5.10-stable review patch. If anyone has any objections, please let me know.
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From: Zhang Shurong zhang_shurong@foxmail.com
[ Upstream commit b97719a66970601cd3151a3e2020f4454a1c4ff6 ]
In gl861_i2c_master_xfer, msg is controlled by user. When msg[i].buf is null and msg[i].len is zero, former checks on msg[i].buf would be passed. Malicious data finally reach gl861_i2c_master_xfer. If accessing msg[i].buf[0] without sanity check, null ptr deref would happen. We add check on msg[i].len to prevent crash.
Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
Signed-off-by: Zhang Shurong zhang_shurong@foxmail.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/usb/dvb-usb-v2/gl861.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/usb/dvb-usb-v2/gl861.c b/drivers/media/usb/dvb-usb-v2/gl861.c index 0c434259c36f1..c71e7b93476de 100644 --- a/drivers/media/usb/dvb-usb-v2/gl861.c +++ b/drivers/media/usb/dvb-usb-v2/gl861.c @@ -120,7 +120,7 @@ static int gl861_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], } else if (num == 2 && !(msg[0].flags & I2C_M_RD) && (msg[1].flags & I2C_M_RD)) { /* I2C write + read */ - if (msg[0].len > 1 || msg[1].len > sizeof(ctx->buf)) { + if (msg[0].len != 1 || msg[1].len > sizeof(ctx->buf)) { ret = -EOPNOTSUPP; goto err; }