test_bpf: Rename second ALU64_SMOD_X to ALU64_SMOD_K

Currently, there are two test cases with same name
"ALU64_SMOD_X: -7 % 2 = -1", the first one is right,
the second one should be ALU64_SMOD_K bec

test_bpf: Rename second ALU64_SMOD_X to ALU64_SMOD_K

Currently, there are two test cases with same name
"ALU64_SMOD_X: -7 % 2 = -1", the first one is right,
the second one should be ALU64_SMOD_K because its
code is BPF_ALU64 | BPF_MOD | BPF_K.

Before:
test_bpf: #170 ALU64_SMOD_X: -7 % 2 = -1 jited:1 4 PASS
test_bpf: #171 ALU64_SMOD_X: -7 % 2 = -1 jited:1 4 PASS

After:
test_bpf: #170 ALU64_SMOD_X: -7 % 2 = -1 jited:1 4 PASS
test_bpf: #171 ALU64_SMOD_K: -7 % 2 = -1 jited:1 4 PASS

Fixes: daabb2b098e0 ("bpf/tests: add tests for cpuv4 instructions")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231207040851.19730-1-yangtiezhu@loongson.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf/tests: Remove duplicate JSGT tests

It seems unnecessary that JSGT is tested twice (one before JSGE and one
after JSGE) since others are tested only once. Remove the duplicate JSGT
tests.

Fixes:

bpf/tests: Remove duplicate JSGT tests

It seems unnecessary that JSGT is tested twice (one before JSGE and one
after JSGE) since others are tested only once. Remove the duplicate JSGT
tests.

Fixes: 0bbaa02b4816 ("bpf/tests: Add tests to check source register zero-extension")
Signed-off-by: Yujie Liu <yujie.liu@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Link: https://lore.kernel.org/bpf/20231130034018.2144963-1-yujie.liu@intel.com

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bpf: Remove test for MOVSX32 with offset=32

MOVSX32 only supports sign extending 8-bit and 16-bit operands into 32
bit operands. The "ALU_MOVSX | BPF_W" test tries to sign extend a 32 bit
operand in

bpf: Remove test for MOVSX32 with offset=32

MOVSX32 only supports sign extending 8-bit and 16-bit operands into 32
bit operands. The "ALU_MOVSX | BPF_W" test tries to sign extend a 32 bit
operand into a 32 bit operand which is equivalent to a normal BPF_MOV.

Remove this test as it tries to run an invalid instruction.

Fixes: daabb2b098e0 ("bpf/tests: add tests for cpuv4 instructions")
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202310111838.46ff5b6a-oliver.sang@intel.com
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231110175150.87803-1-puranjay12@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf/tests: add tests for cpuv4 instructions

The BPF JITs now support cpuv4 instructions. Add tests for these new
instructions to the test suite:

1. Sign extended Load
2. Sign extended Mov
3. Uncond

bpf/tests: add tests for cpuv4 instructions

The BPF JITs now support cpuv4 instructions. Add tests for these new
instructions to the test suite:

1. Sign extended Load
2. Sign extended Mov
3. Unconditional byte swap
4. Unconditional jump with 32-bit offset
5. Signed division and modulo

Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Link: https://lore.kernel.org/r/20230907230550.1417590-9-puranjay12@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf/tests: Enhance output on error and fix typos

If a testcase returns a wrong (unexpected) value, print the expected and
returned value in hex notation in addition to the decimal notation.

This is

bpf/tests: Enhance output on error and fix typos

If a testcase returns a wrong (unexpected) value, print the expected and
returned value in hex notation in addition to the decimal notation.

This is very useful in tests which bit-shift hex values left or right and
helped me a lot while developing the JIT compiler for the hppa architecture.

Additionally fix two typos: dowrd -> dword, tall calls -> tail calls.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/ZN6ZAAVoWZpsD1Jf@p100

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lib/test_bpf: Call page_address() on page acquired with GFP_KERNEL flag

generate_test_data() acquires a page with alloc_page(GFP_KERNEL).
The GFP_KERNEL is typical for kernel-internal allocations. T

lib/test_bpf: Call page_address() on page acquired with GFP_KERNEL flag

generate_test_data() acquires a page with alloc_page(GFP_KERNEL).
The GFP_KERNEL is typical for kernel-internal allocations. The
caller requires ZONE_NORMAL or a lower zone for direct access.

