Fix the arm sys_sigreturn(): its argument is a struct ucontext, not a

struct sigframe containing the struct ucontext.

The signal trampoline return code on the other hand DOES have just a
struct sigframe on the stack to work with, so have it get a pointer to
the ucontext out of there to pass along to sys_sigreturn.

In other words, make everything work right whether sys_sigreturn is
invoked from the trampoline or from userland code calling sigreturn(2).

Submitted by:	Takashi Komatsu <komatsu.taka@jp.panasonic.com>
Reviewed by:	cognet

3 files changed, 8 insertions, 7 deletions

diff --git a/sys/arm/arm/genassym.c b/sys/arm/arm/genassym.c
index 029529a..e38733b 100644
--- a/sys/arm/arm/genassym.c
+++ b/sys/arm/arm/genassym.c
@@ -109,6 +109,8 @@ ASSYM(TF_PC, offsetof(struct trapframe, tf_pc));
 ASSYM(P_PID, offsetof(struct proc, p_pid));
 ASSYM(P_FLAG, offsetof(struct proc, p_flag));
 
+ASSYM(SIGF_UC, offsetof(struct sigframe, sf_uc));
+
 #ifdef ARM_TP_ADDRESS
 ASSYM(ARM_TP_ADDRESS, ARM_TP_ADDRESS);
 ASSYM(ARM_RAS_START, ARM_RAS_START);
diff --git a/sys/arm/arm/locore.S b/sys/arm/arm/locore.S
index 364d19e..90eeeaf 100644
--- a/sys/arm/arm/locore.S
+++ b/sys/arm/arm/locore.S
@@ -557,6 +557,7 @@ END(abort)
 
 ENTRY_NP(sigcode)
 	mov	r0, sp
+	add	r0, r0, #SIGF_UC
 
 	/*
 	 * Call the sigreturn system call.
diff --git a/sys/arm/arm/machdep.c b/sys/arm/arm/machdep.c
index 68f4318..35f1432 100644
--- a/sys/arm/arm/machdep.c
+++ b/sys/arm/arm/machdep.c
@@ -742,28 +742,26 @@ sys_sigreturn(td, uap)
 		const struct __ucontext *sigcntxp;
 	} */ *uap;
 {
-	struct sigframe sf;
-	struct trapframe *tf;
+	ucontext_t uc;
 	int spsr;
 	
 	if (uap == NULL)
 		return (EFAULT);
-	if (copyin(uap->sigcntxp, &sf, sizeof(sf)))
+	if (copyin(uap->sigcntxp, &uc, sizeof(uc)))
 		return (EFAULT);
 	/*
 	 * Make sure the processor mode has not been tampered with and
 	 * interrupts have not been disabled.
 	 */
-	spsr = sf.sf_uc.uc_mcontext.__gregs[_REG_CPSR];
+	spsr = uc.uc_mcontext.__gregs[_REG_CPSR];
 	if ((spsr & PSR_MODE) != PSR_USR32_MODE ||
 	    (spsr & (I32_bit | F32_bit)) != 0)
 		return (EINVAL);
 		/* Restore register context. */
-	tf = td->td_frame;
-	set_mcontext(td, &sf.sf_uc.uc_mcontext);
+	set_mcontext(td, &uc.uc_mcontext);
 
 	/* Restore signal mask. */
-	kern_sigprocmask(td, SIG_SETMASK, &sf.sf_uc.uc_sigmask, NULL, 0);
+	kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
 
 	return (EJUSTRETURN);
 }