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-rw-r--r--lib/Kconfig.debug18
-rw-r--r--lib/debugobjects.c8
-rw-r--r--lib/iov_iter.c4
-rw-r--r--lib/list_debug.c99
-rw-r--r--lib/locking-selftest.c66
-rw-r--r--lib/mpi/mpi-pow.c7
-rw-r--r--lib/nlattr.c2
-rw-r--r--lib/test_kasan.c29
8 files changed, 125 insertions, 108 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b01e547d4d04..9bb7d825ba14 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1085,6 +1085,9 @@ config PROVE_LOCKING
For more details, see Documentation/locking/lockdep-design.txt.
+config PROVE_LOCKING_SMALL
+ bool
+
config LOCKDEP
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
@@ -1215,7 +1218,7 @@ config DEBUG_BUGVERBOSE
config DEBUG_LIST
bool "Debug linked list manipulation"
- depends on DEBUG_KERNEL
+ depends on DEBUG_KERNEL || BUG_ON_DATA_CORRUPTION
help
Enable this to turn on extended checks in the linked-list
walking routines.
@@ -1431,7 +1434,8 @@ config RCU_TRACE
select TRACE_CLOCK
help
This option provides tracing in RCU which presents stats
- in debugfs for debugging RCU implementation.
+ in debugfs for debugging RCU implementation. It also enables
+ additional tracepoints for ftrace-style event tracing.
Say Y here if you want to enable RCU tracing
Say N if you are unsure.
@@ -1961,6 +1965,16 @@ config TEST_STATIC_KEYS
If unsure, say N.
+config BUG_ON_DATA_CORRUPTION
+ bool "Trigger a BUG when data corruption is detected"
+ select DEBUG_LIST
+ help
+ Select this option if the kernel should BUG when it encounters
+ data corruption in kernel memory structures when they get checked
+ for validity.
+
+ If unsure, say N.
+
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index a8e12601eb37..056052dc8e91 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -362,6 +362,7 @@ void debug_object_init(void *addr, struct debug_obj_descr *descr)
__debug_object_init(addr, descr, 0);
}
+EXPORT_SYMBOL_GPL(debug_object_init);
/**
* debug_object_init_on_stack - debug checks when an object on stack is
@@ -376,6 +377,7 @@ void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
__debug_object_init(addr, descr, 1);
}
+EXPORT_SYMBOL_GPL(debug_object_init_on_stack);
/**
* debug_object_activate - debug checks when an object is activated
@@ -449,6 +451,7 @@ int debug_object_activate(void *addr, struct debug_obj_descr *descr)
}
return 0;
}
+EXPORT_SYMBOL_GPL(debug_object_activate);
/**
* debug_object_deactivate - debug checks when an object is deactivated
@@ -496,6 +499,7 @@ void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+EXPORT_SYMBOL_GPL(debug_object_deactivate);
/**
* debug_object_destroy - debug checks when an object is destroyed
@@ -542,6 +546,7 @@ void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
out_unlock:
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+EXPORT_SYMBOL_GPL(debug_object_destroy);
/**
* debug_object_free - debug checks when an object is freed
@@ -582,6 +587,7 @@ void debug_object_free(void *addr, struct debug_obj_descr *descr)
out_unlock:
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+EXPORT_SYMBOL_GPL(debug_object_free);
/**
* debug_object_assert_init - debug checks when object should be init-ed
@@ -626,6 +632,7 @@ void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+EXPORT_SYMBOL_GPL(debug_object_assert_init);
/**
* debug_object_active_state - debug checks object usage state machine
@@ -673,6 +680,7 @@ debug_object_active_state(void *addr, struct debug_obj_descr *descr,
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+EXPORT_SYMBOL_GPL(debug_object_active_state);
#ifdef CONFIG_DEBUG_OBJECTS_FREE
static void __debug_check_no_obj_freed(const void *address, unsigned long size)
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index f0c7f1481bae..f2bd21b93dfc 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -683,10 +683,11 @@ static void pipe_advance(struct iov_iter *i, size_t size)
struct pipe_inode_info *pipe = i->pipe;
struct pipe_buffer *buf;
int idx = i->idx;
- size_t off = i->iov_offset;
+ size_t off = i->iov_offset, orig_sz;
if (unlikely(i->count < size))
size = i->count;
+ orig_sz = size;
if (size) {
if (off) /* make it relative to the beginning of buffer */
@@ -713,6 +714,7 @@ static void pipe_advance(struct iov_iter *i, size_t size)
pipe->nrbufs--;
}
}
+ i->count -= orig_sz;
}
void iov_iter_advance(struct iov_iter *i, size_t size)
diff --git a/lib/list_debug.c b/lib/list_debug.c
index 3859bf63561c..7f7bfa55eb6d 100644
--- a/lib/list_debug.c
+++ b/lib/list_debug.c
@@ -2,8 +2,7 @@
* Copyright 2006, Red Hat, Inc., Dave Jones
* Released under the General Public License (GPL).
