linux-stable.git/tools/testing/selftests/bpf, branch v6.2.7

Revert "bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES"

2023-03-17T07:58:03+00:00

commit 181127fb76e62d06ab17a75fd610129688612343 upstream.

This reverts commit 6c20822fada1b8adb77fa450d03a0d449686a4a9.

build bot failed on arch with different cache line size:
https://lore.kernel.org/bpf/50c35055-afa9-d01e-9a05-ea5351280e4f@intel.com/

Signed-off-by: Martin KaFai Lau 
Signed-off-by: Greg Kroah-Hartman

bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES

2023-03-17T07:57:56+00:00

[ Upstream commit 6c20822fada1b8adb77fa450d03a0d449686a4a9 ]

&xdp_buff and &xdp_frame are bound in a way that

xdp_buff->data_hard_start == xdp_frame

It's always the case and e.g. xdp_convert_buff_to_frame() relies on
this.
IOW, the following:

	for (u32 i = 0; i < 0xdead; i++) {
		xdpf = xdp_convert_buff_to_frame(&xdp);
		xdp_convert_frame_to_buff(xdpf, &xdp);
	}

shouldn't ever modify @xdpf's contents or the pointer itself.
However, "live packet" code wrongly treats &xdp_frame as part of its
context placed *before* the data_hard_start. With such flow,
data_hard_start is sizeof(*xdpf) off to the right and no longer points
to the XDP frame.

Instead of replacing `sizeof(ctx)` with `offsetof(ctx, xdpf)` in several
places and praying that there are no more miscalcs left somewhere in the
code, unionize ::frm with ::data in a flex array, so that both starts
pointing to the actual data_hard_start and the XDP frame actually starts
being a part of it, i.e. a part of the headroom, not the context.
A nice side effect is that the maximum frame size for this mode gets
increased by 40 bytes, as xdp_buff::frame_sz includes everything from
data_hard_start (-> includes xdpf already) to the end of XDP/skb shared
info.
Also update %MAX_PKT_SIZE accordingly in the selftests code. Leave it
hardcoded for 64 bit && 4k pages, it can be made more flexible later on.

Minor: align `&head->data` with how `head->frm` is assigned for
consistency.
Minor #2: rename 'frm' to 'frame' in &xdp_page_head while at it for
clarity.

(was found while testing XDP traffic generator on ice, which calls
 xdp_convert_frame_to_buff() for each XDP frame)

Fixes: b530e9e1063e ("bpf: Add "live packet" mode for XDP in BPF_PROG_RUN")
Acked-by: Toke Høiland-Jørgensen 
Signed-off-by: Alexander Lobakin 
Link: https://lore.kernel.org/r/20230215185440.4126672-1-aleksander.lobakin@intel.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

selftests/bpf: Fix xdp_do_redirect on s390x

2023-03-10T08:28:22+00:00

[ Upstream commit 06c1865b0b0c7820ea53af2394dd7aff31100295 ]

s390x cache line size is 256 bytes, so skb_shared_info must be aligned
on a much larger boundary than for x86. This makes the maximum packet
size smaller.

Signed-off-by: Ilya Leoshkevich 
Link: https://lore.kernel.org/r/20230128000650.1516334-11-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: 6c20822fada1 ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES")
Signed-off-by: Sasha Levin

selftests/bpf: Fix map_kptr test.

2023-03-10T08:28:22+00:00

[ Upstream commit 62d101d5f422cde39b269f7eb4cbbe2f1e26f9d4 ]

The compiler is optimizing out majority of unref_ptr read/writes, so the test
wasn't testing much. For example, one could delete '__kptr' tag from
'struct prog_test_ref_kfunc __kptr *unref_ptr;' and the test would still "pass".

Convert it to volatile stores. Confirmed by comparing bpf asm before/after.

Fixes: 2cbc469a6fc3 ("selftests/bpf: Add C tests for kptr")
Signed-off-by: Alexei Starovoitov 
Acked-by: Stanislav Fomichev 
Acked-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20230214235051.22938-1-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

selftests/bpf: Fix out-of-srctree build

2023-03-10T08:28:20+00:00

[ Upstream commit 0b0757244754ea1d0721195c824770f5576e119e ]

Building BPF selftests out of srctree fails with:

  make: *** No rule to make target '/linux-build//ima_setup.sh', needed by 'ima_setup.sh'.  Stop.

