Commit Graph

230 Commits

Author SHA1 Message Date
Kuniyuki Iwashima
b45a337f06 inet6: Clean up failure path in do_ipv6_setsockopt().
We can reuse the unlock label above and need not repeat the same code.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-24 09:40:39 +01:00
Kuniyuki Iwashima
f49cd2f4d6 tcp: Fix data races around icsk->icsk_af_ops.
setsockopt(IPV6_ADDRFORM) and tcp_v6_connect() change icsk->icsk_af_ops
under lock_sock(), but tcp_(get|set)sockopt() read it locklessly.  To
avoid load/store tearing, we need to add READ_ONCE() and WRITE_ONCE()
for the reads and writes.

Thanks to Eric Dumazet for providing the syzbot report:

BUG: KCSAN: data-race in tcp_setsockopt / tcp_v6_connect

write to 0xffff88813c624518 of 8 bytes by task 23936 on cpu 0:
tcp_v6_connect+0x5b3/0xce0 net/ipv6/tcp_ipv6.c:240
__inet_stream_connect+0x159/0x6d0 net/ipv4/af_inet.c:660
inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724
__sys_connect_file net/socket.c:1976 [inline]
__sys_connect+0x197/0x1b0 net/socket.c:1993
__do_sys_connect net/socket.c:2003 [inline]
__se_sys_connect net/socket.c:2000 [inline]
__x64_sys_connect+0x3d/0x50 net/socket.c:2000
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813c624518 of 8 bytes by task 23937 on cpu 1:
tcp_setsockopt+0x147/0x1c80 net/ipv4/tcp.c:3789
sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3585
__sys_setsockopt+0x212/0x2b0 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263 [inline]
__se_sys_setsockopt net/socket.c:2260 [inline]
__x64_sys_setsockopt+0x62/0x70 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffffffff8539af68 -> 0xffffffff8539aff8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23937 Comm: syz-executor.5 Not tainted
6.0.0-rc4-syzkaller-00331-g4ed9c1e971b1-dirty #0

Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 08/26/2022

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-12 17:50:37 -07:00
Kuniyuki Iwashima
364f997b5c ipv6: Fix data races around sk->sk_prot.
Commit 086d49058c ("ipv6: annotate some data-races around sk->sk_prot")
fixed some data-races around sk->sk_prot but it was not enough.

Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot
without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid
load tearing.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-12 17:50:37 -07:00
Kuniyuki Iwashima
21985f4337 udp: Call inet6_destroy_sock() in setsockopt(IPV6_ADDRFORM).
Commit 4b340ae20d ("IPv6: Complete IPV6_DONTFRAG support") forgot
to add a change to free inet6_sk(sk)->rxpmtu while converting an IPv6
socket into IPv4 with IPV6_ADDRFORM.  After conversion, sk_prot is
changed to udp_prot and ->destroy() never cleans it up, resulting in
a memory leak.

This is due to the discrepancy between inet6_destroy_sock() and
IPV6_ADDRFORM, so let's call inet6_destroy_sock() from IPV6_ADDRFORM
to remove the difference.

However, this is not enough for now because rxpmtu can be changed
without lock_sock() after commit 03485f2adc ("udpv6: Add lockless
sendmsg() support").  We will fix this case in the following patch.

Note we will rename inet6_destroy_sock() to inet6_cleanup_sock() and
remove unnecessary inet6_destroy_sock() calls in sk_prot->destroy()
in the future.

Fixes: 4b340ae20d ("IPv6: Complete IPV6_DONTFRAG support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-12 17:50:37 -07:00
Kuniyuki Iwashima
3c52c6bb83 tcp/udp: Fix memory leak in ipv6_renew_options().
syzbot reported a memory leak [0] related to IPV6_ADDRFORM.

The scenario is that while one thread is converting an IPv6 socket into
IPv4 with IPV6_ADDRFORM, another thread calls do_ipv6_setsockopt() and
allocates memory to inet6_sk(sk)->XXX after conversion.

