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 <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This commit is contained in:
Allan Stephens 2011-01-18 13:24:55 -05:00 committed by Paul Gortmaker
parent 3f8dd9446e
commit 5413b4c6c0
2 changed files with 7 additions and 0 deletions

View File

@ -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
*/

View File

@ -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;