Linux Audio

Check our new training course

Loading...
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * UBSAN error reporting functions
  4 *
  5 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
  6 * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
  7 */
  8
  9#include <linux/bitops.h>
 10#include <linux/bug.h>
 11#include <linux/ctype.h>
 12#include <linux/init.h>
 13#include <linux/kernel.h>
 14#include <linux/types.h>
 15#include <linux/sched.h>
 16#include <linux/uaccess.h>
 17
 18#include "ubsan.h"
 19
 20static const char * const type_check_kinds[] = {
 21	"load of",
 22	"store to",
 23	"reference binding to",
 24	"member access within",
 25	"member call on",
 26	"constructor call on",
 27	"downcast of",
 28	"downcast of"
 29};
 30
 31#define REPORTED_BIT 31
 32
 33#if (BITS_PER_LONG == 64) && defined(__BIG_ENDIAN)
 34#define COLUMN_MASK (~(1U << REPORTED_BIT))
 35#define LINE_MASK   (~0U)
 36#else
 37#define COLUMN_MASK   (~0U)
 38#define LINE_MASK (~(1U << REPORTED_BIT))
 39#endif
 40
 41#define VALUE_LENGTH 40
 42
 43static bool was_reported(struct source_location *location)
 44{
 45	return test_and_set_bit(REPORTED_BIT, &location->reported);
 46}
 47
 48static bool suppress_report(struct source_location *loc)
 49{
 50	return current->in_ubsan || was_reported(loc);
 51}
 52
 53static bool type_is_int(struct type_descriptor *type)
 54{
 55	return type->type_kind == type_kind_int;
 56}
 57
 58static bool type_is_signed(struct type_descriptor *type)
 59{
 60	WARN_ON(!type_is_int(type));
 61	return  type->type_info & 1;
 62}
 63
 64static unsigned type_bit_width(struct type_descriptor *type)
 65{
 66	return 1 << (type->type_info >> 1);
 67}
 68
 69static bool is_inline_int(struct type_descriptor *type)
 70{
 71	unsigned inline_bits = sizeof(unsigned long)*8;
 72	unsigned bits = type_bit_width(type);
 73
 74	WARN_ON(!type_is_int(type));
 75
 76	return bits <= inline_bits;
 77}
 78
 79static s_max get_signed_val(struct type_descriptor *type, void *val)
 80{
 81	if (is_inline_int(type)) {
 82		unsigned extra_bits = sizeof(s_max)*8 - type_bit_width(type);
 83		unsigned long ulong_val = (unsigned long)val;
 84
 85		return ((s_max)ulong_val) << extra_bits >> extra_bits;
 86	}
 87
 88	if (type_bit_width(type) == 64)
 89		return *(s64 *)val;
 90
 91	return *(s_max *)val;
 92}
 93
 94static bool val_is_negative(struct type_descriptor *type, void *val)
 95{
 96	return type_is_signed(type) && get_signed_val(type, val) < 0;
 97}
 98
 99static u_max get_unsigned_val(struct type_descriptor *type, void *val)
100{
101	if (is_inline_int(type))
102		return (unsigned long)val;
103
104	if (type_bit_width(type) == 64)
105		return *(u64 *)val;
106
107	return *(u_max *)val;
108}
109
110static void val_to_string(char *str, size_t size, struct type_descriptor *type,
111			void *value)
112{
113	if (type_is_int(type)) {
114		if (type_bit_width(type) == 128) {
115#if defined(CONFIG_ARCH_SUPPORTS_INT128)
116			u_max val = get_unsigned_val(type, value);
117
118			scnprintf(str, size, "0x%08x%08x%08x%08x",
119				(u32)(val >> 96),
120				(u32)(val >> 64),
121				(u32)(val >> 32),
122				(u32)(val));
123#else
124			WARN_ON(1);
125#endif
126		} else if (type_is_signed(type)) {
127			scnprintf(str, size, "%lld",
128				(s64)get_signed_val(type, value));
129		} else {
130			scnprintf(str, size, "%llu",
131				(u64)get_unsigned_val(type, value));
132		}
133	}
134}
135
136static void ubsan_prologue(struct source_location *loc, const char *reason)
137{
138	current->in_ubsan++;
139
140	pr_err("========================================"
141		"========================================\n");
142	pr_err("UBSAN: %s in %s:%d:%d\n", reason, loc->file_name,
143		loc->line & LINE_MASK, loc->column & COLUMN_MASK);
144}
145
146static void ubsan_epilogue(void)
147{
148	dump_stack();
149	pr_err("========================================"
150		"========================================\n");
151
152	current->in_ubsan--;
153
154	if (panic_on_warn) {
155		/*
156		 * This thread may hit another WARN() in the panic path.
