dma-buf: Proactively round up to kmalloc bucket size
Subsystems (2)
PATCH v3 1/1 dma-buf: Proactively round up to kmalloc bucket size
Instead of discovering the kmalloc bucket size _after_ allocation, round up proactively so the allocation is explicitly made for the full size, allowing the compiler to correctly reason about the resulting size of the buffer through the existing __alloc_size() hint.
Cc Sumit Semwal <[email protected]>
Reviewed-by Christian König <[email protected]>
Signed-off-by Kees Cook <[email protected]>
---
v3: added reviewed-by, rebase to v6.1-rc1
v2: https://lore.kernel.org/lkml/[email protected]/
--- drivers/dma-buf/dma-resv.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
drivers/dma-buf/dma-resv.c +7 -2
@@ -98,12 +98,17 @@ static void dma_resv_list_set(struct dma_resv_list *list,static struct dma_resv_list *dma_resv_list_alloc (unsigned int max_fences) {struct dma_resv_list *list; +size_t size; - list =kmalloc (struct_size (list, table, max_fences),GFP_KERNEL ); +/* Round up to the next kmalloc bucket size. */ + size =kmalloc_size_roundup (struct_size (list, table, max_fences)); + + list =kmalloc (size,GFP_KERNEL );if (!list)return NULL ; - list->max_fences = (ksize(list) - offsetof(typeof(*list), table)) / +/* Given the resulting bucket size, recalculated max_fences. */ + list->max_fences = (size - offsetof(typeof(*list), table)) /sizeof (*list->table);return list;
Signature · 1 line
2.34.1