diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 812e59e..e78017a 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/lib/vsprintf.c
  *
@@ -17,6 +18,7 @@
  */
 
 #include <stdarg.h>
+#include <linux/build_bug.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
@@ -30,6 +32,7 @@
 #include <linux/ioport.h>
 #include <linux/dcache.h>
 #include <linux/cred.h>
+#include <linux/rtc.h>
 #include <linux/uuid.h>
 #include <linux/of.h>
 #include <net/addrconf.h>
@@ -404,6 +407,8 @@
 	unsigned int	base:8;		/* number base, 8, 10 or 16 only */
 	signed int	precision:16;	/* # of digits/chars */
 } __packed;
+static_assert(sizeof(struct printf_spec) == 8);
+
 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
 #define PRECISION_MAX ((1 << 15) - 1)
 
@@ -421,8 +426,6 @@
 	int field_width = spec.field_width;
 	int precision = spec.precision;
 
-	BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
-
 	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
 	 * produces same digits or (maybe lowercased) letters */
 	locase = (spec.flags & SMALL);
@@ -591,14 +594,12 @@
 	return buf;
 }
 
-static noinline_for_stack
-char *string(char *buf, char *end, const char *s, struct printf_spec spec)
+/* Handle string from a well known address. */
+static char *string_nocheck(char *buf, char *end, const char *s,
+			    struct printf_spec spec)
 {
 	int len = 0;
-	size_t lim = spec.precision;
-
-	if ((unsigned long)s < PAGE_SIZE)
-		s = "(null)";
+	int lim = spec.precision;
 
 	while (lim--) {
 		char c = *s++;
@@ -612,6 +613,213 @@
 	return widen_string(buf, len, end, spec);
 }
 
