<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv6, branch v6.6.9</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>net/ipv6: Revert remove expired routes with a separated list of routes</title>
<updated>2024-01-01T12:42:33+00:00</updated>
<author>
<name>David Ahern</name>
<email>dsahern@kernel.org</email>
</author>
<published>2023-12-19T03:02:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b577b9aa1340ee7f36441b0740691550abaad5f2'/>
<id>b577b9aa1340ee7f36441b0740691550abaad5f2</id>
<content type='text'>
[ Upstream commit dade3f6a1e4e35a5ae916d5e78b3229ec34c78ec ]

This reverts commit 3dec89b14d37ee635e772636dad3f09f78f1ab87.

The commit has some race conditions given how expires is managed on a
fib6_info in relation to gc start, adding the entry to the gc list and
setting the timer value leading to UAF. Revert the commit and try again
in a later release.

Fixes: 3dec89b14d37 ("net/ipv6: Remove expired routes with a separated list of routes")
Cc: Kui-Feng Lee &lt;thinker.li@gmail.com&gt;
Signed-off-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20231219030243.25687-1-dsahern@kernel.org
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 dade3f6a1e4e35a5ae916d5e78b3229ec34c78ec ]

This reverts commit 3dec89b14d37ee635e772636dad3f09f78f1ab87.

The commit has some race conditions given how expires is managed on a
fib6_info in relation to gc start, adding the entry to the gc list and
setting the timer value leading to UAF. Revert the commit and try again
in a later release.

Fixes: 3dec89b14d37 ("net/ipv6: Remove expired routes with a separated list of routes")
Cc: Kui-Feng Lee &lt;thinker.li@gmail.com&gt;
Signed-off-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20231219030243.25687-1-dsahern@kernel.org
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>net: ipv6: support reporting otherwise unknown prefix flags in RTM_NEWPREFIX</title>
<updated>2023-12-20T16:01:45+00:00</updated>
<author>
<name>Maciej Żenczykowski</name>
<email>maze@google.com</email>
</author>
<published>2023-12-06T17:36:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=92d813f73f649a32cb936583030c2edcc309eb37'/>
<id>92d813f73f649a32cb936583030c2edcc309eb37</id>
<content type='text'>
[ Upstream commit bd4a816752bab609dd6d65ae021387beb9e2ddbd ]

Lorenzo points out that we effectively clear all unknown
flags from PIO when copying them to userspace in the netlink
RTM_NEWPREFIX notification.

We could fix this one at a time as new flags are defined,
or in one fell swoop - I choose the latter.

We could either define 6 new reserved flags (reserved1..6) and handle
them individually (and rename them as new flags are defined), or we
could simply copy the entire unmodified byte over - I choose the latter.

This unfortunately requires some anonymous union/struct magic,
so we add a static assert on the struct size for a little extra safety.

Cc: David Ahern &lt;dsahern@kernel.org&gt;
Cc: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&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 bd4a816752bab609dd6d65ae021387beb9e2ddbd ]

Lorenzo points out that we effectively clear all unknown
flags from PIO when copying them to userspace in the netlink
RTM_NEWPREFIX notification.

We could fix this one at a time as new flags are defined,
or in one fell swoop - I choose the latter.

We could either define 6 new reserved flags (reserved1..6) and handle
them individually (and rename them as new flags are defined), or we
could simply copy the entire unmodified byte over - I choose the latter.

This unfortunately requires some anonymous union/struct magic,
so we add a static assert on the struct size for a little extra safety.

Cc: David Ahern &lt;dsahern@kernel.org&gt;
Cc: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&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>ipv6: fix potential NULL deref in fib6_add()</title>
<updated>2023-12-13T17:45:03+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-11-29T16:06:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a08768110a6574e4d994b28f448ca5c016fbf0d4'/>
<id>a08768110a6574e4d994b28f448ca5c016fbf0d4</id>
<content type='text'>
[ Upstream commit 75475bb51e78a3f54ad2f69380f2a1c985e85f2d ]

If fib6_find_prefix() returns NULL, we should silently fallback
using fib6_null_entry regardless of RT6_DEBUG value.

syzbot reported:

