xc2028 unaligned access fixes

From: Al Viro <viro@ftp.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 14 insertions, 11 deletions

diff --git a/linux/drivers/media/common/tuners/tuner-xc2028.c b/linux/drivers/media/common/tuners/tuner-xc2028.c
index 6a9742552..c51a7b4c8 100644
--- a/linux/drivers/media/common/tuners/tuner-xc2028.c
+++ b/linux/drivers/media/common/tuners/tuner-xc2028.c
@@ -20,6 +20,7 @@
 #include <asm/semaphore.h>
 #endif
 #include "compat.h"
+#include <asm/unaligned.h>
 #include "tuner-i2c.h"
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 5, 0)
 #include "i2c-compat.h"
@@ -307,10 +308,10 @@ static int load_all_firmwares(struct dvb_frontend *fe)
 	name[sizeof(name) - 1] = 0;
 	p += sizeof(name) - 1;
 
-	priv->firm_version = le16_to_cpu(*(__u16 *) p);
+	priv->firm_version = get_unaligned_le16(p);
 	p += 2;
 
-	n_array = le16_to_cpu(*(__u16 *) p);
+	n_array = get_unaligned_le16(p);
 	p += 2;
 
 	tuner_info("Loading %d firmware images from %s, type: %s, ver %d.%d\n",
@@ -339,26 +340,26 @@ static int load_all_firmwares(struct dvb_frontend *fe)
 		}
 
 		/* Checks if there's enough bytes to read */
-		if (p + sizeof(type) + sizeof(id) + sizeof(size) > endp) {
-			tuner_err("Firmware header is incomplete!\n");
-			goto corrupt;
-		}
+		if (endp - p < sizeof(type) + sizeof(id) + sizeof(size))
+			goto header;
 
-		type = le32_to_cpu(*(__u32 *) p);
+		type = get_unaligned_le32(p);
 		p += sizeof(type);
 
-		id = le64_to_cpu(*(v4l2_std_id *) p);
+		id = get_unaligned_le64(p);
 		p += sizeof(id);
 
 		if (type & HAS_IF) {
-			int_freq = le16_to_cpu(*(__u16 *) p);
+			int_freq = get_unaligned_le16(p);
 			p += sizeof(int_freq);
+			if (endp - p < sizeof(size))
+				goto header;
 		}
 
-		size = le32_to_cpu(*(__u32 *) p);
+		size = get_unaligned_le32(p);
 		p += sizeof(size);
 
-		if ((!size) || (size + p > endp)) {
+		if (!size || size > endp - p) {
 			tuner_err("Firmware type ");
 			dump_firm_type(type);
 			printk("(%x), id %llx is corrupted "
@@ -397,6 +398,8 @@ static int load_all_firmwares(struct dvb_frontend *fe)
 
 	goto done;
 
+header:
+	tuner_err("Firmware header is incomplete!\n");
 corrupt:
 	rc = -EINVAL;
 	tuner_err("Error: firmware file is corrupted!\n");