diff --git a/VolumeManager.cpp b/VolumeManager.cpp
index f2e2d07..957d06b 100644
--- a/VolumeManager.cpp
+++ b/VolumeManager.cpp
@@ -191,7 +191,11 @@
     }
 
     memset(mountPath, 0, mountPathLen);
-    snprintf(mountPath, mountPathLen, "%s/%s", Volume::LOOPDIR, idHash);
+    int written = snprintf(mountPath, mountPathLen, "%s/%s", Volume::LOOPDIR, idHash);
+    if ((written < 0) || (written >= mountPathLen)) {
+        errno = EINVAL;
+        return -1;
+    }
 
     if (access(mountPath, F_OK)) {
         errno = ENOENT;
@@ -215,7 +219,13 @@
         return -1;
     }
 
-    snprintf(buffer, maxlen, "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(buffer, maxlen, "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (written >= maxlen)) {
+        SLOGE("getAsecMountPath failed for %s: couldn't construct path in buffer", id);
+        errno = EINVAL;
+        return -1;
+    }
+
     return 0;
 }
 
@@ -233,7 +243,12 @@
         return -1;
     }
 
-    snprintf(buffer, maxlen, "%s", asecFileName);
+    int written = snprintf(buffer, maxlen, "%s", asecFileName);
+    if ((written < 0) || (written >= maxlen)) {
+        errno = EINVAL;
+        return -1;
+    }
+
     return 0;
 }
 
@@ -281,7 +296,11 @@
 
     const char *asecDir = isExternal ? Volume::SEC_ASECDIR_EXT : Volume::SEC_ASECDIR_INT;
 
-    snprintf(asecFileName, sizeof(asecFileName), "%s/%s.asec", asecDir, id);
+    int written = snprintf(asecFileName, sizeof(asecFileName), "%s/%s.asec", asecDir, id);
+    if ((written < 0) || (size_t(written) >= sizeof(asecFileName))) {
+        errno = EINVAL;
+        return -1;
+    }
 
     if (!access(asecFileName, F_OK)) {
         SLOGE("ASEC file '%s' currently exists - destroy it first! (%s)",
@@ -381,7 +400,16 @@
         int formatStatus;
         char mountPoint[255];
 
-        snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+        int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+        if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+            SLOGE("ASEC fs format failed: couldn't construct mountPoint");
+            if (cleanupDm) {
+                Devmapper::destroy(idHash);
+            }
+            Loop::destroyByDevice(loopDevice);
+            unlink(asecFileName);
+            return -1;
+        }
 
         if (usingExt4) {
             formatStatus = Ext4::format(dmDevice, mountPoint);
@@ -475,7 +503,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("ASEC finalize failed: couldn't construct mountPoint");
+        return -1;
+    }
 
     int result = 0;
     if (sb.c_opts & ASEC_SB_C_OPTS_EXT4) {
@@ -528,7 +560,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("Unable remount to fix permissions for %s: couldn't construct mountpoint", id);
+        return -1;
+    }
 
     int result = 0;
     if ((sb.c_opts & ASEC_SB_C_OPTS_EXT4) == 0) {
@@ -621,14 +657,24 @@
 
     asprintf(&asecFilename2, "%s/%s.asec", dir, id2);
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id1);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id1);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("Rename failed: couldn't construct mountpoint");
+        goto out_err;
+    }
+
     if (isMountpointMounted(mountPoint)) {
         SLOGW("Rename attempt when src mounted");
         errno = EBUSY;
         goto out_err;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id2);
+    written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id2);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("Rename failed: couldn't construct mountpoint2");
+        goto out_err;
+    }
+
     if (isMountpointMounted(mountPoint)) {
         SLOGW("Rename attempt when dst mounted");
         errno = EBUSY;
@@ -665,7 +711,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("ASEC unmount failed for %s: couldn't construct mountpoint", id);
+        return -1;
+    }
 
     char idHash[33];
     if (!asecHash(id, idHash, sizeof(idHash))) {
@@ -685,7 +735,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::LOOPDIR, idHash);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::LOOPDIR, idHash);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("OBB unmount failed for %s: couldn't construct mountpoint", fileName);
+        return -1;
+    }
 
     return unmountLoopImage(fileName, idHash, fileName, mountPoint, force);
 }
@@ -781,7 +835,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("ASEC destroy failed for %s: couldn't construct mountpoint", id);
+        return -1;
+    }
 
     if (isMountpointMounted(mountPoint)) {
         if (mDebug) {
@@ -849,7 +907,8 @@
 
     if (asecPath != NULL) {
         int written = snprintf(asecPath, asecPathLen, "%s/%s", dir, asecName);
-        if (written < 0 || static_cast<size_t>(written) >= asecPathLen) {
+        if ((written < 0) || (size_t(written) >= asecPathLen)) {
+            SLOGE("findAsec failed for %s: couldn't construct ASEC path", id);
             free(asecName);
             return -1;
         }
@@ -868,7 +927,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::ASECDIR, id);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("ASEC mount failed: couldn't construct mountpoint", id);
+        return -1;
+    }
 
     if (isMountpointMounted(mountPoint)) {
         SLOGE("ASEC %s already mounted", id);
@@ -1011,7 +1074,11 @@
         return -1;
     }
 
-    snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::LOOPDIR, idHash);
+    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", Volume::LOOPDIR, idHash);
+    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
+        SLOGE("OBB mount failed: couldn't construct mountpoint", img);
+        return -1;
+    }
 
     if (isMountpointMounted(mountPoint)) {
         SLOGE("Image %s already mounted", img);
@@ -1223,10 +1290,15 @@
 
     int fd;
     char nodepath[255];
-    snprintf(nodepath,
+    int written = snprintf(nodepath,
              sizeof(nodepath), "/dev/block/vold/%d:%d",
              MAJOR(d), MINOR(d));
 
+    if ((written < 0) || (size_t(written) >= sizeof(nodepath))) {
+        SLOGE("shareVolume failed: couldn't construct nodepath");
+        return -1;
+    }
+
     if ((fd = open(MASS_STORAGE_FILE_PATH, O_WRONLY)) < 0) {
         SLOGE("Unable to open ums lunfile (%s)", strerror(errno));
         return -1;