All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat
@ 2019-03-31 14:50 Xin Long
  2019-03-31 14:50 ` [PATCH net 1/3] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable Xin Long
  2019-03-31 22:27 ` [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Jon Maloy
  0 siblings, 2 replies; 6+ messages in thread
From: Xin Long @ 2019-03-31 14:50 UTC (permalink / raw)
  To: network dev; +Cc: davem, Jon Maloy, Ying Xue, tipc-discussion, syzkaller

These issues were all reported by syzbot, and exist since very beginning.
See the details on each patch.

Xin Long (3):
  tipc: check bearer name with right length in
    tipc_nl_compat_bearer_enable
  tipc: check link name with right length in tipc_nl_compat_link_set
  tipc: handle the err returned from cmd header function

 net/tipc/netlink_compat.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

-- 
2.1.0


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH net 1/3] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable
  2019-03-31 14:50 [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Xin Long
@ 2019-03-31 14:50 ` Xin Long
  2019-03-31 14:50   ` [PATCH net 2/3] tipc: check link name with right length in tipc_nl_compat_link_set Xin Long
  2019-03-31 22:27 ` [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Jon Maloy
  1 sibling, 1 reply; 6+ messages in thread
From: Xin Long @ 2019-03-31 14:50 UTC (permalink / raw)
  To: network dev; +Cc: davem, Jon Maloy, Ying Xue, tipc-discussion, syzkaller

Syzbot reported the following crash:

BUG: KMSAN: uninit-value in memchr+0xce/0x110 lib/string.c:961
  memchr+0xce/0x110 lib/string.c:961
  string_is_valid net/tipc/netlink_compat.c:176 [inline]
  tipc_nl_compat_bearer_enable+0x2c4/0x910 net/tipc/netlink_compat.c:401
  __tipc_nl_compat_doit net/tipc/netlink_compat.c:321 [inline]
  tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:354
  tipc_nl_compat_handle net/tipc/netlink_compat.c:1162 [inline]
  tipc_nl_compat_recv+0x1ae7/0x2750 net/tipc/netlink_compat.c:1265
  genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
  genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
  netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
  genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:622 [inline]
  sock_sendmsg net/socket.c:632 [inline]

Uninit was created at:
  __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
  alloc_skb include/linux/skbuff.h:1012 [inline]
  netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
  netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
  sock_sendmsg_nosec net/socket.c:622 [inline]
  sock_sendmsg net/socket.c:632 [inline]

It was triggered when the bearer name size < TIPC_MAX_BEARER_NAME,
it would check with a wrong len/TLV_GET_DATA_LEN(msg->req), which
also includes priority and disc_domain length.

This patch is to fix it by checking it with a right length:
'TLV_GET_DATA_LEN(msg->req) - offsetof(struct tipc_bearer_config, name)'.

Reported-by: syzbot+8b707430713eb46e1e45@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/tipc/netlink_compat.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 4ad3586..5f8e53c 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -397,7 +397,12 @@ static int tipc_nl_compat_bearer_enable(struct tipc_nl_compat_cmd_doit *cmd,
 	if (!bearer)
 		return -EMSGSIZE;
 
-	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME);
+	len = TLV_GET_DATA_LEN(msg->req);
+	len -= offsetof(struct tipc_bearer_config, name);
+	if (len <= 0)
+		return -EINVAL;
+
+	len = min_t(int, len, TIPC_MAX_BEARER_NAME);
 	if (!string_is_valid(b->name, len))
 		return -EINVAL;
 
-- 
2.1.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH net 2/3] tipc: check link name with right length in tipc_nl_compat_link_set
  2019-03-31 14:50 ` [PATCH net 1/3] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable Xin Long
@ 2019-03-31 14:50   ` Xin Long
  2019-03-31 14:50     ` [PATCH net 3/3] tipc: handle the err returned from cmd header function Xin Long
  0 siblings, 1 reply; 6+ messages in thread
From: Xin Long @ 2019-03-31 14:50 UTC (permalink / raw)
  To: network dev; +Cc: davem, Jon Maloy, Ying Xue, tipc-discussion, syzkaller

A similar issue as fixed by Patch "tipc: check bearer name with right
length in tipc_nl_compat_bearer_enable" was also found by syzbot in
tipc_nl_compat_link_set().

The length to check with should be 'TLV_GET_DATA_LEN(msg->req) -
offsetof(struct tipc_link_config, name)'.

Reported-by: syzbot+de00a87b8644a582ae79@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/tipc/netlink_compat.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 5f8e53c..0bfd03d6 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -771,7 +771,12 @@ static int tipc_nl_compat_link_set(struct tipc_nl_compat_cmd_doit *cmd,
 
 	lc = (struct tipc_link_config *)TLV_DATA(msg->req);
 
-	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME);
+	len = TLV_GET_DATA_LEN(msg->req);
+	len -= offsetof(struct tipc_link_config, name);
+	if (len <= 0)
+		return -EINVAL;
+
+	len = min_t(int, len, TIPC_MAX_LINK_NAME);
 	if (!string_is_valid(lc->name, len))
 		return -EINVAL;
 
-- 
2.1.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH net 3/3] tipc: handle the err returned from cmd header function
  2019-03-31 14:50   ` [PATCH net 2/3] tipc: check link name with right length in tipc_nl_compat_link_set Xin Long
@ 2019-03-31 14:50     ` Xin Long
  0 siblings, 0 replies; 6+ messages in thread
From: Xin Long @ 2019-03-31 14:50 UTC (permalink / raw)
  To: network dev; +Cc: davem, Jon Maloy, Ying Xue, tipc-discussion, syzkaller

Syzbot found a crash:

  BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
  Call Trace:
    tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
    __tipc_nl_compat_dumpit+0x59e/0xda0 net/tipc/netlink_compat.c:215
    tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:280
    tipc_nl_compat_handle net/tipc/netlink_compat.c:1226 [inline]
    tipc_nl_compat_recv+0x1b5f/0x2750 net/tipc/netlink_compat.c:1265
    genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
    genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
    netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
    genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
    netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
    netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
    netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
    sock_sendmsg_nosec net/socket.c:622 [inline]
    sock_sendmsg net/socket.c:632 [inline]

  Uninit was created at:
    __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
    alloc_skb include/linux/skbuff.h:1012 [inline]
    netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
    netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
    sock_sendmsg_nosec net/socket.c:622 [inline]
    sock_sendmsg net/socket.c:632 [inline]

It was supposed to be fixed on commit 974cb0e3e7c9 ("tipc: fix uninit-value
in tipc_nl_compat_name_table_dump") by checking TLV_GET_DATA_LEN(msg->req)
in cmd->header()/tipc_nl_compat_name_table_dump_header(), which is called
ahead of tipc_nl_compat_name_table_dump().

However, tipc_nl_compat_dumpit() doesn't handle the error returned from cmd
header function. It means even when the check added in that fix fails, it
won't stop calling tipc_nl_compat_name_table_dump(), and the issue will be
triggered again.

So this patch is to add the process for the err returned from cmd header
function in tipc_nl_compat_dumpit().

Reported-by: syzbot+3ce8520484b0d4e260a5@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/tipc/netlink_compat.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 0bfd03d6..340a6e7 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -267,8 +267,14 @@ static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd,
 	if (msg->rep_type)
 		tipc_tlv_init(msg->rep, msg->rep_type);
 
-	if (cmd->header)
-		(*cmd->header)(msg);
+	if (cmd->header) {
+		err = (*cmd->header)(msg);
+		if (err) {
+			kfree_skb(msg->rep);
+			msg->rep = NULL;
+			return err;
+		}
+	}
 
 	arg = nlmsg_new(0, GFP_KERNEL);
 	if (!arg) {
-- 
2.1.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* RE: [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat
  2019-03-31 14:50 [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Xin Long
  2019-03-31 14:50 ` [PATCH net 1/3] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable Xin Long
@ 2019-03-31 22:27 ` Jon Maloy
  2019-03-31 23:46   ` David Miller
  1 sibling, 1 reply; 6+ messages in thread
From: Jon Maloy @ 2019-03-31 22:27 UTC (permalink / raw)
  To: Xin Long, network dev; +Cc: davem, Ying Xue, tipc-discussion, syzkaller

All three acked by me.

///jon


> -----Original Message-----
> From: Xin Long <lucien.xin@gmail.com>
> Sent: 31-Mar-19 10:50
> To: network dev <netdev@vger.kernel.org>
> Cc: davem@davemloft.net; Jon Maloy <jon.maloy@ericsson.com>; Ying Xue
> <ying.xue@windriver.com>; tipc-discussion@lists.sourceforge.net;
> syzkaller@googlegroups.com
> Subject: [PATCH net 0/3] tipc: a batch of uninit-value fixes for
> netlink_compat
> 
> These issues were all reported by syzbot, and exist since very beginning.
> See the details on each patch.
> 
> Xin Long (3):
>   tipc: check bearer name with right length in
>     tipc_nl_compat_bearer_enable
>   tipc: check link name with right length in tipc_nl_compat_link_set
>   tipc: handle the err returned from cmd header function
> 
>  net/tipc/netlink_compat.c | 24 ++++++++++++++++++++----
>  1 file changed, 20 insertions(+), 4 deletions(-)
> 
> --
> 2.1.0


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat
  2019-03-31 22:27 ` [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Jon Maloy
@ 2019-03-31 23:46   ` David Miller
  0 siblings, 0 replies; 6+ messages in thread
From: David Miller @ 2019-03-31 23:46 UTC (permalink / raw)
  To: jon.maloy; +Cc: lucien.xin, netdev, ying.xue, tipc-discussion, syzkaller

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Sun, 31 Mar 2019 22:27:19 +0000

> All three acked by me.

Series applied.

Jon, please provide a formal, full:

Acked-by: David S. Miller <davem@davemloft.net>

next time.

Thank you.

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2019-03-31 23:46 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-03-31 14:50 [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Xin Long
2019-03-31 14:50 ` [PATCH net 1/3] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable Xin Long
2019-03-31 14:50   ` [PATCH net 2/3] tipc: check link name with right length in tipc_nl_compat_link_set Xin Long
2019-03-31 14:50     ` [PATCH net 3/3] tipc: handle the err returned from cmd header function Xin Long
2019-03-31 22:27 ` [PATCH net 0/3] tipc: a batch of uninit-value fixes for netlink_compat Jon Maloy
2019-03-31 23:46   ` David Miller

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.