<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/tipc, branch linux-4.9.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tipc: Fix potential OOB in tipc_link_proto_rcv()</title>
<updated>2022-12-14T10:24:35+00:00</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2022-12-03T09:46:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=62ae69ea7be897d75022999378477b2a94ee90b4'/>
<id>62ae69ea7be897d75022999378477b2a94ee90b4</id>
<content type='text'>
[ Upstream commit 743117a997bbd4840e827295c07e59bcd7f7caa3 ]

Fix the potential risk of OOB if skb_linearize() fails in
tipc_link_proto_rcv().

Fixes: 5cbb28a4bf65 ("tipc: linearize arriving NAME_DISTR and LINK_PROTO buffers")
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20221203094635.29024-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 743117a997bbd4840e827295c07e59bcd7f7caa3 ]

Fix the potential risk of OOB if skb_linearize() fails in
tipc_link_proto_rcv().

Fixes: 5cbb28a4bf65 ("tipc: linearize arriving NAME_DISTR and LINK_PROTO buffers")
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20221203094635.29024-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix the msg-&gt;req tlv len check in tipc_nl_compat_name_table_dump_header</title>
<updated>2022-11-25T16:35:36+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2022-11-04T20:48:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=082707d3df191bf5bb8801d43e4ce3dea39ca173'/>
<id>082707d3df191bf5bb8801d43e4ce3dea39ca173</id>
<content type='text'>
[ Upstream commit 1c075b192fe41030457cd4a5f7dea730412bca40 ]

This is a follow-up for commit 974cb0e3e7c9 ("tipc: fix uninit-value
in tipc_nl_compat_name_table_dump") where it should have type casted
sizeof(..) to int to work when TLV_GET_DATA_LEN() returns a negative
value.

syzbot reported a call trace because of it:

  BUG: KMSAN: uninit-value in ...
   tipc_nl_compat_name_table_dump+0x841/0xea0 net/tipc/netlink_compat.c:934
   __tipc_nl_compat_dumpit+0xab2/0x1320 net/tipc/netlink_compat.c:238
   tipc_nl_compat_dumpit+0x991/0xb50 net/tipc/netlink_compat.c:321
   tipc_nl_compat_recv+0xb6e/0x1640 net/tipc/netlink_compat.c:1324
   genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
   genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
   genl_rcv_msg+0x103f/0x1260 net/netlink/genetlink.c:792
   netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501
   genl_rcv+0x3c/0x50 net/netlink/genetlink.c:803
   netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
   netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
   netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
   sock_sendmsg_nosec net/socket.c:714 [inline]
   sock_sendmsg net/socket.c:734 [inline]

Reported-by: syzbot+e5dbaaa238680ce206ea@syzkaller.appspotmail.com
Fixes: 974cb0e3e7c9 ("tipc: fix uninit-value in tipc_nl_compat_name_table_dump")
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Link: https://lore.kernel.org/r/ccd6a7ea801b15aec092c3b532a883b4c5708695.1667594933.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1c075b192fe41030457cd4a5f7dea730412bca40 ]

This is a follow-up for commit 974cb0e3e7c9 ("tipc: fix uninit-value
in tipc_nl_compat_name_table_dump") where it should have type casted
sizeof(..) to int to work when TLV_GET_DATA_LEN() returns a negative
value.

syzbot reported a call trace because of it:

  BUG: KMSAN: uninit-value in ...
   tipc_nl_compat_name_table_dump+0x841/0xea0 net/tipc/netlink_compat.c:934
   __tipc_nl_compat_dumpit+0xab2/0x1320 net/tipc/netlink_compat.c:238
   tipc_nl_compat_dumpit+0x991/0xb50 net/tipc/netlink_compat.c:321
   tipc_nl_compat_recv+0xb6e/0x1640 net/tipc/netlink_compat.c:1324
   genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
   genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
   genl_rcv_msg+0x103f/0x1260 net/netlink/genetlink.c:792
   netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501
   genl_rcv+0x3c/0x50 net/netlink/genetlink.c:803
   netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
   netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
   netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
   sock_sendmsg_nosec net/socket.c:714 [inline]
   sock_sendmsg net/socket.c:734 [inline]

