17 files changed, 370 insertions, 170 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 947d3e2ed5c2..9d5b78aad4c5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1099,8 +1099,6 @@ config PROVE_LOCKING
         select DEBUG_MUTEXES
         select DEBUG_RT_MUTEXES if RT_MUTEXES
         select DEBUG_LOCK_ALLOC
-        select LOCKDEP_CROSSRELEASE
-        select LOCKDEP_COMPLETIONS
         select TRACE_IRQFLAGS
         default n
         help
@@ -1170,37 +1168,6 @@ config LOCK_STAT
          CONFIG_LOCK_STAT defines "contended" and "acquired" lock events.
          (CONFIG_LOCKDEP defines "acquire" and "release" events.)
 
-config LOCKDEP_CROSSRELEASE
-        bool
-        help
-         This makes lockdep work for crosslock which is a lock allowed to
-         be released in a different context from the acquisition context.
-         Normally a lock must be released in the context acquiring the lock.
-         However, relexing this constraint helps synchronization primitives
-         such as page locks or completions can use the lock correctness
-         detector, lockdep.
-
-config LOCKDEP_COMPLETIONS
-        bool
-        help
-         A deadlock caused by wait_for_completion() and complete() can be
-         detected by lockdep using crossrelease feature.
-
-config BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK
-        bool "Enable the boot parameter, crossrelease_fullstack"
-        depends on LOCKDEP_CROSSRELEASE
-        default n
-        help
-         The lockdep "cross-release" feature needs to record stack traces
-         (of calling functions) for all acquisitions, for eventual later
-         use during analysis. By default only a single caller is recorded,
-         because the unwind operation can be very expensive with deeper
-         stack chains.
-
-         However a boot parameter, crossrelease_fullstack, was
-         introduced since sometimes deeper traces are required for full
-         analysis. This option turns on the boot parameter.
-
 config DEBUG_LOCKDEP
         bool "Lock dependency engine debugging"
         depends on DEBUG_KERNEL && LOCKDEP
diff --git a/lib/ashldi3.c b/lib/ashldi3.c
index 1b6087db95a5..3ffc46e3bb6c 100644
--- a/lib/ashldi3.c
+++ b/lib/ashldi3.c
@@ -16,7 +16,7 @@
 
 #include <linux/export.h>
 
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 long long notrace __ashldi3(long long u, word_type b)
 {
diff --git a/lib/ashrdi3.c b/lib/ashrdi3.c
index 2e67c97ac65a..ea054550f0e8 100644
--- a/lib/ashrdi3.c
+++ b/lib/ashrdi3.c
@@ -16,7 +16,7 @@
 
 #include <linux/export.h>
 
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 long long notrace __ashrdi3(long long u, word_type b)
 {
diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c
index 1ef0cec38d78..dc14beae2c9a 100644
--- a/lib/asn1_decoder.c
+++ b/lib/asn1_decoder.c
@@ -313,42 +313,47 @@ next_op:
 
