From 94e18007688a13e5da1a2f1b7f52f15cc56c9f5e Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Mon, 4 Mar 2013 15:18:25 -0500 Subject: [PATCH] cifs: don't try to unlock pagecache page after releasing it We had a recent fix to fix the release of pagecache pages when cifs_writev_requeue writes fail. Unfortunately, it releases the page before trying to unlock it. At that point, the page might be gone by the time the unlock comes in. Unlock the page first before checking the value of "rc", and only then end writeback and release the pages. The page lock isn't required for any of those operations so this should be safe. Reported-by: Anton Altaparmakov Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/cifssmb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 7353bc5d73d7..8e2e799e7a24 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -1909,12 +1909,12 @@ cifs_writev_requeue(struct cifs_writedata *wdata) } while (rc == -EAGAIN); for (i = 0; i < wdata->nr_pages; i++) { + unlock_page(wdata->pages[i]); if (rc != 0) { SetPageError(wdata->pages[i]); end_page_writeback(wdata->pages[i]); page_cache_release(wdata->pages[i]); } - unlock_page(wdata->pages[i]); } mapping_set_error(inode->i_mapping, rc); -- 2.20.1