From 67801fa67b94ebd0e4da7a77ac2d9f321b75fbe0 Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Wed, 25 Sep 2024 08:14:28 +0100 Subject: drm/xe/queue: move xa_alloc to prevent UAF Evil user can guess the next id of the queue before the ioctl completes and then call queue destroy ioctl to trigger UAF since create ioctl is still referencing the same queue. Move the xa_alloc all the way to the end to prevent this. v2: - Rebase Fixes: 2149ded63079 ("drm/xe: Fix use after free when client stats are captured") Signed-off-by: Matthew Auld Cc: Matthew Brost Reviewed-by: Nirmoy Das Reviewed-by: Matthew Brost Link: https://patchwork.freedesktop.org/patch/msgid/20240925071426.144015-4-matthew.auld@intel.com (cherry picked from commit 16536582ddbebdbdf9e1d7af321bbba2bf955a87) Signed-off-by: Lucas De Marchi --- drivers/gpu/drm/xe/xe_exec_queue.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c index 7743ebdcbf4b..d098d2dd1b2d 100644 --- a/drivers/gpu/drm/xe/xe_exec_queue.c +++ b/drivers/gpu/drm/xe/xe_exec_queue.c @@ -635,12 +635,14 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data, } } + q->xef = xe_file_get(xef); + + /* user id alloc must always be last in ioctl to prevent UAF */ err = xa_alloc(&xef->exec_queue.xa, &id, q, xa_limit_32b, GFP_KERNEL); if (err) goto kill_exec_queue; args->exec_queue_id = id; - q->xef = xe_file_get(xef); return 0; -- cgit v1.2.3-58-ga151