Therefore the page cannot come from ZONE_HIGHMEM. Thus there's no
need to map it with kmap().

Also, the kmap() is being deprecated in favor of kmap_local_page() [1].

Hence, use a plain page_address() directly.

Since the page passed to the page_address() is not from the highmem
zone, the page_address() function will always return a valid kernel
virtual address and will not return NULL. Hence, remove the check
'if (!ptr)'.

Remove the unused variable 'ptr' and label 'err_free_page'.

[1] https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com/

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Sumitra Sharma <sumitraartsy@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/bpf/20230623151644.GA434468@sumitra.com

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bpf/tests: Use struct_size()

Use struct_size() instead of hand writing it. This is less verbose and
more informative.

Signed-off-by: Su Hui <suhui@nfschina.com>
Signed-off-by: Daniel Borkmann <dani

bpf/tests: Use struct_size()

Use struct_size() instead of hand writing it. This is less verbose and
more informative.

Signed-off-by: Su Hui <suhui@nfschina.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230531043251.989312-1-suhui@nfschina.com

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net: remove skb->vlan_present

skb->vlan_present seems redundant.

We can instead derive it from this boolean expression:

vlan_present = skb->vlan_proto != 0 || skb->vlan_tci != 0

Add a new union,

net: remove skb->vlan_present

skb->vlan_present seems redundant.

We can instead derive it from this boolean expression:

vlan_present = skb->vlan_proto != 0 || skb->vlan_tci != 0

Add a new union, to access both fields in a single load/store
when possible.

union {
u32 vlan_all;
struct {
__be16 vlan_proto;
__u16 vlan_tci;
};
};

This allows following patch to remove a conditional test in GRO stack.

Note:
We move remcsum_offload to keep TC_AT_INGRESS_MASK
and SKB_MONO_DELIVERY_TIME_MASK unchanged.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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test_bpf: fix incorrect netdev features

The prototype of .features is netdev_features_t, it should use
NETIF_F_LLTX and NETIF_F_HW_VLAN_STAG_TX, not NETIF_F_LLTX_BIT
and NETIF_F_HW_VLAN_STAG_TX_BIT.

test_bpf: fix incorrect netdev features

The prototype of .features is netdev_features_t, it should use
NETIF_F_LLTX and NETIF_F_HW_VLAN_STAG_TX, not NETIF_F_LLTX_BIT
and NETIF_F_HW_VLAN_STAG_TX_BIT.

Fixes: cf204a718357 ("bpf, testing: Introduce 'gso_linear_no_head_frag' skb_segment test")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20220622135002.8263-1-shenjian15@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf, tests: Add load store test case for tail call

Add test case to enusre that the caller and callee's fp offsets are
correct during tail call (mainly asserting for arm64 JIT).

Tested on both big-

bpf, tests: Add load store test case for tail call

Add test case to enusre that the caller and callee's fp offsets are
correct during tail call (mainly asserting for arm64 JIT).

Tested on both big-endian and little-endian arm64 qemu, result:

test_bpf: Summary: 1026 PASSED, 0 FAILED, [1014/1014 JIT'ed]
test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed]
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED

Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220321152852.2334294-6-xukuohai@huawei.com

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bpf, tests: Add tests for BPF_LDX/BPF_STX with different offsets

This patch adds tests to verify the behavior of BPF_LDX/BPF_STX +
BPF_B/BPF_H/BPF_W/BPF_DW with negative offset, small positive offse

bpf, tests: Add tests for BPF_LDX/BPF_STX with different offsets

This patch adds tests to verify the behavior of BPF_LDX/BPF_STX +
BPF_B/BPF_H/BPF_W/BPF_DW with negative offset, small positive offset,
large positive offset, and misaligned offset.

