Prevent buffer overflows.
To eliminate possible buffer overflows some strcpy,
sprintf and strcat have been changed to strlcpy,
snprintf and strlcat.
Change-Id: Ieb9d4b600c894946a6492f8629ff39f2fcc106d3
Signed-off-by: Oskar Andero <oskar.andero@sonyericsson.com>
diff --git a/Devmapper.cpp b/Devmapper.cpp
index c9482bf..4d94e7b 100644
--- a/Devmapper.cpp
+++ b/Devmapper.cpp
@@ -19,6 +19,7 @@
#include <unistd.h>
#include <errno.h>
#include <string.h>
+#include <stdlib.h>
#include <sys/types.h>
#include <sys/ioctl.h>
@@ -34,6 +35,8 @@
#include "Devmapper.h"
+#define DEVMAPPER_BUFFER_SIZE 4096
+
int Devmapper::dumpState(SocketClient *c) {
char *buffer = (char *) malloc(1024 * 64);
@@ -43,7 +46,7 @@
}
memset(buffer, 0, (1024 * 64));
- char *buffer2 = (char *) malloc(4096);
+ char *buffer2 = (char *) malloc(DEVMAPPER_BUFFER_SIZE);
if (!buffer2) {
SLOGE("Error allocating memory (%s)", strerror(errno));
free(buffer);
@@ -81,9 +84,9 @@
do {
n = (struct dm_name_list *) (((char *) n) + nxt);
- memset(buffer2, 0, 4096);
+ memset(buffer2, 0, DEVMAPPER_BUFFER_SIZE);
struct dm_ioctl *io2 = (struct dm_ioctl *) buffer2;
- ioctlInit(io2, 4096, n->name, 0);
+ ioctlInit(io2, DEVMAPPER_BUFFER_SIZE, n->name, 0);
if (ioctl(fd, DM_DEV_STATUS, io2)) {
if (errno != ENXIO) {
SLOGE("DM_DEV_STATUS ioctl failed (%s)", strerror(errno));
@@ -120,12 +123,14 @@
io->version[2] = 0;
io->flags = flags;
if (name) {
- strncpy(io->name, name, sizeof(io->name));
+ int ret = strlcpy(io->name, name, sizeof(io->name));
+ if (ret >= sizeof(io->name))
+ abort();
}
}
int Devmapper::lookupActive(const char *name, char *ubuffer, size_t len) {
- char *buffer = (char *) malloc(4096);
+ char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE);
if (!buffer) {
SLOGE("Error allocating memory (%s)", strerror(errno));
return -1;
@@ -140,7 +145,7 @@
struct dm_ioctl *io = (struct dm_ioctl *) buffer;
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
if (ioctl(fd, DM_DEV_STATUS, io)) {
if (errno != ENXIO) {
SLOGE("DM_DEV_STATUS ioctl failed for lookup (%s)", strerror(errno));
@@ -159,7 +164,7 @@
int Devmapper::create(const char *name, const char *loopFile, const char *key,
unsigned int numSectors, char *ubuffer, size_t len) {
- char *buffer = (char *) malloc(4096);
+ char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE);
if (!buffer) {
SLOGE("Error allocating memory (%s)", strerror(errno));
return -1;
@@ -175,7 +180,7 @@
struct dm_ioctl *io = (struct dm_ioctl *) buffer;
// Create the DM device
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
if (ioctl(fd, DM_DEV_CREATE, io)) {
SLOGE("Error creating device mapping (%s)", strerror(errno));
@@ -185,7 +190,7 @@
}
// Set the legacy geometry
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
char *geoParams = buffer + sizeof(struct dm_ioctl);
// bps=512 spc=8 res=32 nft=2 sec=8190 mid=0xf0 spt=63 hds=64 hid=0 bspf=8 rdcl=2 infs=1 bkbs=2
@@ -200,7 +205,7 @@
}
// Retrieve the device number we were allocated
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
if (ioctl(fd, DM_DEV_STATUS, io)) {
SLOGE("Error retrieving devmapper status (%s)", strerror(errno));
free(buffer);
@@ -215,17 +220,19 @@
struct dm_target_spec *tgt;
tgt = (struct dm_target_spec *) &buffer[sizeof(struct dm_ioctl)];
- ioctlInit(io, 4096, name, DM_STATUS_TABLE_FLAG);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, DM_STATUS_TABLE_FLAG);
io->target_count = 1;
tgt->status = 0;
tgt->sector_start = 0;
tgt->length = numSectors;
- strcpy(tgt->target_type, "crypt");
+ strlcpy(tgt->target_type, "crypt", sizeof(tgt->target_type));
char *cryptParams = buffer + sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec);
- sprintf(cryptParams, "twofish %s 0 %s 0", key, loopFile);
+ snprintf(cryptParams,
+ DEVMAPPER_BUFFER_SIZE - (sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec)),
+ "twofish %s 0 %s 0", key, loopFile);
cryptParams += strlen(cryptParams) + 1;
cryptParams = (char *) _align(cryptParams, 8);
tgt->next = cryptParams - buffer;
@@ -238,7 +245,7 @@
}
// Resume the new table
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
if (ioctl(fd, DM_DEV_SUSPEND, io)) {
SLOGE("Error Resuming (%s)", strerror(errno));
@@ -254,7 +261,7 @@
}
int Devmapper::destroy(const char *name) {
- char *buffer = (char *) malloc(4096);
+ char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE);
if (!buffer) {
SLOGE("Error allocating memory (%s)", strerror(errno));
return -1;
@@ -270,7 +277,7 @@
struct dm_ioctl *io = (struct dm_ioctl *) buffer;
// Create the DM device
- ioctlInit(io, 4096, name, 0);
+ ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0);
if (ioctl(fd, DM_DEV_REMOVE, io)) {
if (errno != ENXIO) {