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R. Silva" , linux-hardening@vger.kernel.org (open list:KERNEL HARDENING (not covered by other areas):Keyword:\b__counted_by(_le|_be)?\b) Subject: [PATCH] virt: nitro_enclaves: Use flexible array for memory pages Date: Sun, 10 May 2026 21:20:41 -0700 Message-ID: <20260511042041.378366-1-rosenp@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Store the per-region page pointers in the memory region allocation instead of allocating them separately. Keep the allocated page-pointer capacity separate from the number of pinned pages so __counted_by() describes the flexible array bounds while nr_pages continues to track pages that need to be released. Assisted-by: Codex:GPT-5.5 Signed-off-by: Rosen Penev --- drivers/virt/nitro_enclaves/ne_misc_dev.c | 15 ++------------- drivers/virt/nitro_enclaves/ne_misc_dev.h | 2 +- 2 files changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.c b/drivers/virt/nitro_enclaves/ne_misc_dev.c index c91300a73f50..c0045b2cf7f3 100644 --- a/drivers/virt/nitro_enclaves/ne_misc_dev.c +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c @@ -927,19 +927,11 @@ static int ne_set_user_memory_region_ioctl(struct ne_enclave *ne_enclave, if (rc < 0) return rc; - ne_mem_region = kzalloc_obj(*ne_mem_region); + max_nr_pages = mem_region.memory_size / NE_MIN_MEM_REGION_SIZE; + ne_mem_region = kzalloc_flex(*ne_mem_region, pages, max_nr_pages); if (!ne_mem_region) return -ENOMEM; - max_nr_pages = mem_region.memory_size / NE_MIN_MEM_REGION_SIZE; - - ne_mem_region->pages = kzalloc_objs(*ne_mem_region->pages, max_nr_pages); - if (!ne_mem_region->pages) { - rc = -ENOMEM; - - goto free_mem_region; - } - phys_contig_mem_regions.regions = kzalloc_objs(*phys_contig_mem_regions.regions, max_nr_pages); if (!phys_contig_mem_regions.regions) { @@ -1049,7 +1041,6 @@ static int ne_set_user_memory_region_ioctl(struct ne_enclave *ne_enclave, put_page(ne_mem_region->pages[i]); free_mem_region: kfree(phys_contig_mem_regions.regions); - kfree(ne_mem_region->pages); kfree(ne_mem_region); return rc; @@ -1398,8 +1389,6 @@ static void ne_enclave_remove_all_mem_region_entries(struct ne_enclave *ne_encla for (i = 0; i < ne_mem_region->nr_pages; i++) put_page(ne_mem_region->pages[i]); - kfree(ne_mem_region->pages); - kfree(ne_mem_region); } } diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.h b/drivers/virt/nitro_enclaves/ne_misc_dev.h index 2a4d2224baba..f419e04007f8 100644 --- a/drivers/virt/nitro_enclaves/ne_misc_dev.h +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.h @@ -28,8 +28,8 @@ struct ne_mem_region { struct list_head mem_region_list_entry; u64 memory_size; unsigned long nr_pages; - struct page **pages; u64 userspace_addr; + struct page *pages[]; }; /** -- 2.54.0