a7bc830b76
[ Upstream commit 09279e615c81ce55e04835970601ae286e3facbe ]
Syzbot report a kernel-infoleak:
BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
Call Trace:
_copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
copy_to_user include/linux/uaccess.h:174 [inline]
sctp_getsockopt_peer_addrs net/sctp/socket.c:5911 [inline]
sctp_getsockopt+0x1668e/0x17f70 net/sctp/socket.c:7562
...
Uninit was stored to memory at:
sctp_transport_init net/sctp/transport.c:61 [inline]
sctp_transport_new+0x16d/0x9a0 net/sctp/transport.c:115
sctp_assoc_add_peer+0x532/0x1f70 net/sctp/associola.c:637
sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline]
sctp_process_init+0x1a1b/0x3ed0 net/sctp/sm_make_chunk.c:2361
...
Bytes 8-15 of 16 are uninitialized
It was caused by that th _pad field (the 8-15 bytes) of a v4 addr (saved in
struct sockaddr_in) wasn't initialized, but directly copied to user memory
in sctp_getsockopt_peer_addrs().
So fix it by calling memset(addr->v4.sin_zero, 0, 8) to initialize _pad of
sockaddr_in before copying it to user memory in sctp_v4_addr_to_user(), as
sctp_v6_addr_to_user() does.
Reported-by: syzbot+86b5c7c236a22616a72f@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Tested-by: Alexander Potapenko <glider@google.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.