security: keys: Replace time_t/timespec with time64_t

The 'struct key' will use 'time_t' which we try to remove in the
kernel, since 'time_t' is not year 2038 safe on 32bit systems.
Also the 'struct keyring_search_context' will use 'timespec' type
to record current time, which is also not year 2038 safe on 32bit
systems.

Thus this patch replaces 'time_t' with 'time64_t' which is year 2038
safe for 'struct key', and replace 'timespec' with 'time64_t' for the
'struct keyring_search_context', since we only look at the the seconds
part of 'timespec' variable. Moreover we also change the codes where
using the 'time_t' and 'timespec', and we can get current time by
ktime_get_real_seconds() instead of current_kernel_time(), and use
'TIME64_MAX' macro to initialize the 'time64_t' type variable.

Especially in proc.c file, we have replaced 'unsigned long' and 'timespec'
type with 'u64' and 'time64_t' type to save the timeout value, which means
user will get one 'u64' type timeout value by issuing proc_keys_show()
function.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>

diff --git a/include/linux/key.h b/include/linux/key.h
index 8a15cab..e58ee10 100644 (file)
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -24,6 +24,7 @@
 #include <linux/atomic.h>
 #include <linux/assoc_array.h>
 #include <linux/refcount.h>
+#include <linux/time64.h>
 
 #ifdef __KERNEL__
 #include <linux/uidgid.h>
@@ -162,10 +163,10 @@ struct key {
        struct key_user         *user;          /* owner of this key */
        void                    *security;      /* security data for this key */
        union {
-               time_t          expiry;         /* time at which key expires (or 0) */
-               time_t          revoked_at;     /* time at which key was revoked */
+               time64_t        expiry;         /* time at which key expires (or 0) */
+               time64_t        revoked_at;     /* time at which key was revoked */
        };
-       time_t                  last_used_at;   /* last time used for LRU keyring discard */
+       time64_t                last_used_at;   /* last time used for LRU keyring discard */
        kuid_t                  uid;
        kgid_t                  gid;
        key_perm_t              perm;           /* access permissions */

diff --git a/security/keys/gc.c b/security/keys/gc.c
index afb3a91..6713fee 100644 (file)
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -32,7 +32,7 @@ DECLARE_WORK(key_gc_work, key_garbage_collector);
 static void key_gc_timer_func(unsigned long);
 static DEFINE_TIMER(key_gc_timer, key_gc_timer_func);
 
-static time_t key_gc_next_run = LONG_MAX;
+static time64_t key_gc_next_run = TIME64_MAX;
 static struct key_type *key_gc_dead_keytype;
 
 static unsigned long key_gc_flags;
@@ -53,12 +53,12 @@ struct key_type key_type_dead = {
  * Schedule a garbage collection run.
  * - time precision isn't particularly important
  */
-void key_schedule_gc(time_t gc_at)
+void key_schedule_gc(time64_t gc_at)
 {
        unsigned long expires;
-       time_t now = current_kernel_time().tv_sec;
+       time64_t now = ktime_get_real_seconds();
 
-       kenter("%ld", gc_at - now);
+       kenter("%lld", gc_at - now);
 
        if (gc_at <= now || test_bit(KEY_GC_REAP_KEYTYPE, &key_gc_flags)) {
                kdebug("IMMEDIATE");
@@ -87,7 +87,7 @@ void key_schedule_gc_links(void)
 static void key_gc_timer_func(unsigned long data)
 {
        kenter("");
-       key_gc_next_run = LONG_MAX;
+       key_gc_next_run = TIME64_MAX;
        key_schedule_gc_links();
 }
 
@@ -184,11 +184,11 @@ static void key_garbage_collector(struct work_struct *work)
 
        struct rb_node *cursor;
        struct key *key;
-       time_t new_timer, limit;
+       time64_t new_timer, limit;
 
        kenter("[%lx,%x]", key_gc_flags, gc_state);
 
