• Dmitry Safonov's avatar
    netlink: Don't shift on 64 for ngroups · 91874ecf
    Dmitry Safonov authored
    It's legal to have 64 groups for netlink_sock.
    
    As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe
    only to first 32 groups.
    
    The check for correctness of .bind() userspace supplied parameter
    is done by applying mask made from ngroups shift. Which broke Android
    as they have 64 groups and the shift for mask resulted in an overflow.
    
    Fixes: 61f4b237 ("netlink: Don't shift with UB on nlk->ngroups")
    Cc: "David S. Miller" <davem@davemloft.net>
    Cc: Herbert Xu <herbert@gondor.apana.org.au>
    Cc: Steffen Klassert <steffen.klassert@secunet.com>
    Cc: netdev@vger.kernel.org
    Cc: stable@vger.kernel.org
    Reported-and-Tested-by: default avatarNathan Chancellor <natechancellor@gmail.com>
    Signed-off-by: default avatarDmitry Safonov <dima@arista.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    91874ecf
af_netlink.c 64.7 KB