         /* Decide how to handle the operation */
         switch (op) {
-        case ASN1_OP_MATCH_ANY_ACT:
-        case ASN1_OP_MATCH_ANY_ACT_OR_SKIP:
-        case ASN1_OP_COND_MATCH_ANY_ACT:
-        case ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP:
-                ret = actions[machine[pc + 1]](context, hdr, tag, data + dp, len);
-                if (ret < 0)
-                        return ret;
-                goto skip_data;
-
-        case ASN1_OP_MATCH_ACT:
-        case ASN1_OP_MATCH_ACT_OR_SKIP:
-        case ASN1_OP_COND_MATCH_ACT_OR_SKIP:
-                ret = actions[machine[pc + 2]](context, hdr, tag, data + dp, len);
-                if (ret < 0)
-                        return ret;
-                goto skip_data;
-
         case ASN1_OP_MATCH:
         case ASN1_OP_MATCH_OR_SKIP:
+        case ASN1_OP_MATCH_ACT:
+        case ASN1_OP_MATCH_ACT_OR_SKIP:
         case ASN1_OP_MATCH_ANY:
         case ASN1_OP_MATCH_ANY_OR_SKIP:
+        case ASN1_OP_MATCH_ANY_ACT:
+        case ASN1_OP_MATCH_ANY_ACT_OR_SKIP:
         case ASN1_OP_COND_MATCH_OR_SKIP:
+        case ASN1_OP_COND_MATCH_ACT_OR_SKIP:
         case ASN1_OP_COND_MATCH_ANY:
         case ASN1_OP_COND_MATCH_ANY_OR_SKIP:
-        skip_data:
+        case ASN1_OP_COND_MATCH_ANY_ACT:
+        case ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP:
+
                 if (!(flags & FLAG_CONS)) {
                         if (flags & FLAG_INDEFINITE_LENGTH) {
+                                size_t tmp = dp;
+
                                 ret = asn1_find_indefinite_length(
-                                        data, datalen, &dp, &len, &errmsg);
+                                        data, datalen, &tmp, &len, &errmsg);
                                 if (ret < 0)
                                         goto error;
-                        } else {
-                                dp += len;
                         }
                         pr_debug("- LEAF: %zu\n", len);
                 }
+
+                if (op & ASN1_OP_MATCH__ACT) {
+                        unsigned char act;
+
+                        if (op & ASN1_OP_MATCH__ANY)
+                                act = machine[pc + 1];
+                        else
+                                act = machine[pc + 2];
+                        ret = actions[act](context, hdr, tag, data + dp, len);
+                        if (ret < 0)
+                                return ret;
+                }
+
+                if (!(flags & FLAG_CONS))
+                        dp += len;
                 pc += asn1_op_lengths[op];
                 goto next_op;
 
@@ -434,6 +439,8 @@ next_op:
                         else
                                 act = machine[pc + 1];
                         ret = actions[act](context, hdr, 0, data + tdp, len);
+                        if (ret < 0)
+                                return ret;
                 }
                 pc += asn1_op_lengths[op];
                 goto next_op;
diff --git a/lib/cmpdi2.c b/lib/cmpdi2.c
index 6d7ebf6c2b86..2250da7e503e 100644
--- a/lib/cmpdi2.c
+++ b/lib/cmpdi2.c
@@ -16,7 +16,7 @@
 
 #include <linux/export.h>
 
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 word_type notrace __cmpdi2(long long a, long long b)
 {
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index c3e84edc47c9..2615074d3de5 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -346,7 +346,8 @@ static int kobject_uevent_net_broadcast(struct kobject *kobj,
 static void zap_modalias_env(struct kobj_uevent_env *env)
 {
         static const char modalias_prefix[] = "MODALIAS=";
-        int i;
+        size_t len;
+        int i, j;
 
         for (i = 0; i < env->envp_idx;) {
                 if (strncmp(env->envp[i], modalias_prefix,
@@ -355,11 +356,18 @@ static void zap_modalias_env(struct kobj_uevent_env *env)
                         continue;
                 }
 
-                if (i != env->envp_idx - 1)
-                        memmove(&env->envp[i], &env->envp[i + 1],
-                                sizeof(env->envp[i]) * env->envp_idx - 1);
+                len = strlen(env->envp[i]) + 1;
+
+                if (i != env->envp_idx - 1) {
+                        memmove(env->envp[i], env->envp[i + 1],
+                                env->buflen - len);
+
+                        for (j = i; j < env->envp_idx - 1; j++)
+                                env->envp[j] = env->envp[j + 1] - len;
+                }
 
                 env->envp_idx--;
+                env->buflen -= len;
         }
 }
 
diff --git a/lib/lshrdi3.c b/lib/lshrdi3.c
index 8e845f4bb65f..99cfa5721f2d 100644
--- a/lib/lshrdi3.c
+++ b/lib/lshrdi3.c
@@ -17,7 +17,7 @@
  */
 
