| Message ID | cfff1df64b18a89140ff995189c6a3c484815997.1322214950.git.ralf@linux-mips.org |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Fri, Nov 25, 2011 at 09:08:49AM +0000, Ralf Baechle wrote: > struct nr_route_struct's mnemonic permits a string of up to 7 bytes to be > used. If userland passes a not zero terminated string to the kernel adding > a node to the routing table might result in the kernel attempting to read > copy a too long string. > > Mnemonic is part of the NET/ROM routing protocol; NET/ROM routing table > updates only broadcast 6 bytes. The 7th byte in the mnemonic array exists > only as a \0 termination character for the kernel code's convenience. > > Fixed by rejecting mnemonic strings that have no terminating \0 in the first > 7 characters. Do this test only NETROM_NODE to avoid breaking NETROM_NEIGH > where userland might passing an uninitialized mnemonic field. Good point... I missed that. Acked-by: Dan Carpenter <dan.carpenter@oracle.com> regards, dan carpenter
From: Ralf Baechle <ralf@linux-mips.org> Date: Fri, 25 Nov 2011 09:08:49 +0000 > struct nr_route_struct's mnemonic permits a string of up to 7 bytes to be > used. If userland passes a not zero terminated string to the kernel adding > a node to the routing table might result in the kernel attempting to read > copy a too long string. > > Mnemonic is part of the NET/ROM routing protocol; NET/ROM routing table > updates only broadcast 6 bytes. The 7th byte in the mnemonic array exists > only as a \0 termination character for the kernel code's convenience. > > Fixed by rejecting mnemonic strings that have no terminating \0 in the first > 7 characters. Do this test only NETROM_NODE to avoid breaking NETROM_NEIGH > where userland might passing an uninitialized mnemonic field. > > Initial patch by Dan Carpenter <dan.carpenter@oracle.com>. > > Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c index 915a87b..8d7716c 100644 --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -678,6 +678,11 @@ int nr_rt_ioctl(unsigned int cmd, void __user *arg) } switch (nr_route.type) { case NETROM_NODE: + if (strnlen(nr_route.mnemonic, 7) == 7) { + ret = -EINVAL; + break; + } + ret = nr_add_node(&nr_route.callsign, nr_route.mnemonic, &nr_route.neighbour,
struct nr_route_struct's mnemonic permits a string of up to 7 bytes to be used. If userland passes a not zero terminated string to the kernel adding a node to the routing table might result in the kernel attempting to read copy a too long string. Mnemonic is part of the NET/ROM routing protocol; NET/ROM routing table updates only broadcast 6 bytes. The 7th byte in the mnemonic array exists only as a \0 termination character for the kernel code's convenience. Fixed by rejecting mnemonic strings that have no terminating \0 in the first 7 characters. Do this test only NETROM_NODE to avoid breaking NETROM_NEIGH where userland might passing an uninitialized mnemonic field. Initial patch by Dan Carpenter <dan.carpenter@oracle.com>. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Walter Harms <wharms@bfs.de> Cc: Thomas Osterried <thomas@osterried.de> --- net/netrom/nr_route.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)