From 6b07d30aca7e52f2881b8c8c20c8a2cd28e8b3d3 Mon Sep 17 00:00:00 2001 From: Peter Huewe Date: Thu, 15 Sep 2011 14:37:43 -0300 Subject: [PATCH] TPM: Call tpm_transmit with correct size This patch changes the call of tpm_transmit by supplying the size of the userspace buffer instead of TPM_BUFSIZE. This got assigned CVE-2011-1161. [The first hunk didn't make sense given one could expect way less data than TPM_BUFSIZE, so added tpm_transmit boundary check over bufsiz instead The last parameter of tpm_transmit() reflects the amount of data expected from the device, and not the buffer size being supplied to it. It isn't ideal to parse it directly, so we just set it to the maximum the input buffer can handle and let the userspace API to do such job.] Signed-off-by: Rajiv Andrade Cc: Stable Kernel Signed-off-by: James Morris --- drivers/char/tpm/tpm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c index caf8012ef47c..1fe979335835 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -383,6 +383,9 @@ static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf, u32 count, ordinal; unsigned long stop; + if (bufsiz > TPM_BUFSIZE) + bufsiz = TPM_BUFSIZE; + count = be32_to_cpu(*((__be32 *) (buf + 2))); ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); if (count == 0) -- 2.20.1