From 8c0fd126263730c35927cc8445727afb79219a19 Mon Sep 17 00:00:00 2001 From: Guangming Cao Date: Fri, 8 Oct 2021 15:54:20 +0800 Subject: dma-buf: acquire name lock before read/write dma_buf.name MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Because dma-buf.name can be freed in func: "dma_buf_set_name", so, we need to acquire lock first before we read/write dma_buf.name to prevent Use After Free(UAF) issue. Signed-off-by: Guangming Cao Reviewed-by: Christian König Signed-off-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/20211008075420.42874-1-guangming.cao@mediatek.com --- drivers/dma-buf/dma-buf.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 63d32261b63f..92492e314bd9 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1389,6 +1389,8 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) if (ret) goto error_unlock; + + spin_lock(&buf_obj->name_lock); seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\t%s\n", buf_obj->size, buf_obj->file->f_flags, buf_obj->file->f_mode, @@ -1396,6 +1398,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) buf_obj->exp_name, file_inode(buf_obj->file)->i_ino, buf_obj->name ?: ""); + spin_unlock(&buf_obj->name_lock); robj = buf_obj->resv; fence = dma_resv_excl_fence(robj); -- cgit