[analyzer] Fix nullptr dereference for symbols from pointer invalidation #106568
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As reported in llvm#105648 (comment) commit 08ad8dc7154bf3ab79f750e6d5fb7df597c7601a introduced a nullptr dereference in the case when store contains a binding to a symbol that has no origin region associated with it, such as the symbol generated when a pointer is passed to an opaque function.
llvmbot
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clang
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@llvm/pr-subscribers-clang-static-analyzer-1 @llvm/pr-subscribers-clang Author: Arseniy Zaostrovnykh (necto) ChangesAs reported in #105648 (comment) commit 08ad8dc7154bf3ab79f750e6d5fb7df597c7601a Full diff: https://github.com/llvm/llvm-project/pull/106568.diff 2 Files Affected:
diff --git a/clang/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
index 20232405d572d2..d3b185541729d3 100644
--- a/clang/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
@@ -308,7 +308,10 @@ static const MemSpaceRegion *getStackOrGlobalSpaceRegion(const MemRegion *R) {
const MemRegion *getOriginBaseRegion(const MemRegion *Reg) {
Reg = Reg->getBaseRegion();
while (const auto *SymReg = dyn_cast<SymbolicRegion>(Reg)) {
- Reg = SymReg->getSymbol()->getOriginRegion()->getBaseRegion();
+ const auto* OriginReg = SymReg->getSymbol()->getOriginRegion();
+ if (!OriginReg)
+ break;
+ Reg = OriginReg->getBaseRegion();
}
return Reg;
}
diff --git a/clang/test/Analysis/stack-addr-ps.c b/clang/test/Analysis/stack-addr-ps.c
index 138b8c16b02bde..f47529623a6f57 100644
--- a/clang/test/Analysis/stack-addr-ps.c
+++ b/clang/test/Analysis/stack-addr-ps.c
@@ -126,3 +126,22 @@ void caller_for_nested_leaking() {
int *ptr = 0;
caller_mid_for_nested_leaking(&ptr);
}
+
+// This used to crash StackAddrEscapeChecker because
+// it features a symbol conj_$1{struct c *, LC1, S763, #1}
+// that has no origin region.
+// bbi-98571
+struct a {
+ int member;
+};
+
+struct c {
+ struct a *nested_ptr;
+};
+long global_var;
+void opaque(struct c*);
+void bbi_98571_no_crash() {
+ struct c *ptr = (struct c *)global_var;
+ opaque(ptr);
+ ptr->nested_ptr->member++;
+}
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✅ With the latest revision this PR passed the C/C++ code formatter. |
steakhal
requested changes
Aug 29, 2024
steakhal
approved these changes
Aug 29, 2024
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/30/builds/5072 Here is the relevant piece of the build log for the reference |
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As reported in #105648 (comment) commit 08ad8dc7154bf3ab79f750e6d5fb7df597c7601a
introduced a nullptr dereference in the case when store contains a binding to a symbol that has no origin region associated with it, such as the symbol generated when a pointer is passed to an opaque function.