For b/5732800, expose calls from malloc to mmap,munmap, etc. (Forward-ported from cl/42670015)

README.google

@@ -278,3 +278,12 @@ sysdeps/generic/ldsodefs.h
   For Google b/8315591, experimental implementation of dlopen_with_offset.
   Forward-ported from cl/59286541, cl/59438930
   (ppluzhnikov, google-local)
+
+malloc/malloc.c
+ports/sysdeps/unix/sysv/linux/aarch64/nptl/localplt.data
+sysdeps/generic/localplt.data
+sysdeps/unix/sysv/linux/i386/nptl/localplt.data
+sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/localplt.data
+  For b/5732800, expose calls from malloc to mmap, munmap, and sbrk.
+  Forward ported from cl/42670015, with changes.
+  (ppluzhnikov, google-local)

malloc/malloc.c

@@ -398,8 +398,17 @@ __malloc_assert (const char *assertion, const char *file, unsigned int line,
 
 
 /* Definition for getting more memory from the OS.  */
+#if 0 /* Google-local: b/5732800: make calls go through PLT instead.  */
 #define MORECORE         (*__morecore)
 #define MORECORE_FAILURE 0
+#else
+#define __mmap           mmap
+#define __munmap         munmap
+#define __mremap         mremap
+#define __mprotect       mprotect
+#define MORECORE         sbrk
+#define MORECORE_FAILURE -1
+#endif
 void * __default_morecore (ptrdiff_t);
 void *(*__morecore)(ptrdiff_t) = __default_morecore;
 

ports/sysdeps/unix/sysv/linux/aarch64/nptl/localplt.data

@@ -5,7 +5,12 @@ libc.so: calloc
 libc.so: free
 libc.so: malloc
 libc.so: memalign
+libc.so: mmap
+libc.so: mprotect
+libc.so: mremap
+libc.so: munmap
 libc.so: realloc
+libc.so: sbrk
 libc.so: __signbit
 libc.so: __signbitl
 libm.so: matherr

sysdeps/generic/localplt.data

@@ -5,5 +5,10 @@ libc.so: calloc
 libc.so: free
 libc.so: malloc
 libc.so: memalign
+libc.so: mmap
+libc.so: mprotect
+libc.so: mremap
+libc.so: munmap
 libc.so: realloc
+libc.so: sbrk
 libm.so: matherr

sysdeps/unix/sysv/linux/i386/nptl/localplt.data

@@ -3,5 +3,10 @@ libc.so: calloc
 libc.so: free
 libc.so: malloc
 libc.so: memalign
+libc.so: mmap
+libc.so: mprotect
+libc.so: mremap
+libc.so: munmap
 libc.so: realloc
+libc.so: sbrk
 libm.so: matherr

sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/localplt.data

@@ -2,5 +2,10 @@ libc.so: calloc
 libc.so: free
 libc.so: malloc
 libc.so: memalign
+libc.so: mmap
+libc.so: mprotect
+libc.so: mremap
+libc.so: munmap
 libc.so: realloc
+libc.so: sbrk
 libm.so: matherr