-       limit = current_kernel_time().tv_sec;
+       limit = ktime_get_real_seconds();
        if (limit > key_gc_delay)
                limit -= key_gc_delay;
        else
@@ -204,7 +204,7 @@ static void key_garbage_collector(struct work_struct *work)
                gc_state |= KEY_GC_REAPING_DEAD_1;
        kdebug("new pass %x", gc_state);
 
-       new_timer = LONG_MAX;
+       new_timer = TIME64_MAX;
 
        /* As only this function is permitted to remove things from the key
         * serial tree, if cursor is non-NULL then it will always point to a
@@ -235,7 +235,7 @@ continue_scanning:
 
                if (gc_state & KEY_GC_SET_TIMER) {
                        if (key->expiry > limit && key->expiry < new_timer) {
-                               kdebug("will expire %x in %ld",
+                               kdebug("will expire %x in %lld",
                                       key_serial(key), key->expiry - limit);
                                new_timer = key->expiry;
                        }
@@ -276,7 +276,7 @@ maybe_resched:
         */
        kdebug("pass complete");
 
-       if (gc_state & KEY_GC_SET_TIMER && new_timer != (time_t)LONG_MAX) {
+       if (gc_state & KEY_GC_SET_TIMER && new_timer != (time64_t)TIME64_MAX) {
                new_timer += key_gc_delay;
                key_schedule_gc(new_timer);
        }

diff --git a/security/keys/internal.h b/security/keys/internal.h
index 503adba..9f8208d 100644 (file)
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -130,7 +130,7 @@ struct keyring_search_context {
        int                     skipped_ret;
        bool                    possessed;
        key_ref_t               result;
-       struct timespec         now;
+       time64_t                now;
 };
 
 extern bool key_default_cmp(const struct key *key,
@@ -169,10 +169,10 @@ extern void key_change_session_keyring(struct callback_head *twork);
 
 extern struct work_struct key_gc_work;
 extern unsigned key_gc_delay;
-extern void keyring_gc(struct key *keyring, time_t limit);
+extern void keyring_gc(struct key *keyring, time64_t limit);
 extern void keyring_restriction_gc(struct key *keyring,
                                   struct key_type *dead_type);
-extern void key_schedule_gc(time_t gc_at);
+extern void key_schedule_gc(time64_t gc_at);
 extern void key_schedule_gc_links(void);
 extern void key_gc_keytype(struct key_type *ktype);
 
@@ -211,7 +211,7 @@ extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
 /*
  * Determine whether a key is dead.
  */
-static inline bool key_is_dead(const struct key *key, time_t limit)
+static inline bool key_is_dead(const struct key *key, time64_t limit)
 {
        return
                key->flags & ((1 << KEY_FLAG_DEAD) |

diff --git a/security/keys/key.c b/security/keys/key.c
index 83bf4b4..32fd33d 100644 (file)
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -570,7 +570,6 @@ int key_reject_and_link(struct key *key,
                        struct key *authkey)
 {
        struct assoc_array_edit *edit;
-       struct timespec now;
        int ret, awaken, link_ret = 0;
 
        key_check(key);
@@ -593,8 +592,7 @@ int key_reject_and_link(struct key *key,
                /* mark the key as being negatively instantiated */
                atomic_inc(&key->user->nikeys);
                mark_key_instantiated(key, -error);
-               now = current_kernel_time();
-               key->expiry = now.tv_sec + timeout;
+               key->expiry = ktime_get_real_seconds() + timeout;
                key_schedule_gc(key->expiry + key_gc_delay);
 
                if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
@@ -710,16 +708,13 @@ found_kernel_type:
 
 void key_set_timeout(struct key *key, unsigned timeout)
 {
-       struct timespec now;
-       time_t expiry = 0;
+       time64_t expiry = 0;
 
        /* make the changes with the locks held to prevent races */
        down_write(&key->sem);
 
