Commit Graph

2 Commits

Author SHA1 Message Date
Ethan Nicholas
cb13c892af Added range highlighting to SkSL error reports
SkSL errors now identify the specific range of code they are describing,
rather than just the line number.

Change-Id: Ifabb3148476f9b4cd8e532f23e5b38e1cf33a87e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/528039
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
2022-04-07 13:29:48 +00:00
John Stiles
683ae40560 Fix for fuzzer-discovered error with deeply-nested expressions.
The fuzzer constructs a long, valid nonsense expression
(x+x+x-x+x-x, etc.) which exceeds parse depth. At that point, the token
stream points to a `+` token. The parser attempts to consume a new
statement but stops in `unaryExpression`; this fails again, due to the
max parse-depth, but doesn't consume a token. The parser continues
trying to parse the statement, but stopping in `unaryExpression`, making
no forward progress in an infinite loop.

I've made a couple of changes as a result.
- Exceeding the max parse depth now sets `fEncounteredFatalError`.
- Encountering a fatal error causes block() to immediately halt. This
  actually undoes a few of the arbitrary changes from
  http://review.skia.org/506463 but not in a bad way.
- `unaryExpression()` now consumes a token before checking parse-depth.
- `structDeclaration()` had a similar issue where it could potentially
  fail without consuming any tokens; this is fixed as well.
- Some unnecessarily-nested logic in ternaryExpression() was flattened
  while I tried to ensure that it always consumes a token.

Change-Id: I52c2161965ffbcef1185761ca6897ec1cba5df89
Bug: oss-fuzz:44551
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/507436
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
2022-02-11 14:25:34 +00:00