This is a note to let you know that I've just added the patch titled

tpm_i2c_infineon: fix potential buffer overruns caused by bit glitches on the bus

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: tpm_i2c_infineon-fix-potential-buffer-overruns-caused-by-bit-glitches-on-the-bus.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 9b8cb28d7c62568a5916bdd7ea1c9176d7f8f2ed Mon Sep 17 00:00:00 2001

From: Jeremy Boone jeremy.boone@nccgroup.trust Date: Thu, 8 Feb 2018 12:30:01 -0800 Subject: tpm_i2c_infineon: fix potential buffer overruns caused by bit glitches on the bus

From: Jeremy Boone jeremy.boone@nccgroup.trust

commit 9b8cb28d7c62568a5916bdd7ea1c9176d7f8f2ed upstream.

Discrete TPMs are often connected over slow serial buses which, on some platforms, can have glitches causing bit flips. In all the driver _recv() functions, we need to use a u32 to unmarshal the response size, otherwise a bit flip of the 31st bit would cause the expected variable to go negative, which would then try to read a huge amount of data. Also sanity check that the expected amount of data is large enough for the TPM header.

Signed-off-by: Jeremy Boone jeremy.boone@nccgroup.trust Cc: stable@vger.kernel.org Signed-off-by: James Bottomley James.Bottomley@HansenPartnership.com Reviewed-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com Signed-off-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com Signed-off-by: James Morris james.morris@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/char/tpm/tpm_i2c_infineon.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/char/tpm/tpm_i2c_infineon.c +++ b/drivers/char/tpm/tpm_i2c_infineon.c @@ -437,7 +437,8 @@ static int recv_data(struct tpm_chip *ch static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count) { int size = 0; - int expected, status; + int status; + u32 expected;

if (count < TPM_HEADER_SIZE) { size = -EIO; @@ -452,7 +453,7 @@ static int tpm_tis_i2c_recv(struct tpm_c }

expected = be32_to_cpu(*(__be32 *)(buf + 2)); - if ((size_t) expected > count) { + if (((size_t) expected > count) || (expected < TPM_HEADER_SIZE)) { size = -EIO; goto out; }

Patches currently in stable-queue which might be from jeremy.boone@nccgroup.trust are

queue-4.9/tpm_i2c_nuvoton-fix-potential-buffer-overruns-caused-by-bit-glitches-on-the-bus.patch queue-4.9/tpm-st33zp24-fix-potential-buffer-overruns-caused-by-bit-glitches-on-the-bus.patch queue-4.9/tpm_i2c_infineon-fix-potential-buffer-overruns-caused-by-bit-glitches-on-the-bus.patch queue-4.9/tpm_tis-fix-potential-buffer-overruns-caused-by-bit-glitches-on-the-bus.patch