+/* Be careful: error messages must fit into the given buffer. */
+static char *error_string(char *buf, char *end, const char *s,
+			  struct printf_spec spec)
+{
+	/*
+	 * Hard limit to avoid a completely insane messages. It actually
+	 * works pretty well because most error messages are in
+	 * the many pointer format modifiers.
+	 */
+	if (spec.precision == -1)
+		spec.precision = 2 * sizeof(void *);
+
+	return string_nocheck(buf, end, s, spec);
+}
+
+/*
+ * Do not call any complex external code here. Nested printk()/vsprintf()
+ * might cause infinite loops. Failures might break printk() and would
+ * be hard to debug.
+ */
+static const char *check_pointer_msg(const void *ptr)
+{
+	if (!ptr)
+		return "(null)";
+
+	if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
+		return "(efault)";
+
+	return NULL;
+}
+
+static int check_pointer(char **buf, char *end, const void *ptr,
+			 struct printf_spec spec)
+{
+	const char *err_msg;
+
+	err_msg = check_pointer_msg(ptr);
+	if (err_msg) {
+		*buf = error_string(*buf, end, err_msg, spec);
+		return -EFAULT;
+	}
+
+	return 0;
+}
+
+static noinline_for_stack
+char *string(char *buf, char *end, const char *s,
+	     struct printf_spec spec)
+{
+	if (check_pointer(&buf, end, s, spec))
+		return buf;
+
+	return string_nocheck(buf, end, s, spec);
+}
+
+static char *pointer_string(char *buf, char *end,
+			    const void *ptr,
+			    struct printf_spec spec)
+{
+	spec.base = 16;
+	spec.flags |= SMALL;
+	if (spec.field_width == -1) {
+		spec.field_width = 2 * sizeof(ptr);
+		spec.flags |= ZEROPAD;
+	}
+
+	return number(buf, end, (unsigned long int)ptr, spec);
+}
+
+/* Make pointers available for printing early in the boot sequence. */
+static int debug_boot_weak_hash __ro_after_init;
+
+static int __init debug_boot_weak_hash_enable(char *str)
+{
+	debug_boot_weak_hash = 1;
+	pr_info("debug_boot_weak_hash enabled\n");
+	return 0;
+}
+early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
+
+static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
+static siphash_key_t ptr_key __read_mostly;
+
+static void enable_ptr_key_workfn(struct work_struct *work)
+{
+	get_random_bytes(&ptr_key, sizeof(ptr_key));
+	/* Needs to run from preemptible context */
+	static_branch_disable(&not_filled_random_ptr_key);
+}
+
+static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
+
+static void fill_random_ptr_key(struct random_ready_callback *unused)
+{
+	/* This may be in an interrupt handler. */
+	queue_work(system_unbound_wq, &enable_ptr_key_work);
+}
+
+static struct random_ready_callback random_ready = {
+	.func = fill_random_ptr_key
+};
+
+static int __init initialize_ptr_random(void)
+{
+	int key_size = sizeof(ptr_key);
+	int ret;
+
+	/* Use hw RNG if available. */
+	if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
+		static_branch_disable(&not_filled_random_ptr_key);
+		return 0;
+	}
+
+	ret = add_random_ready_callback(&random_ready);
+	if (!ret) {
+		return 0;
+	} else if (ret == -EALREADY) {
+		/* This is in preemptible context */
+		enable_ptr_key_workfn(&enable_ptr_key_work);
+		return 0;
+	}
+
+	return ret;
+}
+early_initcall(initialize_ptr_random);
+
+/* Maps a pointer to a 32 bit unique identifier. */
+static char *ptr_to_id(char *buf, char *end, const void *ptr,
+		       struct printf_spec spec)
+{
+	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
+	unsigned long hashval;
+
+	/* When debugging early boot use non-cryptographically secure hash. */
+	if (unlikely(debug_boot_weak_hash)) {
+		hashval = hash_long((unsigned long)ptr, 32);
+		return pointer_string(buf, end, (const void *)hashval, spec);
+	}
+
+	if (static_branch_unlikely(&not_filled_random_ptr_key)) {
+		spec.field_width = 2 * sizeof(ptr);
+		/* string length must be less than default_width */
+		return error_string(buf, end, str, spec);
+	}
+
+#ifdef CONFIG_64BIT
+	hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
+	/*
+	 * Mask off the first 32 bits, this makes explicit that we have
+	 * modified the address (and 32 bits is plenty for a unique ID).
+	 */
+	hashval = hashval & 0xffffffff;
+#else
+	hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
+#endif
+	return pointer_string(buf, end, (const void *)hashval, spec);
+}
+
+int kptr_restrict __read_mostly;
+
+static noinline_for_stack
+char *restricted_pointer(char *buf, char *end, const void *ptr,
+			 struct printf_spec spec)
+{
+	switch (kptr_restrict) {
+	case 0:
+		/* Handle as %p, hash and do _not_ leak addresses. */
+		return ptr_to_id(buf, end, ptr, spec);
+	case 1: {
+		const struct cred *cred;
+
+		/*
+		 * kptr_restrict==1 cannot be used in IRQ context
+		 * because its test for CAP_SYSLOG would be meaningless.
+		 */
+		if (in_irq() || in_serving_softirq() || in_nmi()) {
+			if (spec.field_width == -1)
+				spec.field_width = 2 * sizeof(ptr);
+			return error_string(buf, end, "pK-error", spec);
+		}
+
+		/*
+		 * Only print the real pointer value if the current
+		 * process has CAP_SYSLOG and is running with the
+		 * same credentials it started with. This is because
+		 * access to files is checked at open() time, but %pK
+		 * checks permission at read() time. We don't want to
+		 * leak pointer values if a binary opens a file using
+		 * %pK and then elevates privileges before reading it.
+		 */
+		cred = current_cred();
+		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
+		    !uid_eq(cred->euid, cred->uid) ||
+		    !gid_eq(cred->egid, cred->gid))
+			ptr = NULL;
+		break;
+	}
+	case 2:
+	default:
+		/* Always print 0's for %pK */
+		ptr = NULL;
+		break;
+	}
+
+	return pointer_string(buf, end, ptr, spec);
+}
+
 static noinline_for_stack
 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 		  const char *fmt)
@@ -631,6 +839,11 @@
 
 	rcu_read_lock();
 	for (i = 0; i < depth; i++, d = p) {
+		if (check_pointer(&buf, end, d, spec)) {
+			rcu_read_unlock();
+			return buf;
+		}
+
 		p = READ_ONCE(d->d_parent);
 		array[i] = READ_ONCE(d->d_name.name);
 		if (p == d) {
@@ -656,13 +869,26 @@
 	return widen_string(buf, n, end, spec);
 }
 
+static noinline_for_stack
+char *file_dentry_name(char *buf, char *end, const struct file *f,
+			struct printf_spec spec, const char *fmt)
+{
+	if (check_pointer(&buf, end, f, spec))
+		return buf;
+
+	return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
+}
 #ifdef CONFIG_BLOCK
 static noinline_for_stack
 char *bdev_name(char *buf, char *end, struct block_device *bdev,
 		struct printf_spec spec, const char *fmt)
 {
-	struct gendisk *hd = bdev->bd_disk;
-	
+	struct gendisk *hd;
+
+	if (check_pointer(&buf, end, bdev, spec))
+		return buf;
+
+	hd = bdev->bd_disk;
 	buf = string(buf, end, hd->disk_name, spec);
 	if (bdev->bd_part->partno) {
 		if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
@@ -697,7 +923,7 @@
 	else
 		sprint_symbol_no_offset(sym, value);
 
