From 68b7cb8febb2ad7123f165f9db10d3ffc3b409fe Mon Sep 17 00:00:00 2001 From: Juraj Sloboda Date: Tue, 16 Oct 2018 12:18:21 +0200 Subject: Fix buffer overflow when fragmenting packets (VPP-1383) Change-Id: Idcda9ae55fa2efb0b2e928bac3e8e86ff8d19eba Signed-off-by: Juraj Sloboda --- src/vnet/ip/ip_frag.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'src/vnet') diff --git a/src/vnet/ip/ip_frag.c b/src/vnet/ip/ip_frag.c index 628d9d66474..8de4dfc5d58 100644 --- a/src/vnet/ip/ip_frag.c +++ b/src/vnet/ip/ip_frag.c @@ -101,7 +101,8 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, ip4 = (ip4_header_t *) vlib_buffer_get_current (from_b); rem = clib_net_to_host_u16 (ip4->length) - sizeof (ip4_header_t); - max = (mtu - sizeof (ip4_header_t)) & ~0x7; + max = + (clib_min (mtu, VLIB_BUFFER_DATA_SIZE) - sizeof (ip4_header_t)) & ~0x7; if (rem > (vlib_buffer_length_in_chain (vm, from_b) - sizeof (ip4_header_t))) @@ -152,7 +153,7 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, ip4_header_t *to_ip4; u8 *to_data; - len = (rem > (mtu - sizeof (ip4_header_t)) ? max : rem); + len = (rem > max ? max : rem); if (len != rem) /* Last fragment does not need to divisible by 8 */ len &= ~0x7; if ((to_b = frag_buffer_alloc (org_from_b, &to_bi)) == 0) -- cgit 1.2.3-korg