summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDiana Craciun <diana.craciun@nxp.com>2019-04-29 18:49:05 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-05-16 20:44:55 +0300
commit1a26467578d889fd8b6f42bb86ce264cd06d5859 (patch)
treebedb5030606051a823a7d616fd6f674995eff648
parent42b46e985c9901eeffd4e851b1c0e720ad18ef2e (diff)
downloadlinux-1a26467578d889fd8b6f42bb86ce264cd06d5859.tar.xz
powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms
commit c28218d4abbf4f2035495334d8bfcba64bda4787 upstream. Used barrier_nospec to sanitize the syscall table. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/powerpc/kernel/entry_32.S10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 3728e617e17e..609bc7d01f13 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -33,6 +33,7 @@
#include <asm/unistd.h>
#include <asm/ftrace.h>
#include <asm/ptrace.h>
+#include <asm/barrier.h>
/*
* MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
@@ -340,6 +341,15 @@ syscall_dotrace_cont:
ori r10,r10,sys_call_table@l
slwi r0,r0,2
bge- 66f
+
+ barrier_nospec_asm
+ /*
+ * Prevent the load of the handler below (based on the user-passed
+ * system call number) being speculatively executed until the test
+ * against NR_syscalls and branch to .66f above has
+ * committed.
+ */
+
lwzx r10,r10,r0 /* Fetch system call handler [ptr] */
mtlr r10
addi r9,r1,STACK_FRAME_OVERHEAD