This is a note to let you know that I've just added the patch titled
/dev/mem: Avoid overwriting "err" in read_mem()
to the 4.14-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:
dev-mem-avoid-overwriting-err-in-read_mem.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b5b38200ebe54879a7264cb6f33821f61c586a7e Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@xxxxxxxxxxxx>
Date: Tue, 27 Mar 2018 14:06:14 -0700
Subject: /dev/mem: Avoid overwriting "err" in read_mem()
From: Kees Cook <keescook@xxxxxxxxxxxx>
commit b5b38200ebe54879a7264cb6f33821f61c586a7e upstream.
Successes in probe_kernel_read() would mask failures in copy_to_user()
during read_mem().
Reported-by: Brad Spengler <spender@xxxxxxxxxxxxxx>
Fixes: 22ec1a2aea73 ("/dev/mem: Add bounce buffer for copy-out")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/mem.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -137,7 +137,7 @@ static ssize_t read_mem(struct file *fil
while (count > 0) {
unsigned long remaining;
- int allowed;
+ int allowed, probe;
sz = size_inside_page(p, count);
@@ -160,9 +160,9 @@ static ssize_t read_mem(struct file *fil
if (!ptr)
goto failed;
- err = probe_kernel_read(bounce, ptr, sz);
+ probe = probe_kernel_read(bounce, ptr, sz);
unxlate_dev_mem_ptr(p, ptr);
- if (err)
+ if (probe)
goto failed;
remaining = copy_to_user(buf, bounce, sz);
Patches currently in stable-queue which might be from keescook@xxxxxxxxxxxx are
queue-4.14/dev-mem-avoid-overwriting-err-in-read_mem.patch