On Sun, Sep 11, 2016 at 03:19:00PM +0300, Jarkko Sakkinen wrote: > tpm_write() does not check whether the buffer has at least enough space > for the header before passing it to tpm_transmit() so an overflow can > happen. > > Signed-off-by: Jarkko Sakkinen <[email protected]>
This is usable neither as read nor write primitive for an exploit. Still it makes sense to validate the input here. /Jarkko > --- > drivers/char/tpm/tpm-interface.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/char/tpm/tpm-interface.c > b/drivers/char/tpm/tpm-interface.c > index fd863ff..6a67f7f 100644 > --- a/drivers/char/tpm/tpm-interface.c > +++ b/drivers/char/tpm/tpm-interface.c > @@ -337,6 +337,9 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 > *buf, size_t bufsiz, > u32 count, ordinal; > unsigned long stop; > > + if (bufsiz < TPM_HEADER_SIZE) > + return -EINVAL; > + > if (bufsiz > TPM_BUFSIZE) > bufsiz = TPM_BUFSIZE; > > -- > 2.7.4 > ------------------------------------------------------------------------------ _______________________________________________ tpmdd-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