Then, the converted sk with (tcp|udp)_prot never frees the IPv6 resources,
which inet6_destroy_sock() should have cleaned up.

setsockopt(IPV6_ADDRFORM)                 setsockopt(IPV6_DSTOPTS)
+-----------------------+                 +----------------------+
- do_ipv6_setsockopt(sk, ...)
  - sockopt_lock_sock(sk)                 - do_ipv6_setsockopt(sk, ...)
    - lock_sock(sk)                         ^._ called via tcpv6_prot
  - WRITE_ONCE(sk->sk_prot, &tcp_prot)          before WRITE_ONCE()
  - xchg(&np->opt, NULL)
  - txopt_put(opt)
  - sockopt_release_sock(sk)
    - release_sock(sk)                      - sockopt_lock_sock(sk)
                                              - lock_sock(sk)
                                            - ipv6_set_opt_hdr(sk, ...)
                                              - ipv6_update_options(sk, opt)
                                                - xchg(&inet6_sk(sk)->opt, opt)
                                                  ^._ opt is never freed.

                                            - sockopt_release_sock(sk)
                                              - release_sock(sk)

Since IPV6_DSTOPTS allocates options under lock_sock(), we can avoid this
memory leak by testing whether sk_family is changed by IPV6_ADDRFORM after
acquiring the lock.

This issue exists from the initial commit between IPV6_ADDRFORM and
IPV6_PKTOPTIONS.

[0]:
BUG: memory leak
unreferenced object 0xffff888009ab9f80 (size 96):
  comm "syz-executor583", pid 328, jiffies 4294916198 (age 13.034s)
  hex dump (first 32 bytes):
    01 00 00 00 48 00 00 00 08 00 00 00 00 00 00 00  ....H...........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000002ee98ae1>] kmalloc include/linux/slab.h:605 [inline]
    [<000000002ee98ae1>] sock_kmalloc+0xb3/0x100 net/core/sock.c:2566
    [<0000000065d7b698>] ipv6_renew_options+0x21e/0x10b0 net/ipv6/exthdrs.c:1318
    [<00000000a8c756d7>] ipv6_set_opt_hdr net/ipv6/ipv6_sockglue.c:354 [inline]
    [<00000000a8c756d7>] do_ipv6_setsockopt.constprop.0+0x28b7/0x4350 net/ipv6/ipv6_sockglue.c:668
    [<000000002854d204>] ipv6_setsockopt+0xdf/0x190 net/ipv6/ipv6_sockglue.c:1021
    [<00000000e69fdcf8>] tcp_setsockopt+0x13b/0x2620 net/ipv4/tcp.c:3789
    [<0000000090da4b9b>] __sys_setsockopt+0x239/0x620 net/socket.c:2252
    [<00000000b10d192f>] __do_sys_setsockopt net/socket.c:2263 [inline]
    [<00000000b10d192f>] __se_sys_setsockopt net/socket.c:2260 [inline]
    [<00000000b10d192f>] __x64_sys_setsockopt+0xbe/0x160 net/socket.c:2260
    [<000000000a80d7aa>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    [<000000000a80d7aa>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
    [<000000004562b5c6>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-12 17:50:37 -07:00
Paolo Abeni
2786bcff28 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-09-05

The following pull-request contains BPF updates for your *net-next* tree.

We've added 106 non-merge commits during the last 18 day(s) which contain
a total of 159 files changed, 5225 insertions(+), 1358 deletions(-).

There are two small merge conflicts, resolve them as follows:

1) tools/testing/selftests/bpf/DENYLIST.s390x

  Commit 27e23836ce ("selftests/bpf: Add lru_bug to s390x deny list") in
  bpf tree was needed to get BPF CI green on s390x, but it conflicted with
  newly added tests on bpf-next. Resolve by adding both hunks, result:

  [...]
  lru_bug                                  # prog 'printk': failed to auto-attach: -524
  setget_sockopt                           # attach unexpected error: -524                                               (trampoline)
  cb_refs                                  # expected error message unexpected error: -524                               (trampoline)
  cgroup_hierarchical_stats                # JIT does not support calling kernel function                                (kfunc)
  htab_update                              # failed to attach: ERROR: strerror_r(-524)=22                                (trampoline)
  [...]

2) net/core/filter.c

  Commit 1227c1771d ("net: Fix data-races around sysctl_[rw]mem_(max|default).")
  from net tree conflicts with commit 29003875bd ("bpf: Change bpf_setsockopt(SOL_SOCKET)
  to reuse sk_setsockopt()") from bpf-next tree. Take the code as it is from
  bpf-next tree, result:

  [...]
	if (getopt) {
		if (optname == SO_BINDTODEVICE)
			return -EINVAL;
		return sk_getsockopt(sk, SOL_SOCKET, optname,
				     KERNEL_SOCKPTR(optval),
				     KERNEL_SOCKPTR(optlen));
	}

	return sk_setsockopt(sk, SOL_SOCKET, optname,
			     KERNEL_SOCKPTR(optval), *optlen);
  [...]