Reported-by: syzbot+e5dbaaa238680ce206ea@syzkaller.appspotmail.com
Fixes: 974cb0e3e7c9 ("tipc: fix uninit-value in tipc_nl_compat_name_table_dump")
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Link: https://lore.kernel.org/r/ccd6a7ea801b15aec092c3b532a883b4c5708695.1667594933.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix shift wrapping bug in map_get()</title>
<updated>2022-09-15T10:39:46+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2022-08-31T14:47:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f4d04a991d238afb03b692ec5ba9eada3b627a59'/>
<id>f4d04a991d238afb03b692ec5ba9eada3b627a59</id>
<content type='text'>
[ Upstream commit e2b224abd9bf45dcb55750479fc35970725a430b ]

There is a shift wrapping bug in this code so anything thing above
31 will return false.

Fixes: 35c55c9877f8 ("tipc: add neighbor monitoring framework")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e2b224abd9bf45dcb55750479fc35970725a430b ]

There is a shift wrapping bug in this code so anything thing above
31 will return false.

Fixes: 35c55c9877f8 ("tipc: add neighbor monitoring framework")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: tipc: fix possible refcount leak in tipc_sk_create()</title>
<updated>2022-07-21T18:40:32+00:00</updated>
<author>
<name>Hangyu Hua</name>
<email>hbh25y@gmail.com</email>
</author>
<published>2022-06-29T06:34:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=638fa20b618b2bbcf86da71231624cc82121a036'/>
<id>638fa20b618b2bbcf86da71231624cc82121a036</id>
<content type='text'>
[ Upstream commit 00aff3590fc0a73bddd3b743863c14e76fd35c0c ]

Free sk in case tipc_sk_insert() fails.

Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Reviewed-by: Tung Nguyen &lt;tung.q.nguyen@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 00aff3590fc0a73bddd3b743863c14e76fd35c0c ]

Free sk in case tipc_sk_insert() fails.

Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Reviewed-by: Tung Nguyen &lt;tung.q.nguyen@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: rate limit warning for received illegal binding update</title>
<updated>2022-02-16T11:43:54+00:00</updated>
<author>
<name>Jon Maloy</name>
<email>jmaloy@redhat.com</email>
</author>
<published>2022-02-09T03:22:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9839da923ff9eaaae7cb3fc9d59bf2141cc3e15d'/>
<id>9839da923ff9eaaae7cb3fc9d59bf2141cc3e15d</id>
<content type='text'>
[ Upstream commit c7223d687758462826a20e9735305d55bb874c70 ]

It would be easy to craft a message containing an illegal binding table
update operation. This is handled correctly by the code, but the
corresponding warning printout is not rate limited as is should be.
We fix this now.

Fixes: b97bf3fd8f6a ("[TIPC] Initial merge")
Signed-off-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c7223d687758462826a20e9735305d55bb874c70 ]

It would be easy to craft a message containing an illegal binding table
update operation. This is handled correctly by the code, but the
corresponding warning printout is not rate limited as is should be.
We fix this now.

Fixes: b97bf3fd8f6a ("[TIPC] Initial merge")
Signed-off-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: improve size validations for received domain records</title>
<updated>2022-02-11T07:41:17+00:00</updated>
<author>
<name>Jon Maloy</name>
<email>jmaloy@redhat.com</email>
</author>
<published>2022-02-05T19:11:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=175db196e45d6f0e6047eccd09c8ba55465eb131'/>
<id>175db196e45d6f0e6047eccd09c8ba55465eb131</id>
<content type='text'>
commit 9aa422ad326634b76309e8ff342c246800621216 upstream.

The function tipc_mon_rcv() allows a node to receive and process
domain_record structs from peer nodes to track their views of the
network topology.

This patch verifies that the number of members in a received domain
record does not exceed the limit defined by MAX_MON_DOMAIN, something
that may otherwise lead to a stack overflow.

tipc_mon_rcv() is called from the function tipc_link_proto_rcv(), where
we are reading a 32 bit message data length field into a uint16.  To
avert any risk of bit overflow, we add an extra sanity check for this in
that function.  We cannot see that happen with the current code, but
future designers being unaware of this risk, may introduce it by
allowing delivery of very large (&gt; 64k) sk buffers from the bearer
layer.  This potential problem was identified by Eric Dumazet.

This fixes CVE-2022-0435

Reported-by: Samuel Page &lt;samuel.page@appgate.com&gt;
Reported-by: Eric Dumazet &lt;edumazet@google.com&gt;
Fixes: 35c55c9877f8 ("tipc: add neighbor monitoring framework")
Signed-off-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Reviewed-by: Samuel Page &lt;samuel.page@appgate.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9aa422ad326634b76309e8ff342c246800621216 upstream.

The function tipc_mon_rcv() allows a node to receive and process
domain_record structs from peer nodes to track their views of the
network topology.

This patch verifies that the number of members in a received domain
record does not exceed the limit defined by MAX_MON_DOMAIN, something
that may otherwise lead to a stack overflow.

tipc_mon_rcv() is called from the function tipc_link_proto_rcv(), where
we are reading a 32 bit message data length field into a uint16.  To
avert any risk of bit overflow, we add an extra sanity check for this in
that function.  We cannot see that happen with the current code, but
future designers being unaware of this risk, may introduce it by
allowing delivery of very large (&gt; 64k) sk buffers from the bearer
layer.  This potential problem was identified by Eric Dumazet.

This fixes CVE-2022-0435

Reported-by: Samuel Page &lt;samuel.page@appgate.com&gt;
Reported-by: Eric Dumazet &lt;edumazet@google.com&gt;
Fixes: 35c55c9877f8 ("tipc: add neighbor monitoring framework")
Signed-off-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Reviewed-by: Samuel Page &lt;samuel.page@appgate.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: increase timeout in tipc_sk_enqueue()</title>
<updated>2021-09-22T09:43:09+00:00</updated>
<author>
<name>Hoang Le</name>
<email>hoang.h.le@dektech.com.au</email>
</author>
<published>2021-09-13T09:28:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=de9b2e5256951d542bf8721fdb216ce3d6c463ba'/>
<id>de9b2e5256951d542bf8721fdb216ce3d6c463ba</id>
<content type='text'>
commit f4bb62e64c88c93060c051195d3bbba804e56945 upstream.

In tipc_sk_enqueue() we use hardcoded 2 jiffies to extract
socket buffer from generic queue to particular socket.
The 2 jiffies is too short in case there are other high priority
tasks get CPU cycles for multiple jiffies update. As result, no
buffer could be enqueued to particular socket.

To solve this, we switch to use constant timeout 20msecs.
Then, the function will be expired between 2 jiffies (CONFIG_100HZ)
and 20 jiffies (CONFIG_1000HZ).

Fixes: c637c1035534 ("tipc: resolve race problem at unicast message reception")
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f4bb62e64c88c93060c051195d3bbba804e56945 upstream.

In tipc_sk_enqueue() we use hardcoded 2 jiffies to extract
socket buffer from generic queue to particular socket.
The 2 jiffies is too short in case there are other high priority
tasks get CPU cycles for multiple jiffies update. As result, no
buffer could be enqueued to particular socket.

To solve this, we switch to use constant timeout 20msecs.
Then, the function will be expired between 2 jiffies (CONFIG_100HZ)
and 20 jiffies (CONFIG_1000HZ).

Fixes: c637c1035534 ("tipc: resolve race problem at unicast message reception")
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix sleeping in tipc accept routine</title>
<updated>2021-08-04T09:58:03+00:00</updated>
<author>
<name>Hoang Le</name>
<email>hoang.h.le@dektech.com.au</email>
</author>
<published>2021-07-23T02:25:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a1d2c2ed0650ad924d9007dc2931020c47c41394'/>
<id>a1d2c2ed0650ad924d9007dc2931020c47c41394</id>
<content type='text'>
[ Upstream commit d237a7f11719ff9320721be5818352e48071aab6 ]

The release_sock() is blocking function, it would change the state
after sleeping. In order to evaluate the stated condition outside
the socket lock context, switch to use wait_woken() instead.

Fixes: 6398e23cdb1d8 ("tipc: standardize accept routine")
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d237a7f11719ff9320721be5818352e48071aab6 ]

The release_sock() is blocking function, it would change the state
after sleeping. In order to evaluate the stated condition outside
the socket lock context, switch to use wait_woken() instead.

Fixes: 6398e23cdb1d8 ("tipc: standardize accept routine")
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: Fix backport of b77413446408fdd256599daf00d5be72b5f3e7c6</title>
<updated>2021-08-04T09:58:01+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2021-07-27T22:56:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=088f160d6f6dc06cf858e864ba8e81548387af1e'/>
<id>088f160d6f6dc06cf858e864ba8e81548387af1e</id>
<content type='text'>
Clang warns:

net/tipc/link.c:896:23: warning: variable 'hdr' is uninitialized when
used here [-Wuninitialized]
        imp = msg_importance(hdr);
                             ^~~
net/tipc/link.c:890:22: note: initialize the variable 'hdr' to silence
this warning
        struct tipc_msg *hdr;
                            ^
                             = NULL
1 warning generated.

The backport of commit b77413446408 ("tipc: fix NULL deref in
tipc_link_xmit()") to 4.9 as commit 310014f572a5 ("tipc: fix NULL deref
in tipc_link_xmit()") added the hdr initialization above the

    if (unlikely(msg_size(hdr) &gt; mtu)) {

like in the upstream commit; however, in 4.9, that check is below imp's
first use because commit 365ad353c256 ("tipc: reduce risk of user
starvation during link congestion") is not present. This results in hdr
being used uninitialized.

Fix this by moving hdr's initialization before imp and after the if
check like the original backport did.

Cc: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Cc: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Cc: Ying Xue &lt;ying.xue@windriver.com&gt;
Fixes: 310014f572a5 ("tipc: fix NULL deref in tipc_link_xmit()")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Clang warns:

net/tipc/link.c:896:23: warning: variable 'hdr' is uninitialized when
used here [-Wuninitialized]
        imp = msg_importance(hdr);
                             ^~~
net/tipc/link.c:890:22: note: initialize the variable 'hdr' to silence
this warning
        struct tipc_msg *hdr;
                            ^
                             = NULL
1 warning generated.

The backport of commit b77413446408 ("tipc: fix NULL deref in
tipc_link_xmit()") to 4.9 as commit 310014f572a5 ("tipc: fix NULL deref
in tipc_link_xmit()") added the hdr initialization above the

    if (unlikely(msg_size(hdr) &gt; mtu)) {

like in the upstream commit; however, in 4.9, that check is below imp's
first use because commit 365ad353c256 ("tipc: reduce risk of user
starvation during link congestion") is not present. This results in hdr
being used uninitialized.

Fix this by moving hdr's initialization before imp and after the if
check like the original backport did.

Cc: Hoang Le &lt;hoang.h.le@dektech.com.au&gt;
Cc: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Cc: Ying Xue &lt;ying.xue@windriver.com&gt;
Fixes: 310014f572a5 ("tipc: fix NULL deref in tipc_link_xmit()")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: skb_linearize the head skb when reassembling msgs</title>
<updated>2021-06-03T06:23:30+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2021-05-07T19:57:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5489f30bb78ff0dafb4229a69632afc2ba20765c'/>
<id>5489f30bb78ff0dafb4229a69632afc2ba20765c</id>
<content type='text'>
commit b7df21cf1b79ab7026f545e7bf837bd5750ac026 upstream.

It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.

However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.

The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by this when doing testing over macvlan devices:

  [] kernel BUG at net/core/skbuff.c:1970!
  [] Call Trace:
  []  skb_clone+0x4d/0xb0
  []  macvlan_broadcast+0xd8/0x160 [macvlan]
  []  macvlan_process_broadcast+0x148/0x150 [macvlan]
  []  process_one_work+0x1a7/0x360
  []  worker_thread+0x30/0x390

  [] kernel BUG at mm/usercopy.c:102!
  [] Call Trace:
  []  __check_heap_object+0xd3/0x100
  []  __check_object_size+0xff/0x16b
  []  simple_copy_to_iter+0x1c/0x30
  []  __skb_datagram_iter+0x7d/0x310
  []  __skb_datagram_iter+0x2a5/0x310
  []  skb_copy_datagram_iter+0x3b/0x90
  []  tipc_recvmsg+0x14a/0x3a0 [tipc]
  []  ____sys_recvmsg+0x91/0x150
  []  ___sys_recvmsg+0x7b/0xc0

  [] kernel BUG at mm/slub.c:305!
  [] Call Trace:
  []  &lt;IRQ&gt;
  []  kmem_cache_free+0x3ff/0x400
  []  __netif_receive_skb_core+0x12c/0xc40
  []  ? kmem_cache_alloc+0x12e/0x270
  []  netif_receive_skb_internal+0x3d/0xb0
  []  ? get_rx_page_info+0x8e/0xa0 [be2net]
  []  be_poll+0x6ef/0xd00 [be2net]
  []  ? irq_exit+0x4f/0x100
  []  net_rx_action+0x149/0x3b0

  ...

This patch is to fix it by linearizing the head skb if it has frag_list
set in tipc_buf_append(). Note that we choose to do this before calling
skb_unshare(), as __skb_linearize() will avoid skb_copy(). Also, we can
not just drop the frag_list either as the early time.

Fixes: 45c8b7b175ce ("tipc: allow non-linear first fragment buffer")
Reported-by: Li Shuang &lt;shuali@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b7df21cf1b79ab7026f545e7bf837bd5750ac026 upstream.

It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.

However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.

The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by this when doing testing over macvlan devices:

  [] kernel BUG at net/core/skbuff.c:1970!
  [] Call Trace:
  []  skb_clone+0x4d/0xb0
  []  macvlan_broadcast+0xd8/0x160 [macvlan]
  []  macvlan_process_broadcast+0x148/0x150 [macvlan]
  []  process_one_work+0x1a7/0x360
  []  worker_thread+0x30/0x390

  [] kernel BUG at mm/usercopy.c:102!
  [] Call Trace:
  []  __check_heap_object+0xd3/0x100
  []  __check_object_size+0xff/0x16b
  []  simple_copy_to_iter+0x1c/0x30
  []  __skb_datagram_iter+0x7d/0x310
  []  __skb_datagram_iter+0x2a5/0x310
  []  skb_copy_datagram_iter+0x3b/0x90
  []  tipc_recvmsg+0x14a/0x3a0 [tipc]
  []  ____sys_recvmsg+0x91/0x150
  []  ___sys_recvmsg+0x7b/0xc0

  [] kernel BUG at mm/slub.c:305!
  [] Call Trace:
  []  &lt;IRQ&gt;
  []  kmem_cache_free+0x3ff/0x400
  []  __netif_receive_skb_core+0x12c/0xc40
  []  ? kmem_cache_alloc+0x12e/0x270
  []  netif_receive_skb_internal+0x3d/0xb0
  []  ? get_rx_page_info+0x8e/0xa0 [be2net]
  []  be_poll+0x6ef/0xd00 [be2net]
  []  ? irq_exit+0x4f/0x100
  []  net_rx_action+0x149/0x3b0

  ...

This patch is to fix it by linearizing the head skb if it has frag_list
set in tipc_buf_append(). Note that we choose to do this before calling
skb_unshare(), as __skb_linearize() will avoid skb_copy(). Also, we can
not just drop the frag_list either as the early time.

Fixes: 45c8b7b175ce ("tipc: allow non-linear first fragment buffer")
Reported-by: Li Shuang &lt;shuali@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
