From mboxrd@z Thu Jan 1 00:00:00 1970 From: Helge Deller Date: Thu, 4 May 2017 20:23:46 +0200 Subject: [LTP] [PATCH] Fix getcwd03 testcase by zeroing target buffer for readlink() Message-ID: <20170504182346.GA4959@ls3530.fritz.box> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it According to the man(2) page of readlink(), a null byte is not appended to the target buffer. So applications need to make sure that the target buffer is zero-initialized, otherwise random bytes at the end of the returned string may exist. This patch zero-initializes the on-stack char array "link" and thus fixes the testcase failure of getcwd03 on the hppa/parisc architecture (and maybe others). Signed-off-by: Helge Deller -- testcases/kernel/syscalls/getcwd/getcwd03.c | 1 + 1 file changed, 1 insertion(+) diff --git a/testcases/kernel/syscalls/getcwd/getcwd03.c b/testcases/kernel/syscalls/getcwd/getcwd03.c index 4f8f872cf..ec1cacea9 100644 --- a/testcases/kernel/syscalls/getcwd/getcwd03.c +++ b/testcases/kernel/syscalls/getcwd/getcwd03.c @@ -74,6 +74,7 @@ static void verify_getcwd(void) } SAFE_CHDIR(".."); + memset(link, 0, sizeof(link)); SAFE_READLINK(dir_link, link, sizeof(link)); if (strcmp(link, SAFE_BASENAME(res1))) {