where is it broken ? Can you please explain ? Regards Santosh On Sun, Mar 4, 2012 at 5:48 PM, Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote: > On Thu, Mar 01, 2012 at 10:39:03PM +0530, santosh nayak wrote: >> From: Santosh Nayak <santoshprasadnayak@xxxxxxxxx> >> >> user-space ebtables expects 32 bytes-long names, but xt_match uses >> 29 bytes. Fill the remaining bytes with zeroes. >> >> Signed-off-by: Santosh Nayak <santoshprasadnayak@xxxxxxxxx> >> --- >> net/bridge/netfilter/ebtables.c | 14 +++++++++++--- >> 1 files changed, 11 insertions(+), 3 deletions(-) >> >> diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c >> index 5864cc4..21f337a 100644 >> --- a/net/bridge/netfilter/ebtables.c >> +++ b/net/bridge/netfilter/ebtables.c >> @@ -1335,7 +1335,10 @@ static inline int ebt_make_matchname(const struct ebt_entry_match *m, >> const char *base, char __user *ubase) >> { >> char __user *hlp = ubase + ((char *)m - base); >> - if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN)) >> + char name[EBT_FUNCTION_MAXNAMELEN] = {}; >> + >> + strncpy(name, m->u.match->name, sizeof(name)); >> + if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) >> return -EFAULT; >> return 0; >> } >> @@ -1344,7 +1347,10 @@ static inline int ebt_make_watchername(const struct ebt_entry_watcher *w, >> const char *base, char __user *ubase) >> { >> char __user *hlp = ubase + ((char *)w - base); >> - if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN)) >> + char name[EBT_FUNCTION_MAXNAMELEN] = {}; >> + >> + strncpy(name, w->u.watcher->name, sizeof(name)); >> + if (copy_to_user(hlp , name, EBT_FUNCTION_MAXNAMELEN)) >> return -EFAULT; >> return 0; >> } >> @@ -1355,10 +1361,12 @@ ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) >> int ret; >> char __user *hlp; >> const struct ebt_entry_target *t; >> + char name[EBT_FUNCTION_MAXNAMELEN] = {}; >> >> if (e->bitmask == 0) >> return 0; >> >> + strncpy(name, t->u.target->name, sizeof(name)); >> hlp = ubase + (((char *)e + e->target_offset) - base); >> t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); > > This is broken, t dereference is incorrect. Unfortunately I've applied > your patch. I'll apply a patch to fix this upon it. -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html