[v2] driver core: Add __alloc_size hint to devm allocators
Commit Message
Mark the devm_*alloc()-family of allocations with appropriate
__alloc_size()/__realloc_size() hints so the compiler can attempt to
reason about buffer lengths from allocations.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Nishanth Menon <nm@ti.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Won Chung <wonchung@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
I'm hoping to carry this via the hardening tree so I can add a
KUnit test that depends on it...
v2: use __realloc_size instead of __alloc_size
v1: https://lore.kernel.org/linux-hardening/20221018073430.never.551-kees@kernel.org/
---
include/linux/device.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Comments
On Sat, Oct 29, 2022 at 12:47:34AM -0700, Kees Cook wrote:
> Mark the devm_*alloc()-family of allocations with appropriate
> __alloc_size()/__realloc_size() hints so the compiler can attempt to
> reason about buffer lengths from allocations.
>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason Gunthorpe <jgg@ziepe.ca>
> Cc: Nishanth Menon <nm@ti.com>
> Cc: Michael Kelley <mikelley@microsoft.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Cc: Won Chung <wonchung@google.com>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
> I'm hoping to carry this via the hardening tree so I can add a
> KUnit test that depends on it...
> v2: use __realloc_size instead of __alloc_size
> v1: https://lore.kernel.org/linux-hardening/20221018073430.never.551-kees@kernel.org/
> ---
> include/linux/device.h | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
@@ -197,9 +197,9 @@ void devres_remove_group(struct device *dev, void *id);
int devres_release_group(struct device *dev, void *id);
/* managed devm_k.alloc/kfree for device drivers */
-void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
+void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __alloc_size(2);
void *devm_krealloc(struct device *dev, void *ptr, size_t size,
- gfp_t gfp) __must_check;
+ gfp_t gfp) __must_check __realloc_size(3);
__printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
const char *fmt, va_list ap) __malloc;
__printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
@@ -226,7 +226,8 @@ static inline void *devm_kcalloc(struct device *dev,
void devm_kfree(struct device *dev, const void *p);
char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
-void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp);
+void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp)
+ __realloc_size(3);
unsigned long devm_get_free_pages(struct device *dev,
gfp_t gfp_mask, unsigned int order);