WARNING: CPU: 0 PID: 5477 at net/ipv6/ip6_fib.c:1516 fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Modules linked in:
CPU: 0 PID: 5477 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00029-g9b6de136b5f0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Code: 00 48 8b 54 24 68 e8 42 22 00 00 48 85 c0 74 14 49 89 c6 e8 d5 d3 c2 f7 eb 5d e8 ce d3 c2 f7 e9 ca 00 00 00 e8 c4 d3 c2 f7 90 &lt;0f&gt; 0b 90 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 38 80 3c 01 00
RSP: 0018:ffffc90005067740 EFLAGS: 00010293
RAX: ffffffff89cba5bc RBX: ffffc90005067ab0 RCX: ffff88801a2e9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005067980 R08: ffffffff89cbca85 R09: 1ffff110040d4b85
R10: dffffc0000000000 R11: ffffed10040d4b86 R12: 00000000ffffffff
R13: 1ffff110051c3904 R14: ffff8880206a5c00 R15: ffff888028e1c820
FS: 00007f763783c6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f763783bff8 CR3: 000000007f74d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
&lt;TASK&gt;
__ip6_ins_rt net/ipv6/route.c:1303 [inline]
ip6_route_add+0x88/0x120 net/ipv6/route.c:3847
ipv6_route_ioctl+0x525/0x7b0 net/ipv6/route.c:4467
inet6_ioctl+0x21a/0x270 net/ipv6/af_inet6.c:575
sock_do_ioctl+0x152/0x460 net/socket.c:1220
sock_ioctl+0x615/0x8c0 net/socket.c:1339
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82

Fixes: 7bbfe00e0252 ("ipv6: fix general protection fault in fib6_add()")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Wei Wang &lt;weiwan@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20231129160630.3509216-1-edumazet@google.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 75475bb51e78a3f54ad2f69380f2a1c985e85f2d ]

If fib6_find_prefix() returns NULL, we should silently fallback
using fib6_null_entry regardless of RT6_DEBUG value.

syzbot reported:

WARNING: CPU: 0 PID: 5477 at net/ipv6/ip6_fib.c:1516 fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Modules linked in:
CPU: 0 PID: 5477 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00029-g9b6de136b5f0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Code: 00 48 8b 54 24 68 e8 42 22 00 00 48 85 c0 74 14 49 89 c6 e8 d5 d3 c2 f7 eb 5d e8 ce d3 c2 f7 e9 ca 00 00 00 e8 c4 d3 c2 f7 90 &lt;0f&gt; 0b 90 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 38 80 3c 01 00
RSP: 0018:ffffc90005067740 EFLAGS: 00010293
RAX: ffffffff89cba5bc RBX: ffffc90005067ab0 RCX: ffff88801a2e9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005067980 R08: ffffffff89cbca85 R09: 1ffff110040d4b85
R10: dffffc0000000000 R11: ffffed10040d4b86 R12: 00000000ffffffff
R13: 1ffff110051c3904 R14: ffff8880206a5c00 R15: ffff888028e1c820
FS: 00007f763783c6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f763783bff8 CR3: 000000007f74d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
&lt;TASK&gt;
__ip6_ins_rt net/ipv6/route.c:1303 [inline]
ip6_route_add+0x88/0x120 net/ipv6/route.c:3847
ipv6_route_ioctl+0x525/0x7b0 net/ipv6/route.c:4467
inet6_ioctl+0x21a/0x270 net/ipv6/af_inet6.c:575
sock_do_ioctl+0x152/0x460 net/socket.c:1220
sock_ioctl+0x615/0x8c0 net/socket.c:1339
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82

Fixes: 7bbfe00e0252 ("ipv6: fix general protection fault in fib6_add()")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Wei Wang &lt;weiwan@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20231129160630.3509216-1-edumazet@google.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>dccp/tcp: Call security_inet_conn_request() after setting IPv6 addresses.</title>
<updated>2023-11-20T10:59:35+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2023-10-30T20:10:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=82c0c8b9643ed15707412c42a6753085c5a894e6'/>
<id>82c0c8b9643ed15707412c42a6753085c5a894e6</id>
<content type='text'>
[ Upstream commit 23be1e0e2a83a8543214d2599a31d9a2185a796b ]

Initially, commit 4237c75c0a35 ("[MLSXFRM]: Auto-labeling of child
sockets") introduced security_inet_conn_request() in some functions
where reqsk is allocated.  The hook is added just after the allocation,
so reqsk's IPv6 remote address was not initialised then.

However, SELinux/Smack started to read it in netlbl_req_setattr()
after commit e1adea927080 ("calipso: Allow request sockets to be
relabelled by the lsm.").

Commit 284904aa7946 ("lsm: Relocate the IPv4 security_inet_conn_request()
hooks") fixed that kind of issue only in TCPv4 because IPv6 labeling was
not supported at that time.  Finally, the same issue was introduced again
in IPv6.

Let's apply the same fix on DCCPv6 and TCPv6.