157		 * Resetting this prevents additional WARN() from panicking the
158		 * system on this thread.  Other threads are blocked by the
159		 * panic_mutex in panic().
160		 */
161		panic_on_warn = 0;
162		panic("panic_on_warn set ...\n");
163	}
164}
165
166void __ubsan_handle_divrem_overflow(void *_data, void *lhs, void *rhs)
167{
168	struct overflow_data *data = _data;
169	char rhs_val_str[VALUE_LENGTH];
170
171	if (suppress_report(&data->location))
172		return;
173
174	ubsan_prologue(&data->location, "division-overflow");
175
176	val_to_string(rhs_val_str, sizeof(rhs_val_str), data->type, rhs);
177
178	if (type_is_signed(data->type) && get_signed_val(data->type, rhs) == -1)
179		pr_err("division of %s by -1 cannot be represented in type %s\n",
180			rhs_val_str, data->type->type_name);
181	else
182		pr_err("division by zero\n");
183
184	ubsan_epilogue();
185}
186EXPORT_SYMBOL(__ubsan_handle_divrem_overflow);
187
188static void handle_null_ptr_deref(struct type_mismatch_data_common *data)
189{
190	if (suppress_report(data->location))
191		return;
192
193	ubsan_prologue(data->location, "null-ptr-deref");
194
195	pr_err("%s null pointer of type %s\n",
196		type_check_kinds[data->type_check_kind],
197		data->type->type_name);
198
199	ubsan_epilogue();
200}
201
202static void handle_misaligned_access(struct type_mismatch_data_common *data,
203				unsigned long ptr)
204{
205	if (suppress_report(data->location))
206		return;
207
208	ubsan_prologue(data->location, "misaligned-access");
209
210	pr_err("%s misaligned address %p for type %s\n",
211		type_check_kinds[data->type_check_kind],
212		(void *)ptr, data->type->type_name);
213	pr_err("which requires %ld byte alignment\n", data->alignment);
214
215	ubsan_epilogue();
216}
217
218static void handle_object_size_mismatch(struct type_mismatch_data_common *data,
219					unsigned long ptr)
220{
221	if (suppress_report(data->location))
222		return;
223
224	ubsan_prologue(data->location, "object-size-mismatch");
225	pr_err("%s address %p with insufficient space\n",
226		type_check_kinds[data->type_check_kind],
227		(void *) ptr);
228	pr_err("for an object of type %s\n", data->type->type_name);
229	ubsan_epilogue();
230}
231
232static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data,
233				unsigned long ptr)
234{
235	unsigned long flags = user_access_save();
236
237	if (!ptr)
238		handle_null_ptr_deref(data);
239	else if (data->alignment && !IS_ALIGNED(ptr, data->alignment))
240		handle_misaligned_access(data, ptr);
241	else
242		handle_object_size_mismatch(data, ptr);
243
244	user_access_restore(flags);
245}
246
247void __ubsan_handle_type_mismatch(struct type_mismatch_data *data,
248				void *ptr)
249{
250	struct type_mismatch_data_common common_data = {
251		.location = &data->location,
252		.type = data->type,
253		.alignment = data->alignment,
254		.type_check_kind = data->type_check_kind
255	};
256
257	ubsan_type_mismatch_common(&common_data, (unsigned long)ptr);
258}
259EXPORT_SYMBOL(__ubsan_handle_type_mismatch);
260
261void __ubsan_handle_type_mismatch_v1(void *_data, void *ptr)
262{
263	struct type_mismatch_data_v1 *data = _data;
264	struct type_mismatch_data_common common_data = {
265		.location = &data->location,
266		.type = data->type,
