| Message ID | 1495829844-69341-9-git-send-email-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 26, 2017 at 01:17:12PM -0700, Kees Cook wrote: > The NIU ethernet driver intentionally stores a page struct pointer on > top of the "mapping" field. Whitelist this case: > > drivers/net/ethernet/sun/niu.c: In function ‘niu_rx_pkt_ignore’: > drivers/net/ethernet/sun/niu.c:3402:10: note: found mismatched ssa struct pointer types: ‘struct page’ and ‘struct address_space’ > > *link = (struct page *) page->mapping; > ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Cc: David S. Miller <davem@davemloft.net> > Signed-off-by: Kees Cook <keescook@chromium.org> The driver really needs to stop doing this anyway. It would be good to send this out to linux-mm and netdev to come up with a better scheme.
On Sun, May 28, 2017 at 1:15 AM, Christoph Hellwig <hch@infradead.org> wrote: > On Fri, May 26, 2017 at 01:17:12PM -0700, Kees Cook wrote: >> The NIU ethernet driver intentionally stores a page struct pointer on >> top of the "mapping" field. Whitelist this case: >> >> drivers/net/ethernet/sun/niu.c: In function ‘niu_rx_pkt_ignore’: >> drivers/net/ethernet/sun/niu.c:3402:10: note: found mismatched ssa struct pointer types: ‘struct page’ and ‘struct address_space’ >> >> *link = (struct page *) page->mapping; >> ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> Cc: David S. Miller <davem@davemloft.net> >> Signed-off-by: Kees Cook <keescook@chromium.org> > > The driver really needs to stop doing this anyway. It would be good > to send this out to linux-mm and netdev to come up with a better scheme. Added to To. :) I couldn't understand why it was doing what it was doing, hence the whitelist entry. -Kees
[trying again with correct linux-mm address...] On Sun, May 28, 2017 at 1:15 AM, Christoph Hellwig <hch@infradead.org> wrote: > On Fri, May 26, 2017 at 01:17:12PM -0700, Kees Cook wrote: >> The NIU ethernet driver intentionally stores a page struct pointer on >> top of the "mapping" field. Whitelist this case: >> >> drivers/net/ethernet/sun/niu.c: In function ‘niu_rx_pkt_ignore’: >> drivers/net/ethernet/sun/niu.c:3402:10: note: found mismatched ssa struct pointer types: ‘struct page’ and ‘struct address_space’ >> >> *link = (struct page *) page->mapping; >> ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> Cc: David S. Miller <davem@davemloft.net> >> Signed-off-by: Kees Cook <keescook@chromium.org> > > The driver really needs to stop doing this anyway. It would be good > to send this out to linux-mm and netdev to come up with a better scheme. Added to To. :) I couldn't understand why it was doing what it was doing, hence the whitelist entry. -Kees
diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 5f4e59a78eeb..f777ead58ba8 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -43,6 +43,8 @@ struct whitelist_entry { }; static const struct whitelist_entry whitelist[] = { + /* NIU overloads mapping with page struct */ + { "drivers/net/ethernet/sun/niu.c", "page", "address_space" }, /* unix_skb_parms via UNIXCB() buffer */ { "net/unix/af_unix.c", "unix_skb_parms", "char" }, /* big_key payload.data struct splashing */
The NIU ethernet driver intentionally stores a page struct pointer on top of the "mapping" field. Whitelist this case: drivers/net/ethernet/sun/niu.c: In function ‘niu_rx_pkt_ignore’: drivers/net/ethernet/sun/niu.c:3402:10: note: found mismatched ssa struct pointer types: ‘struct page’ and ‘struct address_space’ *link = (struct page *) page->mapping; ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Kees Cook <keescook@chromium.org> --- scripts/gcc-plugins/randomize_layout_plugin.c | 2 ++ 1 file changed, 2 insertions(+)