<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net, branch v4.19.255</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>netfilter: nf_queue: do not allow packet truncation below transport header offset</title>
<updated>2022-08-11T10:48:40+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2022-07-26T10:42:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f295d365b30626f82423a923695274024016380e'/>
<id>f295d365b30626f82423a923695274024016380e</id>
<content type='text'>
[ Upstream commit 99a63d36cb3ed5ca3aa6fcb64cffbeaf3b0fb164 ]

Domingo Dirutigliano and Nicola Guerrera report kernel panic when
sending nf_queue verdict with 1-byte nfta_payload attribute.

The IP/IPv6 stack pulls the IP(v6) header from the packet after the
input hook.

If user truncates the packet below the header size, this skb_pull() will
result in a malformed skb (skb-&gt;len &lt; 0).

Fixes: 7af4cc3fa158 ("[NETFILTER]: Add "nfnetlink_queue" netfilter queue handler over nfnetlink")
Reported-by: Domingo Dirutigliano &lt;pwnzer0tt1@proton.me&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Reviewed-by: Pablo Neira Ayuso &lt;pablo@netfilter.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 99a63d36cb3ed5ca3aa6fcb64cffbeaf3b0fb164 ]

Domingo Dirutigliano and Nicola Guerrera report kernel panic when
sending nf_queue verdict with 1-byte nfta_payload attribute.

The IP/IPv6 stack pulls the IP(v6) header from the packet after the
input hook.

If user truncates the packet below the header size, this skb_pull() will
result in a malformed skb (skb-&gt;len &lt; 0).

Fixes: 7af4cc3fa158 ("[NETFILTER]: Add "nfnetlink_queue" netfilter queue handler over nfnetlink")
Reported-by: Domingo Dirutigliano &lt;pwnzer0tt1@proton.me&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Reviewed-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sctp: fix sleep in atomic context bug in timer handlers</title>
<updated>2022-08-11T10:48:40+00:00</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-07-23T01:58:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=5bf4a38defa93e6f159dcfdcc3ad2d0f9aaf7584'/>
<id>5bf4a38defa93e6f159dcfdcc3ad2d0f9aaf7584</id>
<content type='text'>
[ Upstream commit b89fc26f741d9f9efb51cba3e9b241cf1380ec5a ]

There are sleep in atomic context bugs in timer handlers of sctp
such as sctp_generate_t3_rtx_event(), sctp_generate_probe_event(),
sctp_generate_t1_init_event(), sctp_generate_timeout_event(),
sctp_generate_t3_rtx_event() and so on.

The root cause is sctp_sched_prio_init_sid() with GFP_KERNEL parameter
that may sleep could be called by different timer handlers which is in
interrupt context.

One of the call paths that could trigger bug is shown below:

      (interrupt context)
sctp_generate_probe_event
  sctp_do_sm
    sctp_side_effects
      sctp_cmd_interpreter
        sctp_outq_teardown
          sctp_outq_init
            sctp_sched_set_sched
              n-&gt;init_sid(..,GFP_KERNEL)
                sctp_sched_prio_init_sid //may sleep

This patch changes gfp_t parameter of init_sid in sctp_sched_set_sched()
from GFP_KERNEL to GFP_ATOMIC in order to prevent sleep in atomic
context bugs.

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Link: https://lore.kernel.org/r/20220723015809.11553-1-duoming@zju.edu.cn
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 b89fc26f741d9f9efb51cba3e9b241cf1380ec5a ]

There are sleep in atomic context bugs in timer handlers of sctp
such as sctp_generate_t3_rtx_event(), sctp_generate_probe_event(),
sctp_generate_t1_init_event(), sctp_generate_timeout_event(),
sctp_generate_t3_rtx_event() and so on.

The root cause is sctp_sched_prio_init_sid() with GFP_KERNEL parameter
that may sleep could be called by different timer handlers which is in
interrupt context.

One of the call paths that could trigger bug is shown below:

      (interrupt context)
sctp_generate_probe_event
  sctp_do_sm
    sctp_side_effects
      sctp_cmd_interpreter
        sctp_outq_teardown
          sctp_outq_init
            sctp_sched_set_sched
              n-&gt;init_sid(..,GFP_KERNEL)
                sctp_sched_prio_init_sid //may sleep

This patch changes gfp_t parameter of init_sid in sctp_sched_set_sched()
from GFP_KERNEL to GFP_ATOMIC in order to prevent sleep in atomic
context bugs.

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Link: https://lore.kernel.org/r/20220723015809.11553-1-duoming@zju.edu.cn
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>tcp: Fix a data-race around sysctl_tcp_comp_sack_nr.</title>
<updated>2022-08-11T10:48:40+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-22T18:22:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=37ef2ea54885ffebc45fae73f04352bab0ffb367'/>
<id>37ef2ea54885ffebc45fae73f04352bab0ffb367</id>
<content type='text'>
[ Upstream commit 79f55473bfc8ac51bd6572929a679eeb4da22251 ]

While reading sysctl_tcp_comp_sack_nr, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 9c21d2fc41c0 ("tcp: add tcp_comp_sack_nr sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 79f55473bfc8ac51bd6572929a679eeb4da22251 ]

While reading sysctl_tcp_comp_sack_nr, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 9c21d2fc41c0 ("tcp: add tcp_comp_sack_nr sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>tcp: Fix a data-race around sysctl_tcp_comp_sack_delay_ns.</title>
<updated>2022-08-11T10:48:40+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-22T18:22:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=32917d384b89836e593aa8ef795508257fd7d102'/>
<id>32917d384b89836e593aa8ef795508257fd7d102</id>
<content type='text'>
[ Upstream commit 4866b2b0f7672b6d760c4b8ece6fb56f965dcc8a ]

While reading sysctl_tcp_comp_sack_delay_ns, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 6d82aa242092 ("tcp: add tcp_comp_sack_delay_ns sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 4866b2b0f7672b6d760c4b8ece6fb56f965dcc8a ]

While reading sysctl_tcp_comp_sack_delay_ns, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 6d82aa242092 ("tcp: add tcp_comp_sack_delay_ns sysctl")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>tcp: Fix a data-race around sysctl_tcp_invalid_ratelimit.</title>
<updated>2022-08-11T10:48:40+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-20T16:50:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=69eab4c78d7a366d75de3d07e0a4a9e7c81291c1'/>
<id>69eab4c78d7a366d75de3d07e0a4a9e7c81291c1</id>
<content type='text'>
[ Upstream commit 2afdbe7b8de84c28e219073a6661080e1b3ded48 ]

While reading sysctl_tcp_invalid_ratelimit, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 032ee4236954 ("tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 2afdbe7b8de84c28e219073a6661080e1b3ded48 ]

While reading sysctl_tcp_invalid_ratelimit, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 032ee4236954 ("tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>tcp: Fix a data-race around sysctl_tcp_autocorking.</title>
<updated>2022-08-11T10:48:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-20T16:50:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=5e3d32bb5884cd0c992542f7a887e26d4118b415'/>
<id>5e3d32bb5884cd0c992542f7a887e26d4118b415</id>
<content type='text'>
[ Upstream commit 85225e6f0a76e6745bc841c9f25169c509b573d8 ]

While reading sysctl_tcp_autocorking, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f54b311142a9 ("tcp: auto corking")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 85225e6f0a76e6745bc841c9f25169c509b573d8 ]

While reading sysctl_tcp_autocorking, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f54b311142a9 ("tcp: auto corking")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>tcp: Fix a data-race around sysctl_tcp_min_rtt_wlen.</title>
<updated>2022-08-11T10:48:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-20T16:50:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=3a73df9db9297ada3e58776810c8e52332f3f1a0'/>
<id>3a73df9db9297ada3e58776810c8e52332f3f1a0</id>
<content type='text'>
[ Upstream commit 1330ffacd05fc9ac4159d19286ce119e22450ed2 ]

While reading sysctl_tcp_min_rtt_wlen, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f672258391b4 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 1330ffacd05fc9ac4159d19286ce119e22450ed2 ]

While reading sysctl_tcp_min_rtt_wlen, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f672258391b4 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>tcp: Fix a data-race around sysctl_tcp_min_tso_segs.</title>
<updated>2022-08-11T10:48:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-20T16:50:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=15085721749ad8d3063a54252d974a24a9751c15'/>
<id>15085721749ad8d3063a54252d974a24a9751c15</id>
<content type='text'>
[ Upstream commit e0bb4ab9dfddd872622239f49fb2bd403b70853b ]

While reading sysctl_tcp_min_tso_segs, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 95bd09eb2750 ("tcp: TSO packets automatic sizing")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 e0bb4ab9dfddd872622239f49fb2bd403b70853b ]

While reading sysctl_tcp_min_tso_segs, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 95bd09eb2750 ("tcp: TSO packets automatic sizing")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>igmp: Fix data-races around sysctl_igmp_qrv.</title>
<updated>2022-08-11T10:48:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-15T17:17:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9eeb3a7702998bdccbfcc37997b5dd9215b9a7f7'/>
<id>9eeb3a7702998bdccbfcc37997b5dd9215b9a7f7</id>
<content type='text'>
[ Upstream commit 8ebcc62c738f68688ee7c6fec2efe5bc6d3d7e60 ]

While reading sysctl_igmp_qrv, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

This test can be packed into a helper, so such changes will be in the
follow-up series after net is merged into net-next.

  qrv ?: READ_ONCE(net-&gt;ipv4.sysctl_igmp_qrv);

Fixes: a9fe8e29945d ("ipv4: implement igmp_qrv sysctl to tune igmp robustness variable")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 8ebcc62c738f68688ee7c6fec2efe5bc6d3d7e60 ]

While reading sysctl_igmp_qrv, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

This test can be packed into a helper, so such changes will be in the
follow-up series after net is merged into net-next.

  qrv ?: READ_ONCE(net-&gt;ipv4.sysctl_igmp_qrv);

Fixes: a9fe8e29945d ("ipv4: implement igmp_qrv sysctl to tune igmp robustness variable")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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: ping6: Fix memleak in ipv6_renew_options().</title>
<updated>2022-08-11T10:48:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-28T01:22:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7cbb889748931d6552c8a8f0fe7f8cbb2edfc1c1'/>
<id>7cbb889748931d6552c8a8f0fe7f8cbb2edfc1c1</id>
<content type='text'>
commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.

When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk-&gt;sk_prot-&gt;destroy().  As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.

    struct ipv6_sr_hdr *hdr;
    char data[24] = {0};
    int fd;

    hdr = (struct ipv6_sr_hdr *)data;
    hdr-&gt;hdrlen = 2;
    hdr-&gt;type = IPV6_SRCRT_TYPE_4;

    fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
    setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
    close(fd);

To fix memory leaks, let's add a destroy function.

Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range.  The default value is [1, 0] so that no
GID meets the condition (1 &lt;= GID &lt;= 0).  Thus, the local DoS does
not succeed until we change the default value.  However, at least
Ubuntu/Fedora/RHEL loosen it.

    $ cat /usr/lib/sysctl.d/50-default.conf
    ...
    -net.ipv4.ping_group_range = 0 2147483647

Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.

  setsockopt
      IPV6_ADDRFORM (inet6_sk(sk)-&gt;pktoptions)
      IPV6_RECVPATHMTU (inet6_sk(sk)-&gt;rxpmtu)
      IPV6_HOPOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDRDSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDR (inet6_sk(sk)-&gt;opt)
      IPV6_DSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_2292PKTOPTIONS (inet6_sk(sk)-&gt;opt)

  getsockopt
      IPV6_FLOWLABEL_MGR (inet6_sk(sk)-&gt;ipv6_fl_list)

For the record, I left a different splat with syzbot's one.

  unreferenced object 0xffff888006270c60 (size 96):
    comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
    hex dump (first 32 bytes):
      01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00  ....D...........
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [&lt;00000000f6bc7ea9&gt;] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
      [&lt;000000006d699550&gt;] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
      [&lt;00000000c3c3b1f5&gt;] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
      [&lt;000000007096a025&gt;] __sys_setsockopt (net/socket.c:2254)
      [&lt;000000003a8ff47b&gt;] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
      [&lt;000000007c409dcb&gt;] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
      [&lt;00000000e939c4a9&gt;] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176

Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.")
Reported-by: syzbot+a8430774139ec3ab7176@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta &lt;ayudutta@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220728012220.46918-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.

When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk-&gt;sk_prot-&gt;destroy().  As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.

    struct ipv6_sr_hdr *hdr;
    char data[24] = {0};
    int fd;

    hdr = (struct ipv6_sr_hdr *)data;
    hdr-&gt;hdrlen = 2;
    hdr-&gt;type = IPV6_SRCRT_TYPE_4;

    fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
    setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
    close(fd);

To fix memory leaks, let's add a destroy function.

Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range.  The default value is [1, 0] so that no
GID meets the condition (1 &lt;= GID &lt;= 0).  Thus, the local DoS does
not succeed until we change the default value.  However, at least
Ubuntu/Fedora/RHEL loosen it.

    $ cat /usr/lib/sysctl.d/50-default.conf
    ...
    -net.ipv4.ping_group_range = 0 2147483647

Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.

  setsockopt
      IPV6_ADDRFORM (inet6_sk(sk)-&gt;pktoptions)
      IPV6_RECVPATHMTU (inet6_sk(sk)-&gt;rxpmtu)
      IPV6_HOPOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDRDSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDR (inet6_sk(sk)-&gt;opt)
      IPV6_DSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_2292PKTOPTIONS (inet6_sk(sk)-&gt;opt)

  getsockopt
      IPV6_FLOWLABEL_MGR (inet6_sk(sk)-&gt;ipv6_fl_list)

For the record, I left a different splat with syzbot's one.

  unreferenced object 0xffff888006270c60 (size 96):
    comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
    hex dump (first 32 bytes):
      01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00  ....D...........
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [&lt;00000000f6bc7ea9&gt;] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
      [&lt;000000006d699550&gt;] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
      [&lt;00000000c3c3b1f5&gt;] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
      [&lt;000000007096a025&gt;] __sys_setsockopt (net/socket.c:2254)
      [&lt;000000003a8ff47b&gt;] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
      [&lt;000000007c409dcb&gt;] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
      [&lt;00000000e939c4a9&gt;] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176

Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.")
Reported-by: syzbot+a8430774139ec3ab7176@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta &lt;ayudutta@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220728012220.46918-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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