arm: simplify sigreturn decoding

* signal.c (sys_sigreturn) [ARM]: Do not define sigcontext and ucontext
structures, fetch signal mask only, use print_sigset_addr_len.

diff --git a/signal.c b/signal.c
index 3437f02d6187347414949996ce2b42477c1a2c68..bc78379cc96ec8f108f004957989b3c07a6e0841 100644 (file)
--- a/signal.c
+++ b/signal.c
@@ -692,49 +692,16 @@ sys_sigreturn(struct tcb *tcp)
 {
 #if defined(ARM)
        if (entering(tcp)) {
-               struct arm_sigcontext {
-                       unsigned long trap_no;
-                       unsigned long error_code;
-                       unsigned long oldmask;
-                       unsigned long arm_r0;
-                       unsigned long arm_r1;
-                       unsigned long arm_r2;
-                       unsigned long arm_r3;
-                       unsigned long arm_r4;
-                       unsigned long arm_r5;
-                       unsigned long arm_r6;
-                       unsigned long arm_r7;
-                       unsigned long arm_r8;
-                       unsigned long arm_r9;
-                       unsigned long arm_r10;
-                       unsigned long arm_fp;
-                       unsigned long arm_ip;
-                       unsigned long arm_sp;
-                       unsigned long arm_lr;
-                       unsigned long arm_pc;
-                       unsigned long arm_cpsr;
-                       unsigned long fault_address;
-               };
-               struct arm_ucontext {
-                       unsigned long uc_flags;
-                       unsigned long uc_link;  /* struct ucontext* */
-                       /* The next three members comprise stack_t struct: */
-                       unsigned long ss_sp;    /* void*   */
-                       unsigned long ss_flags; /* int     */
-                       unsigned long ss_size;  /* size_t  */
-                       struct arm_sigcontext sc;
-                       /* These two members are sigset_t: */
-                       unsigned long uc_sigmask[2];
-                       /* more fields follow, which we aren't interested in */
-               };
-               struct arm_ucontext uc;
-               if (umove(tcp, arm_regs.ARM_sp, &uc) < 0)
-                       return 0;
                /*
                 * Kernel fills out uc.sc.oldmask too when it sets up signal stack,
                 * but for sigmask restore, sigreturn syscall uses uc.uc_sigmask instead.
                 */
-               tprintsigmask_addr(") (mask ", uc.uc_sigmask);
+# define SIZEOF_STRUCT_SIGCONTEXT (21 * 4)
+# define OFFSETOF_STRUCT_UCONTEXT_UC_SIGMASK (5 * 4 + SIZEOF_STRUCT_SIGCONTEXT)
+               const long addr = arm_regs.ARM_sp +
+                       OFFSETOF_STRUCT_UCONTEXT_UC_SIGMASK;
+               tprints(") (mask ");
+               print_sigset_addr_len(tcp, addr, NSIG / 8);
        }
 #elif defined(S390) || defined(S390X)
        if (entering(tcp)) {