The main changes are:

1) Add any-context BPF specific memory allocator which is useful in particular for BPF
   tracing with bonus of performance equal to full prealloc, from Alexei Starovoitov.

2) Big batch to remove duplicated code from bpf_{get,set}sockopt() helpers as an effort
   to reuse the existing core socket code as much as possible, from Martin KaFai Lau.

3) Extend BPF flow dissector for BPF programs to just augment the in-kernel dissector
   with custom logic. In other words, allow for partial replacement, from Shmulik Ladkani.

4) Add a new cgroup iterator to BPF with different traversal options, from Hao Luo.

5) Support for BPF to collect hierarchical cgroup statistics efficiently through BPF
   integration with the rstat framework, from Yosry Ahmed.

6) Support bpf_{g,s}et_retval() under more BPF cgroup hooks, from Stanislav Fomichev.

7) BPF hash table and local storages fixes under fully preemptible kernel, from Hou Tao.

8) Add various improvements to BPF selftests and libbpf for compilation with gcc BPF
   backend, from James Hilliard.

9) Fix verifier helper permissions and reference state management for synchronous
   callbacks, from Kumar Kartikeya Dwivedi.

10) Add support for BPF selftest's xskxceiver to also be used against real devices that
    support MAC loopback, from Maciej Fijalkowski.

11) Various fixes to the bpf-helpers(7) man page generation script, from Quentin Monnet.

12) Document BPF verifier's tnum_in(tnum_range(), ...) gotchas, from Shung-Hsi Yu.

13) Various minor misc improvements all over the place.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (106 commits)
  bpf: Optimize rcu_barrier usage between hash map and bpf_mem_alloc.
  bpf: Remove usage of kmem_cache from bpf_mem_cache.
  bpf: Remove prealloc-only restriction for sleepable bpf programs.
  bpf: Prepare bpf_mem_alloc to be used by sleepable bpf programs.
  bpf: Remove tracing program restriction on map types
  bpf: Convert percpu hash map to per-cpu bpf_mem_alloc.
  bpf: Add percpu allocation support to bpf_mem_alloc.
  bpf: Batch call_rcu callbacks instead of SLAB_TYPESAFE_BY_RCU.
  bpf: Adjust low/high watermarks in bpf_mem_cache
  bpf: Optimize call_rcu in non-preallocated hash map.
  bpf: Optimize element count in non-preallocated hash map.
  bpf: Relax the requirement to use preallocated hash maps in tracing progs.
  samples/bpf: Reduce syscall overhead in map_perf_test.
  selftests/bpf: Improve test coverage of test_maps
  bpf: Convert hash map to bpf_mem_alloc.
  bpf: Introduce any context BPF specific memory allocator.
  selftest/bpf: Add test for bpf_getsockopt()
  bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt()
  bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt()
  bpf: Change bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt()
  ...
====================

Link: https://lore.kernel.org/r/20220905161136.9150-1-daniel@iogearbox.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-06 23:21:18 +02:00
Martin KaFai Lau
38566ec06f bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt()
This patch changes bpf_getsockopt(SOL_IPV6) to reuse
do_ipv6_getsockopt().  It removes the duplicated code from
bpf_getsockopt(SOL_IPV6).

This also makes bpf_getsockopt(SOL_IPV6) supporting the same
set of optnames as in bpf_setsockopt(SOL_IPV6).  In particular,
this adds IPV6_AUTOFLOWLABEL support to bpf_getsockopt(SOL_IPV6).

ipv6 could be compiled as a module.  Like how other code solved it
with stubs in ipv6_stubs.h, this patch adds the do_ipv6_getsockopt
to the ipv6_bpf_stub.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002931.2896218-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-02 20:34:32 -07:00
Martin KaFai Lau
0f95f7d426 bpf: net: Avoid do_ipv6_getsockopt() taking sk lock when called from bpf
Similar to the earlier patch that changes sk_getsockopt() to
use sockopt_{lock,release}_sock() such that it can avoid taking the
lock when called from bpf.  This patch also changes do_ipv6_getsockopt()
to use sockopt_{lock,release}_sock() such that bpf_getsockopt(SOL_IPV6)
can reuse do_ipv6_getsockopt().