-       if (timeout > 0) {
-               now = current_kernel_time();
-               expiry = now.tv_sec + timeout;
-       }
+       if (timeout > 0)
+               expiry = ktime_get_real_seconds() + timeout;
 
        key->expiry = expiry;
        key_schedule_gc(key->expiry + key_gc_delay);
@@ -1028,8 +1023,7 @@ EXPORT_SYMBOL(key_update);
  */
 void key_revoke(struct key *key)
 {
-       struct timespec now;
-       time_t time;
+       time64_t time;
 
        key_check(key);
 
@@ -1044,8 +1038,7 @@ void key_revoke(struct key *key)
                key->type->revoke(key);
 
        /* set the death time to no more than the expiry time */
-       now = current_kernel_time();
-       time = now.tv_sec;
+       time = ktime_get_real_seconds();
        if (key->revoked_at == 0 || key->revoked_at > time) {
                key->revoked_at = time;
                key_schedule_gc(key->revoked_at + key_gc_delay);

diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 36f842e..d0bcceb 100644 (file)
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -565,7 +565,7 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
 
        /* skip invalidated, revoked and expired keys */
        if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
-               time_t expiry = READ_ONCE(key->expiry);
+               time64_t expiry = READ_ONCE(key->expiry);
 
                if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
                              (1 << KEY_FLAG_REVOKED))) {
@@ -574,7 +574,7 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
                        goto skipped;
                }
 
-               if (expiry && ctx->now.tv_sec >= expiry) {
+               if (expiry && ctx->now >= expiry) {
                        if (!(ctx->flags & KEYRING_SEARCH_SKIP_EXPIRED))
                                ctx->result = ERR_PTR(-EKEYEXPIRED);
                        kleave(" = %d [expire]", ctx->skipped_ret);
@@ -834,10 +834,10 @@ found:
        key = key_ref_to_ptr(ctx->result);
        key_check(key);
        if (!(ctx->flags & KEYRING_SEARCH_NO_UPDATE_TIME)) {
-               key->last_used_at = ctx->now.tv_sec;
-               keyring->last_used_at = ctx->now.tv_sec;
+               key->last_used_at = ctx->now;
+               keyring->last_used_at = ctx->now;
                while (sp > 0)
-                       stack[--sp].keyring->last_used_at = ctx->now.tv_sec;
+                       stack[--sp].keyring->last_used_at = ctx->now;
        }
        kleave(" = true");
        return true;
@@ -898,7 +898,7 @@ key_ref_t keyring_search_aux(key_ref_t keyring_ref,
        }
 
        rcu_read_lock();
-       ctx->now = current_kernel_time();
+       ctx->now = ktime_get_real_seconds();
        if (search_nested_keyrings(keyring, ctx))
                __key_get(key_ref_to_ptr(ctx->result));
        rcu_read_unlock();
@@ -1149,7 +1149,7 @@ struct key *find_keyring_by_name(const char *name, bool uid_keyring)
                         * (ie. it has a zero usage count) */
                        if (!refcount_inc_not_zero(&keyring->usage))
                                continue;
-                       keyring->last_used_at = current_kernel_time().tv_sec;
+                       keyring->last_used_at = ktime_get_real_seconds();
                        goto out;
                }
        }
@@ -1489,7 +1489,7 @@ static void keyring_revoke(struct key *keyring)
 static bool keyring_gc_select_iterator(void *object, void *iterator_data)
 {
        struct key *key = keyring_ptr_to_key(object);
-       time_t *limit = iterator_data;
+       time64_t *limit = iterator_data;
 
        if (key_is_dead(key, *limit))
                return false;
@@ -1500,7 +1500,7 @@ static bool keyring_gc_select_iterator(void *object, void *iterator_data)
 static int keyring_gc_check_iterator(const void *object, void *iterator_data)
 {
        const struct key *key = keyring_ptr_to_key(object);
-       time_t *limit = iterator_data;
+       time64_t *limit = iterator_data;
 