 #include <linux/module.h>
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 long long notrace __lshrdi3(long long u, word_type b)
 {
diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
index 57fd45ab7af1..08c60d10747f 100644
--- a/lib/mpi/longlong.h
+++ b/lib/mpi/longlong.h
@@ -671,7 +671,23 @@ do {						\
         **************  MIPS/64  **************
         ***************************************/
 #if (defined(__mips) && __mips >= 3) && W_TYPE_SIZE == 64
-#if (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4)
+#if defined(__mips_isa_rev) && __mips_isa_rev >= 6
+/*
+ * GCC ends up emitting a __multi3 intrinsic call for MIPS64r6 with the plain C
+ * code below, so we special case MIPS64r6 until the compiler can do better.
+ */
+#define umul_ppmm(w1, w0, u, v)                                         \
+do {                                                                    \
+        __asm__ ("dmulu %0,%1,%2"                                       \
+                 : "=d" ((UDItype)(w0))                                 \
+                 : "d" ((UDItype)(u)),                                  \
+                   "d" ((UDItype)(v)));                                 \
+        __asm__ ("dmuhu %0,%1,%2"                                       \
+                 : "=d" ((UDItype)(w1))                                 \
+                 : "d" ((UDItype)(u)),                                  \
+                   "d" ((UDItype)(v)));                                 \
+} while (0)
+#elif (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4)
 #define umul_ppmm(w1, w0, u, v) \
 do {                                                                    \
         typedef unsigned int __ll_UTItype __attribute__((mode(TI)));    \
diff --git a/lib/muldi3.c b/lib/muldi3.c
index 88938543e10a..54c8b3123376 100644
--- a/lib/muldi3.c
+++ b/lib/muldi3.c
@@ -15,7 +15,7 @@
  */
 
 #include <linux/export.h>
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 #define W_TYPE_SIZE 32
 
diff --git a/lib/nlattr.c b/lib/nlattr.c
index 8bf78b4b78f0..dfa55c873c13 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -15,7 +15,11 @@
 #include <linux/types.h>
 #include <net/netlink.h>
 
-/* for these data types attribute length must be exactly given size */
+/* For these data types, attribute length should be exactly the given
+ * size. However, to maintain compatibility with broken commands, if the
+ * attribute length does not match the expected size a warning is emitted
+ * to the user that the command is sending invalid data and needs to be fixed.
+ */
 static const u8 nla_attr_len[NLA_TYPE_MAX+1] = {
         [NLA_U8]        = sizeof(u8),
         [NLA_U16]       = sizeof(u16),
@@ -28,8 +32,16 @@ static const u8 nla_attr_len[NLA_TYPE_MAX+1] = {
 };
 
 static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = {
+        [NLA_U8]        = sizeof(u8),
+        [NLA_U16]       = sizeof(u16),
+        [NLA_U32]       = sizeof(u32),
+        [NLA_U64]       = sizeof(u64),
         [NLA_MSECS]     = sizeof(u64),
         [NLA_NESTED]    = NLA_HDRLEN,
+        [NLA_S8]        = sizeof(s8),
+        [NLA_S16]       = sizeof(s16),
+        [NLA_S32]       = sizeof(s32),
+        [NLA_S64]       = sizeof(s64),
 };
 
 static int validate_nla_bitfield32(const struct nlattr *nla,
@@ -69,11 +81,9 @@ static int validate_nla(const struct nlattr *nla, int maxtype,
 
         BUG_ON(pt->type > NLA_TYPE_MAX);
 