Although bpf_getsockopt(SOL_IPV6) currently does not support optname
that requires lock_sock(), using sockopt_{lock,release}_sock()
consistently across *_getsockopt() will make future optname addition
harder to miss the sockopt_{lock,release}_sock() usage. eg. when
adding new optname that requires a lock and the new optname is
needed in bpf_getsockopt() also.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002859.2893064-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-02 20:34:31 -07:00
Martin KaFai Lau
6dadbe4bac bpf: net: Change do_ipv6_getsockopt() to take the sockptr_t argument
Similar to the earlier patch that changes sk_getsockopt() to
take the sockptr_t argument .  This patch also changes
do_ipv6_getsockopt() to take the sockptr_t argument such that
a latter patch can make bpf_getsockopt(SOL_IPV6) to reuse
do_ipv6_getsockopt().

Note on the change in ip6_mc_msfget().  This function is to
return an array of sockaddr_storage in optval.  This function
is shared between ipv6_get_msfilter() and compat_ipv6_get_msfilter().
However, the sockaddr_storage is stored at different offset of the
optval because of the difference between group_filter and
compat_group_filter.  Thus, a new 'ss_offset' argument is
added to ip6_mc_msfget().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002853.2892532-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-02 20:34:31 -07:00
Martin KaFai Lau
9c3f9707de net: Add a len argument to compat_ipv6_get_msfilter()
Pass the len to the compat_ipv6_get_msfilter() instead of
compat_ipv6_get_msfilter() getting it again from optlen.
Its counter part ipv6_get_msfilter() is also taking the
len from do_ipv6_getsockopt().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002846.2892091-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-02 20:34:31 -07:00
Martin KaFai Lau
75f2397988 net: Remove unused flags argument from do_ipv6_getsockopt
The 'unsigned int flags' argument is always 0, so it can be removed.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002840.2891763-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-02 20:34:31 -07:00
Kuniyuki Iwashima
7de6d09f51 net: Fix data-races around sysctl_optmem_max.
While reading sysctl_optmem_max, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24 13:46:57 +01:00
Martin KaFai Lau
75b64b68ee bpf: Change bpf_setsockopt(SOL_IPV6) to reuse do_ipv6_setsockopt()
After the prep work in the previous patches,
this patch removes the dup code from bpf_setsockopt(SOL_IPV6)
and reuses the implementation in do_ipv6_setsockopt().

ipv6 could be compiled as a module.  Like how other code solved it
with stubs in ipv6_stubs.h, this patch adds the do_ipv6_setsockopt
to the ipv6_bpf_stub.

The current bpf_setsockopt(IPV6_TCLASS) does not take the
INET_ECN_MASK into the account for tcp.  The
do_ipv6_setsockopt(IPV6_TCLASS) will handle it correctly.

The existing optname white-list is refactored into a new
function sol_ipv6_setsockopt().

After this last SOL_IPV6 dup code removal, the __bpf_setsockopt()
is simplified enough that the extra "{ }" around the if statement
can be removed.

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220817061834.4181198-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-18 17:06:13 -07:00
Martin KaFai Lau
40cd308ea5 bpf: net: Change do_ipv6_setsockopt() to use the sockopt's lock_sock() and capable()
Similar to the earlier patch that avoids sk_setsockopt() from
taking sk lock and doing capable test when called by bpf.  This patch
changes do_ipv6_setsockopt() to use the sockopt_{lock,release}_sock()
and sockopt_[ns_]capable().

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220817061744.4176893-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-18 17:06:13 -07:00
Eric Dumazet
086d49058c ipv6: annotate some data-races around sk->sk_prot
IPv6 has this hack changing sk->sk_prot when an IPv6 socket
is 'converted' to an IPv4 one with IPV6_ADDRFORM option.

This operation is only performed for TCP and UDP, knowing
their 'struct proto' for the two network families are populated
in the same way, and can not disappear while a reader
might use and dereference sk->sk_prot.

If we think about it all reads of sk->sk_prot while
either socket lock or RTNL is not acquired should be using READ_ONCE().

Also note that other layers like MPTCP, XFRM, CHELSIO_TLS also
write over sk->sk_prot.

