// RUN: %clang_analyze_cc1 -verify \ // RUN: -Wno-alloc-size \ // RUN: -analyzer-checker=core \ // RUN: -analyzer-checker=alpha.deadcode.UnreachableCode \ // RUN: -analyzer-checker=unix.Malloc \ // RUN: -analyzer-checker=debug.ExprInspection \ // RUN: -analyzer-config unix.DynamicMemoryModeling:Optimistic=true %s typedef __typeof(sizeof(int)) size_t; void *malloc(size_t); void free(void *); void *realloc(void *ptr, size_t size); void *calloc(size_t nmemb, size_t size); void __attribute((ownership_returns(malloc))) *my_malloc(size_t); void __attribute((ownership_takes(malloc, 1))) my_free(void *); void my_freeBoth(void *, void *) __attribute((ownership_holds(malloc, 1, 2))); void __attribute((ownership_returns(malloc, 1))) *my_malloc2(size_t); void __attribute((ownership_holds(malloc, 1))) my_hold(void *); // Duplicate attributes are silly, but not an error. // Duplicate attribute has no extra effect. // If two are of different kinds, that is an error and reported as such. void __attribute((ownership_holds(malloc, 1))) __attribute((ownership_holds(malloc, 1))) __attribute((ownership_holds(malloc, 3))) my_hold2(void *, void *, void *); __attribute((ownership_returns(user_malloc, 1))) void *user_malloc(size_t); __attribute((ownership_takes(user_malloc, 1))) void user_free(void *); void clang_analyzer_dump(int); void *my_malloc3(size_t); void *myglobalpointer; struct stuff { void *somefield; }; struct stuff myglobalstuff; void f1(void) { int *p = malloc(12); return; // expected-warning{{Potential leak of memory pointed to by}} } void f2(void) { int *p = malloc(12); free(p); free(p); // expected-warning{{Attempt to release already released memory}} } void f2_realloc_0(void) { int *p = malloc(12); realloc(p,0); realloc(p,0); // expected-warning{{Attempt to release already released memory}} } void f2_realloc_1(void) { int *p = malloc(12); int *q = realloc(p,0); // no-warning } // ownership attributes tests void naf1(void) { int *p = my_malloc3(12); return; // no-warning } void n2af1(void) { int *p = my_malloc2(12); return; // expected-warning{{Potential leak of memory pointed to by}} } void af1(void) { int *p = my_malloc(12); return; // expected-warning{{Potential leak of memory pointed to by}} } void af1_b(void) { int *p = my_malloc(12); } // expected-warning{{Potential leak of memory pointed to by}} void af1_c(void) { myglobalpointer = my_malloc(12); // no-warning } void af1_d(void) { struct stuff mystuff; mystuff.somefield = my_malloc(12); } // expected-warning{{Potential leak of memory pointed to by}} // Test that we can pass out allocated memory via pointer-to-pointer. void af1_e(void **pp) { *pp = my_malloc(42); // no-warning } void af1_f(struct stuff *somestuff) { somestuff->somefield = my_malloc(12); // no-warning } // Allocating memory for a field via multiple indirections to our arguments is OK. void af1_g(struct stuff **pps) { *pps = my_malloc(sizeof(struct stuff)); // no-warning (*pps)->somefield = my_malloc(42); // no-warning } void af2(void) { int *p = my_malloc(12); my_free(p); free(p); // expected-warning{{Attempt to release already released memory}} } void af2b(void) { int *p = my_malloc(12); free(p); my_free(p); // expected-warning{{Attempt to release already released memory}} } void af2c(void) { int *p = my_malloc(12); free(p); my_hold(p); // expected-warning{{Attempt to release already released memory}} } void af2d(void) { int *p = my_malloc(12); free(p); my_hold2(0, 0, p); // expected-warning{{Attempt to release already released memory}} } // No leak if malloc returns null. void af2e(void) { int *p = my_malloc(12); if (!p) return; // no-warning free(p); // no-warning } // This case inflicts a possible double-free. void af3(void) { int *p = my_malloc(12); my_hold(p); free(p); // expected-warning{{Attempt to release non-owned memory}} } int * af4(void) { int *p = my_malloc(12); my_free(p); return p; // expected-warning{{Use of memory after it is released}} } // This case is (possibly) ok, be conservative int * af5(void) { int *p = my_malloc(12); my_hold(p); return p; // no-warning } // This case tests that storing malloc'ed memory to a static variable which is // then returned is not leaked. In the absence of known contracts for functions // or inter-procedural analysis, this is a conservative answer. int *f3(void) { static int *p = 0; p = malloc(12); return p; // no-warning } // This case tests that storing malloc'ed memory to a static global variable // which is then returned is not leaked. In the absence of known contracts for // functions or inter-procedural analysis, this is a conservative answer. static int *p_f4 = 0; int *f4(void) { p_f4 = malloc(12); return p_f4; // no-warning } int *f5(void) { int *q = malloc(12); q = realloc(q, 20); return q; // no-warning } void f6(void) { int *p = malloc(12); if (!p) return; // no-warning else free(p); } void f6_realloc(void) { int *p = malloc(12); if (!p) return; // no-warning else realloc(p,0); } char *doit2(void); void pr6069(void) { char *buf = doit2(); free(buf); } void pr6293(void) { free(0); } void f7(void) { char *x = (char*) malloc(4); free(x); x[0] = 'a'; // expected-warning{{Use of memory after