Fixes: e1adea927080 ("calipso: Allow request sockets to be relabelled by the lsm.")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt;
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 23be1e0e2a83a8543214d2599a31d9a2185a796b ]

Initially, commit 4237c75c0a35 ("[MLSXFRM]: Auto-labeling of child
sockets") introduced security_inet_conn_request() in some functions
where reqsk is allocated.  The hook is added just after the allocation,
so reqsk's IPv6 remote address was not initialised then.

However, SELinux/Smack started to read it in netlbl_req_setattr()
after commit e1adea927080 ("calipso: Allow request sockets to be
relabelled by the lsm.").

Commit 284904aa7946 ("lsm: Relocate the IPv4 security_inet_conn_request()
hooks") fixed that kind of issue only in TCPv4 because IPv6 labeling was
not supported at that time.  Finally, the same issue was introduced again
in IPv6.

Let's apply the same fix on DCCPv6 and TCPv6.

Fixes: e1adea927080 ("calipso: Allow request sockets to be relabelled by the lsm.")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt;
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>ipv6: avoid atomic fragment on GSO packets</title>
<updated>2023-11-20T10:59:03+00:00</updated>
<author>
<name>Yan Zhai</name>
<email>yan@cloudflare.com</email>
</author>
<published>2023-10-24T14:26:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ee1c730fdd34b82b906fac564fbface968e7931e'/>
<id>ee1c730fdd34b82b906fac564fbface968e7931e</id>
<content type='text'>
[ Upstream commit 03d6c848bfb406e9ef6d9846d759e97beaeea113 ]

When the ipv6 stack output a GSO packet, if its gso_size is larger than
dst MTU, then all segments would be fragmented. However, it is possible
for a GSO packet to have a trailing segment with smaller actual size
than both gso_size as well as the MTU, which leads to an "atomic
fragment". Atomic fragments are considered harmful in RFC-8021. An
Existing report from APNIC also shows that atomic fragments are more
likely to be dropped even it is equivalent to a no-op [1].

Add an extra check in the GSO slow output path. For each segment from
the original over-sized packet, if it fits with the path MTU, then avoid
generating an atomic fragment.

Link: https://www.potaroo.net/presentations/2022-03-01-ipv6-frag.pdf [1]
Fixes: b210de4f8c97 ("net: ipv6: Validate GSO SKB before finish IPv6 processing")
Reported-by: David Wragg &lt;dwragg@cloudflare.com&gt;
Signed-off-by: Yan Zhai &lt;yan@cloudflare.com&gt;
Link: https://lore.kernel.org/r/90912e3503a242dca0bc36958b11ed03a2696e5e.1698156966.git.yan@cloudflare.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 03d6c848bfb406e9ef6d9846d759e97beaeea113 ]

When the ipv6 stack output a GSO packet, if its gso_size is larger than
dst MTU, then all segments would be fragmented. However, it is possible
for a GSO packet to have a trailing segment with smaller actual size
than both gso_size as well as the MTU, which leads to an "atomic
fragment". Atomic fragments are considered harmful in RFC-8021. An
Existing report from APNIC also shows that atomic fragments are more
likely to be dropped even it is equivalent to a no-op [1].

Add an extra check in the GSO slow output path. For each segment from
the original over-sized packet, if it fits with the path MTU, then avoid
generating an atomic fragment.

Link: https://www.potaroo.net/presentations/2022-03-01-ipv6-frag.pdf [1]
Fixes: b210de4f8c97 ("net: ipv6: Validate GSO SKB before finish IPv6 processing")
Reported-by: David Wragg &lt;dwragg@cloudflare.com&gt;
Signed-off-by: Yan Zhai &lt;yan@cloudflare.com&gt;
Link: https://lore.kernel.org/r/90912e3503a242dca0bc36958b11ed03a2696e5e.1698156966.git.yan@cloudflare.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>udplite: fix various data-races</title>
<updated>2023-11-20T10:58:56+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-12T09:17:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=257e8d2e5b7a4c7d6452ebaefef99f3df66fa7a9'/>
<id>257e8d2e5b7a4c7d6452ebaefef99f3df66fa7a9</id>
<content type='text'>
[ Upstream commit 882af43a0fc37e26d85fb0df0c9edd3bed928de4 ]

udp-&gt;pcflag, udp-&gt;pcslen and udp-&gt;pcrlen reads/writes are racy.

Move udp-&gt;pcflag to udp-&gt;udp_flags for atomicity,
and add READ_ONCE()/WRITE_ONCE() annotations for pcslen and pcrlen.

