Commit cbddd61d authored by Jakob Gruber's avatar Jakob Gruber Committed by V8 LUCI CQ

[regexp] Periodically check for stack overflow during node generation

Recursive ToNode node generation may overflow the stack for large
graphs. As a quick fix, insert periodic stack overflow checks in
selected ToNode methods.

As a more permanent fix, in the future we could abort gracefully
(instead of crashing on a CHECK), and/or refactor into iterative node
generation.

Bug: v8:12472
Change-Id: Ie5fbe838c5f6a5192d7d9b44bfe6f6c76a8d26e7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3398112Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78667}
parent c992a256
......@@ -778,6 +778,8 @@ void RegExpDisjunction::FixSingleCharacterDisjunctions(
RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
compiler->ToNodeMaybeCheckForStackOverflow();
ZoneList<RegExpTree*>* alternatives = this->alternatives();
if (alternatives->length() > 2) {
......@@ -1089,6 +1091,8 @@ class AssertionSequenceRewriter final {
RegExpNode* RegExpAlternative::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
compiler->ToNodeMaybeCheckForStackOverflow();
ZoneList<RegExpTree*>* children = nodes();
AssertionSequenceRewriter::MaybeRewrite(children, compiler->zone());
......
......@@ -3950,5 +3950,9 @@ RegExpNode* RegExpCompiler::PreprocessRegExp(RegExpCompileData* data,
return node;
}
void RegExpCompiler::ToNodeCheckForStackOverflow() {
CHECK(!StackLimitCheck{isolate()}.HasOverflowed());
}
} // namespace internal
} // namespace v8
......@@ -550,6 +550,18 @@ class RegExpCompiler {
current_expansion_factor_ = value;
}
// The recursive nature of ToNode node generation means we may run into stack
// overflow issues. We introduce periodic checks to detect these, and the
// tick counter helps limit overhead of these checks.
// TODO(jgruber): This is super hacky and should be replaced by an abort
// mechanism or iterative node generation.
void ToNodeMaybeCheckForStackOverflow() {
if ((to_node_overflow_check_ticks_++ % 16 == 0)) {
ToNodeCheckForStackOverflow();
}
}
void ToNodeCheckForStackOverflow();
Isolate* isolate() const { return isolate_; }
Zone* zone() const { return zone_; }
......@@ -567,6 +579,7 @@ class RegExpCompiler {
bool one_byte_;
bool reg_exp_too_big_;
bool limiting_recursion_;
int to_node_overflow_check_ticks_ = 0;
bool optimize_;
bool read_backward_;
int current_expansion_factor_;
......
......@@ -180,6 +180,9 @@
# https://crbug.com/v8/10948
'wasm/atomics': [PASS, ['arch == arm and not simulator_run', SKIP]],
# crbug.com/v8/12472 Stack overflow during regexp node generation.
'regress/regress-crbug-595657': [SKIP],
##############################################################################
# Tests where variants make no sense.
'd8/enable-tracing': [PASS, NO_VARIANTS],
......
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