The patch below does not apply to the 3.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 950e252cb469f323740d78e4907843acef89eedb Mon Sep 17 00:00:00 2001
From: Alyssa Milburn <amilburn@xxxxxxxx>
Date: Sat, 1 Apr 2017 14:34:49 -0300
Subject: [PATCH] [media] dw2102: limit messages to buffer size
Otherwise the i2c transfer functions can read or write beyond the end of
stack or heap buffers.
Signed-off-by: Alyssa Milburn <amilburn@xxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
diff --git a/drivers/media/usb/dvb-usb/dw2102.c b/drivers/media/usb/dvb-usb/dw2102.c
index 4f42d57f81d9..6e654e5026dd 100644
--- a/drivers/media/usb/dvb-usb/dw2102.c
+++ b/drivers/media/usb/dvb-usb/dw2102.c
@@ -204,6 +204,20 @@ static int dw2102_serit_i2c_transfer(struct i2c_adapter *adap,
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;
@@ -219,6 +233,13 @@ static int dw2102_serit_i2c_transfer(struct i2c_adapter *adap,
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;
@@ -262,6 +283,13 @@ static int dw2102_earda_i2c_transfer(struct i2c_adapter *adap, struct i2c_msg ms
/* 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);
@@ -462,6 +490,12 @@ static int dw3101_i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],
/* 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);
@@ -696,6 +730,13 @@ static int su3000_i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],
msg[0].buf[0] = state->data[1];
break;
default:
+ if (3 + msg[0].len > sizeof(state->data)) {
+ warn("i2c wr: len=%d is too big!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
/* always i2c write*/
state->data[0] = 0x08;
state->data[1] = msg[0].addr;
@@ -711,6 +752,19 @@ static int su3000_i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],
break;
case 2:
/* always i2c read */
+ if (4 + msg[0].len > sizeof(state->data)) {
+ warn("i2c rd: len=%d is too big!\n",
+ msg[0].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+ if (1 + msg[1].len > sizeof(state->data)) {
+ warn("i2c rd: len=%d is too big!\n",
+ msg[1].len);
+ num = -EOPNOTSUPP;
+ break;
+ }
+
state->data[0] = 0x09;
state->data[1] = msg[0].len;
state->data[2] = msg[1].len;