+ drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory.patch added to -mm tree

+ drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory.patch added to -mm tree

[akpm]

The patch titled
     drivers/char/amiserial.c: prevent reading uninitialized stack memory
has been added to the -mm tree.  Its filename is
     drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory.patch

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See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: drivers/char/amiserial.c: prevent reading uninitialized stack memory
From: Dan Rosenberg <drosenberg@vsecurity.com>

The TIOCGICOUNT device ioctl allows unprivileged users to read
uninitialized stack memory, because the "reserved" member of the
serial_icounter_struct struct declared on the stack is not altered or
zeroed before being copied back to the user.  This patch takes care of it.

Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/char/amiserial.c |    3 +++
 1 file changed, 3 insertions(+)

diff -puN drivers/char/amiserial.c~drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory drivers/char/amiserial.c
--- a/drivers/char/amiserial.c~drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory
+++ a/drivers/char/amiserial.c
@@ -1342,6 +1342,9 @@ static int rs_ioctl(struct tty_struct *t
 			local_irq_save(flags);
 			cnow = info->state->icount;
 			local_irq_restore(flags);
+
+			memset(&icount, 0, sizeof(struct serial_icounter_struct));
+
 			icount.cts = cnow.cts;
 			icount.dsr = cnow.dsr;
 			icount.rng = cnow.rng;
_

Patches currently in -mm which might be from drosenberg@vsecurity.com are

linux-next.patch
drivers-serial-serial_corec-prevent-reading-uninitialized-stack-memory.patch
drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory.patch