linux.git/tools/include, branch v6.6.45

bpf: Pack struct bpf_fib_lookup

2024-06-12T09:11:38+00:00

[ Upstream commit f91717007217d975aa975ddabd91ae1a107b9bff ]

The struct bpf_fib_lookup is supposed to be of size 64. A recent commit
59b418c7063d ("bpf: Add a check for struct bpf_fib_lookup size") added
a static assertion to check this property so that future changes to the
structure will not accidentally break this assumption.

As it immediately turned out, on some 32-bit arm systems, when AEABI=n,
the total size of the structure was equal to 68, see [1]. This happened
because the bpf_fib_lookup structure contains a union of two 16-bit
fields:

    union {
            __u16 tot_len;
            __u16 mtu_result;
    };

which was supposed to compile to a 16-bit-aligned 16-bit field. On the
aforementioned setups it was instead both aligned and padded to 32-bits.

Declare this inner union as __attribute__((packed, aligned(2))) such
that it always is of size 2 and is aligned to 16 bits.

  [1] https://lore.kernel.org/all/CA+G9fYtsoP51f-oP_Sp5MOq-Ffv8La2RztNpwvE6+R1VtFiLrw@mail.gmail.com/#t

Reported-by: Naresh Kamboju 
Fixes: e1850ea9bd9e ("bpf: bpf_fib_lookup return MTU value as output when looked up")
Signed-off-by: Anton Protopopov 
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Alexander Lobakin 
Acked-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20240403123303.1452184-1-aspsk@isovalent.com
Signed-off-by: Sasha Levin

tools/nolibc/stdlib: fix memory error in realloc()

2024-06-12T09:11:19+00:00

commit 791f4641142e2aced85de082e5783b4fb0b977c2 upstream.

Pass user_p_len to memcpy() instead of heap->len to prevent realloc()
from copying an extra sizeof(heap) bytes from beyond the allocated
region.

Signed-off-by: Brennan Xavier McManus 
Cc: stable@vger.kernel.org
Reviewed-by: Ammar Faizi 
Fixes: 0e0ff638400be8f497a35b51a4751fd823f6bd6a ("tools/nolibc/stdlib: Implement `malloc()`, `calloc()`, `realloc()` and `free()`")
Signed-off-by: Willy Tarreau 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Greg Kroah-Hartman

memblock tests: fix undefined reference to `panic'

2024-05-17T10:02:14+00:00

[ Upstream commit e0f5a8e74be88f2476e58b25d3b49a9521bdc4ec ]

commit e96c6b8f212a ("memblock: report failures when memblock_can_resize
is not set") introduced the usage of panic, which is not defined in
memblock test.

Let's define it directly in panic.h to fix it.

Signed-off-by: Wei Yang 
CC: Song Shuai 
CC: Mike Rapoport 
Link: https://lore.kernel.org/r/20240402132701.29744-3-richard.weiyang@gmail.com
Signed-off-by: Mike Rapoport (IBM) 
Signed-off-by: Sasha Levin

memblock tests: fix undefined reference to `early_pfn_to_nid'

2024-05-17T10:02:14+00:00

[ Upstream commit 7d8ed162e6a92268d4b2b84d364a931216102c8e ]

commit 6a9531c3a880 ("memblock: fix crash when reserved memory is not
added to memory") introduce the usage of early_pfn_to_nid, which is not
defined in memblock tests.

The original definition of early_pfn_to_nid is defined in mm.h, so let
add this in the corresponding mm.h.

Signed-off-by: Wei Yang 
CC: Yajun Deng 
CC: Mike Rapoport 
Link: https://lore.kernel.org/r/20240402132701.29744-2-richard.weiyang@gmail.com
Signed-off-by: Mike Rapoport (IBM) 
Signed-off-by: Sasha Levin

tools/resolve_btfids: fix build with musl libc

2024-04-03T13:29:03+00:00

commit 62248b22d01e96a4d669cde0d7005bd51ebf9e76 upstream.

Include the header that defines u32.
This fixes build of 6.6.23 and 6.1.83 kernels for Alpine Linux, which
uses musl libc. I assume that GNU libc indirecly pulls in linux/types.h.

