coccinelle: catch krealloc() on devm_*() allocated memory
krealloc() must not be used against devm_*() allocated
memory regions:
- if a bigger memory is to be allocated, krealloc() and
__krealloc() could return a different pointer than the
one given to them, creating a memory region which is not
managed, thus it will not be automatically released on
device removal.
- if a bigger memory is to be allocated, krealloc() could
kfree() the managed memory region which is passed to it.
The old pointer is left registered as a resource for the
device. On device removal, this dangling pointer will be
used and an unrelated memory region could be released.
- if the requested size is equal to 0, krealloc() can also
just behave like kfree(). Here too, the old pointer is
kept associated with the device. On device removal, this
invalid pointer will be used and an unrelated memory
region could be released.
For all these reasons, krealloc() must not be used on a
pointer returned by devm_*() functions.
Cc: Tejun Heo <tj@kernel.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
1 file changed