From dea5d380e22c1bd754cd3f02ac75ca544b4f656e Mon Sep 17 00:00:00 2001 From: Roberto Bergantinos Corpas Date: Tue, 28 May 2019 09:38:14 +0200 Subject: [PATCH] CIFS: cifs_read_allocate_pages: don't iterate through whole page array on ENOMEM commit 31fad7d41e73731f05b8053d17078638cf850fa6 upstream. In cifs_read_allocate_pages, in case of ENOMEM, we go through whole rdata->pages array but we have failed the allocation before nr_pages, therefore we may end up calling put_page with NULL pointer, causing oops Signed-off-by: Roberto Bergantinos Corpas Acked-by: Pavel Shilovsky Signed-off-by: Steve French CC: Stable Signed-off-by: Greg Kroah-Hartman --- fs/cifs/file.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 48ea9dfd5f02..6ee8f9270892 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2984,7 +2984,9 @@ cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages) } if (rc) { - for (i = 0; i < nr_pages; i++) { + unsigned int nr_page_failed = i; + + for (i = 0; i < nr_page_failed; i++) { put_page(rdata->pages[i]); rdata->pages[i] = NULL; } -- 2.20.1