267		.alignment = 1UL << data->log_alignment,
268		.type_check_kind = data->type_check_kind
269	};
270
271	ubsan_type_mismatch_common(&common_data, (unsigned long)ptr);
272}
273EXPORT_SYMBOL(__ubsan_handle_type_mismatch_v1);
274
275void __ubsan_handle_out_of_bounds(void *_data, void *index)
276{
277	struct out_of_bounds_data *data = _data;
278	char index_str[VALUE_LENGTH];
279
280	if (suppress_report(&data->location))
281		return;
282
283	ubsan_prologue(&data->location, "array-index-out-of-bounds");
284
285	val_to_string(index_str, sizeof(index_str), data->index_type, index);
286	pr_err("index %s is out of range for type %s\n", index_str,
287		data->array_type->type_name);
288	ubsan_epilogue();
289}
290EXPORT_SYMBOL(__ubsan_handle_out_of_bounds);
291
292void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs)
293{
294	struct shift_out_of_bounds_data *data = _data;
295	struct type_descriptor *rhs_type = data->rhs_type;
296	struct type_descriptor *lhs_type = data->lhs_type;
297	char rhs_str[VALUE_LENGTH];
298	char lhs_str[VALUE_LENGTH];
299	unsigned long ua_flags = user_access_save();
300
301	if (suppress_report(&data->location))
302		goto out;
303
304	ubsan_prologue(&data->location, "shift-out-of-bounds");
305
306	val_to_string(rhs_str, sizeof(rhs_str), rhs_type, rhs);
307	val_to_string(lhs_str, sizeof(lhs_str), lhs_type, lhs);
308
309	if (val_is_negative(rhs_type, rhs))
310		pr_err("shift exponent %s is negative\n", rhs_str);
311
312	else if (get_unsigned_val(rhs_type, rhs) >=
313		type_bit_width(lhs_type))
314		pr_err("shift exponent %s is too large for %u-bit type %s\n",
315			rhs_str,
316			type_bit_width(lhs_type),
317			lhs_type->type_name);
318	else if (val_is_negative(lhs_type, lhs))
319		pr_err("left shift of negative value %s\n",
320			lhs_str);
321	else
322		pr_err("left shift of %s by %s places cannot be"
323			" represented in type %s\n",
324			lhs_str, rhs_str,
325			lhs_type->type_name);
326
327	ubsan_epilogue();
328out:
329	user_access_restore(ua_flags);
330}
331EXPORT_SYMBOL(__ubsan_handle_shift_out_of_bounds);
332
333
334void __ubsan_handle_builtin_unreachable(void *_data)
335{
336	struct unreachable_data *data = _data;
337	ubsan_prologue(&data->location, "unreachable");
338	pr_err("calling __builtin_unreachable()\n");
339	ubsan_epilogue();
340	panic("can't return from __builtin_unreachable()");
341}
342EXPORT_SYMBOL(__ubsan_handle_builtin_unreachable);
343
344void __ubsan_handle_load_invalid_value(void *_data, void *val)
345{
346	struct invalid_value_data *data = _data;
347	char val_str[VALUE_LENGTH];
348
349	if (suppress_report(&data->location))
350		return;
351
352	ubsan_prologue(&data->location, "invalid-load");
353
354	val_to_string(val_str, sizeof(val_str), data->type, val);
355
356	pr_err("load of value %s is not a valid value for type %s\n",
357		val_str, data->type->type_name);
358
359	ubsan_epilogue();
360}
361EXPORT_SYMBOL(__ubsan_handle_load_invalid_value);
362
363void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
364					 unsigned long align,
365					 unsigned long offset);
366void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
367					 unsigned long align,
368					 unsigned long offset)
369{
370	struct alignment_assumption_data *data = _data;
371	unsigned long real_ptr;
