diff options
| author |   Alexander Duyck <alexander.h.duyck@redhat.com> | 2015-03-12 14:46:23 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2015-03-12 18:26:51 -0400 |
| commit | 3c9e9f7320f0138497ef7879c0903246746e0ed3 (patch) | |
| tree | eea60b4c1788a31f550af86c8afccd9e616f9ebf | |
| parent | ebpf: verifier: check that call reg with ARG_ANYTHING is initialized (diff) | |
| download | linux-dev-3c9e9f7320f0138497ef7879c0903246746e0ed3.tar.xz linux-dev-3c9e9f7320f0138497ef7879c0903246746e0ed3.zip | |
fib_trie: Avoid NULL pointer if local table is not allocated
The function fib_unmerge assumed the local table had already been
allocated. If that is not the case however when custom rules are applied
then this can result in a NULL pointer dereference.
In order to prevent this we must check the value of the local table pointer
and if it is NULL simply return 0 as there is no local table to separate
from the main.
Fixes: 0ddcf43d5 ("ipv4: FIB Local/MAIN table collapse")
Reported-by: Madhu Challa <challa@noironetworks.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/fib_frontend.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index c1caf9ded280..e5b6b0534c5f 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -156,9 +156,12 @@ int fib_unmerge(struct net *net) { struct fib_table *old, *new; + /* attempt to fetch local table if it has been allocated */ old = fib_get_table(net, RT_TABLE_LOCAL); - new = fib_trie_unmerge(old); + if (!old) + return 0; + new = fib_trie_unmerge(old); if (!new) return -ENOMEM; |