linux-stable.git/net/core, branch v6.9.6

sock_map: avoid race between sock_map_close and sk_psock_put

2024-06-21T12:40:32+00:00

commit 4b4647add7d3c8530493f7247d11e257ee425bf0 upstream.

sk_psock_get will return NULL if the refcount of psock has gone to 0, which
will happen when the last call of sk_psock_put is done. However,
sk_psock_drop may not have finished yet, so the close callback will still
point to sock_map_close despite psock being NULL.

This can be reproduced with a thread deleting an element from the sock map,
while the second one creates a socket, adds it to the map and closes it.

That will trigger the WARN_ON_ONCE:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 7220 at net/core/sock_map.c:1701 sock_map_close+0x2a2/0x2d0 net/core/sock_map.c:1701
Modules linked in:
CPU: 1 PID: 7220 Comm: syz-executor380 Not tainted 6.9.0-syzkaller-07726-g3c999d1ae3c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:sock_map_close+0x2a2/0x2d0 net/core/sock_map.c:1701
Code: df e8 92 29 88 f8 48 8b 1b 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 79 29 88 f8 4c 8b 23 eb 89 e8 4f 15 23 f8 90 <0f> 0b 90 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d e9 13 26 3d 02
RSP: 0018:ffffc9000441fda8 EFLAGS: 00010293
RAX: ffffffff89731ae1 RBX: ffffffff94b87540 RCX: ffff888029470000
RDX: 0000000000000000 RSI: ffffffff8bcab5c0 RDI: ffffffff8c1faba0
RBP: 0000000000000000 R08: ffffffff92f9b61f R09: 1ffffffff25f36c3
R10: dffffc0000000000 R11: fffffbfff25f36c4 R12: ffffffff89731840
R13: ffff88804b587000 R14: ffff88804b587000 R15: ffffffff89731870
FS:  000055555e080380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000207d4000 CR4: 0000000000350ef0
Call Trace:
 
 unix_release+0x87/0xc0 net/unix/af_unix.c:1048
 __sock_release net/socket.c:659 [inline]
 sock_close+0xbe/0x240 net/socket.c:1421
 __fput+0x42b/0x8a0 fs/file_table.c:422
 __do_sys_close fs/open.c:1556 [inline]
 __se_sys_close fs/open.c:1541 [inline]
 __x64_sys_close+0x7f/0x110 fs/open.c:1541
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb37d618070
Code: 00 00 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d4 e8 10 2c 00 00 80 3d 31 f0 07 00 00 74 17 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c
RSP: 002b:00007ffcd4a525d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fb37d618070
RDX: 0000000000000010 RSI: 00000000200001c0 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000100000000 R09: 0000000100000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 

Use sk_psock, which will only check that the pointer is not been set to
NULL yet, which should only happen after the callbacks are restored. If,
then, a reference can still be gotten, we may call sk_psock_stop and cancel
psock->work.

As suggested by Paolo Abeni, reorder the condition so the control flow is
less convoluted.

After that change, the reproducer does not trigger the WARN_ON_ONCE
anymore.

Suggested-by: Paolo Abeni 
Reported-by: syzbot+07a2e4a1a57118ef7355@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=07a2e4a1a57118ef7355
Fixes: aadb2bb83ff7 ("sock_map: Fix a potential use-after-free in sock_map_close()")
Fixes: 5b4a79ba65a1 ("bpf, sockmap: Don't let sock_map_{close,destroy,unhash} call itself")
Cc: stable@vger.kernel.org
Signed-off-by: Thadeu Lima de Souza Cascardo 
Acked-by: Jakub Sitnicki 
Link: https://lore.kernel.org/r/20240524144702.1178377-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: make the "split" NLM_DONE handling generic

2024-06-21T12:40:06+00:00

[ Upstream commit 5b4b62a169e10401cca34a6e7ac39161986f5605 ]

Jaroslav reports Dell's OMSA Systems Management Data Engine
expects NLM_DONE in a separate recvmsg(), both for rtnl_dump_ifinfo()
and inet_dump_ifaddr(). We already added a similar fix previously in
commit 460b0d33cf10 ("inet: bring NLM_DONE out to a separate recv() again")

Instead of modifying all the dump handlers, and making them look
different than modern for_each_netdev_dump()-based dump handlers -
put the workaround in rtnetlink code. This will also help us move
the custom rtnl-locking from af_netlink in the future (in net-next).

Note that this change is not touching rtnl_dump_all(). rtnl_dump_all()
is different kettle of fish and a potential problem. We now mix families
in a single recvmsg(), but NLM_DONE is not coalesced.

