From 6126f7a53c57485a9a29ddd772765695f23c92e6 Mon Sep 17 00:00:00 2001 From: Petr Uzel Date: Thu, 3 May 2012 21:02:01 +0200 Subject: libuuid: avoid double open and leaking descriptor We are opening /dev/urandom twice in uuid_generate(): first to check if the file is available and then later __uuid_generate_random() again to actually get the random data. Moreover, descriptor from the first open is leaking. Fix by passign the descriptor down the stack and reusing it there. References: http://marc.info/?l=util-linux-ng&m=133406051131131&w=2 Signed-off-by: Petr Uzel --- lib/randutils.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'lib/randutils.c') diff --git a/lib/randutils.c b/lib/randutils.c index b90c88691..0513798a0 100644 --- a/lib/randutils.c +++ b/lib/randutils.c @@ -58,13 +58,15 @@ int random_get_fd(void) * Use /dev/urandom if possible, and if not, * use glibc pseudo-random functions. */ -void random_get_bytes(void *buf, size_t nbytes) +void random_get_bytes(void *buf, size_t nbytes, int fd) { size_t i, n = nbytes; - int fd = random_get_fd(); int lose_counter = 0; unsigned char *cp = (unsigned char *) buf; + if (fd < 0) + fd = random_get_fd(); + if (fd >= 0) { while (n > 0) { ssize_t x = read(fd, cp, n); @@ -111,7 +113,7 @@ int main(int argc, char *argv[]) /* generate and print 10 random numbers */ for (i = 0; i < 10; i++) { - random_get_bytes(&v, sizeof(v)); + random_get_bytes(&v, sizeof(v), -1); printf("%d\n", v); } -- cgit v1.2.3-55-g7522