diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 40 | ||||
| -rw-r--r-- | lib/Makefile | 2 | ||||
| -rw-r--r-- | lib/debugobjects.c | 58 | ||||
| -rw-r--r-- | lib/halfmd4.c | 67 | ||||
| -rw-r--r-- | lib/timerqueue.c | 3 |
5 files changed, 74 insertions, 96 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index eb9e9a7870fa..acedbe626d47 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -716,6 +716,19 @@ source "lib/Kconfig.kmemcheck" source "lib/Kconfig.kasan" +config DEBUG_REFCOUNT + bool "Verbose refcount checks" + help + Say Y here if you want reference counters (refcount_t and kref) to + generate WARNs on dubious usage. Without this refcount_t will still + be a saturating counter and avoid Use-After-Free by turning it into + a resource leak Denial-Of-Service. + + Use of this option will increase kernel text size but will alert the + admin of potential abuse. + + If in doubt, say "N". + endmenu # "Memory Debugging" config ARCH_HAS_KCOV @@ -980,20 +993,6 @@ config DEBUG_TIMEKEEPING If unsure, say N. -config TIMER_STATS - bool "Collect kernel timers statistics" - depends on DEBUG_KERNEL && PROC_FS - help - If you say Y here, additional code will be inserted into the - timer routines to collect statistics about kernel timers being - reprogrammed. The statistics can be read from /proc/timer_stats. - The statistics collection is started by writing 1 to /proc/timer_stats, - writing 0 stops it. This feature is useful to collect information - about timer usage patterns in kernel and userspace. This feature - is lightweight if enabled in the kernel config but not activated - (it defaults to deactivated on bootup and will only be activated - if some application like powertop activates it explicitly). - config DEBUG_PREEMPT bool "Debug preemptible kernel" depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT @@ -1180,6 +1179,18 @@ config LOCK_TORTURE_TEST Say M if you want these torture tests to build as a module. Say N if you are unsure. +config WW_MUTEX_SELFTEST + tristate "Wait/wound mutex selftests" + help + This option provides a kernel module that runs tests on the + on the struct ww_mutex locking API. + + It is recommended to enable DEBUG_WW_MUTEX_SLOWPATH in conjunction + with this test harness. + + Say M if you want these self tests to build as a module. + Say N if you are unsure. + endmenu # lock debugging config TRACE_IRQFLAGS @@ -1450,6 +1461,7 @@ config RCU_CPU_STALL_TIMEOUT config RCU_TRACE bool "Enable tracing for RCU" depends on DEBUG_KERNEL + default y if TREE_RCU select TRACE_CLOCK help This option provides tracing in RCU which presents stats diff --git a/lib/Makefile b/lib/Makefile index bc4073a8cd08..19ea76149a37 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -31,7 +31,7 @@ lib-$(CONFIG_HAS_DMA) += dma-noop.o lib-y += kobject.o klist.o obj-y += lockref.o -obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ +obj-y += bcd.o div64.o sort.o parser.o debug_locks.o random32.o \ bust_spinlocks.o kasprintf.o bitmap.o scatterlist.o \ gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \ bsearch.o find_bit.o llist.o memweight.o kfifo.o \ diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 04c1ef717fe0..8c28cbd7e104 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -52,9 +52,18 @@ static int debug_objects_fixups __read_mostly; static int debug_objects_warnings __read_mostly; static int debug_objects_enabled __read_mostly = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT; - +static int debug_objects_pool_size __read_mostly + = ODEBUG_POOL_SIZE; +static int debug_objects_pool_min_level __read_mostly + = ODEBUG_POOL_MIN_LEVEL; static struct debug_obj_descr *descr_test __read_mostly; +/* + * Track numbers of kmem_cache_alloc()/free() calls done. + */ +static int debug_objects_allocated; +static int debug_objects_freed; + static void free_obj_work(struct work_struct *work); static DECLARE_WORK(debug_obj_work, free_obj_work); @@ -88,13 +97,13 @@ static void fill_pool(void) struct debug_obj *new; unsigned long flags; - if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL)) + if (likely(obj_pool_free >= debug_objects_pool_min_level)) return; if (unlikely(!obj_cache)) return; - while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) { + while (obj_pool_free < debug_objects_pool_min_level) { new = kmem_cache_zalloc(obj_cache, gfp); if (!new) @@ -102,6 +111,7 @@ static void fill_pool(void) raw_spin_lock_irqsave(&pool_lock, flags); hlist_add_head(&new->node, &obj_pool); + debug_objects_allocated++; obj_pool_free++; raw_spin_unlock_irqrestore(&pool_lock, flags); } @@ -162,24 +172,39 @@ alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) /* * workqueue function to free objects. + * + * To reduce contention on the global pool_lock, the actual freeing of + * debug objects will be delayed if the pool_lock is busy. We also free + * the objects in a batch of 4 for each lock/unlock cycle. */ +#define ODEBUG_FREE_BATCH 4 + static