[PATCH 4.16 094/113] module: Fix display of wrong module .text address

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Thomas Richter <tmricht@xxxxxxxxxxxxx>

commit be71eda5383faa663efdba9ef54a6b8255e3c7f0 upstream.

Reading file /proc/modules shows the correct address:
[root@s35lp76 ~]# cat /proc/modules | egrep '^qeth_l2'
qeth_l2 94208 1 - Live 0x000003ff80401000

and reading file /sys/module/qeth_l2/sections/.text
[root@s35lp76 ~]# cat /sys/module/qeth_l2/sections/.text
0x0000000018ea8363
displays a random address.

This breaks the perf tool which uses this address on s390
to calculate start of .text section in memory.

Fix this by printing the correct (unhashed) address.

Thanks to Jessica Yu for helping on this.

Fixes: ef0010a30935 ("vsprintf: don't use 'restricted_pointer()' when not restricting")
Cc: <stable@xxxxxxxxxxxxxxx> # v4.15+
Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Cc: Jessica Yu <jeyu@xxxxxxxxxx>
Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/module.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1472,7 +1472,8 @@ static ssize_t module_sect_show(struct m
 {
 	struct module_sect_attr *sattr =
 		container_of(mattr, struct module_sect_attr, mattr);
-	return sprintf(buf, "0x%pK\n", (void *)sattr->address);
+	return sprintf(buf, "0x%px\n", kptr_restrict < 2 ?
+		       (void *)sattr->address : NULL);
 }
 
 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)