rst: Sanitize standard arrays remapping

On restore we have several arrays of objects that get remapped
into pie area and their number is also passed. Clean and shorten
the remapping code a bit and bing their naming to common format.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-restore.c

@@ -2860,29 +2860,21 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 	task_args->premmapped_addr = (unsigned long)rsti(current)->premmapped_addr;
 	task_args->premmapped_len = rsti(current)->premmapped_len;
 
-	task_args->nr_vmas = vmas->nr;
-	task_args->tgt_vmas = rst_mem_remap_ptr(tgt_vmas, RM_PRIVATE);
-
-	task_args->timer_n = posix_timers_nr;
-	task_args->posix_timers = rst_mem_remap_ptr(posix_timers_cpos, RM_PRIVATE);
-
-	task_args->timerfd_n = rst_timerfd_nr;
-	task_args->timerfd = rst_mem_remap_ptr(timerfd_mem_cpos, RM_PRIVATE);
-
-	task_args->siginfo_nr = siginfo_nr;
-	task_args->siginfo = rst_mem_remap_ptr(siginfo_cpos, RM_PRIVATE);
-
-	task_args->tcp_socks_nr = rst_tcp_socks_nr;
-	task_args->tcp_socks = rst_mem_remap_ptr(tcp_socks, RM_PRIVATE);
-
-	task_args->nr_rings = mm->n_aios;
-	task_args->rings = rst_mem_remap_ptr(aio_rings, RM_PRIVATE);
-
-	task_args->n_helpers = n_helpers;
-	if (n_helpers > 0)
-		task_args->helpers = rst_mem_remap_ptr(helpers_pos, RM_PRIVATE);
-	else
-		task_args->helpers = NULL;
+#define remap_array(name, nr, cpos)	do {				\
+		task_args->name##_n = nr;				\
+		task_args->name = rst_mem_remap_ptr(cpos, RM_PRIVATE);	\
+	} while (0)
+
+	remap_array(vmas,	  vmas->nr, tgt_vmas);
+	remap_array(posix_timers, posix_timers_nr, posix_timers_cpos);
+	remap_array(timerfd,	  rst_timerfd_nr, timerfd_mem_cpos);
+	remap_array(siginfo,	  siginfo_nr, siginfo_cpos);
+	remap_array(tcp_socks,	  rst_tcp_socks_nr, tcp_socks);
+	remap_array(rings,	  mm->n_aios, aio_rings);
+	remap_array(rlims,	  rlims_nr, rlims_cpos);
+	remap_array(helpers,	  n_helpers, helpers_pos);
+
+#undef remap_array
 
 	if (lsm) {
 		task_args->proc_attr_current = open_proc_rw(PROC_SELF, "attr/current");
@@ -2909,9 +2901,6 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 
 	strncpy(task_args->comm, core->tc->comm, sizeof(task_args->comm));
 
-	task_args->nr_rlim = rlims_nr;
-	if (rlims_nr)
-		task_args->rlims = rst_mem_remap_ptr(rlims_cpos, RM_PRIVATE);
 
 	/*
 	 * Fill up per-thread data.
@@ -2921,10 +2910,10 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 		struct rt_sigframe *sigframe;
 
 		thread_args[i].pid = current->threads[i].virt;
-		thread_args[i].siginfo_nr = siginfo_priv_nr[i];
+		thread_args[i].siginfo_n = siginfo_priv_nr[i];
 		thread_args[i].siginfo = rst_mem_remap_ptr(siginfo_cpos, RM_PRIVATE);
 		thread_args[i].siginfo += siginfo_nr;
-		siginfo_nr += thread_args[i].siginfo_nr;
+		siginfo_nr += thread_args[i].siginfo_n;
 
 		/* skip self */
 		if (thread_args[i].pid == pid) {

include/restorer.h

@@ -90,7 +90,8 @@ struct thread_restore_args {
 	tls_t				tls;
 
 	siginfo_t			*siginfo;
-	unsigned int			siginfo_nr;
+	unsigned int			siginfo_n;
+
 	int				pdeath_sig;
 } __aligned(64);
 
