commit: 529a388ebb1b4e9d6ad8a1bb61dd8211833a5976 Author: Denis Lisov <dennis.lissov <AT> gmail <DOT> com> AuthorDate: Sat Dec 19 16:13:58 2015 +0000 Commit: Mike Frysinger <vapier <AT> gentoo <DOT> org> CommitDate: Sat Dec 19 17:57:53 2015 +0000 URL: https://gitweb.gentoo.org/proj/sandbox.git/commit/?id=529a388e
libsandbox: fix old_malloc_size check on realloc Realloc uses SB_MALLOC_TO_SIZE assuming it returns the usable size, while it is really the mmap size, which is greater. Thus it may fail to reallocate even if required. URL: https://bugs.gentoo.org/568714 Signed-off-by: Denis Lisov <dennis.lissov <AT> gmail.com> Signed-off-by: Mike Frysinger <vapier <AT> gentoo.org> libsandbox/memory.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/libsandbox/memory.c b/libsandbox/memory.c index 8581128..a2d69a2 100644 --- a/libsandbox/memory.c +++ b/libsandbox/memory.c @@ -40,7 +40,8 @@ static int sb_munmap(void *addr, size_t length) #define SB_MALLOC_TO_MMAP(ptr) ((void*)((uintptr_t)(ptr) - MIN_ALIGN)) #define SB_MMAP_TO_MALLOC(ptr) ((void*)((uintptr_t)(ptr) + MIN_ALIGN)) -#define SB_MALLOC_TO_SIZE(ptr) (*((size_t*)SB_MALLOC_TO_MMAP(ptr))) +#define SB_MALLOC_TO_MMAP_SIZE(ptr) (*((size_t*)SB_MALLOC_TO_MMAP(ptr))) +#define SB_MALLOC_TO_SIZE(ptr) (SB_MALLOC_TO_MMAP_SIZE(ptr) - MIN_ALIGN) void *malloc(size_t size) { @@ -57,7 +58,7 @@ void free(void *ptr) { if (ptr == NULL) return; - if (munmap(SB_MALLOC_TO_MMAP(ptr), SB_MALLOC_TO_SIZE(ptr))) + if (munmap(SB_MALLOC_TO_MMAP(ptr), SB_MALLOC_TO_MMAP_SIZE(ptr))) sb_ebort("sandbox memory corruption with free(%p): %s\n", ptr, strerror(errno)); }
