cbfstool: Fix crash on image without bootblock in end of ROM.
On platforms with CBFS data filling end of ROM image without bootblock in the
end (ex, ARM), calculation of "next valid entry" may exceed ROM image buffer in
memory and raise segmentation fault when we try to compare its magic value.
To fix this, always check if the entry address is inside ROM image buffer.
Verified to build and boot successfully on qemu/x86 and armv7/snow.
Change-Id: I117d6767a5403be636eea2b23be1dcf2e1c88839
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2330
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>
diff --git a/util/cbfstool/cbfs_image.c b/util/cbfstool/cbfs_image.c
index 5c2ac26..2cdbf23 100644
--- a/util/cbfstool/cbfs_image.c
+++ b/util/cbfstool/cbfs_image.c
@@ -112,7 +112,7 @@
struct cbfs_file *entry, *first = NULL, *last = NULL;
for (first = entry = cbfs_find_first_entry(image);
- entry && cbfs_is_valid_entry(entry);
+ entry && cbfs_is_valid_entry(image, entry);
entry = cbfs_find_next_entry(image, entry)) {
last = entry;
}
@@ -352,7 +352,7 @@
cbfs_walk(image, cbfs_merge_empty_entry, NULL);
for (entry = cbfs_find_first_entry(image);
- entry && cbfs_is_valid_entry(entry);
+ entry && cbfs_is_valid_entry(image, entry);
entry = cbfs_find_next_entry(image, entry)) {
entry_type = ntohl(entry->type);
@@ -429,7 +429,7 @@
struct cbfs_file *cbfs_get_entry(struct cbfs_image *image, const char *name) {
struct cbfs_file *entry;
for (entry = cbfs_find_first_entry(image);
- entry && cbfs_is_valid_entry(entry);
+ entry && cbfs_is_valid_entry(image, entry);
entry = cbfs_find_next_entry(image, entry)) {
if (strcasecmp(CBFS_NAME(entry), name) == 0) {
DEBUG("cbfs_get_entry: found %s\n", name);
@@ -574,7 +574,7 @@
struct cbfs_payload_segment *payload;
FILE *fp = (FILE *)arg;
- if (!cbfs_is_valid_entry(entry)) {
+ if (!cbfs_is_valid_entry(image, entry)) {
ERROR("cbfs_print_entry_info: Invalid entry at 0x%x\n",
cbfs_get_entry_addr(image, entry));
return -1;
@@ -643,7 +643,7 @@
next = cbfs_find_next_entry(image, entry);
- while (next && cbfs_is_valid_entry(next)) {
+ while (next && cbfs_is_valid_entry(image, next)) {
type = ntohl(next->type);
if (type == CBFS_COMPONENT_DELETED) {
type = CBFS_COMPONENT_NULL;
@@ -675,7 +675,7 @@
int count = 0;
struct cbfs_file *entry;
for (entry = cbfs_find_first_entry(image);
- entry && cbfs_is_valid_entry(entry);
+ entry && cbfs_is_valid_entry(image, entry);
entry = cbfs_find_next_entry(image, entry)) {
count ++;
if (callback(image, entry, arg) != 0)
@@ -730,7 +730,7 @@
struct cbfs_file *entry) {
uint32_t addr = cbfs_get_entry_addr(image, entry);
int align = ntohl(image->header->align);
- assert(entry && cbfs_is_valid_entry(entry));
+ assert(entry && cbfs_is_valid_entry(image, entry));
addr += ntohl(entry->offset) + ntohl(entry->len);
addr = align_up(addr, align);
return (struct cbfs_file *)(image->buffer.data + addr);
@@ -741,9 +741,13 @@
return (int32_t)((char *)entry - image->buffer.data);
}
-int cbfs_is_valid_entry(struct cbfs_file *entry) {
- return (entry &&memcmp(entry->magic, CBFS_FILE_MAGIC,
- sizeof(entry->magic)) == 0);
+int cbfs_is_valid_entry(struct cbfs_image *image, struct cbfs_file *entry) {
+ return (entry &&
+ (char *)entry >= image->buffer.data &&
+ (char *)entry + sizeof(entry->magic) <
+ image->buffer.data + image->buffer.size &&
+ memcmp(entry->magic, CBFS_FILE_MAGIC,
+ sizeof(entry->magic)) == 0);
}
int cbfs_init_entry(struct cbfs_file *entry,
@@ -818,7 +822,7 @@
* by ELF loader and positioned by cbfs_add_entry.
*/
for (entry = cbfs_find_first_entry(image);
- entry && cbfs_is_valid_entry(entry);
+ entry && cbfs_is_valid_entry(image, entry);
entry = cbfs_find_next_entry(image, entry)) {
uint32_t type = ntohl(entry->type);