afs: Clear pioctl data interchange buffer before use

Avoid leaking data in pioctl interchange buffers; clear the memory
when one is allocated.

FIXES 131892 (CVE-2015-3284)

(cherry picked from commit 592a99d6e693bc640e2bdfc2e7e5243fcedc8f93)

Change-Id: I90fef404978bd7aae3eb88836bcd4f95587fd45c

diff --git a/src/afs/afs_pioctl.c b/src/afs/afs_pioctl.c
index e9a84e3d2f983682dee0ba9469a23f029b7cc00b..89a56b97602806225645e0b8aec1adbea2c8164b 100644 (file)
--- a/src/afs/afs_pioctl.c
+++ b/src/afs/afs_pioctl.c
@@ -62,6 +62,11 @@ afs_pd_alloc(struct afs_pdata *apd, size_t size)
     if (apd->ptr == NULL)
        return ENOMEM;
 
+    if (size > AFS_LRALLOCSIZ)
+       memset(apd->ptr, 0, size + 1);
+    else
+       memset(apd->ptr, 0, AFS_LRALLOCSIZ);
+
     apd->remaining = size;
 
     return 0;