Commit ed6fe9d6 authored Sep 01, 2012 by Mikulas Patocka Committed by Linus Torvalds Sep 05, 2012

Fix order of arguments to compat_put_time[spec|val]



Commit 644595f8 ("compat: Handle COMPAT_USE_64BIT_TIME in
net/socket.c") introduced a bug where the helper functions to take
either a 64-bit or compat time[spec|val] got the arguments in the wrong
order, passing the kernel stack pointer off as a user pointer (and vice
versa).

Because of the user address range check, that in turn then causes an
EFAULT due to the user pointer range checking failing for the kernel
address.  Incorrectly resuling in a failed system call for 32-bit
processes with a 64-bit kernel.

On odder architectures like HP-PA (with separate user/kernel address
spaces), it can be used read kernel memory.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 5b716ac7

net/socket.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -2604,7 +2604,7 @@ static int do_siocgstamp(struct net net, struct socket sock,
		err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
		set_fs(old_fs);
		if (!err)
		err = compat_put_timeval(up, &ktv);
		err = compat_put_timeval(&ktv, up);

		return err;
		}
		@@ -2620,7 +2620,7 @@ static int do_siocgstampns(struct net net, struct socket sock,
		err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
		set_fs(old_fs);
		if (!err)
		err = compat_put_timespec(up, &kts);
		err = compat_put_timespec(&kts, up);

		return err;
		}

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