From 446b4207cc7a30d8a4d5b2445a5a1b27d440f55d Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Fri, 18 Feb 2011 17:04:56 -0500 Subject: major improvements to temp file name generator use current time in nanoseconds and some potentially-random (if aslr is enabled) pointer values for the initial tempfile name generation, and step via a cheap linear prng on collisions. limit the number of retry attempts to prevent denial of service attacks even if an attacker can guess the filenames. --- src/temp/mkdtemp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'src/temp/mkdtemp.c') diff --git a/src/temp/mkdtemp.c b/src/temp/mkdtemp.c index 162d98b0..f2ecc510 100644 --- a/src/temp/mkdtemp.c +++ b/src/temp/mkdtemp.c @@ -12,7 +12,8 @@ char *__mktemp(char *); char *mkdtemp(char *template) { - for (;;) { + int retries = 100; + while (retries--) { if (!__mktemp(template)) return 0; if (!mkdir(template, 0700)) return template; if (errno != EEXIST) return 0; @@ -20,4 +21,5 @@ char *mkdtemp(char *template) * that we have a valid template string */ strcpy(template+strlen(template)-6, "XXXXXX"); } + return 0; } -- cgit v1.2.1