BUG: KCSAN: data-race in inet6_recvmsg / ipv6_setsockopt

write to 0xffff8881386f7aa8 of 8 bytes by task 26932 on cpu 0:
 do_ipv6_setsockopt net/ipv6/ipv6_sockglue.c:492 [inline]
 ipv6_setsockopt+0x3758/0x3910 net/ipv6/ipv6_sockglue.c:1019
 udpv6_setsockopt+0x85/0x90 net/ipv6/udp.c:1649
 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3489
 __sys_setsockopt+0x209/0x2a0 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2188
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881386f7aa8 of 8 bytes by task 26911 on cpu 1:
 inet6_recvmsg+0x7a/0x210 net/ipv6/af_inet6.c:659
 ____sys_recvmsg+0x16c/0x320
 ___sys_recvmsg net/socket.c:2674 [inline]
 do_recvmmsg+0x3f5/0xae0 net/socket.c:2768
 __sys_recvmmsg net/socket.c:2847 [inline]
 __do_sys_recvmmsg net/socket.c:2870 [inline]
 __se_sys_recvmmsg net/socket.c:2863 [inline]
 __x64_sys_recvmmsg+0xde/0x160 net/socket.c:2863
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffffffff85e0e980 -> 0xffffffff85e01580

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 26911 Comm: syz-executor.3 Not tainted 5.17.0-rc2-syzkaller-00316-g0457e5153e0e-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-18 11:53:28 +00:00
Maciej Żenczykowski
305e95bb89 net-ipv6: changes to ->tclass (via IPV6_TCLASS) should sk_dst_reset()
This is to match ipv4 behaviour, see __ip_sock_set_tos()
implementation.

Technically for ipv6 this might not be required because normally we
do not allow tclass to influence routing, yet the cli tooling does
support it:

lpk11:~# ip -6 rule add pref 5 tos 45 lookup 5
lpk11:~# ip -6 rule
5:      from all tos 0x45 lookup 5

and in general dscp/tclass based routing does make sense.

We already have cases where dscp can affect vlan priority and/or
transmit queue (especially on wifi).

So let's just make things match.  Easier to reason about and no harm.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Link: https://lore.kernel.org/r/20211123223208.1117871-1-zenczykowski@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-24 18:57:23 -08:00
Maciej Żenczykowski
9f7b3a69c8 net-ipv6: do not allow IPV6_TCLASS to muck with tcp's ECN
This is to match ipv4 behaviour, see __ip_sock_set_tos()
implementation at ipv4/ip_sockglue.c:579

void __ip_sock_set_tos(struct sock *sk, int val)
{
  if (sk->sk_type == SOCK_STREAM) {
    val &= ~INET_ECN_MASK;
    val |= inet_sk(sk)->tos & INET_ECN_MASK;
  }
  if (inet_sk(sk)->tos != val) {
    inet_sk(sk)->tos = val;
    sk->sk_priority = rt_tos2priority(val);
    sk_dst_reset(sk);
  }
}

Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20211123223154.1117794-1-zenczykowski@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-24 18:57:14 -08:00
Eric Dumazet
b3cb764aa1 net: drop nopreempt requirement on sock_prot_inuse_add()
This is distracting really, let's make this simpler,
because many callers had to take care of this
by themselves, even if on x86 this adds more
code than really needed.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:20:45 +00:00
Eric Dumazet
790eb67374 ipv6: guard IPV6_MINHOPCOUNT with a static key
RFC 5082 IPV6_MINHOPCOUNT is rarely used on hosts.

Add a static key to remove from TCP fast path useless code,
and potential cache line miss to fetch tcp_inet6_sk(sk)->min_hopcount

Note that once ip6_min_hopcount static key has been enabled,
it stays enabled until next boot.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25 18:02:13 -07:00
Eric Dumazet
cc17c3c8e8 ipv6: annotate data races around np->min_hopcount
No report yet from KCSAN, yet worth documenting the races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25 18:02:13 -07:00
Gustavo A. R. Silva
db243b7964 net/ipv4/ipv6: Replace one-element arraya with flexible-array members
There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

Use an anonymous union with a couple of anonymous structs in order to
keep userspace unchanged and refactor the related code accordingly:

$ pahole -C group_filter net/ipv4/ip_sockglue.o
struct group_filter {
	union {
		struct {
			__u32      gf_interface_aux;     /*     0     4 */

			/* XXX 4 bytes hole, try to pack */

			struct __kernel_sockaddr_storage gf_group_aux; /*     8   128 */
			/* --- cacheline 2 boundary (128 bytes) was 8 bytes ago --- */
			__u32      gf_fmode_aux;         /*   136     4 */
			__u32      gf_numsrc_aux;        /*   140     4 */
			struct __kernel_sockaddr_storage gf_slist[1]; /*   144   128 */
		};                                       /*     0   272 */
		struct {
			__u32      gf_interface;         /*     0     4 */