The culprit is the rule that defines convenient shorthands like
"make test_progs", which builds $(OUTPUT)/test_progs. These shorthands
make sense only for binaries that are built though; scripts that live
in the source tree do not end up in $(OUTPUT).

Therefore drop $(TEST_PROGS) and $(TEST_PROGS_EXTENDED) from the rule.

The issue exists for a while, but it became a problem only after commit
d68ae4982cb7 ("selftests/bpf: Install all required files to run selftests"),
which added dependencies on these scripts.

Fixes: 03dcb78460c2 ("selftests/bpf: Add simple per-test targets to Makefile")
Signed-off-by: Ilya Leoshkevich 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230208231211.283606-1-iii@linux.ibm.com
Signed-off-by: Sasha Levin

selftests/bpf: Initialize tc in xdp_synproxy

2023-03-10T08:28:12+00:00

[ Upstream commit 354bb4a0e0b6be8f55bacbe7f08c94b4741f5658 ]

xdp_synproxy/xdp fails in CI with:

    Error: bpf_tc_hook_create: File exists

The XDP version of the test should not be calling bpf_tc_hook_create();
the reason it's happening anyway is that if we don't specify --tc on the
command line, tc variable remains uninitialized.

Fixes: 784d5dc0efc2 ("selftests/bpf: Add selftests for raw syncookie helpers in TC mode")
Reported-by: Alexei Starovoitov 
Reported-by: Joanne Koong 
Signed-off-by: Ilya Leoshkevich 
Link: https://lore.kernel.org/r/20230202235335.3403781-1-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: Fix vmtest static compilation error

2023-03-10T08:28:11+00:00

[ Upstream commit 2514a31241e1e9067d379e0fbdb60e4bc2bf4659 ]

As stated in README.rst, in order to resolve errors with linker errors,
'LDLIBS=-static' should be used. Most problems will be solved by this
option, but in the case of urandom_read, this won't fix the problem. So
the Makefile is currently implemented to strip the 'static' option when
compiling the urandom_read. However, stripping this static option isn't
configured properly on $(LDLIBS) correctly, which is now causing errors
on static compilation.

    # LDLIBS=-static ./vmtest.sh
    ld.lld: error: attempted static link of dynamic object liburandom_read.so
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    make: *** [Makefile:190: /linux/tools/testing/selftests/bpf/urandom_read] Error 1
    make: *** Waiting for unfinished jobs....

This commit fixes this problem by configuring the strip with $(LDLIBS).

Fixes: 68084a136420 ("selftests/bpf: Fix building bpf selftests statically")
Signed-off-by: Daniel T. Lee 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230125100440.21734-1-danieltimlee@gmail.com
Signed-off-by: Sasha Levin

bpf: Fix partial dynptr stack slot reads/writes

2023-03-10T08:28:10+00:00

[ Upstream commit ef8fc7a07c0e161841779d6fe3f6acd5a05c547c ]

Currently, while reads are disallowed for dynptr stack slots, writes are
not. Reads don't work from both direct access and helpers, while writes
do work in both cases, but have the effect of overwriting the slot_type.

While this is fine, handling for a few edge cases is missing. Firstly,
a user can overwrite the stack slots of dynptr partially.

Consider the following layout:
spi: [d][d][?]
      2  1  0

First slot is at spi 2, second at spi 1.
Now, do a write of 1 to 8 bytes for spi 1.

This will essentially either write STACK_MISC for all slot_types or
STACK_MISC and STACK_ZERO (in case of size < BPF_REG_SIZE partial write
of zeroes). The end result is that slot is scrubbed.

Now, the layout is:
spi: [d][m][?]
      2  1  0

Suppose if user initializes spi = 1 as dynptr.
We get:
spi: [d][d][d]
      2  1  0

But this time, both spi 2 and spi 1 have first_slot = true.

Now, when passing spi 2 to dynptr helper, it will consider it as
initialized as it does not check whether second slot has first_slot ==
false. And spi 1 should already work as normal.

This effectively replaced size + offset of first dynptr, hence allowing
invalid OOB reads and writes.