372
373	if (suppress_report(&data->location))
374		return;
375
376	ubsan_prologue(&data->location, "alignment-assumption");
377
378	if (offset)
379		pr_err("assumption of %lu byte alignment (with offset of %lu byte) for pointer of type %s failed",
380		       align, offset, data->type->type_name);
381	else
382		pr_err("assumption of %lu byte alignment for pointer of type %s failed",
383		       align, data->type->type_name);
384
385	real_ptr = ptr - offset;
386	pr_err("%saddress is %lu aligned, misalignment offset is %lu bytes",
387	       offset ? "offset " : "", BIT(real_ptr ? __ffs(real_ptr) : 0),
388	       real_ptr & (align - 1));
389
390	ubsan_epilogue();
391}
392EXPORT_SYMBOL(__ubsan_handle_alignment_assumption);
  1/*
  2 * UBSAN error reporting functions
  3 *
  4 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
  5 * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 *
 11 */
 12
 13#include <linux/bitops.h>
 14#include <linux/bug.h>
 15#include <linux/ctype.h>
 16#include <linux/init.h>
 17#include <linux/kernel.h>
 18#include <linux/types.h>
 19#include <linux/sched.h>
 20
 21#include "ubsan.h"
 22
 23const char *type_check_kinds[] = {
 24	"load of",
 25	"store to",
 26	"reference binding to",
 27	"member access within",
 28	"member call on",
 29	"constructor call on",
 30	"downcast of",
 31	"downcast of"
 32};
 33
 34#define REPORTED_BIT 31
 35
 36#if (BITS_PER_LONG == 64) && defined(__BIG_ENDIAN)
 37#define COLUMN_MASK (~(1U << REPORTED_BIT))
 38#define LINE_MASK   (~0U)
 39#else
 40#define COLUMN_MASK   (~0U)
 41#define LINE_MASK (~(1U << REPORTED_BIT))
 42#endif
 43
 44#define VALUE_LENGTH 40
 45
 46static bool was_reported(struct source_location *location)
 47{
 48	return test_and_set_bit(REPORTED_BIT, &location->reported);
 49}
 50
 51static void print_source_location(const char *prefix,
 52				struct source_location *loc)
 53{
 54	pr_err("%s %s:%d:%d\n", prefix, loc->file_name,
 55		loc->line & LINE_MASK, loc->column & COLUMN_MASK);
 56}
 57
 58static bool suppress_report(struct source_location *loc)
 59{
 60	return current->in_ubsan || was_reported(loc);
 61}
 62
 63static bool type_is_int(struct type_descriptor *type)
 64{
 65	return type->type_kind == type_kind_int;
 66}
 67
 68static bool type_is_signed(struct type_descriptor *type)
 69{
 70	WARN_ON(!type_is_int(type));
 71	return  type->type_info & 1;
 72}
 73
 74static unsigned type_bit_width(struct type_descriptor *type)
 75{
 76	return 1 << (type->type_info >> 1);
 77}
 78
 79static bool is_inline_int(struct type_descriptor *type)
 80{
 81	unsigned inline_bits = sizeof(unsigned long)*8;
 82	unsigned bits = type_bit_width(type);
 83
 84	WARN_ON(!type_is_int(type));
 85
 86	return bits <= inline_bits;
 87}
 88
 89static s_max get_signed_val(struct type_descriptor *type, unsigned long val)
 90{
 91	if (is_inline_int(type)) {
 92		unsigned extra_bits = sizeof(s_max)*8 - type_bit_width(type);
 93		return ((s_max)val) << extra_bits >> extra_bits;
 94	}
 95
 96	if (type_bit_width(type) == 64)
 97		return *(s64 *)val;
 98
 99	return *(s_max *)val;
100}
101
102static bool val_is_negative(struct type_descriptor *type, unsigned long val)
103{
104	return type_is_signed(type) && get_signed_val(type, val) < 0;
105}
106
