diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/dynamic_debug.c | 20 | ||||
| -rw-r--r-- | lib/test_kasan.c | 29 |
2 files changed, 35 insertions, 14 deletions
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 921d0a654243..641767b0dce2 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -586,13 +586,11 @@ static int remaining(int wrote) return 0; } -static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) +static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) { int pos_after_tid; int pos = 0; - *buf = '\0'; - if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { if (in_interrupt()) pos += snprintf(buf + pos, remaining(pos), "<intr> "); @@ -618,11 +616,18 @@ static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) return buf; } +static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf) +{ + if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY)) + return __dynamic_emit_prefix(desc, buf); + return buf; +} + void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) { va_list args; struct va_format vaf; - char buf[PREFIX_SIZE]; + char buf[PREFIX_SIZE] = ""; BUG_ON(!descriptor); BUG_ON(!fmt); @@ -655,7 +660,7 @@ void __dynamic_dev_dbg(struct _ddebug *descriptor, if (!dev) { printk(KERN_DEBUG "(NULL device *): %pV", &vaf); } else { - char buf[PREFIX_SIZE]; + char buf[PREFIX_SIZE] = ""; dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV", dynamic_emit_prefix(descriptor, buf), @@ -684,7 +689,7 @@ void __dynamic_netdev_dbg(struct _ddebug *descriptor, vaf.va = &args; if (dev && dev->dev.parent) { - char buf[PREFIX_SIZE]; + char buf[PREFIX_SIZE] = ""; dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent, "%s%s %s %s%s: %pV", @@ -720,7 +725,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, vaf.va = &args; if (ibdev && ibdev->dev.parent) { - char buf[PREFIX_SIZE]; + char buf[PREFIX_SIZE] = ""; dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent, "%s%s %s %s: %pV", @@ -915,7 +920,6 @@ static const struct seq_operations ddebug_proc_seqops = { static int ddebug_proc_open(struct inode *inode, struct file *file) { - vpr_info("called\n"); return seq_open_private(file, &ddebug_proc_seqops, sizeof(struct ddebug_iter)); } diff --git a/lib/test_kasan.c b/lib/test_kasan.c index dc05cfc2d12f..cacbbbdef768 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -654,8 +654,20 @@ static char global_array[10]; static void kasan_global_oob(struct kunit *test) { - volatile int i = 3; - char *p = &global_array[ARRAY_SIZE(global_array) + i]; + /* + * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS + * from failing here and panicing the kernel, access the array via a + * volatile pointer, which will prevent the compiler from being able to + * determine the array bounds. + * + * This access uses a volatile pointer to char (char *volatile) rather + * than the more conventional pointer to volatile char (volatile char *) + * because we want to prevent the compiler from making inferences about + * the pointer itself (i.e. its array bounds), not the data that it + * refers to. + */ + char *volatile array = global_array; + char *p = &array[ARRAY_SIZE(global_array) + 3]; /* Only generic mode instruments globals. */ KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); @@ -703,8 +715,9 @@ static void ksize_uaf(struct kunit *test) static void kasan_stack_oob(struct kunit *test) { char stack_array[10]; - volatile int i = OOB_TAG_OFF; - char *p = &stack_array[ARRAY_SIZE(stack_array) + i]; + /* See comment in kasan_global_oob. */ + char *volatile array = stack_array; + char *p = &array[ARRAY_SIZE(stack_array) + OOB_TAG_OFF]; KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); @@ -715,7 +728,9 @@ static void kasan_alloca_oob_left(struct kunit *test) { volatile int i = 10; char alloca_array[i]; - char *p = alloca_array - 1; + /* See comment in kasan_global_oob. */ + char *volatile array = alloca_array; + char *p = array - 1; /* Only generic mode instruments dynamic allocas. */ KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); @@ -728,7 +743,9 @@ static void kasan_alloca_oob_right(struct kunit *test) { volatile int i = 10; char alloca_array[i]; - char *p = alloca_array + i; + /* See comment in kasan_global_oob. */ + char *volatile array = alloca_array; + char *p = array + i; /* Only generic mode instruments dynamic allocas. */ KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); |