-	return string(buf, end, sym, spec);
+	return string_nocheck(buf, end, sym, spec);
 #else
 	return special_hex_number(buf, end, value, sizeof(void *));
 #endif
@@ -719,6 +945,20 @@
 	.precision = -1,
 };
 
+static const struct printf_spec default_dec02_spec = {
+	.base = 10,
+	.field_width = 2,
+	.precision = -1,
+	.flags = ZEROPAD,
+};
+
+static const struct printf_spec default_dec04_spec = {
+	.base = 10,
+	.field_width = 4,
+	.precision = -1,
+	.flags = ZEROPAD,
+};
+
 static noinline_for_stack
 char *resource_string(char *buf, char *end, struct resource *res,
 		      struct printf_spec spec, const char *fmt)
@@ -767,29 +1007,32 @@
 	int decode = (fmt[0] == 'R') ? 1 : 0;
 	const struct printf_spec *specp;
 
+	if (check_pointer(&buf, end, res, spec))
+		return buf;
+
 	*p++ = '[';
 	if (res->flags & IORESOURCE_IO) {
-		p = string(p, pend, "io  ", str_spec);
+		p = string_nocheck(p, pend, "io  ", str_spec);
 		specp = &io_spec;
 	} else if (res->flags & IORESOURCE_MEM) {
-		p = string(p, pend, "mem ", str_spec);
+		p = string_nocheck(p, pend, "mem ", str_spec);
 		specp = &mem_spec;
 	} else if (res->flags & IORESOURCE_IRQ) {
-		p = string(p, pend, "irq ", str_spec);
+		p = string_nocheck(p, pend, "irq ", str_spec);
 		specp = &default_dec_spec;
 	} else if (res->flags & IORESOURCE_DMA) {
-		p = string(p, pend, "dma ", str_spec);
+		p = string_nocheck(p, pend, "dma ", str_spec);
 		specp = &default_dec_spec;
 	} else if (res->flags & IORESOURCE_BUS) {
-		p = string(p, pend, "bus ", str_spec);
+		p = string_nocheck(p, pend, "bus ", str_spec);
 		specp = &bus_spec;
 	} else {
-		p = string(p, pend, "??? ", str_spec);
+		p = string_nocheck(p, pend, "??? ", str_spec);
 		specp = &mem_spec;
 		decode = 0;
 	}
 	if (decode && res->flags & IORESOURCE_UNSET) {
-		p = string(p, pend, "size ", str_spec);
+		p = string_nocheck(p, pend, "size ", str_spec);
 		p = number(p, pend, resource_size(res), *specp);
 	} else {
 		p = number(p, pend, res->start, *specp);
@@ -800,21 +1043,21 @@
 	}
 	if (decode) {
 		if (res->flags & IORESOURCE_MEM_64)
-			p = string(p, pend, " 64bit", str_spec);
+			p = string_nocheck(p, pend, " 64bit", str_spec);
 		if (res->flags & IORESOURCE_PREFETCH)
-			p = string(p, pend, " pref", str_spec);
+			p = string_nocheck(p, pend, " pref", str_spec);
 		if (res->flags & IORESOURCE_WINDOW)
-			p = string(p, pend, " window", str_spec);
+			p = string_nocheck(p, pend, " window", str_spec);
 		if (res->flags & IORESOURCE_DISABLED)
-			p = string(p, pend, " disabled", str_spec);
+			p = string_nocheck(p, pend, " disabled", str_spec);
 	} else {
-		p = string(p, pend, " flags ", str_spec);
+		p = string_nocheck(p, pend, " flags ", str_spec);
 		p = number(p, pend, res->flags, default_flag_spec);
 	}
 	*p++ = ']';
 	*p = '\0';
 
-	return string(buf, end, sym, spec);
+	return string_nocheck(buf, end, sym, spec);
 }
 
 static noinline_for_stack
@@ -829,9 +1072,8 @@
 		/* nothing to print */
 		return buf;
 