			/* XXX 4 bytes hole, try to pack */

			struct __kernel_sockaddr_storage gf_group; /*     8   128 */
			/* --- cacheline 2 boundary (128 bytes) was 8 bytes ago --- */
			__u32      gf_fmode;             /*   136     4 */
			__u32      gf_numsrc;            /*   140     4 */
			struct __kernel_sockaddr_storage gf_slist_flex[0]; /*   144     0 */
		};                                       /*     0   144 */
	};                                               /*     0   272 */

	/* size: 272, cachelines: 5, members: 1 */
	/* last cacheline: 16 bytes */
};

$ pahole -C compat_group_filter net/ipv4/ip_sockglue.o
struct compat_group_filter {
	union {
		struct {
			__u32      gf_interface_aux;     /*     0     4 */
			struct __kernel_sockaddr_storage gf_group_aux __attribute__((__aligned__(4))); /*     4   128 */
			/* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */
			__u32      gf_fmode_aux;         /*   132     4 */
			__u32      gf_numsrc_aux;        /*   136     4 */
			struct __kernel_sockaddr_storage gf_slist[1] __attribute__((__aligned__(4))); /*   140   128 */
		} __attribute__((__packed__)) __attribute__((__aligned__(4)));                     /*     0   268 */
		struct {
			__u32      gf_interface;         /*     0     4 */
			struct __kernel_sockaddr_storage gf_group __attribute__((__aligned__(4))); /*     4   128 */
			/* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */
			__u32      gf_fmode;             /*   132     4 */
			__u32      gf_numsrc;            /*   136     4 */
			struct __kernel_sockaddr_storage gf_slist_flex[0] __attribute__((__aligned__(4))); /*   140     0 */
		} __attribute__((__packed__)) __attribute__((__aligned__(4)));                     /*     0   140 */
	} __attribute__((__aligned__(1)));               /*     0   268 */

	/* size: 268, cachelines: 5, members: 1 */
	/* forced alignments: 1 */
	/* last cacheline: 12 bytes */
} __attribute__((__packed__));

This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05 11:46:42 +01:00
Lukas Bulwahn
9e39394fae net/ipv6: propagate user pointer annotation
For IPV6_2292PKTOPTIONS, do_ipv6_getsockopt() stores the user pointer
optval in the msg_control field of the msghdr.

Hence, sparse rightfully warns at ./net/ipv6/ipv6_sockglue.c:1151:33:

  warning: incorrect type in assignment (different address spaces)
      expected void *msg_control
      got char [noderef] __user *optval

Since commit 1f466e1f15 ("net: cleanly handle kernel vs user buffers for
->msg_control"), user pointers shall be stored in the msg_control_user
field, and kernel pointers in the msg_control field. This allows to
propagate __user annotations nicely through this struct.

Store optval in msg_control_user to properly record and propagate the
memory space annotation of this pointer.

Note that msg_control_is_user is set to true, so the key invariant, i.e.,
use msg_control_user if and only if msg_control_is_user is true, holds.

The msghdr is further used in the six alternative put_cmsg() calls, with
msg_control_is_user being true, put_cmsg() picks msg_control_user
preserving the __user annotation and passes that properly to
copy_to_user().

No functional change. No change in object code.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20201127093421.21673-1-lukas.bulwahn@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01 11:42:33 -08:00
David S. Miller
bd0b33b248 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Resolved kernel/bpf/btf.c using instructions from merge commit
69138b34a7

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-02 01:02:12 -07:00
Cong Wang
8c0de6e96c ipv6: fix memory leaks on IPV6_ADDRFORM path
IPV6_ADDRFORM causes resource leaks when converting an IPv6 socket
to IPv4, particularly struct ipv6_ac_socklist. Similar to
struct ipv6_mc_socklist, we should just close it on this path.

