Thread (4 messages) 4 messages, 4 authors, 2017-07-04

Re: 'skb' buffer address information leakage

flat view

From: Jakub Kicinski <hidden>
Date: 2017-07-04 05:27:50
Also in: linux-wireless, lkml

On Tue, 4 Jul 2017 13:12:18 +0800, Dison River wrote:
drivers/net/ethernet/netronome/nfp/nfp_net_debugfs.c:167
         seq_printf(file, " frag=%p", skb);
FWIW that's actually not a skb pointer.  The structure is defined like
this:

struct nfp_net_tx_buf {
        union { 
                struct sk_buff *skb;
                void *frag;
        };
        dma_addr_t dma_addr;
        short int fidx;
        u16 pkt_cnt;
        u32 real_len;
};

So the line in question is actually reading the frag pointer, I just
reused the skb variable, because this has to be read via READ_ONCE()
and NULL-checked so I thought that doing it separately for skb and
frag is a waste of LOC especially in debug code.  I will queue up a
clean up for after the merge window.

Thanks!
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help