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

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

From: Marcin Nowakowski <marcin.nowakow...@imgtec.com>

commit 74f1077b5b783e7bf4fa3007cefdc8dbd6c07518 upstream.

Currently regs_return_value always negates reg[2] if it determines
the syscall has failed, but when called in kernel context this check is
invalid and may result in returning a wrong value.

This fixes errors reported by CONFIG_KPROBES_SANITY_TEST

Fixes: d7e7528bcd45 ("Audit: push audit success and retcode into arch ptrace.h")
Signed-off-by: Marcin Nowakowski <marcin.nowakow...@imgtec.com>
Cc: linux-m...@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14381/
Signed-off-by: Ralf Baechle <r...@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/mips/include/asm/ptrace.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/include/asm/ptrace.h
+++ b/arch/mips/include/asm/ptrace.h
@@ -152,7 +152,7 @@ static inline int is_syscall_success(str
 
 static inline long regs_return_value(struct pt_regs *regs)
 {
-       if (is_syscall_success(regs))
+       if (is_syscall_success(regs) || !user_mode(regs))
                return regs->regs[2];
        else
                return -regs->regs[2];


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