*
- * This file contains the linked list implementations for
- * DEBUG_LIST.
+ * This file contains the linked list validation for DEBUG_LIST.
*/
#include <linux/export.h>
@@ -13,88 +12,48 @@
#include <linux/rculist.h>
/*
- * Insert a new entry between two known consecutive entries.
- *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
+ * Check that the data structures for the list manipulations are reasonably
+ * valid. Failures here indicate memory corruption (and possibly an exploit
+ * attempt).
*/
-void __list_add(struct list_head *new,
- struct list_head *prev,
- struct list_head *next)
+bool __list_add_valid(struct list_head *new, struct list_head *prev,
+ struct list_head *next)
{
- WARN(next->prev != prev,
- "list_add corruption. next->prev should be "
- "prev (%p), but was %p. (next=%p).\n",
+ CHECK_DATA_CORRUPTION(next->prev != prev,
+ "list_add corruption. next->prev should be prev (%p), but was %p. (next=%p).\n",
prev, next->prev, next);
- WARN(prev->next != next,
- "list_add corruption. prev->next should be "
- "next (%p), but was %p. (prev=%p).\n",
+ CHECK_DATA_CORRUPTION(prev->next != next,
+ "list_add corruption. prev->next should be next (%p), but was %p. (prev=%p).\n",
next, prev->next, prev);
- WARN(new == prev || new == next,
- "list_add double add: new=%p, prev=%p, next=%p.\n",
- new, prev, next);
- next->prev = new;
- new->next = next;
- new->prev = prev;
- WRITE_ONCE(prev->next, new);
+ CHECK_DATA_CORRUPTION(new == prev || new == next,
+ "list_add double add: new=%p, prev=%p, next=%p.\n",
+ new, prev, next);
+
+ return true;
}
-EXPORT_SYMBOL(__list_add);
+EXPORT_SYMBOL(__list_add_valid);
-void __list_del_entry(struct list_head *entry)
+bool __list_del_entry_valid(struct list_head *entry)
{
struct list_head *prev, *next;
prev = entry->prev;
next = entry->next;
- if (WARN(next == LIST_POISON1,
+ CHECK_DATA_CORRUPTION(next == LIST_POISON1,
"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
- entry, LIST_POISON1) ||
- WARN(prev == LIST_POISON2,
+ entry, LIST_POISON1);
+ CHECK_DATA_CORRUPTION(prev == LIST_POISON2,
"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
- entry, LIST_POISON2) ||
- WARN(prev->next != entry,
- "list_del corruption. prev->next should be %p, "
- "but was %p\n", entry, prev->next) ||
- WARN(next->prev != entry,
- "list_del corruption. next->prev should be %p, "
- "but was %p\n", entry, next->prev))
- return;
-
- __list_del(prev, next);
-}
-EXPORT_SYMBOL(__list_del_entry);
+ entry, LIST_POISON2);
+ CHECK_DATA_CORRUPTION(prev->next != entry,
+ "list_del corruption. prev->next should be %p, but was %p\n",
+ entry, prev->next);
+ CHECK_DATA_CORRUPTION(next->prev != entry,
+ "list_del corruption. next->prev should be %p, but was %p\n",
+ entry, next->prev);
+ return true;
-/**
- * list_del - deletes entry from list.
- * @entry: the element to delete from the list.
- * Note: list_empty on entry does not return true after this, the entry is
- * in an undefined state.
- */
-void list_del(struct list_head *entry)
-{
- __list_del_entry(entry);
- entry->next = LIST_POISON1;
- entry->prev = LIST_POISON2;
-}
-EXPORT_SYMBOL(list_del);
-
-/*
- * RCU variants.
