diff options
| author | Gustavo A. R. Silva <gustavoars@kernel.org> | 2020-07-20 10:31:19 -0700 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2020-07-27 14:55:42 +0200 |
| commit | 10cfde5dc695856c4fe93f0679d2fdd8e0d2a147 (patch) | |
| tree | 49fef4c18607bd775cc027f0c202b8bf9e6b917d /include/acpi | |
| parent | 92ed301919932f777713b9172e525674157e983d (diff) | |
ACPICA: Replace one-element array with flexible-array
ACPICA commit 7ba2f3d91a32f104765961fda0ed78b884ae193d
The current codebase makes use of one-element arrays in the following
form:
struct something {
int length;
u8 data[1];
};
struct something *instance;
instance = kmalloc(sizeof(*instance) + size, GFP_KERNEL);
instance->length = size;
memcpy(instance->data, source, size);
but the preferred mechanism to declare variable-length types such as
these ones is a flexible array member[1][2], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure,
which will help us prevent some kind of undefined behavior bugs from
being inadvertently introduced[3] to the linux codebase from now on.
This issue was found with the help of Coccinelle and audited _manually_.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Link: https://github.com/acpica/acpica/commit/7ba2f3d9
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Erik Kaneda <erik.kaneda@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'include/acpi')
| -rw-r--r-- | include/acpi/actypes.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index aa236b9e6f24..735921c833f8 100644 --- a/include/acpi/actypes.h +++ b/include/acpi/actypes.h @@ -1146,7 +1146,7 @@ struct acpi_pnp_device_id { struct acpi_pnp_device_id_list { u32 count; /* Number of IDs in Ids array */ u32 list_size; /* Size of list, including ID strings */ - struct acpi_pnp_device_id ids[1]; /* ID array */ + struct acpi_pnp_device_id ids[]; /* ID array */ }; /* |