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  • Vladyslav Tarasiuk's avatar
    mqprio: Fix out-of-bounds access in mqprio_dump · 9f104c77
    Vladyslav Tarasiuk authored
    When user runs a command like
    tc qdisc add dev eth1 root mqprio
    KASAN stack-out-of-bounds warning is emitted.
    Currently, NLA_ALIGN macro used in mqprio_dump provides too large
    buffer size as argument for nla_put and memcpy down the call stack.
    The flow looks like this:
    1. nla_put expects exact object size as an argument;
    2. Later it provides this size to memcpy;
    3. To calculate correct padding for SKB, nla_put applies NLA_ALIGN
       macro itself.
    
    Therefore, NLA_ALIGN should not be applied to the nla_put parameter.
    Otherwise it will lead to out-of-bounds memory access in memcpy.
    
    Fixes: 4e8b86c0
    
     ("mqprio: Introduce new hardware offload mode and shaper in mqprio")
    Signed-off-by: default avatarVladyslav Tarasiuk <vladyslavt@mellanox.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    9f104c77