-	if (ZERO_OR_NULL_PTR(addr))
-		/* NULL pointer */
-		return string(buf, end, NULL, spec);
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
 
 	switch (fmt[1]) {
 	case 'C':
@@ -878,6 +1120,9 @@
 	int i, chunksz;
 	bool first = true;
 
+	if (check_pointer(&buf, end, bitmap, spec))
+		return buf;
+
 	/* reused to print numbers */
 	spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
 
@@ -919,6 +1164,9 @@
 	int cur, rbot, rtop;
 	bool first = true;
 
+	if (check_pointer(&buf, end, bitmap, spec))
+		return buf;
+
 	rbot = cur = find_first_bit(bitmap, nr_bits);
 	while (cur < nr_bits) {
 		rtop = cur;
@@ -957,6 +1205,9 @@
 	char separator;
 	bool reversed = false;
 
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
+
 	switch (fmt[1]) {
 	case 'F':
 		separator = '-';
@@ -982,7 +1233,7 @@
 	}
 	*p = '\0';
 
-	return string(buf, end, mac_addr, spec);
+	return string_nocheck(buf, end, mac_addr, spec);
 }
 
 static noinline_for_stack
@@ -1145,7 +1396,7 @@
 	else
 		ip6_string(ip6_addr, addr, fmt);
 
-	return string(buf, end, ip6_addr, spec);
+	return string_nocheck(buf, end, ip6_addr, spec);
 }
 
 static noinline_for_stack
@@ -1156,7 +1407,7 @@
 
 	ip4_string(ip4_addr, addr, fmt);
 
-	return string(buf, end, ip4_addr, spec);
+	return string_nocheck(buf, end, ip4_addr, spec);
 }
 
 static noinline_for_stack
@@ -1218,7 +1469,7 @@
 	}
 	*p = '\0';
 
-	return string(buf, end, ip6_addr, spec);
+	return string_nocheck(buf, end, ip6_addr, spec);
 }
 
 static noinline_for_stack
@@ -1253,7 +1504,42 @@
 	}
 	*p = '\0';
 
-	return string(buf, end, ip4_addr, spec);
+	return string_nocheck(buf, end, ip4_addr, spec);
+}
+
+static noinline_for_stack
+char *ip_addr_string(char *buf, char *end, const void *ptr,
+		     struct printf_spec spec, const char *fmt)
+{
+	char *err_fmt_msg;
+
+	if (check_pointer(&buf, end, ptr, spec))
+		return buf;
+
+	switch (fmt[1]) {
+	case '6':
+		return ip6_addr_string(buf, end, ptr, spec, fmt);
+	case '4':
+		return ip4_addr_string(buf, end, ptr, spec, fmt);
+	case 'S': {
+		const union {
+			struct sockaddr		raw;
+			struct sockaddr_in	v4;
+			struct sockaddr_in6	v6;
+		} *sa = ptr;
+
+		switch (sa->raw.sa_family) {
+		case AF_INET:
+			return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
+		case AF_INET6:
+			return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
+		default:
+			return error_string(buf, end, "(einval)", spec);
+		}}
+	}
+
+	err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
+	return error_string(buf, end, err_fmt_msg, spec);
 }
 
 static noinline_for_stack
@@ -1268,9 +1554,8 @@
 	if (spec.field_width == 0)
 		return buf;				/* nothing to print */
 
-	if (ZERO_OR_NULL_PTR(addr))
-		return string(buf, end, NULL, spec);	/* NULL pointer */
-
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
 
 	do {
 		switch (fmt[count++]) {
@@ -1316,6 +1601,21 @@
 	return buf;
 }
 
+static char *va_format(char *buf, char *end, struct va_format *va_fmt,
+		       struct printf_spec spec, const char *fmt)
+{
+	va_list va;
+
+	if (check_pointer(&buf, end, va_fmt, spec))
+		return buf;
+
+	va_copy(va, *va_fmt->va);
+	buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
+	va_end(va);
+
+	return buf;
+}
+
 static noinline_for_stack
 char *uuid_string(char *buf, char *end, const u8 *addr,
 		  struct printf_spec spec, const char *fmt)
@@ -1326,6 +1626,9 @@
 	const u8 *index = uuid_index;
 	bool uc = false;
 
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
+
 	switch (*(++fmt)) {
 	case 'L':
 		uc = true;		/* fall-through */
@@ -1354,98 +1657,41 @@
 
 	*p = 0;
 