Tested:

  ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_addr.yaml \
           --dump getaddr --json '{"ifa-family": 2}'

  ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \
           --dump getroute --json '{"rtm-family": 2}'

  ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_link.yaml \
           --dump getlink

Fixes: 3e41af90767d ("rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo()")
Fixes: cdb2f80f1c10 ("inet: use xa_array iterator to implement inet_dump_ifaddr()")
Reported-by: Jaroslav Pulchart 
Link: https://lore.kernel.org/all/CAK8fFZ7MKoFSEzMBDAOjoUt+vTZRRQgLDNXEOfdCCXSoXXKE0g@mail.gmail.com
Signed-off-by: Jakub Kicinski 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

inet: introduce dst_rtable() helper

2024-06-12T09:39:55+00:00

[ Upstream commit 05d6d492097c55f2d153fc3fd33cbe78e1e28e0a ]

I added dst_rt6_info() in commit
e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper")

This patch does a similar change for IPv4.

Instead of (struct rtable *)dst casts, we can use :

 #define dst_rtable(_ptr) \
             container_of_const(_ptr, struct rtable, dst)

Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper.

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Reviewed-by: Sabrina Dubroca 
Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Stable-dep-of: 92f1655aa2b2 ("net: fix __dst_negative_advice() race")
Signed-off-by: Sasha Levin

ipv6: introduce dst_rt6_info() helper

2024-06-12T09:39:54+00:00

[ Upstream commit e8dfd42c17faf183415323db1ef0c977be0d6489 ]

Instead of (struct rt6_info *)dst casts, we can use :

 #define dst_rt6_info(_ptr) \
         container_of_const(_ptr, struct rt6_info, dst)

Some places needed missing const qualifiers :

ip6_confirm_neigh(), ipv6_anycast_destination(),
ipv6_unicast_destination(), has_gateway()

v2: added missing parts (David Ahern)

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Stable-dep-of: 92f1655aa2b2 ("net: fix __dst_negative_advice() race")
Signed-off-by: Sasha Levin

net: give more chances to rcu in netdev_wait_allrefs_any()

2024-05-30T07:44:27+00:00

[ Upstream commit cd42ba1c8ac9deb9032add6adf491110e7442040 ]

This came while reviewing commit c4e86b4363ac ("net: add two more
call_rcu_hurry()").

Paolo asked if adding one synchronize_rcu() would help.

While synchronize_rcu() does not help, making sure to call
rcu_barrier() before msleep(wait) is definitely helping
to make sure lazy call_rcu() are completed.

Instead of waiting ~100 seconds in my tests, the ref_tracker
splats occurs one time only, and netdev_wait_allrefs_any()
latency is reduced to the strict minimum.

Ideally we should audit our call_rcu() users to make sure
no refcount (or cascading call_rcu()) is held too long,
because rcu_barrier() is quite expensive.

Fixes: 0e4be9e57e8c ("net: use exponential backoff in netdev_wait_allrefs")
Signed-off-by: Eric Dumazet 
Link: https://lore.kernel.org/all/28bbf698-befb-42f6-b561-851c67f464aa@kernel.org/T/#m76d73ed6b03cd930778ac4d20a777f22a08d6824
Reviewed-by: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: fix out-of-bounds access in ops_init

2024-05-06T11:38:14+00:00

net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.

It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.

Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.

Signed-off-by: Thadeu Lima de Souza Cascardo 
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni

rtnetlink: Correct nested IFLA_VF_VLAN_LIST attribute validation

2024-05-03T22:57:50+00:00

Each attribute inside a nested IFLA_VF_VLAN_LIST is assumed to be a
struct ifla_vf_vlan_info so the size of such attribute needs to be at least
of sizeof(struct ifla_vf_vlan_info) which is 14 bytes.
The current size validation in do_setvfinfo is against NLA_HDRLEN (4 bytes)
which is less than sizeof(struct ifla_vf_vlan_info) so this validation
is not enough and a too small attribute might be cast to a
struct ifla_vf_vlan_info, this might result in an out of bands
read access when accessing the saved (casted) entry in ivvl.

