From a5bff92eaac45bdf6221badf9505c26792fdf99e Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Tue, 7 Apr 2020 15:30:02 +0200 Subject: [PATCH] dma-buf: Fix SET_NAME ioctl uapi The uapi is the same on 32 and 64 bit, but the number isn't. Everyone who botched this please re-read: https://www.kernel.org/doc/html/v5.4-preprc-cpu/ioctl/botching-up-ioctls.html Also, the type argument for the ioctl macros is for the type the void __user *arg pointer points at, which in this case would be the variable-sized char[] of a 0 terminated string. So this was botched in more than just the usual ways. Cc: Sumit Semwal Cc: Chenbo Feng Cc: Greg Hackmann Cc: Daniel Vetter Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: minchan@kernel.org Cc: surenb@google.com Cc: jenhaochen@google.com Cc: Martin Liu Signed-off-by: Daniel Vetter Tested-by: Martin Liu Reviewed-by: Martin Liu Signed-off-by: Sumit Semwal [sumits: updated some checkpatch fixes, corrected author email] Link: https://patchwork.freedesktop.org/patch/msgid/20200407133002.3486387-1-daniel.vetter@ffwll.ch --- drivers/dma-buf/dma-buf.c | 3 ++- include/uapi/linux/dma-buf.h | 6 ++++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index ccc9eda1bc28..de155d41d274 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -388,7 +388,8 @@ static long dma_buf_ioctl(struct file *file, return ret; - case DMA_BUF_SET_NAME: + case DMA_BUF_SET_NAME_A: + case DMA_BUF_SET_NAME_B: return dma_buf_set_name(dmabuf, (const char __user *)arg); default: diff --git a/include/uapi/linux/dma-buf.h b/include/uapi/linux/dma-buf.h index dbc7092e04b5..7f30393b92c3 100644 --- a/include/uapi/linux/dma-buf.h +++ b/include/uapi/linux/dma-buf.h @@ -39,6 +39,12 @@ struct dma_buf_sync { #define DMA_BUF_BASE 'b' #define DMA_BUF_IOCTL_SYNC _IOW(DMA_BUF_BASE, 0, struct dma_buf_sync) + +/* 32/64bitness of this uapi was botched in android, there's no difference + * between them in actual uapi, they're just different numbers. + */ #define DMA_BUF_SET_NAME _IOW(DMA_BUF_BASE, 1, const char *) +#define DMA_BUF_SET_NAME_A _IOW(DMA_BUF_BASE, 1, u32) +#define DMA_BUF_SET_NAME_B _IOW(DMA_BUF_BASE, 1, u64) #endif -- 2.39.5