Make a few changes to protect against this:
When writing to PTR_TO_STACK using BPF insns, when we touch spi of a
STACK_DYNPTR type, mark both first and second slot (regardless of which
slot we touch) as STACK_INVALID. Reads are already prevented.

Second, prevent writing	to stack memory from helpers if the range may
contain any STACK_DYNPTR slots. Reads are already prevented.

For helpers, we cannot allow it to destroy dynptrs from the writes as
depending on arguments, helper may take uninit_mem and dynptr both at
the same time. This would mean that helper may write to uninit_mem
before it reads the dynptr, which would be bad.

PTR_TO_MEM: [?????dd]

Depending on the code inside the helper, it may end up overwriting the
dynptr contents first and then read those as the dynptr argument.

Verifier would only simulate destruction when it does byte by byte
access simulation in check_helper_call for meta.access_size, and
fail to catch this case, as it happens after argument checks.

The same would need to be done for any other non-trivial objects created
on the stack in the future, such as bpf_list_head on stack, or
bpf_rb_root on stack.

A common misunderstanding in the current code is that MEM_UNINIT means
writes, but note that writes may also be performed even without
MEM_UNINIT in case of helpers, in that case the code after handling meta
&& meta->raw_mode will complain when it sees STACK_DYNPTR. So that
invalid read case also covers writes to potential STACK_DYNPTR slots.
The only loophole was in case of meta->raw_mode which simulated writes
through instructions which could overwrite them.

A future series sequenced after this will focus on the clean up of
helper access checks and bugs around that.

Fixes: 97e03f521050 ("bpf: Add verifier support for dynptrs")
Signed-off-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20230121002241.2113993-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

bpf: Fix missing var_off check for ARG_PTR_TO_DYNPTR

2023-03-10T08:28:10+00:00

[ Upstream commit 79168a669d8125453c8a271115f1ffd4294e61f6 ]

Currently, the dynptr function is not checking the variable offset part
of PTR_TO_STACK that it needs to check. The fixed offset is considered
when computing the stack pointer index, but if the variable offset was
not a constant (such that it could not be accumulated in reg->off), we
will end up a discrepency where runtime pointer does not point to the
actual stack slot we mark as STACK_DYNPTR.

It is impossible to precisely track dynptr state when variable offset is
not constant, hence, just like bpf_timer, kptr, bpf_spin_lock, etc.
simply reject the case where reg->var_off is not constant. Then,
consider both reg->off and reg->var_off.value when computing the stack
pointer index.

A new helper dynptr_get_spi is introduced to hide over these details
since the dynptr needs to be located in multiple places outside the
process_dynptr_func checks, hence once we know it's a PTR_TO_STACK, we
need to enforce these checks in all places.

Note that it is disallowed for unprivileged users to have a non-constant
var_off, so this problem should only be possible to trigger from
programs having CAP_PERFMON. However, its effects can vary.

Without the fix, it is possible to replace the contents of the dynptr
arbitrarily by making verifier mark different stack slots than actual
location and then doing writes to the actual stack address of dynptr at
runtime.

Fixes: 97e03f521050 ("bpf: Add verifier support for dynptrs")
Acked-by: Joanne Koong 
Signed-off-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20230121002241.2113993-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: Fix build errors if CONFIG_NF_CONNTRACK=m

2023-03-10T08:28:09+00:00

[ Upstream commit 92afc5329a5b23d876b215b783d200352d5aaea6 ]

If CONFIG_NF_CONNTRACK=m, there are no definitions of NF_NAT_MANIP_SRC
and NF_NAT_MANIP_DST in vmlinux.h, build test_bpf_nf.c failed.

$ make -C tools/testing/selftests/bpf/

  CLNG-BPF [test_maps] test_bpf_nf.bpf.o
progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
                bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
                                                       ^
progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
                bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
                                                       ^
2 errors generated.

Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c,
in order to avoid redefinitions if CONFIG_NF_CONNTRACK=y, rename them with
___local suffix. This is similar with commit 1058b6a78db2 ("selftests/bpf:
Do not fail build if CONFIG_NF_CONNTRACK=m/n").

Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
Signed-off-by: Tiezhu Yang 
Acked-by: Jiri Olsa 
Tested-by: Jiri Olsa 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/r/1674028604-7113-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin