This is a note to let you know that I've just added the patch titled
misc: genwqe: check for error from get_user_pages_fast()
to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
misc-genwqe-check-for-error-from-get_user_pages_fast.patch
and it can be found in the queue-3.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cf35d6e0475982667b0d2d318fb27be4b8849827 Mon Sep 17 00:00:00 2001
From: Ian Abbott <abbotti@xxxxxxxxx>
Date: Thu, 6 Nov 2014 16:23:39 +0000
Subject: misc: genwqe: check for error from get_user_pages_fast()
From: Ian Abbott <abbotti@xxxxxxxxx>
commit cf35d6e0475982667b0d2d318fb27be4b8849827 upstream.
`genwqe_user_vmap()` calls `get_user_pages_fast()` and if the return
value is less than the number of pages requested, it frees the pages and
returns an error (`-EFAULT`). However, it fails to consider a negative
error return value from `get_user_pages_fast()`. In that case, the test
`if (rc < m->nr_pages)` will be false (due to promotion of `rc` to a
large `unsigned int`) and the code will continue on to call
`genwqe_map_pages()` with an invalid list of page pointers. Fix it by
bailing out if `get_user_pages_fast()` returns a negative error value.
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/genwqe/card_utils.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/misc/genwqe/card_utils.c
+++ b/drivers/misc/genwqe/card_utils.c
@@ -490,6 +490,8 @@ int genwqe_user_vmap(struct genwqe_dev *
m->nr_pages,
1, /* write by caller */
m->page_list); /* ptrs to pages */
+ if (rc < 0)
+ goto fail_get_user_pages;
/* assumption: get_user_pages can be killed by signals. */
if (rc < m->nr_pages) {
Patches currently in stable-queue which might be from abbotti@xxxxxxxxx are
queue-3.14/misc-genwqe-check-for-error-from-get_user_pages_fast.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html