Re: [dpdk-dev] [PATCH] lpm: fix overflow issue

["Richardson, Bruce" <bruce.richardson@intel.com>]

Sorry I missed this Friday. I'll look at it  shortly.



On 21 Feb 2015, at 22:56, Igor Ryzhov <iryzhov@nfware.com<mailto:iryzhov@nfware.com>> wrote:

Hello again. Will anybody review this patch?
This is really critical issue, because it can lead to memory corruption and break any program using LPM.

CCing this to Bruce Richardson, because he is maintainer of LPM.

Regards,
Igor Ryzhov

On Fri, Feb 20, 2015 at 4:16 PM, Igor Ryzhov <iryzhov@nfware.com<mailto:iryzhov@nfware.com>> wrote:
LPM table overflow may occur if table is full and added rule has the biggest depth that already have some rules.

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com<mailto:iryzhov@nfware.com>>
---
 lib/librte_lpm/rte_lpm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c
index 983e04b..cc51210 100644
--- a/lib/librte_lpm/rte_lpm.c
+++ b/lib/librte_lpm/rte_lpm.c
@@ -298,6 +298,9 @@ rule_add(struct rte_lpm *lpm, uint32_t ip_masked, uint8_t depth,
                                return rule_index;
                        }
                }
+
+               if (rule_index == lpm->max_rules)
+                       return -ENOSPC;
        } else {
                /* Calculate the position in which the rule will be stored. */
                rule_index = 0;
--
1.9.3 (Apple Git-50)




--
Regards,
Igor Ryzhov