-        /* for data types NLA_U* and NLA_S* require exact length */
-        if (nla_attr_len[pt->type]) {
-                if (attrlen != nla_attr_len[pt->type])
-                        return -ERANGE;
-                return 0;
+        if (nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) {
+                pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
+                                    current->comm, type);
         }
 
         switch (pt->type) {
diff --git a/lib/oid_registry.c b/lib/oid_registry.c
index 41b9e50711a7..0bcac6ccb1b2 100644
--- a/lib/oid_registry.c
+++ b/lib/oid_registry.c
@@ -116,14 +116,14 @@ int sprint_oid(const void *data, size_t datasize, char *buffer, size_t bufsize)
         int count;
 
         if (v >= end)
-                return -EBADMSG;
+                goto bad;
 
         n = *v++;
         ret = count = snprintf(buffer, bufsize, "%u.%u", n / 40, n % 40);
+        if (count >= bufsize)
+                return -ENOBUFS;
         buffer += count;
         bufsize -= count;
-        if (bufsize == 0)
-                return -ENOBUFS;
 
         while (v < end) {
                 num = 0;
@@ -134,20 +134,24 @@ int sprint_oid(const void *data, size_t datasize, char *buffer, size_t bufsize)
                         num = n & 0x7f;
                         do {
                                 if (v >= end)
-                                        return -EBADMSG;
+                                        goto bad;
                                 n = *v++;
                                 num <<= 7;
                                 num |= n & 0x7f;
                         } while (n & 0x80);
                 }
                 ret += count = snprintf(buffer, bufsize, ".%lu", num);
-                buffer += count;
-                if (bufsize <= count)
+                if (count >= bufsize)
                         return -ENOBUFS;
+                buffer += count;
                 bufsize -= count;
         }
 
         return ret;
+
+bad:
+        snprintf(buffer, bufsize, "(bad)");
+        return -EBADMSG;
 }
 EXPORT_SYMBOL_GPL(sprint_oid);
 
diff --git a/lib/rbtree.c b/lib/rbtree.c
index ba4a9d165f1b..d3ff682fd4b8 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -603,6 +603,16 @@ void rb_replace_node(struct rb_node *victim, struct rb_node *new,
 }
 EXPORT_SYMBOL(rb_replace_node);
 
+void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new,
+                            struct rb_root_cached *root)
+{
+        rb_replace_node(victim, new, &root->rb_root);
+
+        if (root->rb_leftmost == victim)
+                root->rb_leftmost = new;
+}
+EXPORT_SYMBOL(rb_replace_node_cached);
+
 void rb_replace_node_rcu(struct rb_node *victim, struct rb_node *new,
                          struct rb_root *root)
 {
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index aa8812ae6776..f369889e521d 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -435,6 +435,41 @@ loop:
         return 0;
 }
 
+static int bpf_fill_ld_abs_vlan_push_pop2(struct bpf_test *self)
+{
+        struct bpf_insn *insn;
+
+        insn = kmalloc_array(16, sizeof(*insn), GFP_KERNEL);
+        if (!insn)
+                return -ENOMEM;
+
+        /* Due to func address being non-const, we need to
+         * assemble this here.
+         */
+        insn[0] = BPF_MOV64_REG(R6, R1);
+        insn[1] = BPF_LD_ABS(BPF_B, 0);
+        insn[2] = BPF_LD_ABS(BPF_H, 0);
+        insn[3] = BPF_LD_ABS(BPF_W, 0);
+        insn[4] = BPF_MOV64_REG(R7, R6);
+        insn[5] = BPF_MOV64_IMM(R6, 0);
+        insn[6] = BPF_MOV64_REG(R1, R7);
+        insn[7] = BPF_MOV64_IMM(R2, 1);
+        insn[8] = BPF_MOV64_IMM(R3, 2);
+        insn[9] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+                               bpf_skb_vlan_push_proto.func - __bpf_call_base);
+        insn[10] = BPF_MOV64_REG(R6, R7);
+        insn[11] = BPF_LD_ABS(BPF_B, 0);
+        insn[12] = BPF_LD_ABS(BPF_H, 0);
+        insn[13] = BPF_LD_ABS(BPF_W, 0);
+        insn[14] = BPF_MOV64_IMM(R0, 42);
+        insn[15] = BPF_EXIT_INSN();
+
+        self->u.ptr.insns = insn;
+        self->u.ptr.len = 16;
+
+        return 0;
+}
+
 static int bpf_fill_jump_around_ld_abs(struct bpf_test *self)
 {
         unsigned int len = BPF_MAXINSNS;
@@ -6066,6 +6101,14 @@ static struct bpf_test tests[] = {
                 {},
                 { {0x1, 0x42 } },
         },
+        {
+                "LD_ABS with helper changing skb data",
+                { },
+                INTERNAL,
+                { 0x34 },
+                { { ETH_HLEN, 42 } },
+                .fill_helper = bpf_fill_ld_abs_vlan_push_pop2,
+        },
 };
 
