[PKT_SCHED]: Fix illegal memory dereferences when dumping actions
The TCA_ACT_KIND attribute is used without checking its availability when dumping actions therefore leading to a value of 0x4 being dereferenced. The use of strcmp() in tc_lookup_action_n() isn't safe when fed with string from an attribute without enforcing proper NUL termination. Both bugs can be triggered with malformed netlink message and don't require any privileges. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
e340221acd
commit
26dab8930b
1 changed files with 5 additions and 6 deletions
|
@ -776,7 +776,7 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static char *
|
||||
static struct rtattr *
|
||||
find_dump_kind(struct nlmsghdr *n)
|
||||
{
|
||||
struct rtattr *tb1, *tb2[TCA_ACT_MAX+1];
|
||||
|
@ -804,7 +804,7 @@ find_dump_kind(struct nlmsghdr *n)
|
|||
return NULL;
|
||||
kind = tb2[TCA_ACT_KIND-1];
|
||||
|
||||
return (char *) RTA_DATA(kind);
|
||||
return kind;
|
||||
}
|
||||
|
||||
static int
|
||||
|
@ -817,16 +817,15 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
|
|||
struct tc_action a;
|
||||
int ret = 0;
|
||||
struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
|
||||
char *kind = find_dump_kind(cb->nlh);
|
||||
struct rtattr *kind = find_dump_kind(cb->nlh);
|
||||
|
||||
if (kind == NULL) {
|
||||
printk("tc_dump_action: action bad kind\n");
|
||||
return 0;
|
||||
}
|
||||
|
||||
a_o = tc_lookup_action_n(kind);
|
||||
a_o = tc_lookup_action(kind);
|
||||
if (a_o == NULL) {
|
||||
printk("failed to find %s\n", kind);
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
@ -834,7 +833,7 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
|
|||
a.ops = a_o;
|
||||
|
||||
if (a_o->walk == NULL) {
|
||||
printk("tc_dump_action: %s !capable of dumping table\n", kind);
|
||||
printk("tc_dump_action: %s !capable of dumping table\n", a_o->kind);
|
||||
goto rtattr_failure;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue