linux-stable.git/net/socket.c, branch v6.6.71

net: explicitly clear the sk pointer, when pf->create fails

2024-10-17T13:24:35+00:00

commit 631083143315d1b192bd7d915b967b37819e88ea upstream.

We have recently noticed the exact same KASAN splat as in commit
6cd4a78d962b ("net: do not leave a dangling sk pointer, when socket
creation fails"). The problem is that commit did not fully address the
problem, as some pf->create implementations do not use sk_common_release
in their error paths.

For example, we can use the same reproducer as in the above commit, but
changing ping to arping. arping uses AF_PACKET socket and if packet_create
fails, it will just sk_free the allocated sk object.

While we could chase all the pf->create implementations and make sure they
NULL the freed sk object on error from the socket, we can't guarantee
future protocols will not make the same mistake.

So it is easier to just explicitly NULL the sk pointer upon return from
pf->create in __sock_create. We do know that pf->create always releases the
allocated sk object on error, so if the pointer is not NULL, it is
definitely dangling.

Fixes: 6cd4a78d962b ("net: do not leave a dangling sk pointer, when socket creation fails")
Signed-off-by: Ignat Korchagin 
Cc: stable@vger.kernel.org
Reviewed-by: Eric Dumazet 
Link: https://patch.msgid.link/20241003170151.69445-1-ignat@cloudflare.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

bpf, net: Fix a potential race in do_sock_getsockopt()

2024-09-12T09:11:34+00:00

[ Upstream commit 33f339a1ba54e56bba57ee9a77c71e385ab4825c ]

There's a potential race when `cgroup_bpf_enabled(CGROUP_GETSOCKOPT)` is
false during the execution of `BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN`, but
becomes true when `BPF_CGROUP_RUN_PROG_GETSOCKOPT` is called.
This inconsistency can lead to `BPF_CGROUP_RUN_PROG_GETSOCKOPT` receiving
an "-EFAULT" from `__cgroup_bpf_run_filter_getsockopt(max_optlen=0)`.
Scenario shown as below:

           `process A`                      `process B`
           -----------                      ------------
  BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN
                                            enable CGROUP_GETSOCKOPT
  BPF_CGROUP_RUN_PROG_GETSOCKOPT (-EFAULT)

To resolve this, remove the `BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN` macro and
directly uses `copy_from_sockptr` to ensure that `max_optlen` is always
set before `BPF_CGROUP_RUN_PROG_GETSOCKOPT` is invoked.

Fixes: 0d01da6afc54 ("bpf: implement getsockopt and setsockopt hooks")
Co-developed-by: Yanghui Li 
Signed-off-by: Yanghui Li 
Co-developed-by: Cheng-Jui Wang 
Signed-off-by: Cheng-Jui Wang 
Signed-off-by: Tze-nan Wu 
Acked-by: Stanislav Fomichev 
Acked-by: Alexei Starovoitov 
Link: https://patch.msgid.link/20240830082518.23243-1-Tze-nan.Wu@mediatek.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net/socket: Break down __sys_getsockopt

2024-09-12T09:11:34+00:00

[ Upstream commit 0b05b0cd78c92371fdde6333d006f39eaf9e0860 ]

Split __sys_getsockopt() into two functions by removing the core
logic into a sub-function (do_sock_getsockopt()). This will avoid
code duplication when doing the same operation in other callers, for
instance.

do_sock_getsockopt() will be called by io_uring getsockopt() command
operation in the following patch.

The same was done for the setsockopt pair.

Suggested-by: Martin KaFai Lau 
Signed-off-by: Breno Leitao 
Acked-by: Jakub Kicinski 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/r/20231016134750.1381153-5-leitao@debian.org
Signed-off-by: Jens Axboe 
Stable-dep-of: 33f339a1ba54 ("bpf, net: Fix a potential race in do_sock_getsockopt()")
Signed-off-by: Sasha Levin

net/socket: Break down __sys_setsockopt

2024-09-12T09:11:34+00:00

[ Upstream commit 1406245c29454ff84919736be83e14cdaba7fec1 ]

Split __sys_setsockopt() into two functions by removing the core
logic into a sub-function (do_sock_setsockopt()). This will avoid
code duplication when doing the same operation in other callers, for
instance.

do_sock_setsockopt() will be called by io_uring setsockopt() command
operation in the following patch.

