• Hauke Mehrtens's avatar
    net: Fix for_each_netdev_feature on Big endian · b2975c2e
    Hauke Mehrtens authored
    [ Upstream commit 3b89ea9c ]
    
    The features attribute is of type u64 and stored in the native endianes on
    the system. The for_each_set_bit() macro takes a pointer to a 32 bit array
    and goes over the bits in this area. On little Endian systems this also
    works with an u64 as the most significant bit is on the highest address,
    but on big endian the words are swapped. When we expect bit 15 here we get
    bit 47 (15 + 32).
    
    This patch converts it more or less to its own for_each_set_bit()
    implementation which works on 64 bit integers directly. This is then
    completely in host endianness and should work like expected.
    
    Fixes: fd867d51 ("net/core: generic support for disabling netdev features down stack")
    Signed-off-by: default avatarHauke Mehrtens <hauke.mehrtens@intel.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
    b2975c2e
dev.c 242 KB