// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_core_read.h>
#include "../../../include/linux/filter.h"
#include "bpf_misc.h"
#include <stdbool.h>
#include "bpf_kfuncs.h"
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 8")
__xlated("4: r5 = 5")
__xlated("5: w0 = ")
__xlated("6: r0 = &(void __percpu *)(r0)")
__xlated("7: r0 = *(u32 *)(r0 +0)")
__xlated("8: exit")
__success
__naked void simple(void)
{
asm volatile (
"r1 = 1;"
"r2 = 2;"
"r3 = 3;"
"r4 = 4;"
"r5 = 5;"
"*(u64 *)(r10 - 16) = r1;"
"*(u64 *)(r10 - 24) = r2;"
"*(u64 *)(r10 - 32) = r3;"
"*(u64 *)(r10 - 40) = r4;"
"*(u64 *)(r10 - 48) = r5;"
"call %[bpf_get_smp_processor_id];"
"r5 = *(u64 *)(r10 - 48);"
"r4 = *(u64 *)(r10 - 40);"
"r3 = *(u64 *)(r10 - 32);"
"r2 = *(u64 *)(r10 - 24);"
"r1 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
/* The logic for detecting and verifying bpf_fastcall pattern is the same for
* any arch, however x86 differs from arm64 or riscv64 in a way
* bpf_get_smp_processor_id is rewritten:
* - on x86 it is done by verifier
* - on arm64 and riscv64 it is done by jit
*
* Which leads to different xlated patterns for different archs:
* - on x86 the call is expanded as 3 instructions
* - on arm64 and riscv64 the call remains as is
* (but spills/fills are still removed)
*
* It is really desirable to check instruction indexes in the xlated
* patterns, so add this canary test to check that function rewrite by
* jit is correctly processed by bpf_fastcall logic, keep the rest of the
* tests as x86.
*/
SEC("raw_tp")
__arch_arm64
__arch_riscv64
__xlated("0: r1 = 1")
__xlated("1: call bpf_get_smp_processor_id")
__xlated("2: exit")
__success
__naked void canary_arm64_riscv64(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("3: exit")
__success
__naked void canary_zero_spills(void)
{
asm volatile (
"call %[bpf_get_smp_processor_id];"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 16")
__xlated("1: *(u64 *)(r10 -16) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r2 = *(u64 *)(r10 -16)")
__success
__naked void wrong_reg_in_pattern1(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r2 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -16) = r6")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r6 = *(u64 *)(r10 -16)")
__success
__naked void wrong_reg_in_pattern2(void)
{
asm volatile (
"r6 = 1;"
"*(u64 *)(r10 - 16) = r6;"
"call %[bpf_get_smp_processor_id];"
"r6 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -16) = r0")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r0 = *(u64 *)(r10 -16)")
__success
__naked void wrong_reg_in_pattern3(void)
{
asm volatile (
"r0 = 1;"
"*(u64 *)(r10 - 16) = r0;"
"call %[bpf_get_smp_processor_id];"
"r0 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("2: *(u64 *)(r2 -16) = r1")
__xlated("...")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("6: r1 = *(u64 *)(r10 -16)")
__success
__naked void wrong_base_in_pattern(void)
{
asm volatile (
"r1 = 1;"
"r2 = r10;"
"*(u64 *)(r2 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -16) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r2 = 1")
__success
__naked void wrong_insn_in_pattern(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r2 = 1;"
"r1 = *(u64 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("2: *(u64 *)(r10 -16) = r1")
__xlated("...")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("6: r1 = *(u64 *)(r10 -8)")
__success
__naked void wrong_off_in_pattern1(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u32 *)(r10 -4) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u32 *)(r10 -4)")
__success
__naked void wrong_off_in_pattern2(void)
{
asm volatile (
"r1 = 1;"
"*(u32 *)(r10 - 4) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u32 *)(r10 - 4);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u32 *)(r10 -16) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u32 *)(r10 -16)")
__success
__naked void wrong_size_in_pattern(void)
{
asm volatile (
"r1 = 1;"
"*(u32 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u32 *)(r10 - 16);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("2: *(u32 *)(r10 -8) = r1")
__xlated("...")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("6: r1 = *(u32 *)(r10 -8)")
__success
__naked void partial_pattern(void)
{
asm volatile (
"r1 = 1;"
"r2 = 2;"
"*(u32 *)(r10 - 8) = r1;"
"*(u64 *)(r10 - 16) = r2;"
"call %[bpf_get_smp_processor_id];"
"r2 = *(u64 *)(r10 - 16);"
"r1 = *(u32 *)(r10 - 8);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("0: r1 = 1")