        key_check(key);
        return key_is_dead(key, *limit);
@@ -1512,7 +1512,7 @@ static int keyring_gc_check_iterator(const void *object, void *iterator_data)
  * Not called with any locks held.  The keyring's key struct will not be
  * deallocated under us as only our caller may deallocate it.
  */
-void keyring_gc(struct key *keyring, time_t limit)
+void keyring_gc(struct key *keyring, time64_t limit)
 {
        int result;
 

diff --git a/security/keys/permission.c b/security/keys/permission.c
index a72b4dd..f68dc04 100644 (file)
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -89,7 +89,7 @@ EXPORT_SYMBOL(key_task_permission);
 int key_validate(const struct key *key)
 {
        unsigned long flags = READ_ONCE(key->flags);
-       time_t expiry = READ_ONCE(key->expiry);
+       time64_t expiry = READ_ONCE(key->expiry);
 
        if (flags & (1 << KEY_FLAG_INVALIDATED))
                return -ENOKEY;
@@ -101,8 +101,7 @@ int key_validate(const struct key *key)
 
        /* check it hasn't expired */
        if (expiry) {
-               struct timespec now = current_kernel_time();
-               if (now.tv_sec >= expiry)
+               if (ktime_get_real_seconds() >= expiry)
                        return -EKEYEXPIRED;
        }
 

diff --git a/security/keys/proc.c b/security/keys/proc.c
index 6d1fcbb..fbc4af5 100644 (file)
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -178,13 +178,12 @@ static int proc_keys_show(struct seq_file *m, void *v)
 {
        struct rb_node *_p = v;
        struct key *key = rb_entry(_p, struct key, serial_node);
-       struct timespec now;
-       time_t expiry;
-       unsigned long timo;
        unsigned long flags;
        key_ref_t key_ref, skey_ref;
+       time64_t now, expiry;
        char xbuf[16];
        short state;
+       u64 timo;
        int rc;
 
        struct keyring_search_context ctx = {
@@ -215,7 +214,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
        if (rc < 0)
                return 0;
 
-       now = current_kernel_time();
+       now = ktime_get_real_seconds();
 
        rcu_read_lock();
 
@@ -223,21 +222,21 @@ static int proc_keys_show(struct seq_file *m, void *v)
        expiry = READ_ONCE(key->expiry);
        if (expiry == 0) {
                memcpy(xbuf, "perm", 5);
-       } else if (now.tv_sec >= expiry) {
+       } else if (now >= expiry) {
                memcpy(xbuf, "expd", 5);
        } else {
-               timo = expiry - now.tv_sec;
+               timo = expiry - now;
 
                if (timo < 60)
-                       sprintf(xbuf, "%lus", timo);
+                       sprintf(xbuf, "%llus", timo);
                else if (timo < 60*60)
-                       sprintf(xbuf, "%lum", timo / 60);
+                       sprintf(xbuf, "%llum", div_u64(timo, 60));
                else if (timo < 60*60*24)
-                       sprintf(xbuf, "%luh", timo / (60*60));
+                       sprintf(xbuf, "%lluh", div_u64(timo, 60 * 60));
                else if (timo < 60*60*24*7)
-                       sprintf(xbuf, "%lud", timo / (60*60*24));
+                       sprintf(xbuf, "%llud", div_u64(timo, 60 * 60 * 24));
                else
-                       sprintf(xbuf, "%luw", timo / (60*60*24*7));
+                       sprintf(xbuf, "%lluw", div_u64(timo, 60 * 60 * 24 * 7));
        }
 
        state = key_read_state(key);

diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 740affd..d5b25e5 100644 (file)
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -738,7 +738,7 @@ try_again:
        if (ret < 0)
                goto invalid_key;
 
-       key->last_used_at = current_kernel_time().tv_sec;
+       key->last_used_at = ktime_get_real_seconds();
 
 error:
        put_cred(ctx.cred);