Merge tag 'hardening-v7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linuxHEADmaster

Pull hardening updates from Kees Cook:

 - Provide kmalloc_obj*-style API for devm_kmalloc()

 - Improve seq_buf API for saner C String handling with several bug
   fixes along the way (Kees Cook, Bill Wendling)

 - Overflow helper readability improvements (Bill Wendling)

 - Unexport native_write_cr4() (Dennis Chen)

 - um: fix CONFIG_GCOV for built-in code (Johannes Berg)

 - Improve stackinit test coverage (Justin Stitt)

 - KMSAN: fix memset() when using fortify-source, again (Arnd Bergmann)

 - lkdtm: use kmalloc() instead of __get_free_page (Mahad Ibrahim)

 - signalfd: don't dequeue the forced fatal signals (Oleg Nesterov)

 - Fix randstruct to recognize new container_of() behavior

 - coccinelle: kmalloc_obj: Convert multi-byte integral allocations too

 - Fix a couple remaining allocation return type mismatches

* tag 'hardening-v7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (29 commits)
  overflow: Match arithmetic in both parts of __builtin_choose_expr
  lkdtm: Make UNSET_SMEP built-in-only and unexport native_write_cr4()
  extcon: realtek: Remove const from type_c_cfg allocation type
  coresight: cti: Add const to con_groups allocation type
  docs: core-api: Document the seq_buf API
  nvdimm: ndtest: Return the string length from flags_show()
  powerpc/papr_scm: Return the string length from the sysfs show functions
  seq_buf: Add seq_buf_init_append()
  bpf: Remove dead newline stripping from format_disasm_line()
  seq_buf: Add seq_buf_terminate()
  seq_buf: Add seq_buf_strlen()
  seq_buf: Clear what a writer did not claim when a seq_buf overflows
  seq_buf: Copy what fits when seq_buf_puts() and seq_buf_putmem() overflow
  scsi: lpfc: Print rx monitor records straight into the seq_buf
  seq_buf: Do not pop from an overflowed seq_buf
  seq_buf: Do not print an empty line from an overflowed seq_buf_do_printk()
  .get_maintainer.ignore: Add Kees Cook
  devres: Provide kmalloc_obj*-style API for devm_kmalloc
  mm: Move default_gfp() into gfp_types.h
  kunit/stackinit: Clean up XFAIL under instrumentation
  ...