Tested on both big-endian and little-endian arm64 qemu, result:

test_bpf: Summary: 1026 PASSED, 0 FAILED, [1014/1014 JIT'ed]']
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [8/8 JIT'ed]
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED

Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220321152852.2334294-5-xukuohai@huawei.com

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bpf: Change value of MAX_TAIL_CALL_CNT from 32 to 33

In the current code, the actual max tail call count is 33 which is greater
than MAX_TAIL_CALL_CNT (defined as 32). The actual limit is not consis

bpf: Change value of MAX_TAIL_CALL_CNT from 32 to 33

In the current code, the actual max tail call count is 33 which is greater
than MAX_TAIL_CALL_CNT (defined as 32). The actual limit is not consistent
with the meaning of MAX_TAIL_CALL_CNT and thus confusing at first glance.
We can see the historical evolution from commit 04fd61ab36ec ("bpf: allow
bpf programs to tail-call other bpf programs") and commit f9dabe016b63
("bpf: Undo off-by-one in interpreter tail call count limit"). In order
to avoid changing existing behavior, the actual limit is 33 now, this is
reasonable.

After commit 874be05f525e ("bpf, tests: Add tail call test suite"), we can
see there exists failed testcase.

On all archs when CONFIG_BPF_JIT_ALWAYS_ON is not set:
# echo 0 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf
# dmesg | grep -w FAIL
Tail call error path, max count reached jited:0 ret 34 != 33 FAIL

On some archs:
# echo 1 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf
# dmesg | grep -w FAIL
Tail call error path, max count reached jited:1 ret 34 != 33 FAIL

Although the above failed testcase has been fixed in commit 18935a72eb25
("bpf/tests: Fix error in tail call limit tests"), it would still be good
to change the value of MAX_TAIL_CALL_CNT from 32 to 33 to make the code
more readable.

The 32-bit x86 JIT was using a limit of 32, just fix the wrong comments and
limit to 33 tail calls as the constant MAX_TAIL_CALL_CNT updated. For the
mips64 JIT, use "ori" instead of "addiu" as suggested by Johan Almbladh.
For the riscv JIT, use RV_REG_TCC directly to save one register move as
suggested by Björn Töpel. For the other implementations, no function changes,
it does not change the current limit 33, the new value of MAX_TAIL_CALL_CNT
can reflect the actual max tail call count, the related tail call testcases
in test_bpf module and selftests can work well for the interpreter and the
JIT.

Here are the test results on x86_64:

# uname -m
x86_64
# echo 0 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf test_suite=test_tail_calls
# dmesg | tail -1
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
# rmmod test_bpf
# echo 1 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf test_suite=test_tail_calls
# dmesg | tail -1
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [8/8 JIT'ed]
# rmmod test_bpf
# ./test_progs -t tailcalls
#142 tailcalls:OK
Summary: 1/11 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/1636075800-3264-1-git-send-email-yangtiezhu@loongson.cn

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bpf, tests: Add module parameter test_suite to test_bpf module

After commit 9298e63eafea ("bpf/tests: Add exhaustive tests of ALU
operand magnitudes"), when modprobe test_bpf.ko with JIT on mips64,

bpf, tests: Add module parameter test_suite to test_bpf module

After commit 9298e63eafea ("bpf/tests: Add exhaustive tests of ALU
operand magnitudes"), when modprobe test_bpf.ko with JIT on mips64,
there exists segment fault due to the following reason:

[...]
ALU64_MOV_X: all register value magnitudes jited:1
Break instruction in kernel code[#1]
[...]

It seems that the related JIT implementations of some test cases
in test_bpf() have problems. At this moment, I do not care about
the segment fault while I just want to verify the test cases of
tail calls.

Based on the above background and motivation, add the following
module parameter test_suite to the test_bpf.ko:

test_suite=<string>: only the specified test suite will be run, the
string can be "test_bpf", "test_tail_calls" or "test_skb_segment".

If test_suite is not specified, but test_id, test_name or test_range
is specified, set 'test_bpf' as the default test suite. This is useful
to only test the corresponding test suite when specifying the valid
test_suite string.

Any invalid test suite will result in -EINVAL being returned and no
tests being run. If the test_suite is not specified or specified as
empty string, it does not change the current logic, all of the test
cases will be run.