@@ -109,10 +110,33 @@ struct task_restore_args {
 	struct task_entries		*task_entries;
 	void				*rst_mem;
 	unsigned long			rst_mem_size;
-	VmaEntry			*tgt_vmas;
+
+	/* Below arrays get remapped from RM_PRIVATE in sigreturn_restore */
+	VmaEntry			*vmas;
+	unsigned int			vmas_n;
+
+	struct restore_posix_timer	*posix_timers;
+	unsigned int			posix_timers_n;
+
+	struct restore_timerfd		*timerfd;
+	unsigned int			timerfd_n;
+
 	siginfo_t			*siginfo;
-	unsigned int			siginfo_nr;
-	unsigned int			nr_vmas;
+	unsigned int			siginfo_n;
+
+	struct rst_tcp_sock		*tcp_socks;
+	unsigned int			tcp_socks_n;
+
+	struct rst_aio_ring		*rings;
+	unsigned int			rings_n;
+
+	struct rlimit			*rlims;
+	unsigned int			rlims_n;
+
+	pid_t				*helpers /* the TASK_HELPERS to wait on at the end of restore */;
+	unsigned int			helpers_n;
+	/* * * * * * * * * * * * * * * * * * * * */
+
 	unsigned long			premmapped_addr;
 	unsigned long			premmapped_len;
 	rt_sigaction_t			sigchld_act;
@@ -122,12 +146,6 @@ struct task_restore_args {
 
 	struct itimerval		itimers[3];
 
-	int				timer_n;
-	struct restore_posix_timer	*posix_timers;
-
-	int				timerfd_n;
-	struct restore_timerfd		*timerfd;
-
 	CredsEntry			creds;
 	u32				cap_inh[CR_CAP_SIZE];
 	u32				cap_prm[CR_CAP_SIZE];
@@ -140,20 +158,8 @@ struct task_restore_args {
 	u32				mm_saved_auxv_size;
 	char				comm[TASK_COMM_LEN];
 
-	int				nr_rlim;
-	struct rlimit			*rlims;
-
-	struct rst_tcp_sock		*tcp_socks;
-	int				tcp_socks_nr;
-
-	struct rst_aio_ring		*rings;
-	int				nr_rings;
-
 	int				fd_last_pid; /* sys.ns_last_pid for threads rst */
 
-	pid_t				*helpers /* the TASK_HELPERS to wait on at the end of restore */;
-	int				n_helpers;
-
 	int				proc_attr_current;
 	char				*lsm_profile;
 	int				lsm_profile_len;

pie/restorer.c

@@ -273,7 +273,7 @@ static void restore_rlims(struct task_restore_args *ta)
 {
 	int r;
 
-	for (r = 0; r < ta->nr_rlim; r++) {
+	for (r = 0; r < ta->rlims_n; r++) {
 		struct krlimit krlim;
 
 		krlim.rlim_cur = ta->rlims[r].rlim_cur;
@@ -378,7 +378,7 @@ long __export_restore_thread(struct thread_restore_args *args)
 
 	restore_finish_stage(CR_STATE_RESTORE);
 
-	if (restore_signals(args->siginfo, args->siginfo_nr, false))
+	if (restore_signals(args->siginfo, args->siginfo_n, false))
 		goto core_restore_end;
 
 	restore_finish_stage(CR_STATE_RESTORE_SIGCHLD);
@@ -469,7 +469,7 @@ static void rst_tcp_socks_all(struct task_restore_args *ta)
 {
 	int i;
 
-	for (i = 0; i < ta->tcp_socks_nr; i++)
+	for (i = 0; i < ta->tcp_socks_n; i++)
 		rst_tcp_repair_off(&ta->tcp_socks[i]);
 }
 
@@ -599,7 +599,7 @@ static int create_posix_timers(struct task_restore_args *args)
 	timer_t next_id;
 	struct sigevent sev;
 
-	for (i = 0; i < args->timer_n; i++) {
+	for (i = 0; i < args->posix_timers_n; i++) {
 		sev.sigev_notify = args->posix_timers[i].spt.it_sigev_notify;
 		sev.sigev_signo = args->posix_timers[i].spt.si_signo;
 		sev.sigev_value.sival_ptr = args->posix_timers[i].spt.sival_ptr;
@@ -635,7 +635,7 @@ static void restore_posix_timers(struct task_restore_args *args)
 	int i;
 	struct restore_posix_timer *rt;
 
-	for (i = 0; i < args->timer_n; i++) {
+	for (i = 0; i < args->posix_timers_n; i++) {
 		rt = &args->posix_timers[i];
 		sys_timer_settime((timer_t)rt->spt.it_id, 0, &rt->val, NULL);
 	}
@@ -719,7 +719,7 @@ static int wait_helpers(struct task_restore_args *task_args)
 {
 	int i;
 
-	for (i = 0; i < task_args->n_helpers; i++) {
+	for (i = 0; i < task_args->helpers_n; i++) {
 		int status;
 		pid_t pid = task_args->helpers[i];
 
