Re: [PATCH] infiniband: avoid overflow warning

Doug Ledford
2017-08-18T16:40:05Z

On Mon, 2017-07-31 at 08:50 +0200, Arnd Bergmann wrote:
> A sockaddr_in structure on the stack getting passed into rdma_ip2gid
> triggers this warning, since we memcpy into a larger sockaddr_in6
> structure:
>
> In function 'memcpy',
> inlined from 'rdma_ip2gid' at include/rdma/ib_addr.h:175:3,
> inlined from 'addr_event.isra.4.constprop' at
> drivers/infiniband/core/roce_gid_mgmt.c:693:2,
> inlined from 'inetaddr_event' at
> drivers/infiniband/core/roce_gid_mgmt.c:716:9:
> include/linux/string.h:305:4: error: call to '__read_overflow2'
> declared with attribute error: detected read beyond size of object
> passed as 2nd parameter
>
> The warning seems appropriate here, but the code is also clearly
> correct, so we really just want to shut up this instance of the
> output.
>
> The best way I found so far is to avoid the memcpy() call and instead
> replace it with a struct assignment.
>
> Fixes: 6974f0c4555e ("include/linux/string.h: add the option of
> fortified string.h functions")
> Cc: Daniel Micay <danielmicay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Kees Cook <keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> Signed-off-by: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>

Thanks, applied.

--
Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
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