The issue is that common_setup() wasn't called by the fuzz target,
leaving secp256k1_ctx as NULL.
UBSan error:
$ UBSAN_OPTIONS="print_stacktrace=1:halt_on_error=1" \
./fuzz-channel_id crash-1575b41ef09e62e4c09c165e6dc037a110b113f2
INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 1153355603
INFO: Loaded 1 modules (25915 inline 8-bit counters): 25915 [0x563bae7ac3a8, 0x563bae7b28e3),
INFO: Loaded 1 PC tables (25915 PCs): 25915 [0x563bae7b28e8,0x563bae817c98),
./fuzz-channel_id: Running 1 inputs 1 time(s) each.
Running: crash-1575b41ef09e62e4c09c165e6dc037a110b113f2
bitcoin/pubkey.c:22:33: runtime error: null pointer passed as argument 1, which is declared to never be null
external/libwally-core/src/secp256k1/include/secp256k1.h:373:3: note: nonnull attribute specified here
#0 0x563bae41e3db in pubkey_from_der bitcoin/pubkey.c:19:7
#1 0x563bae4205e0 in fromwire_pubkey bitcoin/pubkey.c:111:7
#2 0x563bae46437c in run tests/fuzz/fuzz-channel_id.c:42:3
#3 0x563bae2f6016 in LLVMFuzzerTestOneInput tests/fuzz/libfuzz.c:23:2
#4 0x563bae20a450 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long)
#5 0x563bae1f4c3f in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned long)
#6 0x563bae1fa6e6 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long))
#7 0x563bae223052 in main (tests/fuzz/fuzz-channel_id+0x181052) (BuildId: f7f56e14ffc06df54ab732d79ea922e773de1f25)
#8 0x7fa7fa113082 in __libc_start_main
#9 0x563bae1efbdd in _start
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior bitcoin/pubkey.c:22:33 in
Before:
Ten builds, laptop -j5, no ccache:
```
real 0m36.686000-38.956000(38.608+/-0.65)s
user 2m32.864000-42.253000(40.7545+/-2.7)s
sys 0m16.618000-18.316000(17.8531+/-0.48)s
```
Ten builds, laptop -j5, ccache (warm):
```
real 0m8.212000-8.577000(8.39989+/-0.13)s
user 0m12.731000-13.212000(12.9751+/-0.17)s
sys 0m3.697000-3.902000(3.83722+/-0.064)s
```
After:
Ten builds, laptop -j5, no ccache: 8% faster
```
real 0m33.802000-35.773000(35.468+/-0.54)s
user 2m19.073000-27.754000(26.2542+/-2.3)s
sys 0m15.784000-17.173000(16.7165+/-0.37)s
```
Ten builds, laptop -j5, ccache (warm): 1% faster
```
real 0m8.200000-8.485000(8.30138+/-0.097)s
user 0m12.485000-13.100000(12.7344+/-0.19)s
sys 0m3.702000-3.889000(3.78787+/-0.056)s
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We should actually be including this (as it may define _GNU_SOURCE
etc) before any system headers. But where we include <assert.h> we
often didn't, because check-includes would complain that the headers
included it too.
Weaken that check, and include config.h in C files before assert.h.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>