sparc32: unaligned memory access (MNA) trap handler bug

Since commit f0e98c387e61de00646be31fab4c2fa0224e1efb ("[SPARC]: Fix
link errors with gcc-4.3") the MNA trap handler does not emulate
stores to unaligned addresses correctly. MNA operation from both
kernel and user space are affected.

A typical effect of this bug is nr_frags in skbs are overwritten
during buffer copying/checksum-calculation, or maximally 6 bytes
of data in the network buffer will be overwitten with garbage.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc/kernel/una_asm_32.S b/arch/sparc/kernel/una_asm_32.S
index 8cc0345..8f096e8 100644 (file)
--- a/arch/sparc/kernel/una_asm_32.S
+++ b/arch/sparc/kernel/una_asm_32.S
@@ -24,9 +24,9 @@ retl_efault:
        .globl  __do_int_store
 __do_int_store:
        ld      [%o2], %g1
-       cmp     %1, 2
+       cmp     %o1, 2
        be      2f
-        cmp    %1, 4
+        cmp    %o1, 4
        be      1f
         srl    %g1, 24, %g2
        srl     %g1, 16, %g7