linux-stable.git/include/uapi, branch v5.15.151

bpf: Derive source IP addr via bpf_*_fib_lookup()

2024-03-06T14:38:50+00:00

commit dab4e1f06cabb6834de14264394ccab197007302 upstream.

Extend the bpf_fib_lookup() helper by making it to return the source
IPv4/IPv6 address if the BPF_FIB_LOOKUP_SRC flag is set.

For example, the following snippet can be used to derive the desired
source IP address:

    struct bpf_fib_lookup p = { .ipv4_dst = ip4->daddr };

    ret = bpf_skb_fib_lookup(skb, p, sizeof(p),
            BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH);
    if (ret != BPF_FIB_LKUP_RET_SUCCESS)
        return TC_ACT_SHOT;

    /* the p.ipv4_src now contains the source address */

The inability to derive the proper source address may cause malfunctions
in BPF-based dataplanes for hosts containing netdevs with more than one
routable IP address or for multi-homed hosts.

For example, Cilium implements packet masquerading in BPF. If an
egressing netdev to which the Cilium's BPF prog is attached has
multiple IP addresses, then only one [hardcoded] IP address can be used for
masquerading. This breaks connectivity if any other IP address should have
been selected instead, for example, when a public and private addresses
are attached to the same egress interface.

The change was tested with Cilium [1].

Nikolay Aleksandrov helped to figure out the IPv6 addr selection.

[1]: https://github.com/cilium/cilium/pull/28283

Signed-off-by: Martynas Pumputis 
Link: https://lore.kernel.org/r/20231007081415.33502-2-m@lambda.lt
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Greg Kroah-Hartman

bpf: Add table ID to bpf_fib_lookup BPF helper

2024-03-06T14:38:50+00:00

commit 8ad77e72caae22a1ddcfd0c03f2884929e93b7a4 upstream.

Add ability to specify routing table ID to the `bpf_fib_lookup` BPF
helper.

A new field `tbid` is added to `struct bpf_fib_lookup` used as
parameters to the `bpf_fib_lookup` BPF helper.

When the helper is called with the `BPF_FIB_LOOKUP_DIRECT` and
`BPF_FIB_LOOKUP_TBID` flags the `tbid` field in `struct bpf_fib_lookup`
will be used as the table ID for the fib lookup.

If the `tbid` does not exist the fib lookup will fail with
`BPF_FIB_LKUP_RET_NOT_FWDED`.

The `tbid` field becomes a union over the vlan related output fields
in `struct bpf_fib_lookup` and will be zeroed immediately after usage.

This functionality is useful in containerized environments.

For instance, if a CNI wants to dictate the next-hop for traffic leaving
a container it can create a container-specific routing table and perform
a fib lookup against this table in a "host-net-namespace-side" TC program.

This functionality also allows `ip rule` like functionality at the TC
layer, allowing an eBPF program to pick a routing table based on some
aspect of the sk_buff.

As a concrete use case, this feature will be used in Cilium's SRv6 L3VPN
datapath.

When egress traffic leaves a Pod an eBPF program attached by Cilium will
determine which VRF the egress traffic should target, and then perform a
FIB lookup in a specific table representing this VRF's FIB.

Signed-off-by: Louis DeLosSantos 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230505-bpf-add-tbid-fib-lookup-v2-1-0a31c22c748c@gmail.com
Signed-off-by: Greg Kroah-Hartman

bpf: Add BPF_FIB_LOOKUP_SKIP_NEIGH for bpf_fib_lookup

2024-03-06T14:38:50+00:00

commit 31de4105f00d64570139bc5494a201b0bd57349f upstream.

The bpf_fib_lookup() also looks up the neigh table.
This was done before bpf_redirect_neigh() was added.

In the use case that does not manage the neigh table
and requires bpf_fib_lookup() to lookup a fib to
decide if it needs to redirect or not, the bpf prog can
depend only on using bpf_redirect_neigh() to lookup the
neigh. It also keeps the neigh entries fresh and connected.

This patch adds a bpf_fib_lookup flag, SKIP_NEIGH, to avoid
the double neigh lookup when the bpf prog always call
bpf_redirect_neigh() to do the neigh lookup. The params->smac
output is skipped together when SKIP_NEIGH is set because
bpf_redirect_neigh() will figure out the smac also.

Signed-off-by: Martin KaFai Lau 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230217205515.3583372-1-martin.lau@linux.dev
Signed-off-by: Greg Kroah-Hartman

uapi: in6: replace temporary label with rfc9486

2024-03-06T14:38:45+00:00

[ Upstream commit 6a2008641920a9c6fe1abbeb9acbec463215d505 ]

Not really a fix per se, but IPV6_TLV_IOAM is still tagged as "TEMPORARY
IANA allocation for IOAM", while RFC 9486 is available for some time
now. Just update the reference.

Fixes: 9ee11f0fff20 ("ipv6: ioam: Data plane support for Pre-allocated Trace")
Signed-off-by: Justin Iurman 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20240226124921.9097-1-justin.iurman@uliege.be
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

netfilter: nft_compat: reject unused compat flag

2024-02-23T07:54:58+00:00

[ Upstream commit 292781c3c5485ce33bd22b2ef1b2bed709b4d672 ]

Flag (1 << 0) is ignored is set, never used, reject it it with EINVAL
instead.

Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

btrfs: add definition for EXTENT_TREE_V2

2024-02-23T07:54:34+00:00

[ Upstream commit 2c7d2a230237e7c43fa067d695937b7e484bb92a ]

This adds the initial definition of the EXTENT_TREE_V2 incompat feature
flag.  This also hides the support behind CONFIG_BTRFS_DEBUG.

THIS IS A IN DEVELOPMENT FORMAT CHANGE, DO NOT USE UNLESS YOU ARE A
DEVELOPER OR A TESTER.

The format is in flux and will be added in stages, any fs will need to
be re-made between updates to the format.

Signed-off-by: Josef Bacik 
Signed-off-by: David Sterba 
Stable-dep-of: 7081929ab257 ("btrfs: don't abort filesystem when attempting to snapshot deleted subvolume")
Signed-off-by: Sasha Levin

btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_args

2024-02-23T07:54:31+00:00

commit 173431b274a9a54fc10b273b46e67f46bcf62d2e upstream.

Add extra sanity check for btrfs_ioctl_defrag_range_args::flags.

This is not really to enhance fuzzing tests, but as a preparation for
future expansion on btrfs_ioctl_defrag_range_args.

In the future we're going to add new members, allowing more fine tuning
for btrfs defrag.  Without the -ENONOTSUPP error, there would be no way
to detect if the kernel supports those new defrag features.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana 
Signed-off-by: Qu Wenruo 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

bpf: Add crosstask check to __bpf_get_stack

2024-01-25T22:52:36+00:00

[ Upstream commit b8e3a87a627b575896e448021e5c2f8a3bc19931 ]

Currently get_perf_callchain only supports user stack walking for
the current task. Passing the correct *crosstask* param will return
0 frames if the task passed to __bpf_get_stack isn't the current
one instead of a single incorrect frame/address. This change
passes the correct *crosstask* param but also does a preemptive
check in __bpf_get_stack if the task is current and returns
-EOPNOTSUPP if it is not.

This issue was found using bpf_get_task_stack inside a BPF
iterator ("iter/task"), which iterates over all tasks.
bpf_get_task_stack works fine for fetching kernel stacks
but because get_perf_callchain relies on the caller to know
if the requested *task* is the current one (via *crosstask*)
it was failing in a confusing way.

It might be possible to get user stacks for all tasks utilizing
something like access_process_vm but that requires the bpf
program calling bpf_get_task_stack to be sleepable and would
therefore be a breaking change.

Fixes: fa28dcb82a38 ("bpf: Introduce helper bpf_get_task_stack()")
Signed-off-by: Jordan Rome 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20231108112334.3433136-1-jordalgo@meta.com
Signed-off-by: Sasha Levin

perf/core: Add a new read format to get a number of lost samples

2023-12-13T17:36:47+00:00

[ Upstream commit 119a784c81270eb88e573174ed2209225d646656 ]

Sometimes we want to know an accurate number of samples even if it's
lost.  Currenlty PERF_RECORD_LOST is generated for a ring-buffer which
might be shared with other events.  So it's hard to know per-event
lost count.

Add event->lost_samples field and PERF_FORMAT_LOST to retrieve it from
userspace.

Original-patch-by: Jiri Olsa 
Signed-off-by: Namhyung Kim 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20220616180623.1358843-1-namhyung@kernel.org
Stable-dep-of: 382c27f4ed28 ("perf: Fix perf_event_validate_size()")
Signed-off-by: Sasha Levin

uapi: propagate __struct_group() attributes to the container union

2023-12-08T07:48:03+00:00

[ Upstream commit 4e86f32a13af1970d21be94f659cae56bbe487ee ]

Recently the kernel test robot has reported an ARM-specific BUILD_BUG_ON()
in an old and unmaintained wil6210 wireless driver. The problem comes from
the structure packing rules of old ARM ABI ('-mabi=apcs-gnu'). For example,
the following structure is packed to 18 bytes instead of 16:

struct poorly_packed {
        unsigned int a;
        unsigned int b;
        unsigned short c;
        union {
                struct {
                        unsigned short d;
                        unsigned int e;
                } __attribute__((packed));
                struct {
                        unsigned short d;
                        unsigned int e;
                } __attribute__((packed)) inner;
        };
} __attribute__((packed));

To fit it into 16 bytes, it's required to add packed attribute to the
container union as well:

struct poorly_packed {
        unsigned int a;
        unsigned int b;
        unsigned short c;
        union {
                struct {
                        unsigned short d;
                        unsigned int e;
                } __attribute__((packed));
                struct {
                        unsigned short d;
                        unsigned int e;
                } __attribute__((packed)) inner;
        } __attribute__((packed));
} __attribute__((packed));

Thanks to Andrew Pinski of GCC team for sorting the things out at
https://gcc.gnu.org/pipermail/gcc/2023-November/242888.html.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202311150821.cI4yciFE-lkp@intel.com
Signed-off-by: Dmitry Antipov 
Link: https://lore.kernel.org/r/20231120110607.98956-1-dmantipov@yandex.ru
Fixes: 50d7bd38c3aa ("stddef: Introduce struct_group() helper macro")
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin