From d19d0157edd69a18f5bf77aac4d614f2a831b6b5 Mon Sep 17 00:00:00 2001 From: Vinicius Costa Gomes Date: Mon, 21 Apr 2025 10:03:37 -0700 Subject: [PATCH] dmaengine: idxd: Fix allowing write() from different address spaces [ Upstream commit 8dfa57aabff625bf445548257f7711ef294cd30e ] Check if the process submitting the descriptor belongs to the same address space as the one that opened the file, reject otherwise. Fixes: 6827738dc684 ("dmaengine: idxd: add a write() method for applications to submit work") Signed-off-by: Vinicius Costa Gomes Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/20250421170337.3008875-1-dave.jiang@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/idxd/cdev.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c index c7aa47f01df0..186f005bfa8f 100644 --- a/drivers/dma/idxd/cdev.c +++ b/drivers/dma/idxd/cdev.c @@ -240,6 +240,9 @@ static int idxd_cdev_mmap(struct file *filp, struct vm_area_struct *vma) if (!idxd->user_submission_safe && !capable(CAP_SYS_RAWIO)) return -EPERM; + if (current->mm != ctx->mm) + return -EPERM; + rc = check_vma(wq, vma, __func__); if (rc < 0) return rc; @@ -306,6 +309,9 @@ static ssize_t idxd_cdev_write(struct file *filp, const char __user *buf, size_t ssize_t written = 0; int i; + if (current->mm != ctx->mm) + return -EPERM; + for (i = 0; i < len/sizeof(struct dsa_hw_desc); i++) { int rc = idxd_submit_user_descriptor(ctx, udesc + i); @@ -326,6 +332,9 @@ static __poll_t idxd_cdev_poll(struct file *filp, struct idxd_device *idxd = wq->idxd; __poll_t out = 0; + if (current->mm != ctx->mm) + return -EPERM; + poll_wait(filp, &wq->err_queue, wait); spin_lock(&idxd->dev_lock); if (idxd->sw_err.valid)