107static u_max get_unsigned_val(struct type_descriptor *type, unsigned long val)
108{
109	if (is_inline_int(type))
110		return val;
111
112	if (type_bit_width(type) == 64)
113		return *(u64 *)val;
114
115	return *(u_max *)val;
116}
117
118static void val_to_string(char *str, size_t size, struct type_descriptor *type,
119	unsigned long value)
120{
121	if (type_is_int(type)) {
122		if (type_bit_width(type) == 128) {
123#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
124			u_max val = get_unsigned_val(type, value);
125
126			scnprintf(str, size, "0x%08x%08x%08x%08x",
127				(u32)(val >> 96),
128				(u32)(val >> 64),
129				(u32)(val >> 32),
130				(u32)(val));
131#else
132			WARN_ON(1);
133#endif
134		} else if (type_is_signed(type)) {
135			scnprintf(str, size, "%lld",
136				(s64)get_signed_val(type, value));
137		} else {
138			scnprintf(str, size, "%llu",
139				(u64)get_unsigned_val(type, value));
140		}
141	}
142}
143
144static bool location_is_valid(struct source_location *loc)
145{
146	return loc->file_name != NULL;
147}
148
149static DEFINE_SPINLOCK(report_lock);
150
151static void ubsan_prologue(struct source_location *location,
152			unsigned long *flags)
153{
154	current->in_ubsan++;
155	spin_lock_irqsave(&report_lock, *flags);
156
157	pr_err("========================================"
158		"========================================\n");
159	print_source_location("UBSAN: Undefined behaviour in", location);
160}
161
162static void ubsan_epilogue(unsigned long *flags)
163{
164	dump_stack();
165	pr_err("========================================"
166		"========================================\n");
167	spin_unlock_irqrestore(&report_lock, *flags);
168	current->in_ubsan--;
169}
170
171static void handle_overflow(struct overflow_data *data, unsigned long lhs,
172			unsigned long rhs, char op)
173{
174
175	struct type_descriptor *type = data->type;
176	unsigned long flags;
177	char lhs_val_str[VALUE_LENGTH];
178	char rhs_val_str[VALUE_LENGTH];
179
180	if (suppress_report(&data->location))
181		return;
182
183	ubsan_prologue(&data->location, &flags);
184
185	val_to_string(lhs_val_str, sizeof(lhs_val_str), type, lhs);
186	val_to_string(rhs_val_str, sizeof(rhs_val_str), type, rhs);
187	pr_err("%s integer overflow:\n",
188		type_is_signed(type) ? "signed" : "unsigned");
189	pr_err("%s %c %s cannot be represented in type %s\n",
190		lhs_val_str,
191		op,
192		rhs_val_str,
193		type->type_name);
194
195	ubsan_epilogue(&flags);
196}
197
198void __ubsan_handle_add_overflow(struct overflow_data *data,
199				unsigned long lhs,
200				unsigned long rhs)
201{
202
203	handle_overflow(data, lhs, rhs, '+');
204}
205EXPORT_SYMBOL(__ubsan_handle_add_overflow);
206
207void __ubsan_handle_sub_overflow(struct overflow_data *data,
208				unsigned long lhs,
209				unsigned long rhs)
210{
211	handle_overflow(data, lhs, rhs, '-');
212}
213EXPORT_SYMBOL(__ubsan_handle_sub_overflow);
214
215void __ubsan_handle_mul_overflow(struct overflow_data *data,
216				unsigned long lhs,
217				unsigned long rhs)
218{
219	handle_overflow(data, lhs, rhs, '*');
220}
221EXPORT_SYMBOL(__ubsan_handle_mul_overflow);
222
223void __ubsan_handle_negate_overflow(struct overflow_data *data,
224				unsigned long old_val)
225{
226	unsigned long flags;