Fixes: ba4e58eca8aa ("[NET]: Supporting UDP-Lite (RFC 3828) in Linux")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
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 882af43a0fc37e26d85fb0df0c9edd3bed928de4 ]

udp-&gt;pcflag, udp-&gt;pcslen and udp-&gt;pcrlen reads/writes are racy.

Move udp-&gt;pcflag to udp-&gt;udp_flags for atomicity,
and add READ_ONCE()/WRITE_ONCE() annotations for pcslen and pcrlen.

Fixes: ba4e58eca8aa ("[NET]: Supporting UDP-Lite (RFC 3828) in Linux")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
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>udplite: remove UDPLITE_BIT</title>
<updated>2023-11-20T10:58:56+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-12T09:17:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=79cb39e7fa41c988181ab9e3bce6a411e8717989'/>
<id>79cb39e7fa41c988181ab9e3bce6a411e8717989</id>
<content type='text'>
[ Upstream commit 729549aa350c56a777bb342941ed4d69b6585769 ]

This flag is set but never read, we can remove it.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 882af43a0fc3 ("udplite: fix various data-races")
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 729549aa350c56a777bb342941ed4d69b6585769 ]

This flag is set but never read, we can remove it.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 882af43a0fc3 ("udplite: fix various data-races")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: annotate data-races around udp-&gt;encap_type</title>
<updated>2023-11-20T10:58:56+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-12T09:17:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4781a75d34c1a9d4cca337afb58b1554fe165928'/>
<id>4781a75d34c1a9d4cca337afb58b1554fe165928</id>
<content type='text'>
[ Upstream commit 70a36f571362a8de8b8c02d21ae524fc776287f2 ]

syzbot/KCSAN complained about UDP_ENCAP_L2TPINUDP setsockopt() racing.

Add READ_ONCE()/WRITE_ONCE() to document races on this lockless field.

syzbot report was:
BUG: KCSAN: data-race in udp_lib_setsockopt / udp_lib_setsockopt

read-write to 0xffff8881083603fa of 1 bytes by task 16557 on cpu 0:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881083603fa of 1 bytes by task 16554 on cpu 1:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -&gt; 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16554 Comm: syz-executor.5 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129e3de #0

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
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 70a36f571362a8de8b8c02d21ae524fc776287f2 ]

syzbot/KCSAN complained about UDP_ENCAP_L2TPINUDP setsockopt() racing.

Add READ_ONCE()/WRITE_ONCE() to document races on this lockless field.

syzbot report was:
BUG: KCSAN: data-race in udp_lib_setsockopt / udp_lib_setsockopt

read-write to 0xffff8881083603fa of 1 bytes by task 16557 on cpu 0:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881083603fa of 1 bytes by task 16554 on cpu 1:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -&gt; 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16554 Comm: syz-executor.5 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129e3de #0

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
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>udp: lockless UDP_ENCAP_L2TPINUDP / UDP_GRO</title>
<updated>2023-11-20T10:58:56+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-12T09:17:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f1f1f5cc1955748b0a844373250bcd8046c762d9'/>
<id>f1f1f5cc1955748b0a844373250bcd8046c762d9</id>
<content type='text'>
[ Upstream commit ac9a7f4ce5dda1472e8f44096f33066c6ec1a3b4 ]

Move udp-&gt;encap_enabled to udp-&gt;udp_flags.

Add udp_test_and_set_bit() helper to allow lockless
udp_tunnel_encap_enable() implementation.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 70a36f571362 ("udp: annotate data-races around udp-&gt;encap_type")
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 ac9a7f4ce5dda1472e8f44096f33066c6ec1a3b4 ]

Move udp-&gt;encap_enabled to udp-&gt;udp_flags.

Add udp_test_and_set_bit() helper to allow lockless
udp_tunnel_encap_enable() implementation.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 70a36f571362 ("udp: annotate data-races around udp-&gt;encap_type")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: move udp-&gt;gro_enabled to udp-&gt;udp_flags</title>
<updated>2023-11-20T10:58:56+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-12T09:17:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=67188b2e28dacddf0d85777eca8ce4c2eadde03a'/>
<id>67188b2e28dacddf0d85777eca8ce4c2eadde03a</id>
<content type='text'>
[ Upstream commit e1dc0615c6b08ef36414f08c011965b8fb56198b ]

syzbot reported that udp-&gt;gro_enabled can be read locklessly.
Use one atomic bit from udp-&gt;udp_flags.

Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
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 e1dc0615c6b08ef36414f08c011965b8fb56198b ]

syzbot reported that udp-&gt;gro_enabled can be read locklessly.
Use one atomic bit from udp-&gt;udp_flags.

Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