@@ -787,7 +787,7 @@ long __export_restore_task(struct task_restore_args *args)
 
 	task_entries = args->task_entries;
 	helpers = args->helpers;
-	n_helpers = args->n_helpers;
+	n_helpers = args->helpers_n;
 	*args->breakpoint = rst_sigreturn;
 
 	ksigfillset(&act.rt_sa_mask);
@@ -811,8 +811,8 @@ long __export_restore_task(struct task_restore_args *args)
 		goto core_restore_end;
 
 	/* Shift private vma-s to the left */
-	for (i = 0; i < args->nr_vmas; i++) {
-		vma_entry = args->tgt_vmas + i;
+	for (i = 0; i < args->vmas_n; i++) {
+		vma_entry = args->vmas + i;
 
 		if (!vma_entry_is_private(vma_entry))
 			continue;
@@ -829,8 +829,8 @@ long __export_restore_task(struct task_restore_args *args)
 	}
 
 	/* Shift private vma-s to the right */
-	for (i = args->nr_vmas - 1; i >= 0; i--) {
-		vma_entry = args->tgt_vmas + i;
+	for (i = args->vmas_n - 1; i >= 0; i--) {
+		vma_entry = args->vmas + i;
 
 		if (!vma_entry_is_private(vma_entry))
 			continue;
@@ -849,8 +849,8 @@ long __export_restore_task(struct task_restore_args *args)
 	/*
 	 * OK, lets try to map new one.
 	 */
-	for (i = 0; i < args->nr_vmas; i++) {
-		vma_entry = args->tgt_vmas + i;
+	for (i = 0; i < args->vmas_n; i++) {
+		vma_entry = args->vmas + i;
 
 		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
 			continue;
@@ -870,12 +870,12 @@ long __export_restore_task(struct task_restore_args *args)
 	/*
 	 * Proxify vDSO.
 	 */
-	for (i = 0; i < args->nr_vmas; i++) {
-		if (vma_entry_is(&args->tgt_vmas[i], VMA_AREA_VDSO) ||
-		    vma_entry_is(&args->tgt_vmas[i], VMA_AREA_VVAR)) {
+	for (i = 0; i < args->vmas_n; i++) {
+		if (vma_entry_is(&args->vmas[i], VMA_AREA_VDSO) ||
+		    vma_entry_is(&args->vmas[i], VMA_AREA_VVAR)) {
 			if (vdso_proxify("dumpee", &args->vdso_sym_rt,
 					 args->vdso_rt_parked_at,
-					 i, args->tgt_vmas, args->nr_vmas))
+					 i, args->vmas, args->vmas_n))
 				goto core_restore_end;
 			break;
 		}
@@ -886,8 +886,8 @@ long __export_restore_task(struct task_restore_args *args)
 	 * Walk though all VMAs again to drop PROT_WRITE
 	 * if it was not there.
 	 */
-	for (i = 0; i < args->nr_vmas; i++) {
-		vma_entry = args->tgt_vmas + i;
+	for (i = 0; i < args->vmas_n; i++) {
+		vma_entry = args->vmas + i;
 
 		if (!(vma_entry_is(vma_entry, VMA_AREA_REGULAR)))
 			continue;
@@ -903,10 +903,10 @@ long __export_restore_task(struct task_restore_args *args)
 	/*
 	 * Finally restore madivse() bits
 	 */
-	for (i = 0; i < args->nr_vmas; i++) {
+	for (i = 0; i < args->vmas_n; i++) {
 		unsigned long m;
 
-		vma_entry = args->tgt_vmas + i;
+		vma_entry = args->vmas + i;
 		if (!vma_entry->has_madv || !vma_entry->madv)
 			continue;
 
@@ -932,7 +932,7 @@ long __export_restore_task(struct task_restore_args *args)
 	 * up AIO rings.
 	 */
 
-	for (i = 0; i < args->nr_rings; i++) {
+	for (i = 0; i < args->rings_n; i++) {
 		struct rst_aio_ring *raio = &args->rings[i];
 		unsigned long ctx = 0;
 		int ret;
@@ -1153,11 +1153,11 @@ long __export_restore_task(struct task_restore_args *args)
 
 	sys_sigaction(SIGCHLD, &args->sigchld_act, NULL, sizeof(k_rtsigset_t));
 
-	ret = restore_signals(args->siginfo, args->siginfo_nr, true);
+	ret = restore_signals(args->siginfo, args->siginfo_n, true);
 	if (ret)
 		goto core_restore_end;
 
-	ret = restore_signals(args->t->siginfo, args->t->siginfo_nr, false);
+	ret = restore_signals(args->t->siginfo, args->t->siginfo_n, false);
 	if (ret)
 		goto core_restore_end;