-	return string(buf, end, uuid, spec);
+	return string_nocheck(buf, end, uuid, spec);
 }
 
 static noinline_for_stack
-char *pointer_string(char *buf, char *end, const void *ptr,
-		     struct printf_spec spec)
-{
-	spec.base = 16;
-	spec.flags |= SMALL;
-	if (spec.field_width == -1) {
-		spec.field_width = 2 * sizeof(ptr);
-		spec.flags |= ZEROPAD;
-	}
-
-	return number(buf, end, (unsigned long int)ptr, spec);
-}
-
-int kptr_restrict __read_mostly;
-
-static noinline_for_stack
-char *restricted_pointer(char *buf, char *end, const void *ptr,
-			 struct printf_spec spec)
-{
-	switch (kptr_restrict) {
-	case 0:
-		/* Always print %pK values */
-		break;
-	case 1: {
-		const struct cred *cred;
-
-		/*
-		 * kptr_restrict==1 cannot be used in IRQ context
-		 * because its test for CAP_SYSLOG would be meaningless.
-		 */
-		if (in_irq() || in_serving_softirq() || in_nmi()) {
-			if (spec.field_width == -1)
-				spec.field_width = 2 * sizeof(ptr);
-			return string(buf, end, "pK-error", spec);
-		}
-
-		/*
-		 * Only print the real pointer value if the current
-		 * process has CAP_SYSLOG and is running with the
-		 * same credentials it started with. This is because
-		 * access to files is checked at open() time, but %pK
-		 * checks permission at read() time. We don't want to
-		 * leak pointer values if a binary opens a file using
-		 * %pK and then elevates privileges before reading it.
-		 */
-		cred = current_cred();
-		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
-		    !uid_eq(cred->euid, cred->uid) ||
-		    !gid_eq(cred->egid, cred->gid))
-			ptr = NULL;
-		break;
-	}
-	case 2:
-	default:
-		/* Always print 0's for %pK */
-		ptr = NULL;
-		break;
-	}
-
-	return pointer_string(buf, end, ptr, spec);
-}
-
-static noinline_for_stack
-char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
+char *netdev_bits(char *buf, char *end, const void *addr,
+		  struct printf_spec spec,  const char *fmt)
 {
 	unsigned long long num;
 	int size;
 
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
+
 	switch (fmt[1]) {
 	case 'F':
 		num = *(const netdev_features_t *)addr;
 		size = sizeof(netdev_features_t);
 		break;
 	default:
-		num = (unsigned long)addr;
-		size = sizeof(unsigned long);
-		break;
+		return error_string(buf, end, "(%pN?)", spec);
 	}
 
 	return special_hex_number(buf, end, num, size);
 }
 
 static noinline_for_stack
-char *address_val(char *buf, char *end, const void *addr, const char *fmt)
+char *address_val(char *buf, char *end, const void *addr,
+		  struct printf_spec spec, const char *fmt)
 {
 	unsigned long long num;
 	int size;
 
+	if (check_pointer(&buf, end, addr, spec))
+		return buf;
+
 	switch (fmt[1]) {
 	case 'd':
 		num = *(const dma_addr_t *)addr;
@@ -1462,11 +1708,99 @@
 }
 
 static noinline_for_stack
+char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
+{
+	int year = tm->tm_year + (r ? 0 : 1900);
+	int mon = tm->tm_mon + (r ? 0 : 1);
+
+	buf = number(buf, end, year, default_dec04_spec);
+	if (buf < end)
+		*buf = '-';
+	buf++;
+
+	buf = number(buf, end, mon, default_dec02_spec);
+	if (buf < end)
+		*buf = '-';
+	buf++;
+
+	return number(buf, end, tm->tm_mday, default_dec02_spec);
+}
+
+static noinline_for_stack
+char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
+{
+	buf = number(buf, end, tm->tm_hour, default_dec02_spec);
+	if (buf < end)
+		*buf = ':';
+	buf++;
+
+	buf = number(buf, end, tm->tm_min, default_dec02_spec);
+	if (buf < end)
+		*buf = ':';
+	buf++;
+
+	return number(buf, end, tm->tm_sec, default_dec02_spec);
+}
+
+static noinline_for_stack
+char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
+	      struct printf_spec spec, const char *fmt)
+{
+	bool have_t = true, have_d = true;
+	bool raw = false;
+	int count = 2;
+
+	if (check_pointer(&buf, end, tm, spec))
+		return buf;
+
+	switch (fmt[count]) {
+	case 'd':
+		have_t = false;
+		count++;
+		break;
+	case 't':
+		have_d = false;
+		count++;
+		break;
+	}
+
+	raw = fmt[count] == 'r';
+
+	if (have_d)
+		buf = date_str(buf, end, tm, raw);
+	if (have_d && have_t) {
+		/* Respect ISO 8601 */
+		if (buf < end)
+			*buf = 'T';
+		buf++;
+	}
+	if (have_t)
+		buf = time_str(buf, end, tm, raw);
+
+	return buf;
+}
+
+static noinline_for_stack
+char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
+		    const char *fmt)
+{
+	switch (fmt[1]) {
+	case 'R':
+		return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
+	default:
+		return error_string(buf, end, "(%ptR?)", spec);
+	}
+}
+
+static noinline_for_stack
 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
 	    const char *fmt)
 {
-	if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
-		return string(buf, end, NULL, spec);
+	if (!IS_ENABLED(CONFIG_HAVE_CLK))
+		return error_string(buf, end, "(%pC?)", spec);
+
+	if (check_pointer(&buf, end, clk, spec))
+		return buf;
 