__xlated("1: r2 = 2")
/* not patched, spills for -8, -16 not removed */
__xlated("2: *(u64 *)(r10 -8) = r1")
__xlated("3: *(u64 *)(r10 -16) = r2")
__xlated("...")
__xlated("5: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("7: r2 = *(u64 *)(r10 -16)")
__xlated("8: r1 = *(u64 *)(r10 -8)")
/* patched, spills for -24, -32 removed */
__xlated("...")
__xlated("10: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("12: exit")
__success
__naked void min_stack_offset(void)
{
asm volatile (
"r1 = 1;"
"r2 = 2;"
/* this call won't be patched */
"*(u64 *)(r10 - 8) = r1;"
"*(u64 *)(r10 - 16) = r2;"
"call %[bpf_get_smp_processor_id];"
"r2 = *(u64 *)(r10 - 16);"
"r1 = *(u64 *)(r10 - 8);"
/* this call would be patched */
"*(u64 *)(r10 - 24) = r1;"
"*(u64 *)(r10 - 32) = r2;"
"call %[bpf_get_smp_processor_id];"
"r2 = *(u64 *)(r10 - 32);"
"r1 = *(u64 *)(r10 - 24);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -8) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u64 *)(r10 -8)")
__success
__naked void bad_fixed_read(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"r1 = r10;"
"r1 += -8;"
"r1 = *(u64 *)(r1 - 0);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -8) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u64 *)(r10 -8)")
__success
__naked void bad_fixed_write(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"r1 = r10;"
"r1 += -8;"
"*(u64 *)(r1 - 0) = r1;"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("6: *(u64 *)(r10 -16) = r1")
__xlated("...")
__xlated("8: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("10: r1 = *(u64 *)(r10 -16)")
__success
__naked void bad_varying_read(void)
{
asm volatile (
"r6 = *(u64 *)(r1 + 0);" /* random scalar value */
"r6 &= 0x7;" /* r6 range [0..7] */
"r6 += 0x2;" /* r6 range [2..9] */
"r7 = 0;"
"r7 -= r6;" /* r7 range [-9..-2] */
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"r1 = r10;"
"r1 += r7;"
"r1 = *(u8 *)(r1 - 0);" /* touches slot [-16..-9] where spills are stored */
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("6: *(u64 *)(r10 -16) = r1")
__xlated("...")
__xlated("8: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("10: r1 = *(u64 *)(r10 -16)")
__success
__naked void bad_varying_write(void)
{
asm volatile (
"r6 = *(u64 *)(r1 + 0);" /* random scalar value */
"r6 &= 0x7;" /* r6 range [0..7] */
"r6 += 0x2;" /* r6 range [2..9] */
"r7 = 0;"
"r7 -= r6;" /* r7 range [-9..-2] */
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"r1 = r10;"
"r1 += r7;"
"*(u8 *)(r1 - 0) = r7;" /* touches slot [-16..-9] where spills are stored */
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -8) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u64 *)(r10 -8)")
__success
__naked void bad_write_in_subprog(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"r1 = r10;"
"r1 += -8;"
"call bad_write_in_subprog_aux;"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
__used
__naked static void bad_write_in_subprog_aux(void)
{
asm volatile (
"r0 = 1;"
"*(u64 *)(r1 - 0) = r0;" /* invalidates bpf_fastcall contract for caller: */
"exit;" /* caller stack at -8 used outside of the pattern */
::: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__xlated("1: *(u64 *)(r10 -8) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u64 *)(r10 -8)")
__success
__naked void bad_helper_write(void)
{
asm volatile (
"r1 = 1;"
/* bpf_fastcall pattern with stack offset -8 */
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"r1 = r10;"
"r1 += -8;"
"r2 = 1;"
"r3 = 42;"
/* read dst is fp[-8], thus bpf_fastcall rewrite not applied */
"call %[bpf_probe_read_kernel];"
"exit;"
:
: __imm(bpf_get_smp_processor_id),
__imm(bpf_probe_read_kernel)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
/* main, not patched */
__xlated("1: *(u64 *)(r10 -8) = r1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("5: r1 = *(u64 *)(r10 -8)")
__xlated("...")
__xlated("9: call pc+1")
__xlated("...")
__xlated("10: exit")
/* subprogram, patched */
__xlated("11: r1 = 1")
__xlated("...")
__xlated("13: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("15: exit")
__success
__naked void invalidate_one_subprog(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"r1 = r10;"
"r1 += -8;"
"r1 = *(u64 *)(r1 - 0);"
"call invalidate_one_subprog_aux;"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