Signed-off-by: Breno Leitao 
Reviewed-by: Willem de Bruijn 
Acked-by: Jakub Kicinski 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/r/20231016134750.1381153-4-leitao@debian.org
Signed-off-by: Jens Axboe 
Stable-dep-of: 33f339a1ba54 ("bpf, net: Fix a potential race in do_sock_getsockopt()")
Signed-off-by: Sasha Levin

bpf: Add sockptr support for setsockopt

2024-09-12T09:11:34+00:00

[ Upstream commit 3f31e0d14d44ad491a81b7c1f83f32fbc300a867 ]

The whole network stack uses sockptr, and while it doesn't move to
something more modern, let's use sockptr in setsockptr BPF hooks, so, it
could be used by other callers.

The main motivation for this change is to use it in the io_uring
{g,s}etsockopt(), which will use a userspace pointer for *optval, but, a
kernel value for optlen.

Link: https://lore.kernel.org/all/ZSArfLaaGcfd8LH8@gmail.com/

Signed-off-by: Breno Leitao 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/r/20231016134750.1381153-3-leitao@debian.org
Signed-off-by: Jens Axboe 
Stable-dep-of: 33f339a1ba54 ("bpf, net: Fix a potential race in do_sock_getsockopt()")
Signed-off-by: Sasha Levin

bpf: Add sockptr support for getsockopt

2024-09-12T09:11:34+00:00

[ Upstream commit a615f67e1a426f35366b8398c11f31c148e7df48 ]

The whole network stack uses sockptr, and while it doesn't move to
something more modern, let's use sockptr in getsockptr BPF hooks, so, it
could be used by other callers.

The main motivation for this change is to use it in the io_uring
{g,s}etsockopt(), which will use a userspace pointer for *optval, but, a
kernel value for optlen.

Link: https://lore.kernel.org/all/ZSArfLaaGcfd8LH8@gmail.com/

Signed-off-by: Breno Leitao 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/r/20231016134750.1381153-2-leitao@debian.org
Signed-off-by: Jens Axboe 
Stable-dep-of: 33f339a1ba54 ("bpf, net: Fix a potential race in do_sock_getsockopt()")
Signed-off-by: Sasha Levin

net: Save and restore msg_namelen in sock_sendmsg

2024-01-10T16:16:51+00:00

[ Upstream commit 01b2885d9415152bcb12ff1f7788f500a74ea0ed ]

Commit 86a7e0b69bd5 ("net: prevent rewrite of msg_name in
sock_sendmsg()") made sock_sendmsg save the incoming msg_name pointer
and restore it before returning, to insulate the caller against
msg_name being changed by the called code.  If the address length
was also changed however, we may return with an inconsistent structure
where the length doesn't match the address, and attempts to reuse it may
lead to lost packets.

For example, a kernel that doesn't have commit 1c5950fc6fe9 ("udp6: fix
potential access to stale information") will replace a v4 mapped address
with its ipv4 equivalent, and shorten namelen accordingly from 28 to 16.
If the caller attempts to reuse the resulting msg structure, it will have
the original ipv6 (v4 mapped) address but an incorrect v4 length.

