From: Yehuda Sadeh <yehuda@redhat.com>
Date: Mon, 7 Nov 2016 23:42:04 +0000 (-0800)
Subject: os/bluestore: null terminate readlink() result
X-Git-Tag: v11.1.0~362^2~2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=bfdf2c62297a2a21d93646af65ae055e6eb90e8c;p=ceph.git

os/bluestore: null terminate readlink() result

readlink() does not guarantee null termination of
result.

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
---

diff --git a/src/os/bluestore/BlockDevice.cc b/src/os/bluestore/BlockDevice.cc
index 829b47e69414..bd2b09090ffa 100644
--- a/src/os/bluestore/BlockDevice.cc
+++ b/src/os/bluestore/BlockDevice.cc
@@ -46,9 +46,10 @@ void IOContext::aio_wait()
 BlockDevice *BlockDevice::create(const string& path, aio_callback_t cb, void *cbpriv)
 {
   string type = "kernel";
-  char buf[PATH_MAX];
-  int r = ::readlink(path.c_str(), buf, sizeof(buf));
+  char buf[PATH_MAX + 1];
+  int r = ::readlink(path.c_str(), buf, sizeof(buf) - 1);
   if (r >= 0) {
+    buf[r] = '\0';
     char *bname = ::basename(buf);
     if (strncmp(bname, SPDK_PREFIX, sizeof(SPDK_PREFIX)-1) == 0)
       type = "ust-nvme";