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Subject[patch -resend] spi/spidev: handle integer wrap in spidev_message()
"k_tmp->len" and "total" are unsigned integers.  The first message
could be close to "bufsiz" (4096) and then the next message could be
4GB which would cause an integer overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
I don't have a way to test this. I originally sent this message on Tue,
18 Oct 2011. I'm not totally sure what the implications are but it
seemed like there might be security implications. I honestly don't
know. I never received any feedback on the patch.

diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 830adbe..aab05e1 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -241,7 +241,7 @@ static int spidev_message(struct spidev_data *spidev,
k_tmp->len = u_tmp->len;

total += k_tmp->len;
- if (total > bufsiz) {
+ if (total > bufsiz || total < k_tmp->len) {
status = -EMSGSIZE;
goto done;
}

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