binfmt_flat: flat_{get,put}_addr_from_rp() should be able to fail

on MMU targets EFAULT is possible here.  Make both return 0 or error,
passing what used to be the return value of flat_get_addr_from_rp()
by reference.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 21 insertions, 17 deletions

diff --git a/arch/blackfin/include/asm/flat.h b/arch/blackfin/include/asm/flat.h
index c1314c5..296d7f5 100644
--- a/arch/blackfin/include/asm/flat.h
+++ b/arch/blackfin/include/asm/flat.h
@@ -14,23 +14,28 @@
 #define	flat_argvp_envp_on_stack()		0
 #define	flat_old_ram_flag(flags)		(flags)
 
-extern unsigned long bfin_get_addr_from_rp (unsigned long *ptr,
-					unsigned long relval,
-					unsigned long flags,
-					unsigned long *persistent);
+extern unsigned long bfin_get_addr_from_rp (u32 *ptr, u32 relval,
+					u32 flags, u32 *persistent);
 
-extern void bfin_put_addr_at_rp(unsigned long *ptr, unsigned long addr,
-		                unsigned long relval);
+extern void bfin_put_addr_at_rp(u32 *ptr, u32 addr, u32 relval);
 
 /* The amount by which a relocation can exceed the program image limits
    without being regarded as an error.  */
 
 #define	flat_reloc_valid(reloc, size)	((reloc) <= (size))
 
-#define	flat_get_addr_from_rp(rp, relval, flags, persistent)	\
-	bfin_get_addr_from_rp(rp, relval, flags, persistent)
-#define	flat_put_addr_at_rp(rp, val, relval)	\
-	bfin_put_addr_at_rp(rp, val, relval)
+static inline int flat_get_addr_from_rp(u32 __user *rp, u32 relval, u32 flags,
+					u32 *addr, u32 *persistent)
+{
+	*addr = bfin_get_addr_from_rp(rp, relval, flags, persistent);
+	return 0;
+}
+
+static inline int flat_put_addr_at_rp(u32 __user *rp, u32 val, u32 relval)
+{
+	bfin_put_addr_at_rp(rp, val, relval);
+	return 0;
+}
 
 /* Convert a relocation entry into an address.  */
 static inline unsigned long
diff --git a/arch/blackfin/kernel/flat.c b/arch/blackfin/kernel/flat.c
index b5b6584..d29ab6a 100644
--- a/arch/blackfin/kernel/flat.c
+++ b/arch/blackfin/kernel/flat.c
@@ -13,14 +13,14 @@
 #define FLAT_BFIN_RELOC_TYPE_16H_BIT 1
 #define FLAT_BFIN_RELOC_TYPE_32_BIT 2
 
-unsigned long bfin_get_addr_from_rp(unsigned long *ptr,
-		unsigned long relval,
-		unsigned long flags,
-		unsigned long *persistent)
+unsigned long bfin_get_addr_from_rp(u32 *ptr,
+		u32 relval,
+		u32 flags,
+		u32 *persistent)
 {
 	unsigned short *usptr = (unsigned short *)ptr;
 	int type = (relval >> 26) & 7;
-	unsigned long val;
+	u32 val;
 
 	switch (type) {
 	case FLAT_BFIN_RELOC_TYPE_16_BIT:
@@ -59,8 +59,7 @@ EXPORT_SYMBOL(bfin_get_addr_from_rp);
  * Insert the address ADDR into the symbol reference at RP;
  * RELVAL is the raw relocation-table entry from which RP is derived
  */
-void bfin_put_addr_at_rp(unsigned long *ptr, unsigned long addr,
-		unsigned long relval)
+void bfin_put_addr_at_rp(u32 *ptr, u32 addr, u32 relval)
 {
 	unsigned short *usptr = (unsigned short *)ptr;
 	int type = (relval >> 26) & 7;