diff --git a/compiler-rt/lib/lsan/lsan_allocator.cpp b/compiler-rt/lib/lsan/lsan_allocator.cpp
index 493bf5f9efc57..a436d9c07ac6c 100644
--- a/compiler-rt/lib/lsan/lsan_allocator.cpp
+++ b/compiler-rt/lib/lsan/lsan_allocator.cpp
@@ -220,6 +220,10 @@ void lsan_free(void *p) {
   Deallocate(p);
 }
 
+void lsan_free_sized(void *p, uptr) { Deallocate(p); }
+
+void lsan_free_aligned_sized(void *p, uptr, uptr) { Deallocate(p); }
+
 void *lsan_realloc(void *p, uptr size, const StackTrace &stack) {
   return SetErrnoOnNull(Reallocate(stack, p, size, 1));
 }
diff --git a/compiler-rt/lib/lsan/lsan_allocator.h b/compiler-rt/lib/lsan/lsan_allocator.h
index 5eed0cbdb309b..2342f11fb5d0d 100644
--- a/compiler-rt/lib/lsan/lsan_allocator.h
+++ b/compiler-rt/lib/lsan/lsan_allocator.h
@@ -127,6 +127,8 @@ void *lsan_aligned_alloc(uptr alignment, uptr size, const StackTrace &stack);
 void *lsan_memalign(uptr alignment, uptr size, const StackTrace &stack);
 void *lsan_malloc(uptr size, const StackTrace &stack);
 void lsan_free(void *p);
+void lsan_free_sized(void *p, uptr size);
+void lsan_free_aligned_sized(void *p, uptr alignment, uptr size);
 void *lsan_realloc(void *p, uptr size, const StackTrace &stack);
 void *lsan_reallocarray(void *p, uptr nmemb, uptr size,
                         const StackTrace &stack);
diff --git a/compiler-rt/lib/lsan/lsan_interceptors.cpp b/compiler-rt/lib/lsan/lsan_interceptors.cpp
index a8252cddacf25..6da9d0d9d24f8 100644
--- a/compiler-rt/lib/lsan/lsan_interceptors.cpp
+++ b/compiler-rt/lib/lsan/lsan_interceptors.cpp
@@ -84,6 +84,35 @@ INTERCEPTOR(void, free, void *p) {
   lsan_free(p);
 }
 
+#  if SANITIZER_INTERCEPT_FREE_SIZED
+INTERCEPTOR(void, free_sized, void *p, uptr size) {
+  if (UNLIKELY(!p))
+    return;
+  if (DlsymAlloc::PointerIsMine(p))
+    return DlsymAlloc::Free(p);
+  ENSURE_LSAN_INITED;
+  lsan_free_sized(p, size);
+}
+#    define LSAN_MAYBE_INTERCEPT_FREE_SIZED INTERCEPT_FUNCTION(free_sized)
+#  else
+#    define LSAN_MAYBE_INTERCEPT_FREE_SIZED
+#  endif
+
+#  if SANITIZER_INTERCEPT_FREE_ALIGNED_SIZED
+INTERCEPTOR(void, free_aligned_sized, void *p, uptr alignment, uptr size) {
+  if (UNLIKELY(!p))
+    return;
+  if (DlsymAlloc::PointerIsMine(p))
+    return DlsymAlloc::Free(p);
+  ENSURE_LSAN_INITED;
+  lsan_free_aligned_sized(p, alignment, size);
+}
+#    define LSAN_MAYBE_INTERCEPT_FREE_ALIGNED_SIZED \
+      INTERCEPT_FUNCTION(free_aligned_sized)
+#  else
+#    define LSAN_MAYBE_INTERCEPT_FREE_ALIGNED_SIZED
+#  endif
+
 INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) {
   if (DlsymAlloc::Use())
     return DlsymAlloc::Callocate(nmemb, size);
@@ -547,6 +576,8 @@ void InitializeInterceptors() {
 
   INTERCEPT_FUNCTION(malloc);
   INTERCEPT_FUNCTION(free);
+  LSAN_MAYBE_INTERCEPT_FREE_SIZED;
+  LSAN_MAYBE_INTERCEPT_FREE_ALIGNED_SIZED;
   LSAN_MAYBE_INTERCEPT_CFREE;
   INTERCEPT_FUNCTION(calloc);
   INTERCEPT_FUNCTION(realloc);
diff --git a/compiler-rt/lib/lsan/lsan_malloc_mac.cpp b/compiler-rt/lib/lsan/lsan_malloc_mac.cpp
index 525c30272ccca..8a16c053da238 100644
--- a/compiler-rt/lib/lsan/lsan_malloc_mac.cpp
+++ b/compiler-rt/lib/lsan/lsan_malloc_mac.cpp
@@ -44,16 +44,19 @@ using namespace __lsan;
   void *p = lsan_valloc(size, stack)
 #define COMMON_MALLOC_FREE(ptr) \
   lsan_free(ptr)
-#define COMMON_MALLOC_SIZE(ptr) \
-  uptr size = lsan_mz_size(ptr)
-#define COMMON_MALLOC_FILL_STATS(zone, stats)
-#define COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name) \
-  (void)zone_name; \
-  Report("mz_realloc(%p) -- attempting to realloc unallocated memory.\n", ptr);
-#define COMMON_MALLOC_NAMESPACE __lsan
-#define COMMON_MALLOC_HAS_ZONE_ENUMERATOR 0
-#define COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT 0
+#  define COMMON_MALLOC_FREE_SIZED(ptr, size) lsan_free_sized(ptr, size)
+#  define COMMON_MALLOC_FREE_ALIGNED_SIZED(ptr, alignment, size) \
+    lsan_free_aligned_sized(ptr, alignment, size)
+#  define COMMON_MALLOC_SIZE(ptr) uptr size = lsan_mz_size(ptr)
+#  define COMMON_MALLOC_FILL_STATS(zone, stats)
+#  define COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name)    \
+    (void)zone_name;                                                        \
+    Report("mz_realloc(%p) -- attempting to realloc unallocated memory.\n", \
+           ptr);
+#  define COMMON_MALLOC_NAMESPACE __lsan
+#  define COMMON_MALLOC_HAS_ZONE_ENUMERATOR 0
+#  define COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT 0
 
