sigframe: Use blkset from ctl

When constructing sigframe for parasite, we my use ctl's blkset,
not the CoreEntry's one. This simplifies further patching.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/cr-restore.c

@@ -2934,6 +2934,7 @@ static int sigreturn_restore(pid_t pid, struct task_restore_args *task_args, uns
 	for (i = 0; i < current->nr_threads; i++) {
 		CoreEntry *tcore;
 		struct rt_sigframe *sigframe;
+		k_rtsigset_t *blkset = NULL;
 
 		thread_args[i].pid = current->threads[i].virt;
 		thread_args[i].siginfo_n = siginfo_priv_nr[i];
@@ -2945,8 +2946,12 @@ static int sigreturn_restore(pid_t pid, struct task_restore_args *task_args, uns
 		if (thread_args[i].pid == pid) {
 			task_args->t = thread_args + i;
 			tcore = core;
-		} else
+			blkset = (void *)&tcore->tc->blk_sigset;
+		} else {
 			tcore = current->core[i];
+			if (tcore->thread_core->has_blk_sigset)
+				blkset = (void *)&tcore->thread_core->blk_sigset;
+		}
 
 		if ((tcore->tc || tcore->ids) && thread_args[i].pid != pid) {
 			pr_err("Thread has optional fields present %d\n",
@@ -2983,7 +2988,7 @@ static int sigreturn_restore(pid_t pid, struct task_restore_args *task_args, uns
 		thread_args[i].mz = mz + i;
 		sigframe = (struct rt_sigframe *)&mz[i].rt_sigframe;
 
-		if (construct_sigframe(sigframe, sigframe, tcore))
+		if (construct_sigframe(sigframe, sigframe, blkset, tcore))
 			goto err;
 
 		if (thread_args[i].pid != pid)

criu/include/sigframe.h

@@ -52,6 +52,7 @@ struct rt_ucontext {
 
 extern int construct_sigframe(struct rt_sigframe *sigframe,
 			      struct rt_sigframe *rsigframe,
+			      k_rtsigset_t *blkset,
 			      CoreEntry *core);
 
 #endif /* __CR_SIGFRAME_H__ */

criu/parasite-syscall.c

@@ -1347,7 +1347,7 @@ static int parasite_start_daemon(struct parasite_ctl *ctl, struct pstree_item *i
 		return -1;
 	}
 
-	if (construct_sigframe(ctl->sigframe, ctl->rsigframe, item->core[0]))
+	if (construct_sigframe(ctl->sigframe, ctl->rsigframe, &ctl->orig.sigmask, item->core[0]))
 		return -1;
 
 	if (parasite_init_daemon(ctl, dmpi(item)->netns))

criu/sigframe.c

@@ -23,6 +23,7 @@ static inline void setup_sas(struct rt_sigframe* sigframe, ThreadSasEntry *sas)
 
 int construct_sigframe(struct rt_sigframe *sigframe,
 				     struct rt_sigframe *rsigframe,
+				     k_rtsigset_t *blkset,
 				     CoreEntry *core)
 {
 	k_rtsigset_t *blk_sigset = RT_SIGFRAME_UC_SIGMASK(sigframe);
@@ -30,12 +31,9 @@ int construct_sigframe(struct rt_sigframe *sigframe,
 	if (restore_gpregs(sigframe, CORE_THREAD_ARCH_INFO(core)->gpregs))
 		return -1;
 
-	if (core->tc)
-		memcpy(blk_sigset, &core->tc->blk_sigset, sizeof(k_rtsigset_t));
-	else if (core->thread_core->has_blk_sigset) {
-		memcpy(blk_sigset,
-			&core->thread_core->blk_sigset, sizeof(k_rtsigset_t));
-	} else
+	if (blkset)
+		memcpy(blk_sigset, blkset, sizeof(k_rtsigset_t));
+	else
 		memset(blk_sigset, 0, sizeof(k_rtsigset_t));
 
 	if (restore_fpu(sigframe, core))