From 6bb5699d2b59491097bc21ffa3c097cdd4853f89 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Fri, 28 May 2021 10:41:43 -0400 Subject: [PATCH] libradius: Fix attribute length validation in rad_get_attr(3) The length of the attribute header needs to be excluded when comparing the attribute length against the length of the packet. Otherwise, validation may incorrectly fail when fetching the final attribute in a message. Fixes: 8d5c78130 ("libradius: Fix input validation bugs") Reported by: Peter Eriksson Tested by: Peter Eriksson MFC after: now Sponsored by: The FreeBSD Foundation --- lib/libradius/radlib.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/lib/libradius/radlib.c b/lib/libradius/radlib.c index 18aee8b5302..4d21887c4ee 100644 --- a/lib/libradius/radlib.c +++ b/lib/libradius/radlib.c @@ -964,7 +964,12 @@ rad_get_attr(struct rad_handle *h, const void **value, size_t *lenp) } type = h->in[h->in_pos++]; len = h->in[h->in_pos++]; - if (len < 2 || h->in_pos + len > h->in_len) { + if (len < 2) { + generr(h, "Malformed attribute in response"); + return -1; + } + len -= 2; + if (h->in_pos + len > h->in_len) { generr(h, "Malformed attribute in response"); return -1; }