227	char old_val_str[VALUE_LENGTH];
228
229	if (suppress_report(&data->location))
230		return;
231
232	ubsan_prologue(&data->location, &flags);
233
234	val_to_string(old_val_str, sizeof(old_val_str), data->type, old_val);
235
236	pr_err("negation of %s cannot be represented in type %s:\n",
237		old_val_str, data->type->type_name);
238
239	ubsan_epilogue(&flags);
240}
241EXPORT_SYMBOL(__ubsan_handle_negate_overflow);
242
243
244void __ubsan_handle_divrem_overflow(struct overflow_data *data,
245				unsigned long lhs,
246				unsigned long rhs)
247{
248	unsigned long flags;
249	char rhs_val_str[VALUE_LENGTH];
250
251	if (suppress_report(&data->location))
252		return;
253
254	ubsan_prologue(&data->location, &flags);
255
256	val_to_string(rhs_val_str, sizeof(rhs_val_str), data->type, rhs);
257
258	if (type_is_signed(data->type) && get_signed_val(data->type, rhs) == -1)
259		pr_err("division of %s by -1 cannot be represented in type %s\n",
260			rhs_val_str, data->type->type_name);
261	else
262		pr_err("division by zero\n");
263
264	ubsan_epilogue(&flags);
265}
266EXPORT_SYMBOL(__ubsan_handle_divrem_overflow);
267
268static void handle_null_ptr_deref(struct type_mismatch_data *data)
269{
270	unsigned long flags;
271
272	if (suppress_report(&data->location))
273		return;
274
275	ubsan_prologue(&data->location, &flags);
276
277	pr_err("%s null pointer of type %s\n",
278		type_check_kinds[data->type_check_kind],
279		data->type->type_name);
280
281	ubsan_epilogue(&flags);
282}
283
284static void handle_missaligned_access(struct type_mismatch_data *data,
285				unsigned long ptr)
286{
287	unsigned long flags;
288
289	if (suppress_report(&data->location))
290		return;
291
292	ubsan_prologue(&data->location, &flags);
293
294	pr_err("%s misaligned address %p for type %s\n",
295		type_check_kinds[data->type_check_kind],
296		(void *)ptr, data->type->type_name);
297	pr_err("which requires %ld byte alignment\n", data->alignment);
298
299	ubsan_epilogue(&flags);
300}
301
302static void handle_object_size_mismatch(struct type_mismatch_data *data,
303					unsigned long ptr)
304{
305	unsigned long flags;
306
307	if (suppress_report(&data->location))
308		return;
309
310	ubsan_prologue(&data->location, &flags);
311	pr_err("%s address %p with insufficient space\n",
312		type_check_kinds[data->type_check_kind],
313		(void *) ptr);
314	pr_err("for an object of type %s\n", data->type->type_name);
315	ubsan_epilogue(&flags);
316}
317
318void __ubsan_handle_type_mismatch(struct type_mismatch_data *data,
319				unsigned long ptr)
320{
321
322	if (!ptr)
323		handle_null_ptr_deref(data);
324	else if (data->alignment && !IS_ALIGNED(ptr, data->alignment))
325		handle_missaligned_access(data, ptr);
326	else
327		handle_object_size_mismatch(data, ptr);
328}
329EXPORT_SYMBOL(__ubsan_handle_type_mismatch);
330
331void __ubsan_handle_nonnull_return(struct nonnull_return_data *data)
332{
333	unsigned long flags;
334
335	if (suppress_report(&data->location))
336		return;
337
338	ubsan_prologue(&data->location, &flags);
339
340	pr_err("null pointer returned from function declared to never return null\n");
341
342	if (location_is_valid(&data->attr_location))
343		print_source_location("returns_nonnull attribute specified in",
344				&data->attr_location);
345
