Index: include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h =================================================================== --- include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h +++ include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h @@ -287,7 +287,10 @@ bool MarkAsSink, ExplodedNode *P = nullptr, const ProgramPointTag *Tag = nullptr) { - if (!State || (State == Pred->getState() && !Tag && !MarkAsSink)) + // It may not be safe to use the "Pred" node with no tag because the "Pred" + // node may be recycled in the reclamation function. + if (!State || (State == Pred->getState() && !Tag && !MarkAsSink && + Pred->getLocation().getTag())) return Pred; Changed = true; Index: test/Analysis/PR24184.cpp =================================================================== --- /dev/null +++ test/Analysis/PR24184.cpp @@ -0,0 +1,97 @@ +// RUN: %clang_cc1 -w -analyze -analyzer-eagerly-assume -fcxx-exceptions -analyzer-checker=core -analyzer-checker=alpha.core.PointerArithm,alpha.core.CastToStruct -analyzer-max-loop 64 -verify %s +// RUN: %clang_cc1 -w -analyze -analyzer-checker=core -analyzer-checker=cplusplus -fcxx-exceptions -analyzer-checker alpha.core.PointerArithm,alpha.core.CastToStruct -analyzer-max-loop 63 -verify %s + +// These tests used to hit an assertion in the bug report. Test case from http://llvm.org/PR24184. +typedef struct { + int cbData; + unsigned pbData; +} CRYPT_DATA_BLOB; + +typedef enum { DT_NONCE_FIXED } DATA_TYPE; +int a; +typedef int *vcreate_t(int *, DATA_TYPE, int, int); +void fn1(unsigned, unsigned) { + char b = 0; + for (; 1; a++, &b + a * 0) // expected-warning{{Pointer arithmetic done on non-array variables means reliance on memory layout, which is dangerous}} + ; +} + +vcreate_t fn2; +struct A { + CRYPT_DATA_BLOB value; + int m_fn1() { + int c; + value.pbData == 0; + fn1(0, 0); + } +}; +struct B { + A IkeHashAlg; + A IkeGType; + A NoncePhase1_r; +}; +class C { + int m_fn2(B *); + void m_fn3(B *, int, int, int); +}; +int C::m_fn2(B *p1) { + int *d; + int e = p1->IkeHashAlg.m_fn1(); + unsigned f = p1->IkeGType.m_fn1(), h; + int g; + d = fn2(0, DT_NONCE_FIXED, (char)0, p1->NoncePhase1_r.value.cbData); + h = 0 | 0; + m_fn3(p1, 0, 0, 0); +} + +// case 2: +typedef struct { + int cbData; + unsigned char *pbData; +} CRYPT_DATA_BLOB_1; +typedef unsigned uint32_t; +void fn1_1(void *p1, const void *p2) { p1 != p2; } + +void fn2_1(uint32_t *p1, unsigned char *p2, uint32_t p3) { + unsigned i = 0; + for (0; i < p3; i++) + fn1_1(p1 + i, p2 + i * 0); // expected-warning{{Pointer arithmetic done on non-array variables means reliance on memory layout, which is dangerous}} +} + +struct A_1 { + CRYPT_DATA_BLOB_1 value; + uint32_t m_fn1() { + uint32_t a; + if (value.pbData) + fn2_1(&a, value.pbData, value.cbData); + return 0; + } +}; +struct { + A_1 HashAlgId; +} *b; +void fn3() { + uint32_t c, d; + d = b->HashAlgId.m_fn1(); + d << 0 | 0 | 0; + c = 0; + 0 | 1 << 0 | 0 && b; +} + +// case 3: +struct ST { + char c; +}; +char *p; +int foo1(ST); +int foo2() { + ST *p1 = (ST *)(p); // expected-warning{{Casting a non-structure type to a structure type and accessing a field can lead to memory access errors or data corruption}} + while (p1->c & 0x0F || p1->c & 0x07) + p1 = p1 + foo1(*p1); +} + +int foo3(int *node) { + int i = foo2(); + if (i) + return foo2(); +} \ No newline at end of file Index: test/Analysis/malloc.c =================================================================== --- test/Analysis/malloc.c +++ test/Analysis/malloc.c @@ -1386,7 +1386,8 @@ int *s; char *b = realloc(a->p, size); char *m = realloc(a->p, size); // expected-warning {{Attempt to free released memory}} - return a->p; + //PR24184: Object "a->p" is returned after being freed by calling "realloc". + return a->p; // expected-warning {{Use of memory after it is freed}} } // We should not warn in this case since the caller will presumably free a->p in all cases.