Here are some test results:

# dmesg -c
# modprobe test_bpf
# dmesg | grep Summary
test_bpf: Summary: 1009 PASSED, 0 FAILED, [0/997 JIT'ed]
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_bpf
# dmesg | tail -1
test_bpf: Summary: 1009 PASSED, 0 FAILED, [0/997 JIT'ed]

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_tail_calls
# dmesg
test_bpf: #0 Tail call leaf jited:0 21 PASS
[...]
test_bpf: #7 Tail call error path, index out of range jited:0 32 PASS
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_skb_segment
# dmesg
test_bpf: #0 gso_with_rx_frags PASS
test_bpf: #1 gso_linear_no_head_frag PASS
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_id=1
# dmesg
test_bpf: test_bpf: set 'test_bpf' as the default test_suite.
test_bpf: #1 TXA jited:0 54 51 50 PASS
test_bpf: Summary: 1 PASSED, 0 FAILED, [0/1 JIT'ed]

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_bpf test_name=TXA
# dmesg
test_bpf: #1 TXA jited:0 54 50 51 PASS
test_bpf: Summary: 1 PASSED, 0 FAILED, [0/1 JIT'ed]

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_tail_calls test_range=6,7
# dmesg
test_bpf: #6 Tail call error path, NULL target jited:0 41 PASS
test_bpf: #7 Tail call error path, index out of range jited:0 32 PASS
test_bpf: test_tail_calls: Summary: 2 PASSED, 0 FAILED, [0/2 JIT'ed]

# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_skb_segment test_id=1
# dmesg
test_bpf: #1 gso_linear_no_head_frag PASS
test_bpf: test_skb_segment: Summary: 1 PASSED, 0 FAILED

By the way, the above segment fault has been fixed in the latest bpf-next
tree which contains the mips64 JIT rework.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Link: https://lore.kernel.org/bpf/1635384321-28128-1-git-send-email-yangtiezhu@loongson.cn

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bpf, tests: Add more LD_IMM64 tests

This patch adds new tests for the two-instruction LD_IMM64. The new tests
verify the operation with immediate values of different byte patterns.
Mainly intended t

bpf, tests: Add more LD_IMM64 tests

This patch adds new tests for the two-instruction LD_IMM64. The new tests
verify the operation with immediate values of different byte patterns.
Mainly intended to cover JITs that want to be clever when loading 64-bit
constants.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211007143006.634308-1-johan.almbladh@anyfinetworks.com

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bpf/tests: Add test of LDX_MEM with operand aliasing

This patch adds a set of tests of BPF_LDX_MEM where both operand registers
are the same register. Mainly testing 32-bit JITs that may load a 64-b

bpf/tests: Add test of LDX_MEM with operand aliasing

This patch adds a set of tests of BPF_LDX_MEM where both operand registers
are the same register. Mainly testing 32-bit JITs that may load a 64-bit
value in two 32-bit loads, and must not overwrite the address register.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-11-johan.almbladh@anyfinetworks.com

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bpf/tests: Add test of ALU shifts with operand register aliasing

This patch adds a tests of ALU32 and ALU64 LSH/RSH/ARSH operations for the
case when the two operands are the same register. Mainly i

bpf/tests: Add test of ALU shifts with operand register aliasing

This patch adds a tests of ALU32 and ALU64 LSH/RSH/ARSH operations for the
case when the two operands are the same register. Mainly intended to test
JITs that implement ALU64 shifts with 32-bit CPU instructions.

Also renamed related helper functions for consistency with the new tests.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-10-johan.almbladh@anyfinetworks.com

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bpf/tests: Add exhaustive tests of BPF_ATOMIC register combinations

This patch adds tests of all register combinations for BPF_ATOMIC
operations on both BPF_W and BPF_DW sizes.

Signed-off-by: Johan

bpf/tests: Add exhaustive tests of BPF_ATOMIC register combinations

This patch adds tests of all register combinations for BPF_ATOMIC
operations on both BPF_W and BPF_DW sizes.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-9-johan.almbladh@anyfinetworks.com

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bpf/tests: Add exhaustive tests of ALU register combinations

This patch replaces the current register combination test with new
exhaustive tests. Before, only a subset of register combinations was
t

bpf/tests: Add exhaustive tests of ALU register combinations

This patch replaces the current register combination test with new
exhaustive tests. Before, only a subset of register combinations was
tested for ALU64 DIV. Now, all combinatons of operand registers are
tested, including the case when they are the same, and for all ALU32
and ALU64 operations.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-8-johan.almbladh@anyfinetworks.com

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bpf/tests: Minor restructuring of ALU tests