__used
__naked static void invalidate_one_subprog_aux(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
/* main */
__xlated("0: r1 = 1")
__xlated("...")
__xlated("2: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("4: call pc+1")
__xlated("5: exit")
/* subprogram */
__xlated("6: r1 = 1")
__xlated("...")
__xlated("8: r0 = &(void __percpu *)(r0)")
__xlated("...")
__xlated("10: *(u64 *)(r10 -16) = r1")
__xlated("11: exit")
__success
__naked void subprogs_use_independent_offsets(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"call subprogs_use_independent_offsets_aux;"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
__used
__naked static void subprogs_use_independent_offsets_aux(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 24) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 24);"
"*(u64 *)(r10 - 16) = r1;"
"exit;"
:
: __imm(bpf_get_smp_processor_id)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 8")
__xlated("2: r0 = &(void __percpu *)(r0)")
__success
__naked void helper_call_does_not_prevent_bpf_fastcall(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_prandom_u32];"
"r1 = *(u64 *)(r10 - 8);"
"exit;"
:
: __imm(bpf_get_smp_processor_id),
__imm(bpf_get_prandom_u32)
: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 16")
/* may_goto counter at -16 */
__xlated("0: *(u64 *)(r10 -16) =")
__xlated("1: r1 = 1")
__xlated("...")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("...")
/* may_goto expansion starts */
__xlated("5: r11 = *(u64 *)(r10 -16)")
__xlated("6: if r11 == 0x0 goto pc+3")
__xlated("7: r11 -= 1")
__xlated("8: *(u64 *)(r10 -16) = r11")
/* may_goto expansion ends */
__xlated("9: *(u64 *)(r10 -8) = r1")
__xlated("10: exit")
__success
__naked void may_goto_interaction(void)
{
asm volatile (
"r1 = 1;"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
".8byte %[may_goto];"
/* just touch some stack at -8 */
"*(u64 *)(r10 - 8) = r1;"
"exit;"
:
: __imm(bpf_get_smp_processor_id),
__imm_insn(may_goto, BPF_RAW_INSN(BPF_JMP | BPF_JCOND, 0, 0, +1 /* offset */, 0))
: __clobber_all);
}
__used
__naked static void dummy_loop_callback(void)
{
asm volatile (
"r0 = 0;"
"exit;"
::: __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 32+0")
__xlated("2: r1 = 1")
__xlated("3: w0 =")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("5: r0 = *(u32 *)(r0 +0)")
/* bpf_loop params setup */
__xlated("6: r2 =")
__xlated("7: r3 = 0")
__xlated("8: r4 = 0")
__xlated("...")
/* ... part of the inlined bpf_loop */
__xlated("12: *(u64 *)(r10 -32) = r6")
__xlated("13: *(u64 *)(r10 -24) = r7")
__xlated("14: *(u64 *)(r10 -16) = r8")
__xlated("...")
__xlated("21: call pc+8") /* dummy_loop_callback */
/* ... last insns of the bpf_loop_interaction1 */
__xlated("...")
__xlated("28: r0 = 0")
__xlated("29: exit")
/* dummy_loop_callback */
__xlated("30: r0 = 0")
__xlated("31: exit")
__success
__naked int bpf_loop_interaction1(void)
{
asm volatile (
"r1 = 1;"
/* bpf_fastcall stack region at -16, but could be removed */
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"r2 = %[dummy_loop_callback];"
"r3 = 0;"
"r4 = 0;"
"call %[bpf_loop];"
"r0 = 0;"
"exit;"
:
: __imm_ptr(dummy_loop_callback),
__imm(bpf_get_smp_processor_id),
__imm(bpf_loop)
: __clobber_common
);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 40+0")
/* call bpf_get_smp_processor_id */
__xlated("2: r1 = 42")
__xlated("3: w0 =")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("5: r0 = *(u32 *)(r0 +0)")
/* call bpf_get_prandom_u32 */
__xlated("6: *(u64 *)(r10 -16) = r1")
__xlated("7: call")
__xlated("8: r1 = *(u64 *)(r10 -16)")
__xlated("...")
/* ... part of the inlined bpf_loop */
__xlated("15: *(u64 *)(r10 -40) = r6")
__xlated("16: *(u64 *)(r10 -32) = r7")
__xlated("17: *(u64 *)(r10 -24) = r8")
__success
__naked int bpf_loop_interaction2(void)
{
asm volatile (
"r1 = 42;"
/* bpf_fastcall stack region at -16, cannot be removed */
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 16);"
"*(u64 *)(r10 - 16) = r1;"
"call %[bpf_get_prandom_u32];"
"r1 = *(u64 *)(r10 - 16);"
"r2 = %[dummy_loop_callback];"
"r3 = 0;"
"r4 = 0;"
"call %[bpf_loop];"
"r0 = 0;"
"exit;"
:
: __imm_ptr(dummy_loop_callback),
__imm(bpf_get_smp_processor_id),
__imm(bpf_get_prandom_u32),
__imm(bpf_loop)
: __clobber_common
);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4)
__msg("stack depth 512+0")
/* just to print xlated version when debugging */
__xlated("r0 = &(void __percpu *)(r0)")
__success
/* cumulative_stack_depth() stack usage is MAX_BPF_STACK,
* called subprogram uses an additional slot for bpf_fastcall spill/fill,
* since bpf_fastcall spill/fill could be removed the program still fits
* in MAX_BPF_STACK and should be accepted.
