sh: Fix mmap2 for handling differing PAGE_SIZEs.
mmap2 uses a fixed page shift of 12, regardless of the PAGE_SIZE setting.
Fix up the mmap2 code to add some sanity checks on the mapping, and to
update pgoff accordingly.
Error handling bits based on 4280e3126f641898f0ed1a931645373d3489e2a6
("frv: fix mmap2 error handling").
Signed-off-by: Toshinobu Sugioka <sugioka@itonet.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
index 58dfc02..e3a7e36 100644
--- a/arch/sh/kernel/sys_sh.c
+++ b/arch/sh/kernel/sys_sh.c
@@ -63,6 +63,15 @@
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
{
+ /*
+ * The shift for mmap2 is constant, regardless of PAGE_SIZE
+ * setting.
+ */
+ if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
+ return -EINVAL;
+
+ pgoff >>= PAGE_SHIFT - 12;
+
return do_mmap2(addr, len, prot, flags, fd, pgoff);
}