Fixes: 86a7e0b69bd5 ("net: prevent rewrite of msg_name in sock_sendmsg()")
Signed-off-by: Marc Dionne 
Reviewed-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: prevent address rewrite in kernel_bind()

2023-10-01T18:31:29+00:00

Similar to the change in commit 0bdf399342c5("net: Avoid address
overwrite in kernel_connect"), BPF hooks run on bind may rewrite the
address passed to kernel_bind(). This change

1) Makes a copy of the bind address in kernel_bind() to insulate
   callers.
2) Replaces direct calls to sock->ops->bind() in net with kernel_bind()

Link: https://lore.kernel.org/netdev/20230912013332.2048422-1-jrife@google.com/
Fixes: 4fbac77d2d09 ("bpf: Hooks for sys_bind")
Cc: stable@vger.kernel.org
Reviewed-by: Willem de Bruijn 
Signed-off-by: Jordan Rife 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller

net: prevent rewrite of msg_name in sock_sendmsg()

2023-10-01T18:31:29+00:00

Callers of sock_sendmsg(), and similarly kernel_sendmsg(), in kernel
space may observe their value of msg_name change in cases where BPF
sendmsg hooks rewrite the send address. This has been confirmed to break
NFS mounts running in UDP mode and has the potential to break other
systems.

This patch:

1) Creates a new function called __sock_sendmsg() with same logic as the
   old sock_sendmsg() function.
2) Replaces calls to sock_sendmsg() made by __sys_sendto() and
   __sys_sendmsg() with __sock_sendmsg() to avoid an unnecessary copy,
   as these system calls are already protected.
3) Modifies sock_sendmsg() so that it makes a copy of msg_name if
   present before passing it down the stack to insulate callers from
   changes to the send address.

Link: https://lore.kernel.org/netdev/20230912013332.2048422-1-jrife@google.com/
Fixes: 1cedee13d25a ("bpf: Hooks for sys_sendmsg")
Cc: stable@vger.kernel.org
Reviewed-by: Willem de Bruijn 
Signed-off-by: Jordan Rife 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller

Merge tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2023-09-08T01:33:07+00:00

Pull networking updates from Jakub Kicinski:
 "Including fixes from netfilter and bpf.

  Current release - regressions:

   - eth: stmmac: fix failure to probe without MAC interface specified

  Current release - new code bugs:

   - docs: netlink: fix missing classic_netlink doc reference

  Previous releases - regressions:

   - deal with integer overflows in kmalloc_reserve()

   - use sk_forward_alloc_get() in sk_get_meminfo()

   - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc

   - fib: avoid warn splat in flow dissector after packet mangling

   - skb_segment: call zero copy functions before using skbuff frags

   - eth: sfc: check for zero length in EF10 RX prefix

  Previous releases - always broken:

   - af_unix: fix msg_controllen test in scm_pidfd_recv() for
     MSG_CMSG_COMPAT

   - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()

   - netfilter:
      - nft_exthdr: fix non-linear header modification
      - xt_u32, xt_sctp: validate user space input
      - nftables: exthdr: fix 4-byte stack OOB write
      - nfnetlink_osf: avoid OOB read
      - one more fix for the garbage collection work from last release

   - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU

   - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t

   - handshake: fix null-deref in handshake_nl_done_doit()

   - ip: ignore dst hint for multipath routes to ensure packets are
     hashed across the nexthops

   - phy: micrel:
      - correct bit assignments for cable test errata
      - disable EEE according to the KSZ9477 errata

  Misc:

   - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations

   - Revert "net: macsec: preserve ingress frame ordering", it appears
     to have been developed against an older kernel, problem doesn't
     exist upstream"

* tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
  net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs()
  Revert "net: team: do not use dynamic lockdep key"
  net: hns3: remove GSO partial feature bit
  net: hns3: fix the port information display when sfp is absent
  net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue
  net: hns3: fix debugfs concurrency issue between kfree buffer and read
  net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read()
  net: hns3: Support query tx timeout threshold by debugfs
  net: hns3: fix tx timeout issue
  net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)
  netfilter: nf_tables: Unbreak audit log reset
  netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
  netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
  netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID
  netfilter: nfnetlink_osf: avoid OOB read
  netfilter: nftables: exthdr: fix 4-byte stack OOB write
  selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
  bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
  bpf: bpf_sk_storage: Fix invalid wait context lockdep report
  s390/bpf: Pass through tail call counter in trampolines
  ...