Fixes: 9707ac4fe2f5 ("tools/resolve_btfids: Refactor set sorting with types from btf_ids.h")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218647
Cc: stable@vger.kernel.org
Signed-off-by: Natanael Copa 
Tested-by: Greg Thelen 
Link: https://lore.kernel.org/r/20240328110103.28734-1-ncopa@alpinelinux.org
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Greg Kroah-Hartman

tools/resolve_btfids: Refactor set sorting with types from btf_ids.h

2024-03-26T22:19:27+00:00

[ Upstream commit 9707ac4fe2f5bac6406d2403f8b8a64d7b3d8e43 ]

Instead of using magic offsets to access BTF ID set data, leverage types
from btf_ids.h (btf_id_set and btf_id_set8) which define the actual
layout of the data. Thanks to this change, set sorting should also
continue working if the layout changes.

This requires to sync the definition of 'struct btf_id_set8' from
include/linux/btf_ids.h to tools/include/linux/btf_ids.h. We don't sync
the rest of the file at the moment, b/c that would require to also sync
multiple dependent headers and we don't need any other defs from
btf_ids.h.

Signed-off-by: Viktor Malik 
Signed-off-by: Andrii Nakryiko 
Acked-by: Daniel Xu 
Link: https://lore.kernel.org/bpf/ff7f062ddf6a00815fda3087957c4ce667f50532.1707223196.git.vmalik@redhat.com
Stable-dep-of: 903fad439466 ("tools/resolve_btfids: Fix cross-compilation to non-host endianness")
Signed-off-by: Sasha Levin

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

2024-03-01T12:35:04+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 
Cc: Daniel Borkmann 
Signed-off-by: Greg Kroah-Hartman

work around gcc bugs with 'asm goto' with outputs

2024-02-23T08:24:47+00:00

commit 4356e9f841f7fbb945521cef3577ba394c65f3fc upstream.

We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c3238a ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f53 ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").

Then, much later, we ended up removing the workaround in commit
43c249ea0b1e ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.

Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround.  But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.

It looks like there are at least two separate issues that all hit in
this area:

 (a) some versions of gcc don't mark the asm goto as 'volatile' when it
     has outputs:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420

     which is easy to work around by just adding the 'volatile' by hand.

 (b) Internal compiler errors:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422

     which are worked around by adding the extra empty 'asm' as a
     barrier, as in the original workaround.

but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.

but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.

Reported-and-tested-by: Sean Christopherson 
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers 
Cc: Uros Bizjak 
Cc: Jakub Jelinek 
Cc: Andrew Pinski 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

bpf: Add crosstask check to __bpf_get_stack

2024-01-25T23:35:19+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

mm: add a NO_INHERIT flag to the PR_SET_MDWE prctl

2023-12-03T06:33:06+00:00

[ Upstream commit 24e41bf8a6b424c76c5902fb999e9eca61bdf83d ]

This extends the current PR_SET_MDWE prctl arg with a bit to indicate that
the process doesn't want MDWE protection to propagate to children.

To implement this no-inherit mode, the tag in current->mm->flags must be
absent from MMF_INIT_MASK.  This means that the encoding for "MDWE but
without inherit" is different in the prctl than in the mm flags.  This
leads to a bit of bit-mangling in the prctl implementation.

Link: https://lkml.kernel.org/r/20230828150858.393570-6-revest@chromium.org
Signed-off-by: Florent Revest 
Reviewed-by: Kees Cook 
Reviewed-by: Catalin Marinas 
Cc: Alexey Izbyshev 
Cc: Anshuman Khandual 
Cc: Ayush Jain 
Cc: David Hildenbrand 
Cc: Greg Thelen 
Cc: Joey Gouly 
Cc: KP Singh 
Cc: Mark Brown 
Cc: Michal Hocko 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Szabolcs Nagy 
Cc: Topi Miettinen 
Signed-off-by: Andrew Morton 
Stable-dep-of: 793838138c15 ("prctl: Disable prctl(PR_SET_MDWE) on parisc")
Signed-off-by: Sasha Levin