This patch moves the ALU LSH/RSH/ARSH reference computations into the
common reference value function. Also fix typo in constants so they
now have the int

bpf/tests: Minor restructuring of ALU tests

This patch moves the ALU LSH/RSH/ARSH reference computations into the
common reference value function. Also fix typo in constants so they
now have the intended values.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-7-johan.almbladh@anyfinetworks.com

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bpf/tests: Add more tests for ALU and ATOMIC register clobbering

This patch expands the register-clobbering-during-function-call tests
to cover more all ALU32/64 MUL, DIV and MOD operations and all

bpf/tests: Add more tests for ALU and ATOMIC register clobbering

This patch expands the register-clobbering-during-function-call tests
to cover more all ALU32/64 MUL, DIV and MOD operations and all ATOMIC
operations. In short, if a JIT implements a complex operation with
a call to an external function, it must make sure to save and restore
all its caller-saved registers that may be clobbered by the call.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-6-johan.almbladh@anyfinetworks.com

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bpf/tests: Add tests to check source register zero-extension

This patch adds tests to check that the source register is preserved when
zero-extending a 32-bit value. In particular, it checks that th

bpf/tests: Add tests to check source register zero-extension

This patch adds tests to check that the source register is preserved when
zero-extending a 32-bit value. In particular, it checks that the source
operand is not zero-extended in-place.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-5-johan.almbladh@anyfinetworks.com

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bpf/tests: Add exhaustive tests of BPF_ATOMIC magnitudes

This patch adds a series of test to verify the operation of BPF_ATOMIC
with BPF_DW and BPF_W sizes, for all power-of-two magnitudes of the
re

bpf/tests: Add exhaustive tests of BPF_ATOMIC magnitudes

This patch adds a series of test to verify the operation of BPF_ATOMIC
with BPF_DW and BPF_W sizes, for all power-of-two magnitudes of the
register value operand.

Also fixes a confusing typo in the comment for a related test.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-4-johan.almbladh@anyfinetworks.com

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bpf/tests: Add zero-extension checks in BPF_ATOMIC tests

This patch updates the existing tests of BPF_ATOMIC operations to verify
that a 32-bit register operand is properly zero-extended. In particu

bpf/tests: Add zero-extension checks in BPF_ATOMIC tests

This patch updates the existing tests of BPF_ATOMIC operations to verify
that a 32-bit register operand is properly zero-extended. In particular,
it checks the operation on archs that require 32-bit operands to be
properly zero-/sign-extended or the result is undefined, e.g. MIPS64.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-3-johan.almbladh@anyfinetworks.com

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bpf/tests: Add tests of BPF_LDX and BPF_STX with small sizes

This patch adds a series of tests to verify the behavior of BPF_LDX and
BPF_STX with BPF_B//W sizes in isolation. In particular, it check

bpf/tests: Add tests of BPF_LDX and BPF_STX with small sizes

This patch adds a series of tests to verify the behavior of BPF_LDX and
BPF_STX with BPF_B//W sizes in isolation. In particular, it checks that
BPF_LDX zero-extendeds the result, and that BPF_STX does not overwrite
adjacent bytes in memory.

BPF_ST and operations on BPF_DW size are deemed to be sufficiently
tested by existing tests.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-2-johan.almbladh@anyfinetworks.com

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bpf: Replace "want address" users of BPF_CAST_CALL with BPF_CALL_IMM

In order to keep ahead of cases in the kernel where Control Flow
Integrity (CFI) may trip over function call casts, enabling
-Wca

bpf: Replace "want address" users of BPF_CAST_CALL with BPF_CALL_IMM

In order to keep ahead of cases in the kernel where Control Flow
Integrity (CFI) may trip over function call casts, enabling
-Wcast-function-type is helpful. To that end, BPF_CAST_CALL causes
various warnings and is one of the last places in the kernel triggering
this warning.

Most places using BPF_CAST_CALL actually just want a void * to perform
math on. It's not actually performing a call, so just use a different
helper to get the void *, by way of the new BPF_CALL_IMM() helper, which
can clean up a common copy/paste idiom as well.

This change results in no object code difference.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://github.com/KSPP/linux/issues/20
Link: https://lore.kernel.org/lkml/CAEf4Bzb46=-J5Fxc3mMZ8JQPtK1uoE0q6+g6WPz53Cvx=CBEhw@mail.gmail.com
Link: https://lore.kernel.org/bpf/20210928230946.4062144-2-keescook@chromium.org

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