- */
-void __list_add_rcu(struct list_head *new,
- struct list_head *prev, struct list_head *next)
-{
- WARN(next->prev != prev,
- "list_add_rcu corruption. next->prev should be prev (%p), but was %p. (next=%p).\n",
- prev, next->prev, next);
- WARN(prev->next != next,
- "list_add_rcu corruption. prev->next should be next (%p), but was %p. (prev=%p).\n",
- next, prev->next, prev);
- new->next = next;
- new->prev = prev;
- rcu_assign_pointer(list_next_rcu(prev), new);
- next->prev = new;
}
-EXPORT_SYMBOL(__list_add_rcu);
+EXPORT_SYMBOL(__list_del_entry_valid);
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 872a15a2a637..f3a217ea0388 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -980,23 +980,23 @@ static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
#ifndef CONFIG_PROVE_LOCKING
if (expected == FAILURE && debug_locks) {
expected_testcase_failures++;
- printk("failed|");
+ pr_cont("failed|");
}
else
#endif
if (debug_locks != expected) {
unexpected_testcase_failures++;
- printk("FAILED|");
+ pr_cont("FAILED|");
dump_stack();
} else {
testcase_successes++;
- printk(" ok |");
+ pr_cont(" ok |");
}
testcase_total++;
if (debug_locks_verbose)
- printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
+ pr_cont(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
lockclass_mask, debug_locks, expected);
/*
* Some tests (e.g. double-unlock) might corrupt the preemption
@@ -1021,26 +1021,26 @@ static inline void print_testname(const char *testname)
#define DO_TESTCASE_1(desc, name, nr) \
print_testname(desc"/"#nr); \
dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_1B(desc, name, nr) \
print_testname(desc"/"#nr); \
dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_3(desc, name, nr) \
print_testname(desc"/"#nr); \
dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \
dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_3RW(desc, name, nr) \
print_testname(desc"/"#nr); \
dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\
dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_6(desc, name) \
print_testname(desc); \
@@ -1050,7 +1050,7 @@ static inline void print_testname(const char *testname)
dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_6_SUCCESS(desc, name) \
print_testname(desc); \
@@ -1060,7 +1060,7 @@ static inline void print_testname(const char *testname)
dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \
dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \
dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \
- printk("\n");
+ pr_cont("\n");
/*
* 'read' variant: rlocks must not trigger.
@@ -1073,7 +1073,7 @@ static inline void print_testname(const char *testname)
dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
- printk("\n");
+ pr_cont("\n");
#define DO_TESTCASE_2I(desc, name, nr) \
DO_TESTCASE_1("hard-"desc, name##_hard, nr); \
@@ -1726,25 +1726,25 @@ static void ww_tests(void)
dotest(ww_test_fail_acquire, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_normal, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_unneeded_slow, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("ww contexts mixing");
dotest(ww_test_two_contexts, FAILURE, LOCKTYPE_WW);
dotest(ww_test_diff_class, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("finishing ww context");
dotest(ww_test_context_done_twice, FAILURE, LOCKTYPE_WW);
dotest(ww_test_context_unlock_twice, FAILURE, LOCKTYPE_WW);
dotest(ww_test_context_fini_early, FAILURE, LOCKTYPE_WW);
dotest(ww_test_context_lock_after_done, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("locking mismatches");
dotest(ww_test_object_unlock_twice, FAILURE, LOCKTYPE_WW);
dotest(ww_test_object_lock_unbalanced, FAILURE, LOCKTYPE_WW);
dotest(ww_test_object_lock_stale_context, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("EDEADLK handling");
dotest(ww_test_edeadlk_normal, SUCCESS, LOCKTYPE_WW);
@@ -1757,11 +1757,11 @@ static void ww_tests(void)
dotest(ww_test_edeadlk_acquire_more_edeadlk_slow, FAILURE, LOCKTYPE_WW);
dotest(ww_test_edeadlk_acquire_wrong, FAILURE, LOCKTYPE_WW);
dotest(ww_test_edeadlk_acquire_wrong_slow, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("spinlock nest unlocked");