 static struct net_device dev;
@@ -6207,9 +6250,8 @@ static struct bpf_prog *generate_filter(int which, int *err)
                                 return NULL;
                         }
                 }
-                /* We don't expect to fail. */
                 if (*err) {
-                        pr_cont("FAIL to attach err=%d len=%d\n",
+                        pr_cont("FAIL to prog_create err=%d len=%d\n",
                                 *err, fprog.len);
                         return NULL;
                 }
@@ -6233,6 +6275,10 @@ static struct bpf_prog *generate_filter(int which, int *err)
                  * checks.
                  */
                 fp = bpf_prog_select_runtime(fp, err);
+                if (*err) {
+                        pr_cont("FAIL to select_runtime err=%d\n", *err);
+                        return NULL;
+                }
                 break;
         }
 
@@ -6418,8 +6464,8 @@ static __init int test_bpf(void)
                                 pass_cnt++;
                                 continue;
                         }
-
-                        return err;
+                        err_cnt++;
+                        continue;
                 }
 
                 pr_cont("jited:%u ", fp->jited);
diff --git a/lib/test_printf.c b/lib/test_printf.c
index 563f10e6876a..71ebfa43ad05 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -24,24 +24,6 @@
 #define PAD_SIZE 16
 #define FILL_CHAR '$'
 
-#define PTR1 ((void*)0x01234567)
-#define PTR2 ((void*)(long)(int)0xfedcba98)
-
-#if BITS_PER_LONG == 64
-#define PTR1_ZEROES "000000000"
-#define PTR1_SPACES "         "
-#define PTR1_STR "1234567"
-#define PTR2_STR "fffffffffedcba98"
-#define PTR_WIDTH 16
-#else
-#define PTR1_ZEROES "0"
-#define PTR1_SPACES " "
-#define PTR1_STR "1234567"
-#define PTR2_STR "fedcba98"
-#define PTR_WIDTH 8
-#endif
-#define PTR_WIDTH_STR stringify(PTR_WIDTH)
-
 static unsigned total_tests __initdata;
 static unsigned failed_tests __initdata;
 static char *test_buffer __initdata;
@@ -217,30 +199,79 @@ test_string(void)
         test("a  |   |   ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c");
 }
 