1 files changed, 102 insertions, 0 deletions

diff --git a/include/linux/device/devres.h b/include/linux/device/devres.h
index 14ab9159bdda..7656c9ecd4da 100644
--- a/include/linux/device/devres.h
+++ b/include/linux/device/devres.h
@@ -62,6 +62,108 @@ static inline void *devm_kcalloc(struct device *dev, size_t n, size_t size, gfp_
 {
 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 }
+
+/**
+ * __devm_alloc_objs - Device-managed allocation of objects of a given type
+ * @DEVM_ALLOC: which device-managed size-based allocator to use.
+ * @DEV: device to scope the allocation lifetime to.
+ * @GFP: GFP flags for the allocation.
+ * @TYPE: type to allocate space for.
+ * @COUNT: how many @TYPE objects to allocate.
+ *
+ * Device-managed counterpart of __alloc_objs().
+ * @DEVM_ALLOC takes (@DEV, size, gfp).
+ *
+ * Returns: Newly allocated pointer to (first) @TYPE of @COUNT-many allocated
+ * @TYPE objects, or NULL on failure.
+ */
+#define __devm_alloc_objs(DEVM_ALLOC, DEV, GFP, TYPE, COUNT)		\
+({									\
+	const size_t __obj_size = size_mul(sizeof(TYPE), COUNT);	\
+	(TYPE *)DEVM_ALLOC(DEV, __obj_size, GFP);			\
+})
+
+/**
+ * devm_kmalloc_obj - Device-managed allocation of a single typed object
+ * @DEV: Device to scope the allocation lifetime to.
+ * @VAR_OR_TYPE: Variable or type to allocate.
+ * @GFP: Optional GFP flags (defaults to %GFP_KERNEL).
+ *
+ * Device-managed counterpart of kmalloc_obj(): the allocation is sized from
+ * @VAR_OR_TYPE and returned as a pointer to that type, not void *.
+ *
+ * Returns: newly allocated pointer to a @VAR_OR_TYPE on success, or NULL on
+ * failure.
+ */
+#define devm_kmalloc_obj(DEV, VAR_OR_TYPE, ...)				\
+	__devm_alloc_objs(devm_kmalloc, DEV, default_gfp(__VA_ARGS__),	\
+			  typeof(VAR_OR_TYPE), 1)
+
+/**
+ * devm_kmalloc_objs - Device-managed allocation of an array of a typed object
+ * @DEV: Device to scope the allocation lifetime to.
+ * @VAR_OR_TYPE: Variable or type to allocate an array of.
+ * @COUNT: How many elements in the array.
+ * @GFP: Optional GFP flags (defaults to %GFP_KERNEL).
+ *
+ * Returns: newly allocated pointer to an array of @VAR_OR_TYPE on success, or
+ * NULL on failure (including when the total size overflows).
+ */
+#define devm_kmalloc_objs(DEV, VAR_OR_TYPE, COUNT, ...) \
+	__devm_alloc_objs(devm_kmalloc, DEV, default_gfp(__VA_ARGS__), \
+			  typeof(VAR_OR_TYPE), COUNT)
+
+/**
+ * __devm_alloc_flex - Device-managed allocation of a trailing-flex-array object
+ * @DEVM_ALLOC: which device-managed allocator to use.
+ * @DEV: device to scope the allocation lifetime to.
+ * @GFP: GFP flags for the allocation.
+ * @TYPE: type of structure to allocate space for.
+ * @FAM: name of the flexible array member of @TYPE.
+ * @COUNT: how many @FAM elements to allocate space for.
+ *
+ * Device-managed counterpart of __alloc_flex().
+ * @DEVM_ALLOC takes (@DEV, size, gfp).
+ *
+ * Returns: Newly allocated pointer to @TYPE with @COUNT-many trailing @FAM
+ * elements, or NULL on failure.
+ */
+#define __devm_alloc_flex(DEVM_ALLOC, DEV, GFP, TYPE, FAM, COUNT)	\
+({									\
+	const size_t __count = (COUNT);					\
+	const size_t __obj_size = struct_size_t(TYPE, FAM, __count);	\
+	TYPE *__obj_ptr = DEVM_ALLOC(DEV, __obj_size, GFP);		\
+	if (__obj_ptr)							\
+		__set_flex_counter(__obj_ptr->FAM, __count);		\
+	__obj_ptr;							\
+})
+
+/**
+ * devm_kmalloc_flex - Device-managed allocation of a flexible-array structure
+ * @DEV: Device to scope the allocation lifetime to.
+ * @VAR_OR_TYPE: Variable or type to allocate (with its flexible array).
+ * @FAM: The name of the flexible array member of the structure.
+ * @COUNT: How many flexible array member elements to allocate.
+ * @GFP: Optional GFP flags (defaults to %GFP_KERNEL).
+ *
+ * Returns: newly allocated pointer to @VAR_OR_TYPE on success, or NULL on
+ * failure. If @FAM has been annotated with __counted_by(), its counter is set
+ * to @COUNT.
+ */
+#define devm_kmalloc_flex(DEV, VAR_OR_TYPE, FAM, COUNT, ...) \
+	__devm_alloc_flex(devm_kmalloc, DEV, default_gfp(__VA_ARGS__), \
+			  typeof(VAR_OR_TYPE), FAM, COUNT)
+
+/* All devm_kzalloc aliases for devm_kmalloc_(obj|objs|flex). */
+#define devm_kzalloc_obj(DEV, P, ...) \
+	__devm_alloc_objs(devm_kzalloc, DEV, default_gfp(__VA_ARGS__), typeof(P), 1)
+#define devm_kzalloc_objs(DEV, P, COUNT, ...) \
+	__devm_alloc_objs(devm_kzalloc, DEV, default_gfp(__VA_ARGS__), \
+			  typeof(P), COUNT)
+#define devm_kzalloc_flex(DEV, P, FAM, COUNT, ...) \
+	__devm_alloc_flex(devm_kzalloc, DEV, default_gfp(__VA_ARGS__), \
+			  typeof(P), FAM, COUNT)
+
 static inline __realloc_size(3, 4) void * __must_check
 devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
 {