 	switch (fmt[1]) {
 	case 'n':
@@ -1474,7 +1808,7 @@
 #ifdef CONFIG_COMMON_CLK
 		return string(buf, end, __clk_get_name(clk), spec);
 #else
-		return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
+		return ptr_to_id(buf, end, clk, spec);
 #endif
 	}
 }
@@ -1507,11 +1841,15 @@
 }
 
 static noinline_for_stack
-char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
+char *flags_string(char *buf, char *end, void *flags_ptr,
+		   struct printf_spec spec, const char *fmt)
 {
 	unsigned long flags;
 	const struct trace_print_flags *names;
 
+	if (check_pointer(&buf, end, flags_ptr, spec))
+		return buf;
+
 	switch (fmt[1]) {
 	case 'p':
 		flags = *(unsigned long *)flags_ptr;
@@ -1528,8 +1866,7 @@
 		names = gfpflag_names;
 		break;
 	default:
-		WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
-		return buf;
+		return error_string(buf, end, "(%pG?)", spec);
 	}
 
 	return format_flags(buf, end, flags, names);
@@ -1551,13 +1888,13 @@
 
 	/* special case for root node */
 	if (!parent)
-		return string(buf, end, "/", default_str_spec);
+		return string_nocheck(buf, end, "/", default_str_spec);
 
 	for (depth = 0; parent->parent; depth++)
 		parent = parent->parent;
 
 	for ( ; depth >= 0; depth--) {
-		buf = string(buf, end, "/", default_str_spec);
+		buf = string_nocheck(buf, end, "/", default_str_spec);
 		buf = string(buf, end, device_node_name_for_depth(np, depth),
 			     default_str_spec);
 	}
@@ -1585,10 +1922,10 @@
 	str_spec.field_width = -1;
 
 	if (!IS_ENABLED(CONFIG_OF))
-		return string(buf, end, "(!OF)", spec);
+		return error_string(buf, end, "(%pOF?)", spec);
 
-	if ((unsigned long)dn < PAGE_SIZE)
-		return string(buf, end, "(null)", spec);
+	if (check_pointer(&buf, end, dn, spec))
+		return buf;
 
 	/* simple case without anything any more format specifiers */
 	fmt++;
@@ -1596,6 +1933,7 @@
 		fmt = "f";
 
 	for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
+		int precision;
 		if (pass) {
 			if (buf < end)
 				*buf = ':';
@@ -1607,7 +1945,11 @@
 			buf = device_node_gen_full_name(dn, buf, end);
 			break;
 		case 'n':	/* name */
-			buf = string(buf, end, dn->name, str_spec);
+			p = kbasename(of_node_full_name(dn));
+			precision = str_spec.precision;
+			str_spec.precision = strchrnul(p, '@') - p;
+			buf = string(buf, end, p, str_spec);
+			str_spec.precision = precision;
 			break;
 		case 'p':	/* phandle */
 			buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
@@ -1624,7 +1966,7 @@
 			tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
 			tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
 			tbuf[4] = 0;
-			buf = string(buf, end, tbuf, str_spec);
+			buf = string_nocheck(buf, end, tbuf, str_spec);
 			break;
 		case 'c':	/* major compatible string */
 			ret = of_property_read_string(dn, "compatible", &p);
@@ -1635,10 +1977,10 @@
 			has_mult = false;
 			of_property_for_each_string(dn, "compatible", prop, p) {
 				if (has_mult)
-					buf = string(buf, end, ",", str_spec);
-				buf = string(buf, end, "\"", str_spec);
+					buf = string_nocheck(buf, end, ",", str_spec);
+				buf = string_nocheck(buf, end, "\"", str_spec);
 				buf = string(buf, end, p, str_spec);
-				buf = string(buf, end, "\"", str_spec);
+				buf = string_nocheck(buf, end, "\"", str_spec);
 
 				has_mult = true;
 			}
@@ -1651,92 +1993,15 @@
 	return widen_string(buf, buf - buf_start, end, spec);
 }
 