+#define PLAIN_BUF_SIZE 64       /* leave some space so we don't oops */
+
+#if BITS_PER_LONG == 64
+
+#define PTR_WIDTH 16
+#define PTR ((void *)0xffff0123456789ab)
+#define PTR_STR "ffff0123456789ab"
+#define ZEROS "00000000"        /* hex 32 zero bits */
+
+static int __init
+plain_format(void)
+{
+        char buf[PLAIN_BUF_SIZE];
+        int nchars;
+
+        nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR);
+
+        if (nchars != PTR_WIDTH || strncmp(buf, ZEROS, strlen(ZEROS)) != 0)
+                return -1;
+
+        return 0;
+}
+
+#else
+
+#define PTR_WIDTH 8
+#define PTR ((void *)0x456789ab)
+#define PTR_STR "456789ab"
+
+static int __init
+plain_format(void)
+{
+        /* Format is implicitly tested for 32 bit machines by plain_hash() */
+        return 0;
+}
+
+#endif  /* BITS_PER_LONG == 64 */
+
+static int __init
+plain_hash(void)
+{
+        char buf[PLAIN_BUF_SIZE];
+        int nchars;
+
+        nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR);
+
+        if (nchars != PTR_WIDTH || strncmp(buf, PTR_STR, PTR_WIDTH) == 0)
+                return -1;
+
+        return 0;
+}
+
+/*
+ * We can't use test() to test %p because we don't know what output to expect
+ * after an address is hashed.
+ */
 static void __init
 plain(void)
 {
-        test(PTR1_ZEROES PTR1_STR " " PTR2_STR, "%p %p", PTR1, PTR2);
-        /*
-         * The field width is overloaded for some %p extensions to
-         * pass another piece of information. For plain pointers, the
-         * behaviour is slightly odd: One cannot pass either the 0
-         * flag nor a precision to %p without gcc complaining, and if
-         * one explicitly gives a field width, the number is no longer
-         * zero-padded.
-         */
-        test("|" PTR1_STR PTR1_SPACES "  |  " PTR1_SPACES PTR1_STR "|",
-             "|%-*p|%*p|", PTR_WIDTH+2, PTR1, PTR_WIDTH+2, PTR1);
-        test("|" PTR2_STR "  |  " PTR2_STR "|",
-             "|%-*p|%*p|", PTR_WIDTH+2, PTR2, PTR_WIDTH+2, PTR2);
+        int err;
 
-        /*
-         * Unrecognized %p extensions are treated as plain %p, but the
-         * alphanumeric suffix is ignored (that is, does not occur in
-         * the output.)
-         */
-        test("|"PTR1_ZEROES PTR1_STR"|", "|%p0y|", PTR1);
-        test("|"PTR2_STR"|", "|%p0y|", PTR2);
+        err = plain_hash();
+        if (err) {
+                pr_warn("plain 'p' does not appear to be hashed\n");
+                failed_tests++;
+                return;
+        }
+
+        err = plain_format();
+        if (err) {
+                pr_warn("hashing plain 'p' has unexpected format\n");
+                failed_tests++;
+        }
 }
 
 static void __init
@@ -251,6 +282,7 @@ symbol_ptr(void)
 static void __init
 kernel_ptr(void)
 {
+        /* We can't test this without access to kptr_restrict. */
 }
 
 static void __init
diff --git a/lib/timerqueue.c b/lib/timerqueue.c
index 4a720ed4fdaf..0d54bcbc8170 100644
--- a/lib/timerqueue.c
+++ b/lib/timerqueue.c
@@ -33,8 +33,9 @@
  * @head: head of timerqueue
  * @node: timer node to be added
  *
- * Adds the timer node to the timerqueue, sorted by the
- * node's expires value.
+ * Adds the timer node to the timerqueue, sorted by the node's expires
+ * value. Returns true if the newly added timer is the first expiring timer in
+ * the queue.
  */
 bool timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node)
 {
@@ -70,7 +71,8 @@ EXPORT_SYMBOL_GPL(timerqueue_add);
  * @head: head of timerqueue
  * @node: timer node to be removed
  *
- * Removes the timer node from the timerqueue.
+ * Removes the timer node from the timerqueue. Returns true if the queue is
+ * not empty after the remove.
  */
 bool timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node)
 {
diff --git a/lib/ucmpdi2.c b/lib/ucmpdi2.c
index 49a53505c8e3..25ca2d4c1e19 100644
--- a/lib/ucmpdi2.c
+++ b/lib/ucmpdi2.c
@@ -15,7 +15,7 @@
  */
 
 #include <linux/module.h>
-#include <lib/libgcc.h>
+#include <linux/libgcc.h>
 
 word_type __ucmpdi2(unsigned long long a, unsigned long long b)
 {
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 1746bae94d41..01c3957b2de6 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -33,6 +33,8 @@
 #include <linux/uuid.h>
 #include <linux/of.h>
 #include <net/addrconf.h>
+#include <linux/siphash.h>
+#include <linux/compiler.h>
 #ifdef CONFIG_BLOCK
 #include <linux/blkdev.h>
 #endif
@@ -1343,6 +1345,59 @@ char *uuid_string(char *buf, char *end, const u8 *addr,
         return string(buf, end, uuid, spec);
 }
 
