s390/seccomp: fix error return for filtered system calls

commit dc295880c6752076f8b94ba3885d0bfff09e3e82 upstream.

The syscall_set_return_value function of s390 negates the error argument
before storing the value to the return register gpr2. This is incorrect,
the seccomp code already passes the negative error value.
Store the unmodified error value to gpr2.

Signed-off-by: Jan Willeke <willeke@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index cd29d2f4e4f355512ecbafd0cfcc0c7fab05042a..749313b452ae604c9a4c106845f8ec5c667aa81f 100644 (file)
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -54,7 +54,7 @@ static inline void syscall_set_return_value(struct task_struct *task,
                                            struct pt_regs *regs,
                                            int error, long val)
 {
-       regs->gprs[2] = error ? -error : val;
+       regs->gprs[2] = error ? error : val;
 }
 
 static inline void syscall_get_arguments(struct task_struct *task,