From: Michael Ellerman <mpe@xxxxxxxxxxxxxx> [ Upstream commit 3546d8f1bbe992488ed91592cf6bf76e7114791a = The cxgb3 driver for "Chelsio T3-based gigabit and 10Gb Ethernet adapters" implements a custom ioctl as SIOCCHIOCTL/SIOCDEVPRIVATE in cxgb_extension_ioctl(). One of the subcommands of the ioctl is CHELSIO_GET_MEM, which appears to read memory directly out of the adapter and return it to userspace. It's not entirely clear what the contents of the adapter memory contains, but the assumption is that it shouldn't be accessible to all users. So add a CAP_NET_ADMIN check to the CHELSIO_GET_MEM case. Put it after the is_offload() check, which matches two of the other subcommands in the same function which also check for is_offload() and CAP_NET_ADMIN. Found by Ilja by code inspection, not tested as I don't have the required hardware. Reported-by: Ilja Van Sprundel <ivansprundel@xxxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c +++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c @@ -2437,6 +2437,8 @@ static int cxgb_extension_ioctl(struct n if (!is_offload(adapter)) return -EOPNOTSUPP; + if (!capable(CAP_NET_ADMIN)) + return -EPERM; if (!(adapter->flags & FULL_INIT_DONE)) return -EIO; /* need the memory controllers */ if (copy_from_user(&t, useraddr, sizeof(t)))