+int kptr_restrict __read_mostly;
+
+static noinline_for_stack
+char *restricted_pointer(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;
+        }
+
+        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())
+                        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 number(buf, end, (unsigned long)ptr, spec);
+}
+
 static noinline_for_stack
 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
 {
@@ -1591,7 +1646,86 @@ char *device_node_string(char *buf, char *end, struct device_node *dn,
         return widen_string(buf, buf - buf_start, end, spec);
 }
 
-int kptr_restrict __read_mostly;
+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);
+}
+
+static bool have_filled_random_ptr_key __read_mostly;
+static siphash_key_t ptr_key __read_mostly;
+
+static void fill_random_ptr_key(struct random_ready_callback *unused)
+{
+        get_random_bytes(&ptr_key, sizeof(ptr_key));
+        /*
+         * have_filled_random_ptr_key==true is dependent on get_random_bytes().
+         * ptr_to_id() needs to see have_filled_random_ptr_key==true
+         * after get_random_bytes() returns.
+         */
+        smp_mb();
+        WRITE_ONCE(have_filled_random_ptr_key, true);
+}
+
+static struct random_ready_callback random_ready = {
+        .func = fill_random_ptr_key
+};
+
+static int __init initialize_ptr_random(void)
+{
+        int ret = add_random_ready_callback(&random_ready);
+
+        if (!ret) {
+                return 0;
+        } else if (ret == -EALREADY) {
+                fill_random_ptr_key(&random_ready);
+                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)
+{
+        unsigned long hashval;
+        const int default_width = 2 * sizeof(ptr);
+
+        if (unlikely(!have_filled_random_ptr_key)) {
+                spec.field_width = default_width;
+                /* string length must be less than default_width */
+                return string(buf, end, "(ptrval)", 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
+
+        spec.flags |= SMALL;
+        if (spec.field_width == -1) {
+                spec.field_width = default_width;
+                spec.flags |= ZEROPAD;
+        }
+        spec.base = 16;
+
+        return number(buf, end, hashval, spec);
+}
 
 /*
  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
@@ -1698,11 +1832,16 @@ int kptr_restrict __read_mostly;
  *                        c major compatible string
  *                        C full compatible string
  *
+ * - 'x' For printing the address. Equivalent to "%lx".
+ *
  * ** Please update also Documentation/printk-formats.txt when making changes **
  *
  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
  * function pointers are really function descriptors, which contain a
  * pointer to the real address.
+ *
+ * Note: The default behaviour (unadorned %p) is to hash the address,
+ * rendering it useful as a unique identifier.
  */
 static noinline_for_stack
 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
@@ -1792,47 +1931,9 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
                         return buf;
                 }
         case 'K':
-                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 = default_width;
-                                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;
+                if (!kptr_restrict)
                         break;
-                }
-                break;
-
+                return restricted_pointer(buf, end, ptr, spec);
         case 'N':
                 return netdev_bits(buf, end, ptr, fmt);
         case 'a':
@@ -1857,15 +1958,12 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
                 case 'F':
                         return device_node_string(buf, end, ptr, spec, fmt + 1);
                 }
+        case 'x':
+                return pointer_string(buf, end, ptr, spec);
         }
-        spec.flags |= SMALL;
-        if (spec.field_width == -1) {
-                spec.field_width = default_width;
-                spec.flags |= ZEROPAD;
-        }
-        spec.base = 16;
 
-        return number(buf, end, (unsigned long) ptr, spec);
+        /* default is to _not_ leak addresses, hash before printing */
+        return ptr_to_id(buf, end, ptr, spec);
 }
 
 /*