This bug can be easily reproduced with the following C program:

  #include <stdio.h>
  #include <string.h>
  #include <sys/types.h>
  #include <sys/socket.h>
  #include <arpa/inet.h>

  int main()
  {
    int s, value;
    struct sockaddr_in6 addr;
    struct ipv6_mreq m6;

    s = socket(AF_INET6, SOCK_DGRAM, 0);
    addr.sin6_family = AF_INET6;
    addr.sin6_port = htons(5000);
    inet_pton(AF_INET6, "::ffff:192.168.122.194", &addr.sin6_addr);
    connect(s, (struct sockaddr *)&addr, sizeof(addr));

    inet_pton(AF_INET6, "fe80::AAAA", &m6.ipv6mr_multiaddr);
    m6.ipv6mr_interface = 5;
    setsockopt(s, SOL_IPV6, IPV6_JOIN_ANYCAST, &m6, sizeof(m6));

    value = AF_INET;
    setsockopt(s, SOL_IPV6, IPV6_ADDRFORM, &value, sizeof(value));

    close(s);
    return 0;
  }

Reported-by: ch3332xr@gmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30 16:30:55 -07:00
Willem de Bruijn
01370434df icmp6: support rfc 4884
Extend the rfc 4884 read interface introduced for ipv4 in
commit eba75c587e ("icmp: support rfc 4884") to ipv6.

Add socket option SOL_IPV6/IPV6_RECVERR_RFC4884.

Changes v1->v2:
  - make ipv6_icmp_error_rfc4884 static (file scope)

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 17:12:41 -07:00
Christoph Hellwig
a7b75c5a8c net: pass a sockptr_t into ->setsockopt
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer.  This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
894cfbc0cf net/ipv6: switch do_ipv6_setsockopt to sockptr_t
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
b84d2b73af net/ipv6: factor out a ipv6_set_opt_hdr helper
Factour out a helper to set the IPv6 option headers from
do_ipv6_setsockopt.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
86298285c9 net/ipv6: switch ipv6_flowlabel_opt to sockptr_t
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Note that the get case is pretty weird in that it actually copies data
back to userspace from setsockopt.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
b43c615313 net/ipv6: switch ip6_mroute_setsockopt to sockptr_t
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
c2f12630c6 netfilter: switch nf_setsockopt to sockptr_t
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Christoph Hellwig
c6d1b26a8f net/xfrm: switch xfrm_user_policy to sockptr_t
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:53 -07:00
Christoph Hellwig
3021ad5299 net/ipv6: remove compat_ipv6_{get,set}sockopt
Handle the few cases that need special treatment in-line using
in_compat_syscall().  This also removes all the now unused
compat_{get,set}sockopt methods.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:41 -07:00
Christoph Hellwig
fdf5bdd87c net/ipv6: factor out mcast join/leave setsockopt helpers
Factor out one helper each for setting the native and compat
version of the MCAST_MSFILTER option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:41 -07:00
Christoph Hellwig
ca0e65eb29 net/ipv6: factor out MCAST_MSFILTER setsockopt helpers
Factor out one helper each for setting the native and compat
version of the MCAST_MSFILTER option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:41 -07:00
Christoph Hellwig
d5541e85cd net/ipv6: factor out MCAST_MSFILTER getsockopt helpers
Factor out one helper each for getting the native and compat
version of the MCAST_MSFILTER option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:41 -07:00
Christoph Hellwig
77d4df41d5 netfilter: remove the compat_{get,set} methods
All instances handle compat sockopts via in_compat_syscall() now, so
remove the compat_{get,set} methods as well as the
compat_nf_{get,set}sockopt wrappers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:40 -07:00
Christoph Hellwig
8c918ffbba net: remove compat_sock_common_{get,set}sockopt
Add the compat handling to sock_common_{get,set}sockopt instead,
keyed of in_compat_syscall().  This allow to remove the now unused
->compat_{get,set}sockopt methods from struct proto_ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:40 -07:00
Ahmed Abdelsalam
bb986a5042 seg6: fix seg6_validate_srh() to avoid slab-out-of-bounds
The seg6_validate_srh() is used to validate SRH for three cases:

case1: SRH of data-plane SRv6 packets to be processed by the Linux kernel.
Case2: SRH of the netlink message received  from user-space (iproute2)
Case3: SRH injected into packets through setsockopt

In case1, the SRH can be encoded in the Reduced way (i.e., first SID is
carried in DA only and not represented as SID in the SRH) and the
seg6_validate_srh() now handles this case correctly.

In case2 and case3, the SRH shouldn’t be encoded in the Reduced way
otherwise we lose the first segment (i.e., the first hop).

The current implementation of the seg6_validate_srh() allow SRH of case2
and case3 to be encoded in the Reduced way. This leads a slab-out-of-bounds
problem.

This patch verifies SRH of case1, case2 and case3. Allowing case1 to be
reduced while preventing SRH of case2 and case3 from being reduced .

