From 5413b4c6c07b659e52c84a4e40d897b32b89834f Mon Sep 17 00:00:00 2001 From: Allan Stephens Date: Tue, 18 Jan 2011 13:24:55 -0500 Subject: [PATCH] tipc: Improve handling of invalid link tolerance values Enhances TIPC link code to ignore an invalid link tolerance value contained in an incoming LINK_PROTOCOL message, rather than processing the value and potentially causing a divide-by-zero error. Also add a compile-time check that catches attempts to redefine TIPC's minimum link tolerance value in a manner that might result in the same divide-by-zero error at run-time. Signed-off-by: Allan Stephens Signed-off-by: Paul Gortmaker --- include/linux/tipc_config.h | 4 ++++ net/tipc/link.c | 3 +++ 2 files changed, 7 insertions(+) diff --git a/include/linux/tipc_config.h b/include/linux/tipc_config.h index 7d42460a5e3c..c14102dee22e 100644 --- a/include/linux/tipc_config.h +++ b/include/linux/tipc_config.h @@ -193,6 +193,10 @@ #define TIPC_DEF_LINK_TOL 1500 #define TIPC_MAX_LINK_TOL 30000 +#if (TIPC_MIN_LINK_TOL < 16) +#error "TIPC_MIN_LINK_TOL is too small (abort limit may be NaN)" +#endif + /* * Link window limits (min, default, max), in packets */ diff --git a/net/tipc/link.c b/net/tipc/link.c index 1c5c53a81531..3c1c28cdbaa4 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -2617,6 +2617,9 @@ static void link_check_defragm_bufs(struct link *l_ptr) static void link_set_supervision_props(struct link *l_ptr, u32 tolerance) { + if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL)) + return; + l_ptr->tolerance = tolerance; l_ptr->continuity_interval = ((tolerance / 4) > 500) ? 500 : tolerance / 4; -- 2.39.5