-/* Make pointers available for printing early in the boot sequence. */
-static int debug_boot_weak_hash __ro_after_init;
-
-static int __init debug_boot_weak_hash_enable(char *str)
+static char *kobject_string(char *buf, char *end, void *ptr,
+			    struct printf_spec spec, const char *fmt)
 {
-	debug_boot_weak_hash = 1;
-	pr_info("debug_boot_weak_hash enabled\n");
-	return 0;
-}
-early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
-
-static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
-static siphash_key_t ptr_key __read_mostly;
-
-static void enable_ptr_key_workfn(struct work_struct *work)
-{
-	get_random_bytes(&ptr_key, sizeof(ptr_key));
-	/* Needs to run from preemptible context */
-	static_branch_disable(&not_filled_random_ptr_key);
-}
-
-static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
-
-static void fill_random_ptr_key(struct random_ready_callback *unused)
-{
-	/* This may be in an interrupt handler. */
-	queue_work(system_unbound_wq, &enable_ptr_key_work);
-}
-
-static struct random_ready_callback random_ready = {
-	.func = fill_random_ptr_key
-};
-
-static int __init initialize_ptr_random(void)
-{
-	int key_size = sizeof(ptr_key);
-	int ret;
-
-	/* Use hw RNG if available. */
-	if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
-		static_branch_disable(&not_filled_random_ptr_key);
-		return 0;
+	switch (fmt[1]) {
+	case 'F':
+		return device_node_string(buf, end, ptr, spec, fmt + 1);
 	}
 
-	ret = add_random_ready_callback(&random_ready);
-	if (!ret) {
-		return 0;
-	} else if (ret == -EALREADY) {
-		/* This is in preemptible context */
-		enable_ptr_key_workfn(&enable_ptr_key_work);
-		return 0;
-	}
-
-	return ret;
-}
-early_initcall(initialize_ptr_random);
-
-/* Maps a pointer to a 32 bit unique identifier. */
-static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
-{
-	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
-	unsigned long hashval;
-
-	/* When debugging early boot use non-cryptographically secure hash. */
-	if (unlikely(debug_boot_weak_hash)) {
-		hashval = hash_long((unsigned long)ptr, 32);
-		return pointer_string(buf, end, (const void *)hashval, spec);
-	}
-
-	if (static_branch_unlikely(&not_filled_random_ptr_key)) {
-		spec.field_width = 2 * sizeof(ptr);
-		/* string length must be less than default_width */
-		return string(buf, end, str, spec);
-	}
-
-#ifdef CONFIG_64BIT
-	hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
-	/*
-	 * Mask off the first 32 bits, this makes explicit that we have
-	 * modified the address (and 32 bits is plenty for a unique ID).
-	 */
-	hashval = hashval & 0xffffffff;
-#else
-	hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
-#endif
-	return pointer_string(buf, end, (const void *)hashval, spec);
+	return error_string(buf, end, "(%pO?)", spec);
 }
 