Fixes: 79aab093a0b5 ("net: Update API for VF vlan protocol 802.1ad support")
Signed-off-by: Roded Zats 
Reviewed-by: Donald Hunter 
Link: https://lore.kernel.org/r/20240502155751.75705-1-rzats@paloaltonetworks.com
Signed-off-by: Jakub Kicinski

net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb

2024-05-02T09:02:48+00:00

Commits a602456 ("udp: Add GRO functions to UDP socket") and 57c67ff ("udp:
additional GRO support") introduce incorrect usage of {ip,ipv6}_hdr in the
complete phase of gro. The functions always return skb->network_header,
which in the case of encapsulated packets at the gro complete phase, is
always set to the innermost L3 of the packet. That means that calling
{ip,ipv6}_hdr for skbs which completed the GRO receive phase (both in
gro_list and *_gro_complete) when parsing an encapsulated packet's _outer_
L3/L4 may return an unexpected value.

This incorrect usage leads to a bug in GRO's UDP socket lookup.
udp{4,6}_lib_lookup_skb functions use ip_hdr/ipv6_hdr respectively. These
*_hdr functions return network_header which will point to the innermost L3,
resulting in the wrong offset being used in __udp{4,6}_lib_lookup with
encapsulated packets.

This patch adds network_offset and inner_network_offset to napi_gro_cb, and
makes sure both are set correctly.

To fix the issue, network_offsets union is used inside napi_gro_cb, in
which both the outer and the inner network offsets are saved.

Reproduction example:

Endpoint configuration example (fou + local address bind)

    # ip fou add port 6666 ipproto 4
    # ip link add name tun1 type ipip remote 2.2.2.1 local 2.2.2.2 encap fou encap-dport 5555 encap-sport 6666 mode ipip
    # ip link set tun1 up
    # ip a add 1.1.1.2/24 dev tun1

Netperf TCP_STREAM result on net-next before patch is applied:

net-next main, GRO enabled:
    $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5
    Recv   Send    Send
    Socket Socket  Message  Elapsed
    Size   Size    Size     Time     Throughput
    bytes  bytes   bytes    secs.    10^6bits/sec

    131072  16384  16384    5.28        2.37

net-next main, GRO disabled:
    $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5
    Recv   Send    Send
    Socket Socket  Message  Elapsed
    Size   Size    Size     Time     Throughput
    bytes  bytes   bytes    secs.    10^6bits/sec

    131072  16384  16384    5.01     2745.06

patch applied, GRO enabled:
    $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5
    Recv   Send    Send
    Socket Socket  Message  Elapsed
    Size   Size    Size     Time     Throughput
    bytes  bytes   bytes    secs.    10^6bits/sec

    131072  16384  16384    5.01     2877.38

Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket")
Signed-off-by: Richard Gobert 
Reviewed-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni

net: core: reject skb_copy(_expand) for fraglist GSO skbs

2024-05-01T10:44:10+00:00

SKB_GSO_FRAGLIST skbs must not be linearized, otherwise they become
invalid. Return NULL if such an skb is passed to skb_copy or
skb_copy_expand, in order to prevent a crash on a potential later
call to skb_gso_segment.

Fixes: 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.")
Signed-off-by: Felix Fietkau 
Signed-off-by: David S. Miller

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2024-04-27T00:36:53+00:00

Daniel Borkmann says:

====================
pull-request: bpf 2024-04-26

We've added 12 non-merge commits during the last 22 day(s) which contain
a total of 14 files changed, 168 insertions(+), 72 deletions(-).

The main changes are:

1) Fix BPF_PROBE_MEM in verifier and JIT to skip loads from vsyscall page,
   from Puranjay Mohan.

2) Fix a crash in XDP with devmap broadcast redirect when the latter map
   is in process of being torn down, from Toke Høiland-Jørgensen.

3) Fix arm64 and riscv64 BPF JITs to properly clear start time for BPF
   program runtime stats, from Xu Kuohai.

4) Fix a sockmap KCSAN-reported data race in sk_psock_skb_ingress_enqueue,
    from Jason Xing.

5) Fix BPF verifier error message in resolve_pseudo_ldimm64,
   from Anton Protopopov.

6) Fix missing DEBUG_INFO_BTF_MODULES Kconfig menu item,
   from Andrii Nakryiko.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Test PROBE_MEM of VSYSCALL_ADDR on x86-64
  bpf, x86: Fix PROBE_MEM runtime load check
  bpf: verifier: prevent userspace memory access
  xdp: use flags field to disambiguate broadcast redirect
  arm32, bpf: Reimplement sign-extension mov instruction
  riscv, bpf: Fix incorrect runtime stats
  bpf, arm64: Fix incorrect runtime stats
  bpf: Fix a verifier verbose message
  bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue
  MAINTAINERS: bpf: Add Lehui and Puranjay as riscv64 reviewers
  MAINTAINERS: Update email address for Puranjay Mohan
  bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition
====================

Link: https://lore.kernel.org/r/20240426224248.26197-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski