /dev/null
+++ b/pkg/report/testdata/linux/guilty/30
@@ -0,0 +1,51 @@
+FILE: net/ipv4/netfilter/ipt_CLUSTERIP.c
+
+------------[ cut here ]------------
+proc_dir_entry 'ipt_CLUSTERIP/172.20.0.170' already registered
+WARNING: CPU: 1 PID: 4074 at fs/proc/generic.c:330 proc_register+0x2a4/0x370 fs/proc/generic.c:329
+Kernel panic - not syncing: panic_on_warn set ...
+
+CPU: 1 PID: 4074 Comm: syzkaller105937 Not tainted 4.15.0+ #221
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+Call Trace:
+ __dump_stack lib/dump_stack.c:17 [inline]
+ dump_stack+0x194/0x257 lib/dump_stack.c:53
+ panic+0x1e4/0x41c kernel/panic.c:183
+ __warn+0x1dc/0x200 kernel/panic.c:547
+ report_bug+0x211/0x2d0 lib/bug.c:184
+ fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
+ fixup_bug arch/x86/kernel/traps.c:247 [inline]
+ do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
+ do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
+ invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1097
+RIP: 0010:proc_register+0x2a4/0x370 fs/proc/generic.c:329
+RSP: 0018:ffff8801da886e20 EFLAGS: 00010286
+RAX: dffffc0000000008 RBX: ffff8801d21cc7b8 RCX: ffffffff815a57ae
+RDX: 0000000000000000 RSI: 1ffff1003b510d74 RDI: 1ffff1003b510d49
+RBP: ffff8801da886e70 R08: 1ffff1003b510d0b R09: 0000000000000000
+R10: ffff8801da886cd8 R11: 0000000000000000 R12: ffff8801cbf66440
+R13: dffffc0000000000 R14: ffff8801ca2fa348 R15: ffff8801cbf66501
+ proc_create_data+0xf8/0x180 fs/proc/generic.c:494
+ clusterip_config_init net/ipv4/netfilter/ipt_CLUSTERIP.c:250 [inline]
+ clusterip_tg_check+0xf9c/0x16d0 net/ipv4/netfilter/ipt_CLUSTERIP.c:488
+ xt_check_target+0x22c/0x7d0 net/netfilter/x_tables.c:850
+ check_target net/ipv4/netfilter/ip_tables.c:513 [inline]
+ find_check_entry.isra.8+0x8c8/0xcb0 net/ipv4/netfilter/ip_tables.c:554
+ translate_table+0xed1/0x1610 net/ipv4/netfilter/ip_tables.c:725
+ do_replace net/ipv4/netfilter/ip_tables.c:1141 [inline]
+ do_ipt_set_ctl+0x370/0x5f0 net/ipv4/netfilter/ip_tables.c:1675
+ nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
+ nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
+ ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1259
+ sctp_setsockopt+0x2b6/0x61d0 net/sctp/socket.c:4104
+ sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975
+ SYSC_setsockopt net/socket.c:1849 [inline]
+ SyS_setsockopt+0x189/0x360 net/socket.c:1828
+ entry_SYSCALL_64_fastpath+0x29/0xa0
+RIP: 0033:0x44afa9
+RSP: 002b:00007f43f70edce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
+RAX: ffffffffffffffda RBX: 00000000006e0c3c RCX: 000000000044afa9
+RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000004
+RBP: 00000000006e0c38 R08: 0000000000000348 R09: 0000000000000000
+R10: 0000000020013c90 R11: 0000000000000246 R12: 0000000000000000
+R13: 00007ffe194fe84f R14: 00007f43f70ee9c0 R15: 0000000000000005