Reported-by: syzbot+e8c028b62439eac42073@syzkaller.appspotmail.com
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 0cb7498f23 ("seg6: fix SRH processing to comply with RFC8754")
Signed-off-by: Ahmed Abdelsalam <ahabdels@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-04 15:39:32 -07:00
Hangbin Liu
79a1f0ccdb ipv6: fix IPV6_ADDRFORM operation logic
Socket option IPV6_ADDRFORM supports UDP/UDPLITE and TCP at present.
Previously the checking logic looks like:
if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
	do_some_check;
else if (sk->sk_protocol != IPPROTO_TCP)
	break;

After commit b6f6118901 ("ipv6: restrict IPV6_ADDRFORM operation"), TCP
was blocked as the logic changed to:
if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
	do_some_check;
else if (sk->sk_protocol == IPPROTO_TCP)
	do_some_check;
	break;
else
	break;

Then after commit 82c9ae4408 ("ipv6: fix restrict IPV6_ADDRFORM operation")
UDP/UDPLITE were blocked as the logic changed to:
if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
	do_some_check;
if (sk->sk_protocol == IPPROTO_TCP)
	do_some_check;

if (sk->sk_protocol != IPPROTO_TCP)
	break;

Fix it by using Eric's code and simply remove the break in TCP check, which
looks like:
if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE)
	do_some_check;
else if (sk->sk_protocol == IPPROTO_TCP)
	do_some_check;
else
	break;

Fixes: 82c9ae4408 ("ipv6: fix restrict IPV6_ADDRFORM operation")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-01 15:47:04 -07:00
Christoph Hellwig
18d5ad6232 ipv6: add ip6_sock_set_addr_preferences
Add a helper to directly set the IPV6_ADD_PREFERENCES sockopt from kernel
space without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:46 -07:00
Al Viro
b212c322c8 handle the group_source_req options directly
Native ->setsockopt() handling of these options (MCAST_..._SOURCE_GROUP
and MCAST_{,UN}BLOCK_SOURCE) consists of copyin + call of a helper that
does the actual work.  The only change needed for ->compat_setsockopt()
is a slightly different copyin - the helpers can be reused as-is.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:32 -04:00
Al Viro
fcfa0b09d3 ipv6: take handling of group_source_req options into a helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:31 -04:00
Al Viro
2f984f11fd ipv[46]: do compat setsockopt for MCAST_{JOIN,LEAVE}_GROUP directly
direct parallel to the way these two are handled in the native
->setsockopt() instances - the helpers that do the real work
are already separated and can be reused as-is in this case.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:30 -04:00
Al Viro
168a2cca81 ipv6: do compat setsockopt for MCAST_MSFILTER directly
similar to the ipv4 counterpart of that patch - the same
trick used to align the tail array properly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:29 -04:00
Al Viro
d59eb177c8 ip6_mc_msfilter(): pass the address list separately
that way we'll be able to reuse it for compat case

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:29 -04:00
Al Viro
0dfe6581a7 get rid of compat_mc_getsockopt()
now we can do MCAST_MSFILTER in compat ->getsockopt() without
playing silly buggers with copying things back and forth.
We can form a native struct group_filter (sans the variable-length
tail) on stack, pass that + pointer to the tail of original request
to the helper doing the bulk of the work, then do the rest of
copyout - same as the native getsockopt() does.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:27 -04:00
Al Viro
931ca7ab7f ip*_mc_gsfget(): lift copyout of struct group_filter into callers
pass the userland pointer to the array in its tail, so that part
gets copied out by our functions; copyout of everything else is
done in the callers.  Rationale: reuse for compat; the array
is the same in native and compat, the layout of parts before it
is different for compat.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:27 -04:00
Al Viro
e9c375fb5e compat_ip{,v6}_setsockopt(): enumerate MCAST_... options explicitly
We want to check if optname is among the MCAST_... ones; do that as
an explicit switch.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:26 -04:00
Christoph Hellwig
1b2f08df0a ipv6: set msg_control_is_user in do_ipv6_getsockopt
While do_ipv6_getsockopt does not call the high-level recvmsg helper,
the msghdr eventually ends up being passed to put_cmsg anyway, and thus
needs msg_control_is_user set to the proper value.

Fixes: 1f466e1f15 ("net: cleanly handle kernel vs user buffers for ->msg_control")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-13 13:11:45 -07:00