From bd275378d35b3535bc8b8321780b00e486c36d96 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Wed, 23 Sep 2015 20:22:33 +0000 Subject: [PATCH] avoid reading uninitialized memory in __map_file The value of *size is not relevant in case of failure, but it's better not to copy garbage from the stack into it. (The compiler cannot see through the syscall, so optimization was not affected by the unspecified value). --- src/time/__map_file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/time/__map_file.c b/src/time/__map_file.c index d06a5814..b91eb8ed 100644 --- a/src/time/__map_file.c +++ b/src/time/__map_file.c @@ -11,9 +11,10 @@ const char unsigned *__map_file(const char *pathname, size_t *size) const unsigned char *map = MAP_FAILED; int fd = __sys_open(pathname, O_RDONLY|O_CLOEXEC|O_NONBLOCK); if (fd < 0) return 0; - if (!__syscall(SYS_fstat, fd, &st)) + if (!__syscall(SYS_fstat, fd, &st)) { map = __mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0); + *size = st.st_size; + } __syscall(SYS_close, fd); - *size = st.st_size; return map == MAP_FAILED ? 0 : map; } -- 2.25.1