Messages in this thread Patch in this message | | | Date | Wed, 1 Sep 2021 21:57:18 +0300 | Subject | Re: [syzbot] UBSAN: shift-out-of-bounds in xfrm_get_default | From | Pavel Skripkin <> |
| |
On 9/1/21 21:56, syzbot wrote: >> On 8/30/21 23:19, syzbot wrote: >>> Hello, >>> >>> syzbot found the following issue on: >>> >>> HEAD commit: eaf2aaec0be4 Merge tag 'wireless-drivers-next-2021-08-29' .. >>> git tree: net-next >>> console output: https://syzkaller.appspot.com/x/log.txt?x=1219326d300000 >>> kernel config: https://syzkaller.appspot.com/x/.config?x=d2f9d4c9ff8c5ae7 >>> dashboard link: https://syzkaller.appspot.com/bug?extid=b2be9dd8ca6f6c73ee2d >>> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 >>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11e6e3a9300000 >>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10de8a6d300000 >>> >>> The issue was bisected to: >>> >>> commit 2d151d39073aff498358543801fca0f670fea981 >>> Author: Steffen Klassert <steffen.klassert@secunet.com> >>> Date: Sun Jul 18 07:11:06 2021 +0000 >>> >>> xfrm: Add possibility to set the default to block if we have no policy >>> >>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=114523fe300000 >>> final oops: https://syzkaller.appspot.com/x/report.txt?x=134523fe300000 >>> console output: https://syzkaller.appspot.com/x/log.txt?x=154523fe300000 >>> >>> IMPORTANT: if you fix the issue, please add the following tag to the commit: >>> Reported-by: syzbot+b2be9dd8ca6f6c73ee2d@syzkaller.appspotmail.com >>> Fixes: 2d151d39073a ("xfrm: Add possibility to set the default to block if we have no policy") >>> >>> netlink: 172 bytes leftover after parsing attributes in process `syz-executor354'. >>> ================================================================================ >>> UBSAN: shift-out-of-bounds in net/xfrm/xfrm_user.c:2010:49 >>> shift exponent 224 is too large for 32-bit type 'int' >> >> >> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git > > want 2 args (repo, branch), got 3 >
Whoops... :(
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git master
With regards, Pavel SkripkinFrom 0395839028b13f4e380e167c6381e4eea4a9fc42 Mon Sep 17 00:00:00 2001 From: Pavel Skripkin <paskripkin@gmail.com> Date: Wed, 1 Sep 2021 21:55:25 +0300 Subject: [PATCH] net: xfrm: fix shift-out-of-bounds in xfrm_get_default
/* ... */
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> --- net/xfrm/xfrm_user.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index b7b986520dc7..a1dd38525957 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -2007,6 +2007,9 @@ static int xfrm_get_default(struct sk_buff *skb, struct nlmsghdr *nlh, r_up = nlmsg_data(r_nlh); + if (up->dirmask >= XFRM_USERPOLICY_DIRMASK_MAX) + return -EINVAL; + r_up->action = ((net->xfrm.policy_default & (1 << up->dirmask)) >> up->dirmask); r_up->dirmask = up->dirmask; nlmsg_end(r_skb, r_nlh); -- 2.33.0
| |