void free_obj_work(struct work_struct *work) { - struct debug_obj *obj; + struct debug_obj *objs[ODEBUG_FREE_BATCH]; unsigned long flags; + int i; - raw_spin_lock_irqsave(&pool_lock, flags); - while (obj_pool_free > ODEBUG_POOL_SIZE) { - obj = hlist_entry(obj_pool.first, typeof(*obj), node); - hlist_del(&obj->node); - obj_pool_free--; + if (!raw_spin_trylock_irqsave(&pool_lock, flags)) + return; + while (obj_pool_free >= debug_objects_pool_size + ODEBUG_FREE_BATCH) { + for (i = 0; i < ODEBUG_FREE_BATCH; i++) { + objs[i] = hlist_entry(obj_pool.first, + typeof(*objs[0]), node); + hlist_del(&objs[i]->node); + } + + obj_pool_free -= ODEBUG_FREE_BATCH; + debug_objects_freed += ODEBUG_FREE_BATCH; /* * We release pool_lock across kmem_cache_free() to * avoid contention on pool_lock. */ raw_spin_unlock_irqrestore(&pool_lock, flags); - kmem_cache_free(obj_cache, obj); - raw_spin_lock_irqsave(&pool_lock, flags); + for (i = 0; i < ODEBUG_FREE_BATCH; i++) + kmem_cache_free(obj_cache, objs[i]); + if (!raw_spin_trylock_irqsave(&pool_lock, flags)) + return; } raw_spin_unlock_irqrestore(&pool_lock, flags); } @@ -198,7 +223,7 @@ static void free_object(struct debug_obj *obj) * schedule work when the pool is filled and the cache is * initialized: */ - if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache) + if (obj_pool_free > debug_objects_pool_size && obj_cache) sched = 1; hlist_add_head(&obj->node, &obj_pool); obj_pool_free++; @@ -758,6 +783,8 @@ static int debug_stats_show(struct seq_file *m, void *v) seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free); seq_printf(m, "pool_used :%d\n", obj_pool_used); seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used); + seq_printf(m, "objs_allocated:%d\n", debug_objects_allocated); + seq_printf(m, "objs_freed :%d\n", debug_objects_freed); return 0; } @@ -1116,4 +1143,11 @@ void __init debug_objects_mem_init(void) pr_warn("out of memory.\n"); } else debug_objects_selftest(); + + /* + * Increase the thresholds for allocating and freeing objects + * according to the number of possible CPUs available in the system. + */ + debug_objects_pool_size += num_possible_cpus() * 32; + debug_objects_pool_min_level += num_possible_cpus() * 4; } diff --git a/lib/halfmd4.c b/lib/halfmd4.c deleted file mode 100644 index 137e861d9690..000000000000 --- a/lib/halfmd4.c +++ /dev/null @@ -1,67 +0,0 @@ -#include <linux/compiler.h> -#include <linux/export.h> -#include <linux/cryptohash.h> -#include <linux/bitops.h> - -/* F, G and H are basic MD4 functions: selection, majority, parity */ -#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) -#define G(x, y, z) (((x) & (y)) + (((x) ^ (y)) & (z))) -#define H(x, y, z) ((x) ^ (y) ^ (z)) - -/* - * The generic round function. The application is so specific that - * we don't bother protecting all the arguments with parens, as is generally - * good macro practice, in favor of extra legibility. - * Rotation is separate from addition to prevent recomputation - */ -#define ROUND(f, a, b, c, d, x, s) \ - (a += f(b, c, d) + x, a = rol32(a, s)) -#define K1 0 -#define K2 013240474631UL -#define K3 015666365641UL - -/* - * Basic cut-down MD4 transform. Returns only 32 bits of result. - */ -__u32 half_md4_transform(__u32 buf[4], __u32 const in[8]) -{ - __u32 a = buf[0], b = buf[1], c = buf[2], d = buf[3]; - - /* Round 1 */ - ROUND(F, a, b, c, d, in[0] + K1, 3); - ROUND(F, d, a, b, c, in[1] + K1, 7); - ROUND(F, c, d, a, b, in[2] + K1, 11); - ROUND(F, b, c, d, a, in[3] + K1, 19); - ROUND(F, a, b, c, d, in[4] + K1, 3); - ROUND(F, d, a, b, c, in[5] + K1, 7); - ROUND(F, c, d, a, b, in[6] + K1, 11); - ROUND(F, b, c, d, a, in[7] + K1, 19); - - /* Round 2 */ - ROUND(G, a, b, c, d, in[1] + K2, 3); - ROUND(G, d, a, b, c, in[3] + K2, 5); - ROUND(G, c, d, a, b, in[5] + K2, 9); - ROUND(G, b, c, d, a, in[7] + K2, 13); - ROUND(G, a, b, c, d, in[0] + K2, 3); - ROUND(G, d, a, b, c, in[2] + K2, 5); - ROUND(G, c, d, a, b, in[4] + K2, 9); - ROUND(G, b, c, d, a, in[6] + K2, 13); - - /* Round 3 */ - ROUND(H, a, b, c, d, in[3] + K3, 3); - ROUND(H, d, a, b, c, in[7] + K3, 9); - ROUND(H, c, d, a, b, in[2] + K3, 11); - ROUND(H, b, c, d, a, in[6] + K3, 15); - ROUND(H, a, b, c, d, in[1] + K3, 3); - ROUND(H, d, a, b, c, in[5] + K3, 9); - ROUND(H, c, d, a, b, in[0] + K3, 11); - ROUND(H, b, c, d, a, in[4] + K3, 15); - - buf[0] += a; - buf[1] += b; - buf[2] += c; - buf[3] += d; - - return buf[1]; /* "most hashed" word */ -} -EXPORT_SYMBOL(half_md4_transform); diff --git a/lib/timerqueue.c b/lib/timerqueue.c index adc6ee0a5126..4a720ed4fdaf 100644 --- a/lib/timerqueue.c +++ b/lib/timerqueue.c @@ -80,8 +80,7 @@ bool timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node) if (head->next == node) { struct rb_node *rbn = rb_next(&node->node); - head->next = rbn ? - rb_entry(rbn, struct timerqueue_node, node) : NULL; + head->next = rb_entry_safe(rbn, struct timerqueue_node, node); } rb_erase(&node->node, &head->head); RB_CLEAR_NODE(&node->node); |