We cannot compute the gap until we know we have a 'struct ebt_entry'
and not 'struct ebt_entries'. Failure to check can cause crash.
Tested by Santiago Garcia Mantinan <[email protected]>
Signed-off-by: Chuck Ebbert <[email protected]>
---
Can we get this upstream quickly? The bug's also in 2.6.19.1 and
2.6.18.6.
--- 2.6.20-rc1-32smp.orig/net/bridge/netfilter/ebtables.c
+++ 2.6.20-rc1-32smp/net/bridge/netfilter/ebtables.c
@@ -610,7 +610,7 @@ ebt_check_entry(struct ebt_entry *e, str
struct ebt_entry_target *t;
struct ebt_target *target;
unsigned int i, j, hook = 0, hookmask = 0;
- size_t gap = e->next_offset - e->target_offset;
+ size_t gap;
int ret;
/* don't mess with the struct ebt_entries */
@@ -660,6 +660,7 @@ ebt_check_entry(struct ebt_entry *e, str
if (ret != 0)
goto cleanup_watchers;
t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+ gap = e->next_offset - e->target_offset;
target = find_target_lock(t->u.name, &ret, &ebt_mutex);
if (!target)
goto cleanup_watchers;
--
MBTI: IXTP