dotest(ww_test_spin_nest_unlocked, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
printk(" -----------------------------------------------------\n");
printk(" |block | try |context|\n");
@@ -1771,25 +1771,25 @@ static void ww_tests(void)
dotest(ww_test_context_block, FAILURE, LOCKTYPE_WW);
dotest(ww_test_context_try, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_context_context, SUCCESS, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("try");
dotest(ww_test_try_block, FAILURE, LOCKTYPE_WW);
dotest(ww_test_try_try, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_try_context, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("block");
dotest(ww_test_block_block, FAILURE, LOCKTYPE_WW);
dotest(ww_test_block_try, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_block_context, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
print_testname("spinlock");
dotest(ww_test_spin_block, FAILURE, LOCKTYPE_WW);
dotest(ww_test_spin_try, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_spin_context, FAILURE, LOCKTYPE_WW);
- printk("\n");
+ pr_cont("\n");
}
void locking_selftest(void)
@@ -1829,32 +1829,32 @@ void locking_selftest(void)
printk(" --------------------------------------------------------------------------\n");
print_testname("recursive read-lock");
- printk(" |");
+ pr_cont(" |");
dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK);
- printk(" |");
+ pr_cont(" |");
dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM);
- printk("\n");
+ pr_cont("\n");
print_testname("recursive read-lock #2");
- printk(" |");
+ pr_cont(" |");
dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK);
- printk(" |");
+ pr_cont(" |");
dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM);
- printk("\n");
+ pr_cont("\n");
print_testname("mixed read-write-lock");
- printk(" |");
+ pr_cont(" |");
dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK);
- printk(" |");
+ pr_cont(" |");
dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM);
- printk("\n");
+ pr_cont("\n");
print_testname("mixed write-read-lock");
- printk(" |");
+ pr_cont(" |");
dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK);
- printk(" |");
+ pr_cont(" |");
dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM);
- printk("\n");
+ pr_cont("\n");
printk(" --------------------------------------------------------------------------\n");
diff --git a/lib/mpi/mpi-pow.c b/lib/mpi/mpi-pow.c
index 5464c8744ea9..e24388a863a7 100644
--- a/lib/mpi/mpi-pow.c
+++ b/lib/mpi/mpi-pow.c
@@ -64,8 +64,13 @@ int mpi_powm(MPI res, MPI base, MPI exp, MPI mod)
if (!esize) {
/* Exponent is zero, result is 1 mod MOD, i.e., 1 or 0
* depending on if MOD equals 1. */
- rp[0] = 1;
res->nlimbs = (msize == 1 && mod->d[0] == 1) ? 0 : 1;
+ if (res->nlimbs) {
+ if (mpi_resize(res, 1) < 0)
+ goto enomem;
+ rp = res->d;
+ rp[0] = 1;
+ }
res->sign = 0;
goto leave;
}
diff --git a/lib/nlattr.c b/lib/nlattr.c
index fce1e9afc6d9..b42b8577fc23 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -14,7 +14,7 @@
#include <linux/types.h>
#include <net/netlink.h>
-static const u16 nla_attr_minlen[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),
diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 5e51872b3fc1..fbdf87920093 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -20,6 +20,11 @@
#include <linux/uaccess.h>
#include <linux/module.h>
+/*
+ * Note: test functions are marked noinline so that their names appear in
+ * reports.
+ */
+
static noinline void __init kmalloc_oob_right(void)
{
char *ptr;
@@ -411,6 +416,29 @@ static noinline void __init copy_user_test(void)
kfree(kmem);
}
+static noinline void __init use_after_scope_test(void)
+{
+ volatile char *volatile p;
+
+ pr_info("use-after-scope on int\n");
+ {
+ int local = 0;
+
+ p = (char *)&local;
+ }
+ p[0] = 1;
+ p[3] = 1;
+
+ pr_info("use-after-scope on array\n");
+ {
+ char local[1024] = {0};
+
+ p = local;
+ }
+ p[0] = 1;
+ p[1023] = 1;
+}
+
static int __init kmalloc_tests_init(void)
{
kmalloc_oob_right();
@@ -436,6 +464,7 @@ static int __init kmalloc_tests_init(void)
kasan_global_oob();
ksize_unpoisons_memory();
copy_user_test();
+ use_after_scope_test();
return -EAGAIN;
}