346	ubsan_epilogue(&flags);
347}
348EXPORT_SYMBOL(__ubsan_handle_nonnull_return);
349
350void __ubsan_handle_vla_bound_not_positive(struct vla_bound_data *data,
351					unsigned long bound)
352{
353	unsigned long flags;
354	char bound_str[VALUE_LENGTH];
355
356	if (suppress_report(&data->location))
357		return;
358
359	ubsan_prologue(&data->location, &flags);
360
361	val_to_string(bound_str, sizeof(bound_str), data->type, bound);
362	pr_err("variable length array bound value %s <= 0\n", bound_str);
363
364	ubsan_epilogue(&flags);
365}
366EXPORT_SYMBOL(__ubsan_handle_vla_bound_not_positive);
367
368void __ubsan_handle_out_of_bounds(struct out_of_bounds_data *data,
369				unsigned long index)
370{
371	unsigned long flags;
372	char index_str[VALUE_LENGTH];
373
374	if (suppress_report(&data->location))
375		return;
376
377	ubsan_prologue(&data->location, &flags);
378
379	val_to_string(index_str, sizeof(index_str), data->index_type, index);
380	pr_err("index %s is out of range for type %s\n", index_str,
381		data->array_type->type_name);
382	ubsan_epilogue(&flags);
383}
384EXPORT_SYMBOL(__ubsan_handle_out_of_bounds);
385
386void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *data,
387					unsigned long lhs, unsigned long rhs)
388{
389	unsigned long flags;
390	struct type_descriptor *rhs_type = data->rhs_type;
391	struct type_descriptor *lhs_type = data->lhs_type;
392	char rhs_str[VALUE_LENGTH];
393	char lhs_str[VALUE_LENGTH];
394
395	if (suppress_report(&data->location))
396		return;
397
398	ubsan_prologue(&data->location, &flags);
399
400	val_to_string(rhs_str, sizeof(rhs_str), rhs_type, rhs);
401	val_to_string(lhs_str, sizeof(lhs_str), lhs_type, lhs);
402
403	if (val_is_negative(rhs_type, rhs))
404		pr_err("shift exponent %s is negative\n", rhs_str);
405
406	else if (get_unsigned_val(rhs_type, rhs) >=
407		type_bit_width(lhs_type))
408		pr_err("shift exponent %s is too large for %u-bit type %s\n",
409			rhs_str,
410			type_bit_width(lhs_type),
411			lhs_type->type_name);
412	else if (val_is_negative(lhs_type, lhs))
413		pr_err("left shift of negative value %s\n",
414			lhs_str);
415	else
416		pr_err("left shift of %s by %s places cannot be"
417			" represented in type %s\n",
418			lhs_str, rhs_str,
419			lhs_type->type_name);
420
421	ubsan_epilogue(&flags);
422}
423EXPORT_SYMBOL(__ubsan_handle_shift_out_of_bounds);
424
425
426void __noreturn
427__ubsan_handle_builtin_unreachable(struct unreachable_data *data)
428{
429	unsigned long flags;
430
431	ubsan_prologue(&data->location, &flags);
432	pr_err("calling __builtin_unreachable()\n");
433	ubsan_epilogue(&flags);
434	panic("can't return from __builtin_unreachable()");
435}
436EXPORT_SYMBOL(__ubsan_handle_builtin_unreachable);
437
438void __ubsan_handle_load_invalid_value(struct invalid_value_data *data,
439				unsigned long val)
440{
441	unsigned long flags;
442	char val_str[VALUE_LENGTH];
443
444	if (suppress_report(&data->location))
445		return;
446
447	ubsan_prologue(&data->location, &flags);
448
449	val_to_string(val_str, sizeof(val_str), data->type, val);
450
451	pr_err("load of value %s is not a valid value for type %s\n",
452		val_str, data->type->type_name);
453
454	ubsan_epilogue(&flags);
455}
456EXPORT_SYMBOL(__ubsan_handle_load_invalid_value);