Commit 413d463f authored by Prasad J Pandit's avatar Prasad J Pandit Committed by Samuel Thibault
Browse files

slirp: check len against dhcp options array end 



While parsing dhcp options string in 'dhcp_decode', if an options'
length 'len' appeared towards the end of 'bp_vend' array, ensuing
read could lead to an OOB memory access issue. Add check to avoid it.

This is CVE-2017-11434.

Reported-by: default avatarReno Robert <renorobert@gmail.com>
Signed-off-by: default avatarPrasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: default avatarSamuel Thibault <samuel.thibault@ens-lyon.org>
parent 5c843af2

slirp/bootp.c

+3 −0
Original line number Diff line number Diff line
@@ -123,6 +123,9 @@ static void dhcp_decode(const struct bootp_t *bp, int *pmsg_type, 
            if (p >= p_end)

                break;

            len = *p++;

            if (p + len > p_end) {

                break;

            }

            DPRINTF("dhcp: tag=%d len=%d\n", tag, len);



            switch(tag) {