 /*
@@ -1823,27 +2088,26 @@
  * - 'd[234]' For a dentry name (optionally 2-4 last components)
  * - 'D[234]' Same as 'd' but for a struct file
  * - 'g' For block_device name (gendisk + partition number)
+ * - 't[R][dt][r]' For time and date as represented:
+ *      R    struct rtc_time
  * - 'C' For a clock, it prints the name (Common Clock Framework) or address
  *       (legacy clock framework) of the clock
  * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
  *        (legacy clock framework) of the clock
- * - 'Cr' For a clock, it prints the current rate of the clock
  * - 'G' For flags to be printed as a collection of symbolic strings that would
  *       construct the specific value. Supported flags given by option:
  *       p page flags (see struct page) given as pointer to unsigned long
  *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
  *       v vma flags (VM_*) given as pointer to unsigned long
- * - 'O' For a kobject based struct. Must be one of the following:
- *       - 'OF[fnpPcCF]'  For a device tree object
- *                        Without any optional arguments prints the full_name
- *                        f device node full_name
- *                        n device node name
- *                        p device node phandle
- *                        P device node path spec (name + @unit)
- *                        F device node flags
- *                        c major compatible string
- *                        C full compatible string
- *
+ * - 'OF[fnpPcCF]'  For a device tree object
+ *                  Without any optional arguments prints the full_name
+ *                  f device node full_name
+ *                  n device node name
+ *                  p device node phandle
+ *                  P device node path spec (name + @unit)
+ *                  F device node flags
+ *                  c major compatible string
+ *                  C full compatible string
  * - 'x' For printing the address. Equivalent to "%lx".
  *
  * ** When making changes please also update:
@@ -1856,18 +2120,6 @@
 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 	      struct printf_spec spec)
 {
-	const int default_width = 2 * sizeof(void *);
-
-	if (!ptr && *fmt != 'K' && *fmt != 'x') {
-		/*
-		 * Print (null) with the same width as a pointer so it makes
-		 * tabular output look nice.
-		 */
-		if (spec.field_width == -1)
-			spec.field_width = default_width;
-		return string(buf, end, "(null)", spec);
-	}
-
 	switch (*fmt) {
 	case 'F':
 	case 'f':
@@ -1903,71 +2155,36 @@
 					 * 4:	001.002.003.004
 					 * 6:   000102...0f
 					 */
-		switch (fmt[1]) {
-		case '6':
-			return ip6_addr_string(buf, end, ptr, spec, fmt);
-		case '4':
-			return ip4_addr_string(buf, end, ptr, spec, fmt);
-		case 'S': {
-			const union {
-				struct sockaddr		raw;
-				struct sockaddr_in	v4;
-				struct sockaddr_in6	v6;
-			} *sa = ptr;
-
-			switch (sa->raw.sa_family) {
-			case AF_INET:
-				return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
-			case AF_INET6:
-				return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
-			default:
-				return string(buf, end, "(invalid address)", spec);
-			}}
-		}
-		break;
+		return ip_addr_string(buf, end, ptr, spec, fmt);
 	case 'E':
 		return escaped_string(buf, end, ptr, spec, fmt);
 	case 'U':
 		return uuid_string(buf, end, ptr, spec, fmt);
 	case 'V':
-		{
-			va_list va;
-
-			va_copy(va, *((struct va_format *)ptr)->va);
-			buf += vsnprintf(buf, end > buf ? end - buf : 0,
-					 ((struct va_format *)ptr)->fmt, va);
-			va_end(va);
-			return buf;
-		}
+		return va_format(buf, end, ptr, spec, fmt);
 	case 'K':
-		if (!kptr_restrict)
-			break;
 		return restricted_pointer(buf, end, ptr, spec);
 	case 'N':
-		return netdev_bits(buf, end, ptr, fmt);
+		return netdev_bits(buf, end, ptr, spec, fmt);
 	case 'a':
-		return address_val(buf, end, ptr, fmt);
+		return address_val(buf, end, ptr, spec, fmt);
 	case 'd':
 		return dentry_name(buf, end, ptr, spec, fmt);
+	case 't':
+		return time_and_date(buf, end, ptr, spec, fmt);
 	case 'C':
 		return clock(buf, end, ptr, spec, fmt);
 	case 'D':
-		return dentry_name(buf, end,
-				   ((const struct file *)ptr)->f_path.dentry,
-				   spec, fmt);
+		return file_dentry_name(buf, end, ptr, spec, fmt);
 #ifdef CONFIG_BLOCK
 	case 'g':
 		return bdev_name(buf, end, ptr, spec, fmt);
 #endif
 
 	case 'G':
-		return flags_string(buf, end, ptr, fmt);
+		return flags_string(buf, end, ptr, spec, fmt);
 	case 'O':
-		switch (fmt[1]) {
-		case 'F':
-			return device_node_string(buf, end, ptr, spec, fmt + 1);
-		}
-		break;
+		return kobject_string(buf, end, ptr, spec, fmt);
 	case 'x':
 		return pointer_string(buf, end, ptr, spec);
 	}
@@ -2582,11 +2799,13 @@
 
 		case FORMAT_TYPE_STR: {
 			const char *save_str = va_arg(args, char *);
+			const char *err_msg;
 			size_t len;
 
-			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
-					|| (unsigned long)save_str < PAGE_SIZE)
-				save_str = "(null)";
+			err_msg = check_pointer_msg(save_str);
+			if (err_msg)
+				save_str = err_msg;
+
 			len = strlen(save_str) + 1;
 			if (str + len < end)
 				memcpy(str, save_str, len);