it is released}} } void f7_realloc(void) { char *x = (char*) malloc(4); realloc(x,0); x[0] = 'a'; // expected-warning{{Use of memory after it is released}} } void mallocCastToVoid(void) { void *p = malloc(2); const void *cp = p; // not crash free(p); } void mallocCastToFP(void) { void *p = malloc(2); void (*fp)(void) = p; // not crash free(p); } // This tests that malloc() buffers are undefined by default char mallocGarbage (void) { char *buf = malloc(2); char result = buf[1]; // expected-warning{{uninitialized}} free(buf); return result; } // This tests that calloc() buffers need to be freed void callocNoFree (void) { char *buf = calloc(2,2); return; // expected-warning{{Potential leak of memory pointed to by}} } // These test that calloc() buffers are zeroed by default char callocZeroesGood (void) { char *buf = calloc(2,2); char result = buf[3]; // no-warning if (buf[1] == 0) { free(buf); } return result; // no-warning } char callocZeroesBad (void) { char *buf = calloc(2,2); char result = buf[3]; // no-warning if (buf[1] != 0) { free(buf); // expected-warning{{never executed}} } return result; // expected-warning{{Potential leak of memory pointed to by}} } void testMultipleFreeAnnotations(void) { int *p = malloc(12); int *q = malloc(12); my_freeBoth(p, q); } void testNoUninitAttr(void) { int *p = user_malloc(sizeof(int)); int read = p[0]; // no-warning clang_analyzer_dump(p[0]); // expected-warning{{Unknown}} user_free(p); } // Regression test for GH#183344 — crash when a function has both // ownership_returns and ownership_takes attributes. typedef struct GH183344_X GH183344_X; typedef struct GH183344_Y GH183344_Y; GH183344_Y *GH183344_X_to_Y(GH183344_X *x) __attribute__((ownership_returns(GH183344_Y))) __attribute__((ownership_takes(GH183344_X, 1))); void testGH183344(void) { GH183344_Y *y = GH183344_X_to_Y(0); // no-crash (void)y; } // expected-warning{{Potential leak of memory pointed to by 'y'}} // Extended regression tests for GH#183344 — additional combinations of // ownership_returns, ownership_takes, and ownership_holds. GH183344_X *GH183344_alloc_X(void) __attribute__((ownership_returns(GH183344_X))); void GH183344_free_X(GH183344_X *) __attribute__((ownership_takes(GH183344_X, 1))); void GH183344_free_Y(GH183344_Y *) __attribute__((ownership_takes(GH183344_Y, 1))); // Returns + Holds variant: Y is allocated, X is held (not consumed) by callee. GH183344_Y *GH183344_X_to_Y_hold(GH183344_X *x) __attribute__((ownership_returns(GH183344_Y))) __attribute__((ownership_holds(GH183344_X, 1))); // Returns + two Takes (same pool): both X arguments are consumed, Y is // returned. Multiple arg indices in one attribute (same pool) is valid; // two ownership_takes attributes with *different* pool names are not. GH183344_Y *GH183344_combine_XX(GH183344_X *x1, GH183344_X *x2) __attribute__((ownership_returns(GH183344_Y))) __attribute__((ownership_takes(GH183344_X, 1, 2))); // No-crash for Returns+Holds with null input — same crash pattern as the // original GH183344 bug but with ownership_holds instead of ownership_takes. void testGH183344_ReturnsHolds_NullInput(void) { GH183344_Y *y = GH183344_X_to_Y_hold(0); // no-crash (void)y; } // expected-warning{{Potential leak of memory pointed to by 'y'}} // Returns+Takes: allocate X, convert to Y (X consumed), free Y — no warnings. void testGH183344_ReturnsTakes_CleanUse(void) { GH183344_X *x = GH183344_alloc_X(); GH183344_Y *y = GH183344_X_to_Y(x); GH183344_free_Y(y); } // no-warning // Returns+Takes: after the conversion X is consumed; freeing it again is a // double-free. void testGH183344_ReturnsTakes_DoubleFreeInput(void) { GH183344_X *x = GH183344_alloc_X(); GH183344_Y *y = GH183344_X_to_Y(x); GH183344_free_X(x); // expected-warning{{Attempt to release already released memory}} GH183344_free_Y(y); } // Returns+Takes: X is consumed but Y is never freed — leak on Y. void testGH183344_ReturnsTakes_LeakRetval(void) { GH183344_X *x = GH183344_alloc_X(); GH183344_Y *y = GH183344_X_to_Y(x); (void)y; } // expected-warning{{Potential leak of memory pointed to by 'y'}} // Returns+Holds: after the hold, X is non-owned by the caller; freeing it // produces a "non-owned memory" warning (analogous to af3). void testGH183344_ReturnsHolds_FreeHeldInput(void) { GH183344_X *x = GH183344_alloc_X(); GH183344_Y *y = GH183344_X_to_Y_hold(x); GH183344_free_X(x); // expected-warning{{Attempt to release non-owned memory}} GH183344_free_Y(y); } // Multiple Takes (same pool) + Returns: both X inputs are consumed, Y is // returned and freed — no warnings. void testGH183344_CombineXX_CleanUse(void) { GH183344_X *x1 = GH183344_alloc_X(); GH183344_X *x2 = GH183344_alloc_X(); GH183344_Y *y = GH183344_combine_XX(x1, x2); GH183344_free_Y(y); } // no-warning // Multiple Takes (same pool): after the combine, x2 is already consumed; // freeing it again is a double-free. void testGH183344_CombineXX_DoubleFreeSecondInput(void) { GH183344_X *x1 = GH183344_alloc_X(); GH183344_X *x2 = GH183344_alloc_X(); GH183344_Y *y = GH183344_combine_XX(x1, x2); GH183344_free_X(x2); // expected-warning{{Attempt to release already released memory}} GH183344_free_Y(y); }