From 84909f7decbd8981a24be829f110c248ecb8c51a Mon Sep 17 00:00:00 2001 From: Nilay Shroff Date: Sun, 24 Nov 2024 18:25:53 +0530 Subject: [PATCH] nvmet: use kzalloc instead of ZERO_PAGE in nvme_execute_identify_ns_nvm() The nvme_execute_identify_ns_nvm function uses ZERO_PAGE for copying SG list with all zeros. As ZERO_PAGE would not necessarily return the virtual-address of the zero page, we need to first convert the page address to kernel virtual-address and then use it as source address for copying the data to SG list with all zeros. Using return address of ZERO_PAGE(0) as source address for copying data to SG list would fill the target buffer with random/garbage value and causes the undesired side effect. As other identify implemenations uses kzalloc for allocating a zero filled buffer, we decided use kzalloc for allocating a zero filled buffer in nvme_execute_identify_ns_nvm function and then use this buffer for copying all zeros to SG list buffers. So esentially, we now avoid using ZERO_PAGE. Reported-by: Yi Zhang Fixes: 64a51080eaba ("nvmet: implement id ns for nvm command set") Link: https://lore.kernel.org/all/CAHj4cs8OVyxmn4XTvA=y4uQ3qWpdw-x3M3FSUYr-KpE-nhaFEA@mail.gmail.com/ Signed-off-by: Nilay Shroff Tested-by: Yi Zhang Reviewed-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni Signed-off-by: Keith Busch --- drivers/nvme/target/admin-cmd.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c index 4fa8496a4d96..2962794ce881 100644 --- a/drivers/nvme/target/admin-cmd.c +++ b/drivers/nvme/target/admin-cmd.c @@ -902,13 +902,18 @@ static void nvmet_execute_identify_ctrl_nvm(struct nvmet_req *req) static void nvme_execute_identify_ns_nvm(struct nvmet_req *req) { u16 status; + struct nvme_id_ns_nvm *id; status = nvmet_req_find_ns(req); if (status) goto out; - status = nvmet_copy_to_sgl(req, 0, ZERO_PAGE(0), - NVME_IDENTIFY_DATA_SIZE); + id = kzalloc(sizeof(*id), GFP_KERNEL); + if (!id) { + status = NVME_SC_INTERNAL; + goto out; + } + status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id)); out: nvmet_req_complete(req, status); }