4.9-stable review patch. If anyone has any objections, please let me know.
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From: Jordan Niethe jniethe5@gmail.com
commit 7b62f9bd2246b7d3d086e571397c14ba52645ef1 upstream.
Currently the opal log is globally readable. It is kernel policy to limit the visibility of physical addresses / kernel pointers to root. Given this and the fact the opal log may contain this information it would be better to limit the readability to root.
Fixes: bfc36894a48b ("powerpc/powernv: Add OPAL message log interface") Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Jordan Niethe jniethe5@gmail.com Reviewed-by: Stewart Smith stewart@linux.ibm.com Reviewed-by: Andrew Donnellan andrew.donnellan@au1.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/powerpc/platforms/powernv/opal-msglog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/powerpc/platforms/powernv/opal-msglog.c +++ b/arch/powerpc/platforms/powernv/opal-msglog.c @@ -98,7 +98,7 @@ static ssize_t opal_msglog_read(struct f }
static struct bin_attribute opal_msglog_attr = { - .attr = {.name = "msglog", .mode = 0444}, + .attr = {.name = "msglog", .mode = 0400}, .read = opal_msglog_read };