| Message ID | 20240210141913.6611-1-erick.archer@gmx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/xe: Prefer struct_size over open coded arithmetic | expand |
On 2/10/24 08:19, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > As the "q" variable is a pointer to "struct xe_exec_queue" and this > structure ends in a flexible array: > > struct xe_exec_queue { > [...] > struct xe_lrc lrc[]; > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + size * count" in the > kzalloc() function. > > This way, the code is more readable and more safer. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Link: https://github.com/KSPP/linux/issues/160 [2] > Signed-off-by: Erick Archer <erick.archer@gmx.com> LGTM: Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks!
On Sat, Feb 10, 2024 at 10:49:57AM -0600, Gustavo A. R. Silva wrote: > > >On 2/10/24 08:19, Erick Archer wrote: >>This is an effort to get rid of all multiplications from allocation >>functions in order to prevent integer overflows [1]. >> >>As the "q" variable is a pointer to "struct xe_exec_queue" and this >>structure ends in a flexible array: >> >>struct xe_exec_queue { >> [...] >> struct xe_lrc lrc[]; >>}; >> >>the preferred way in the kernel is to use the struct_size() helper to >>do the arithmetic instead of the argument "size + size * count" in the >>kzalloc() function. >> >>This way, the code is more readable and more safer. >> >>Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] >>Link: https://github.com/KSPP/linux/issues/160 [2] >>Signed-off-by: Erick Archer <erick.archer@gmx.com> > >LGTM: > >Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> applied to drm-xe-next. Thanks for the patch and review. Lucas De Marchi
diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c index bcfc4127c7c5..f4e53cbccd04 100644 --- a/drivers/gpu/drm/xe/xe_exec_queue.c +++ b/drivers/gpu/drm/xe/xe_exec_queue.c @@ -44,7 +44,7 @@ static struct xe_exec_queue *__xe_exec_queue_create(struct xe_device *xe, /* only kernel queues can be permanent */ XE_WARN_ON((flags & EXEC_QUEUE_FLAG_PERMANENT) && !(flags & EXEC_QUEUE_FLAG_KERNEL)); - q = kzalloc(sizeof(*q) + sizeof(struct xe_lrc) * width, GFP_KERNEL); + q = kzalloc(struct_size(q, lrc, width), GFP_KERNEL); if (!q) return ERR_PTR(-ENOMEM);
This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1]. As the "q" variable is a pointer to "struct xe_exec_queue" and this structure ends in a flexible array: struct xe_exec_queue { [...] struct xe_lrc lrc[]; }; the preferred way in the kernel is to use the struct_size() helper to do the arithmetic instead of the argument "size + size * count" in the kzalloc() function. This way, the code is more readable and more safer. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Link: https://github.com/KSPP/linux/issues/160 [2] Signed-off-by: Erick Archer <erick.archer@gmx.com> --- drivers/gpu/drm/xe/xe_exec_queue.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.25.1