From 621707dc67c9846fd876d7579ec951d92aa033f1 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nuno=20S=C3=A1?= Date: Fri, 12 Jun 2026 15:57:57 +0100 Subject: [PATCH] usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The error paths for endpoint-disabled (ESHUTDOWN) and request-allocation failure (ENOMEM) in ffs_dmabuf_transfer() jump to err_fence_put which calls dma_fence_put() on the fence. However, at that point the fence has only been kmalloc'd — dma_fence_init() has not been called yet, so the refcount and the fence ops are uninitialized. Calling dma_fence_put() on such an object leads to undefined behavior. Use kfree() instead, since the fence is just a plain allocation at this stage, and rename the label to err_fence_free to reflect the actual cleanup action. Fixes: 7b07a2a7ca02 ("usb: gadget: functionfs: Add DMABUF import interface") Signed-off-by: Nuno Sá Reviewed-by: Paul Cercueil Link: https://patch.msgid.link/20260612-fix-f_fs-fence-cleanup-v1-1-79f489b0efe9@analog.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_fs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 75912ce6ab55..ac8c53789ec2 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1682,13 +1682,13 @@ static int ffs_dmabuf_transfer(struct file *file, /* In the meantime, endpoint got disabled or changed. */ if (epfile->ep != ep) { ret = -ESHUTDOWN; - goto err_fence_put; + goto err_fence_free; } usb_req = usb_ep_alloc_request(ep->ep, GFP_ATOMIC); if (!usb_req) { ret = -ENOMEM; - goto err_fence_put; + goto err_fence_free; } /* @@ -1736,9 +1736,9 @@ static int ffs_dmabuf_transfer(struct file *file, return ret; -err_fence_put: +err_fence_free: spin_unlock_irq(&epfile->ffs->eps_lock); - dma_fence_put(&fence->base); + kfree(fence); err_resv_unlock: dma_resv_unlock(dmabuf->resv); err_attachment_put: