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1 Commits

Author SHA1 Message Date
John Stiles
a695d62772 Limit struct nesting depth to a maximum of eight levels.
This addresses a sanitizer issue discovered in
https://oss-fuzz.com/testcase-detail/4908118777266176 (it has not been
assigned an oss-fuzz bug number yet; coming soon)

This puts an upper bound on struct nesting, again to prevent memory-
layout and other recursive type-handling code from overflowing the
stack. Coincidentally, while researching GLSL behavior around this bug,
I learned that WebGL has a similar limitation but caps nested structs to
4 deep. (I could not find any documented GLSL upper bound.)

Note that both the GLSL and Metal outputs for StructMaxDepth are badly
malformed. (Structs cannot be embedded within another struct in GLSL;
structs SA7 and below are never declared in GLSL; the array list for SA7
is backwards in GLSL; Metal is missing structs SA1 through SA8; Metal
puts the array list on the type instead of the variable name.)
These issues will be addressed in separate CLs.

Change-Id: I0f1059b6faa400cd0647dd7010ec839f73779a36
Bug: skia:10922, skia:10923, skia:10925, skia:10926
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/333316
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
2020-11-10 16:58:37 +00:00