From 0510cb5b23037dbaaf57b8ddd6af32cbfc173ef2 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V (Arm)" Date: Fri, 17 Jul 2026 23:34:20 +0530 Subject: [PATCH] dma-pool: fix page leak in atomic_pool_expand() cleanup atomic_pool_expand() frees the allocated pages from the remove_mapping error path only when CONFIG_DMA_DIRECT_REMAP is enabled. When CONFIG_DMA_DIRECT_REMAP is disabled, failures after page allocation, such as gen_pool_add_virt(), jump to remove_mapping and return without freeing the pages. Move __free_pages(page, order) out of the CONFIG_DMA_DIRECT_REMAP block so that cleanup paths always release the allocation. Reviewed-by: Jason Gunthorpe Tested-by: Michael Kelley Tested-by: Mostafa Saleh Signed-off-by: Aneesh Kumar K.V (Arm) Link: https://lore.kernel.org/r/20260717180442.110954-3-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski --- kernel/dma/pool.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 2b2fbb709242..b0303efbc153 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -81,6 +81,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, { unsigned int order; struct page *page = NULL; + bool leak_pages = false; void *addr; int ret = -ENOMEM; @@ -115,8 +116,10 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, */ ret = set_memory_decrypted((unsigned long)page_to_virt(page), 1 << order); - if (ret) + if (ret) { + leak_pages = true; goto remove_mapping; + } ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page), pool_size, NUMA_NO_NODE); if (ret) @@ -130,14 +133,15 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, 1 << order); if (WARN_ON_ONCE(ret)) { /* Decrypt succeeded but encrypt failed, purposely leak */ - goto out; + leak_pages = true; } remove_mapping: #ifdef CONFIG_DMA_DIRECT_REMAP dma_common_free_remap(addr, pool_size); free_page: - __free_pages(page, order); #endif + if (!leak_pages) + __free_pages(page, order); out: return ret; }