media: af9035: prevents buffer overflow when less than 3 bytes are written to
the device
When less than 3 bytes are written to the device, memcpy is called with
negative array size which leads to buffer overflow and kernel panic. This
patch adds a condition and returns -EOPNOTSUPP instead.
Fixes bugzilla issue 64871
Signed-off-by: Jozef Balga <jozef.ba...@gmail.com>
---
drivers/media/usb/dvb-usb-v2/af9035.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/media/usb/dvb-usb-v2/af9035.c
b/drivers/media/usb/dvb-usb-v2/af9035.c
index 666d319d3d1a..e509713db623 100644
--- a/drivers/media/usb/dvb-usb-v2/af9035.c
+++ b/drivers/media/usb/dvb-usb-v2/af9035.c
@@ -402,8 +402,9 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
if (msg[0].addr == state->af9033_i2c_addr[1])
reg |= 0x100000;
- ret = af9035_wr_regs(d, reg, &msg[0].buf[3],
- msg[0].len - 3);
+ ret = (msg[0].len > 3) ? af9035_wr_regs(d, reg,
+ &msg[0].buf[3], msg[0].len - 3)
+ : -EOPNOTSUPP;
} else {
/* I2C write */
u8 buf[MAX_XFER_SIZE];
--
2.14.4
