From 074d58989569b39f04294c90ef36dd82b8c2cc1a Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Wed, 15 Nov 2017 16:38:45 +0000 Subject: [PATCH] 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 Reviewed-by: Arnd Bergmann Signed-off-by: David Howells Reviewed-by: James Morris --- include/linux/key.h | 7 ++++--- security/keys/gc.c | 20 ++++++++++---------- security/keys/internal.h | 8 ++++---- security/keys/key.c | 19 ++++++------------- security/keys/keyring.c | 20 ++++++++++---------- security/keys/permission.c | 5 ++--- security/keys/proc.c | 21 ++++++++++----------- security/keys/process_keys.c | 2 +- 8 files changed, 47 insertions(+), 55 deletions(-) diff --git a/include/linux/key.h b/include/linux/key.h index 8a15cabe928d..e58ee10f6e58 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -24,6 +24,7 @@ #include #include #include +#include #ifdef __KERNEL__ #include @@ -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this key */ union { - time_t expiry; /* time at which key expires (or 0) */ - time_t revoked_at; /* time at which key was revoked */ + time64_t expiry; /* time at which key expires (or 0) */ + time64_t revoked_at; /* time at which key was revoked */ }; - time_t last_used_at; /* last time used for LRU keyring discard */ + time64_t last_used_at; /* last time used for LRU keyring discard */ kuid_t uid;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 afb3a9175d76..6713fee893fb 100644 --- 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 503adbae7b0d..9f8208dc0e55 100644 --- 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 83bf4b4afd49..32fd33d45959 100644 --- 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 36f842ec87f0..d0bccebbd3b5 100644 --- 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 a72b4dd70c8a..f68dc04d614e 100644 --- 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 6d1fcbba1e09..fbc4af5c6c9f 100644 --- 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 740affd65ee9..d5b25e535d3a 100644 --- 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);