3.2.92-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Alyssa Milburn <amilburn@xxxxxxxx>
commit 950e252cb469f323740d78e4907843acef89eedb upstream.
Otherwise the i2c transfer functions can read or write beyond the end of
stack or heap buffers.
Signed-off-by: Alyssa Milburn <amilburn@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
[bwh: Backported to 3.2:
- Use obuf instead of state->data
- Adjust filename, context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/media/dvb/dvb-usb/dw2102.c | 54 ++++++++++++++++++++++++++++++++++++++
1 file changed, 54 insertions(+)
--- a/drivers/media/dvb/dvb-usb/dw2102.c
+++ b/drivers/media/dvb/dvb-usb/dw2102.c
@@ -234,6 +234,20 @@ static int dw2102_serit_i2c_transfer(str
switch (num) {
case 2:
+ if (msg[0].len != 1) {
+ warn("i2c rd: len=%d is not 1!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
+ if (2 + msg[1].len > sizeof(buf6)) {
+ warn("i2c rd: len=%d is too big!\n",
+ msg[1].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
/* read si2109 register by number */
buf6[0] = msg[0].addr << 1;
buf6[1] = msg[0].len;
@@ -249,6 +263,13 @@ static int dw2102_serit_i2c_transfer(str
case 1:
switch (msg[0].addr) {
case 0x68:
+ if (2 + msg[0].len > sizeof(buf6)) {
+ warn("i2c wr: len=%d is too big!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
/* write to si2109 register */
buf6[0] = msg[0].addr << 1;
buf6[1] = msg[0].len;
@@ -292,6 +313,13 @@ static int dw2102_earda_i2c_transfer(str
/* first write first register number */
u8 ibuf[MAX_XFER_SIZE], obuf[3];
+ if (2 + msg[0].len != sizeof(obuf)) {
+ warn("i2c rd: len=%d is not 1!\n",
+ msg[0].len);
+ ret = -EOPNOTSUPP;
+ goto unlock;
+ }
+
if (2 + msg[1].len > sizeof(ibuf)) {
warn("i2c rd: len=%d is too big!\n",
msg[1].len);
@@ -492,6 +520,12 @@ static int dw3101_i2c_transfer(struct i2
/* first write first register number */
u8 ibuf[MAX_XFER_SIZE], obuf[3];
+ if (2 + msg[0].len != sizeof(obuf)) {
+ warn("i2c rd: len=%d is not 1!\n",
+ msg[0].len);
+ ret = -EOPNOTSUPP;
+ goto unlock;
+ }
if (2 + msg[1].len > sizeof(ibuf)) {
warn("i2c rd: len=%d is too big!\n",
msg[1].len);
@@ -718,6 +752,13 @@ static int su3000_i2c_transfer(struct i2
msg[0].buf[0] = ibuf[1];
break;
default:
+ if (3 + msg[0].len > sizeof(obuf)) {
+ warn("i2c wr: len=%d is too big!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
/* always i2c write*/
obuf[0] = 0x08;
obuf[1] = msg[0].addr;
@@ -733,6 +774,19 @@ static int su3000_i2c_transfer(struct i2
break;
case 2:
/* always i2c read */
+ if (4 + msg[0].len > sizeof(obuf)) {
+ warn("i2c rd: len=%d is too big!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+ if (1 + msg[1].len > sizeof(obuf)) {
+ warn("i2c rd: len=%d is too big!\n",
+ msg[1].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
obuf[0] = 0x09;
obuf[1] = msg[0].len;
obuf[2] = msg[1].len;