-#include "sanitizer_common/sanitizer_malloc_mac.inc"
+#  include "sanitizer_common/sanitizer_malloc_mac.inc"
 
 #endif // SANITIZER_APPLE
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_malloc_mac.inc b/compiler-rt/lib/sanitizer_common/sanitizer_malloc_mac.inc
index 6343eb284afbf..be27584f20535 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_malloc_mac.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_malloc_mac.inc
@@ -144,6 +144,22 @@ INTERCEPTOR(void, free, void *ptr) {
   COMMON_MALLOC_FREE(ptr);
 }
 
+#if SANITIZER_INTERCEPT_FREE_SIZED && defined(COMMON_MALLOC_FREE_SIZED)
+INTERCEPTOR(void, free_sized, void *ptr, size_t size) {
+  COMMON_MALLOC_ENTER();
+  COMMON_MALLOC_FREE_SIZED(ptr, size);
+}
+#endif
+
+#if SANITIZER_INTERCEPT_FREE_ALIGNED_SIZED && \
+    defined(COMMON_MALLOC_FREE_ALIGNED_SIZED)
+INTERCEPTOR(void, free_aligned_sized, void *ptr, size_t alignment,
+            size_t size) {
+  COMMON_MALLOC_ENTER();
+  COMMON_MALLOC_FREE_ALIGNED_SIZED(ptr, alignment, size);
+}
+#endif
+
 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
   COMMON_MALLOC_ENTER();
   COMMON_MALLOC_REALLOC(ptr, size);
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
index ccc808b60ca75..29987decdff45 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
@@ -663,6 +663,17 @@ SANITIZER_WEAK_IMPORT void *aligned_alloc(__sanitizer::usize __alignment,
 #define SANITIZER_INTERCEPT_GETSERVBYNAME_R SI_GLIBC
 #define SANITIZER_INTERCEPT_GETSERVBYPORT_R SI_GLIBC
 
+// Until free_sized and free_aligned_sized are more generally available,
+// we can only unconditionally intercept on ELF-based platforms where it
+// is okay to have undefined weak symbols.
+#ifdef __ELF__
+#  define SANITIZER_INTERCEPT_FREE_SIZED 1
+#  define SANITIZER_INTERCEPT_FREE_ALIGNED_SIZED 1
+#else
+#  define SANITIZER_INTERCEPT_FREE_SIZED 0
+#  define SANITIZER_INTERCEPT_FREE_ALIGNED_SIZED 0
+#endif
+
 // This macro gives a way for downstream users to override the above
 // interceptor macros irrespective of the platform they are on. They have
 // to do two things:
diff --git a/compiler-rt/test/sanitizer_common/TestCases/Linux/free_aligned_sized.c b/compiler-rt/test/sanitizer_common/TestCases/Linux/free_aligned_sized.c
index f4c6c0f973bdb..e9cb6f20c5ead 100644
--- a/compiler-rt/test/sanitizer_common/TestCases/Linux/free_aligned_sized.c
+++ b/compiler-rt/test/sanitizer_common/TestCases/Linux/free_aligned_sized.c
@@ -1,5 +1,5 @@
 // RUN: %clang -std=c23 -O0 %s -o %t && %run %t
-// UNSUPPORTED: asan, hwasan, rtsan, tsan, msan, lsan, ubsan
+// UNSUPPORTED: asan, hwasan, rtsan, tsan, msan, ubsan
 
 #include <stddef.h>
 #include <stdlib.h>
diff --git a/compiler-rt/test/sanitizer_common/TestCases/Linux/free_sized.c b/compiler-rt/test/sanitizer_common/TestCases/Linux/free_sized.c
index 0ee2289684d0a..8cdf3216e528a 100644
--- a/compiler-rt/test/sanitizer_common/TestCases/Linux/free_sized.c
+++ b/compiler-rt/test/sanitizer_common/TestCases/Linux/free_sized.c
@@ -1,5 +1,5 @@
 // RUN: %clang -std=c23 -O0 %s -o %t && %run %t
-// UNSUPPORTED: asan, hwasan, rtsan, tsan, msan, lsan, ubsan
+// UNSUPPORTED: asan, hwasan, rtsan, tsan, msan, ubsan
 
 #include <stddef.h>
 #include <stdlib.h>