*/
__naked int cumulative_stack_depth(void)
{
asm volatile(
"r1 = 42;"
"*(u64 *)(r10 - %[max_bpf_stack]) = r1;"
"call cumulative_stack_depth_subprog;"
"exit;"
:
: __imm_const(max_bpf_stack, MAX_BPF_STACK)
: __clobber_all
);
}
__used
__naked static void cumulative_stack_depth_subprog(void)
{
asm volatile (
"*(u64 *)(r10 - 8) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - 8);"
"exit;"
:: __imm(bpf_get_smp_processor_id) : __clobber_all);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4)
__msg("stack depth 512")
__xlated("0: r1 = 42")
__xlated("1: *(u64 *)(r10 -512) = r1")
__xlated("2: w0 = ")
__xlated("3: r0 = &(void __percpu *)(r0)")
__xlated("4: r0 = *(u32 *)(r0 +0)")
__xlated("5: exit")
__success
__naked int bpf_fastcall_max_stack_ok(void)
{
asm volatile(
"r1 = 42;"
"*(u64 *)(r10 - %[max_bpf_stack]) = r1;"
"*(u64 *)(r10 - %[max_bpf_stack_8]) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - %[max_bpf_stack_8]);"
"exit;"
:
: __imm_const(max_bpf_stack, MAX_BPF_STACK),
__imm_const(max_bpf_stack_8, MAX_BPF_STACK + 8),
__imm(bpf_get_smp_processor_id)
: __clobber_all
);
}
SEC("raw_tp")
__arch_x86_64
__log_level(4)
__msg("stack depth 520")
__failure
__naked int bpf_fastcall_max_stack_fail(void)
{
asm volatile(
"r1 = 42;"
"*(u64 *)(r10 - %[max_bpf_stack]) = r1;"
"*(u64 *)(r10 - %[max_bpf_stack_8]) = r1;"
"call %[bpf_get_smp_processor_id];"
"r1 = *(u64 *)(r10 - %[max_bpf_stack_8]);"
/* call to prandom blocks bpf_fastcall rewrite */
"*(u64 *)(r10 - %[max_bpf_stack_8]) = r1;"
"call %[bpf_get_prandom_u32];"
"r1 = *(u64 *)(r10 - %[max_bpf_stack_8]);"
"exit;"
:
: __imm_const(max_bpf_stack, MAX_BPF_STACK),
__imm_const(max_bpf_stack_8, MAX_BPF_STACK + 8),
__imm(bpf_get_smp_processor_id),
__imm(bpf_get_prandom_u32)
: __clobber_all
);
}
SEC("cgroup/getsockname_unix")
__xlated("0: r2 = 1")
/* bpf_cast_to_kern_ctx is replaced by a single assignment */
__xlated("1: r0 = r1")
__xlated("2: r0 = r2")
__xlated("3: exit")
__success
__naked void kfunc_bpf_cast_to_kern_ctx(void)
{
asm volatile (
"r2 = 1;"
"*(u64 *)(r10 - 32) = r2;"
"call %[bpf_cast_to_kern_ctx];"
"r2 = *(u64 *)(r10 - 32);"
"r0 = r2;"
"exit;"
:
: __imm(bpf_cast_to_kern_ctx)
: __clobber_all);
}
SEC("raw_tp")
__xlated("3: r3 = 1")
/* bpf_rdonly_cast is replaced by a single assignment */
__xlated("4: r0 = r1")
__xlated("5: r0 = r3")
void kfunc_bpf_rdonly_cast(void)
{
asm volatile (
"r2 = %[btf_id];"
"r3 = 1;"
"*(u64 *)(r10 - 32) = r3;"
"call %[bpf_rdonly_cast];"
"r3 = *(u64 *)(r10 - 32);"
"r0 = r3;"
:
: __imm(bpf_rdonly_cast),
[btf_id]"r"(bpf_core_type_id_kernel(union bpf_attr))
: __clobber_common);
}
/* BTF FUNC records are not generated for kfuncs referenced
* from inline assembly. These records are necessary for
* libbpf to link the program. The function below is a hack
* to ensure that BTF FUNC records are generated.
*/
void kfunc_root(void)
{
bpf_cast_to_kern_ctx(0);
bpf_rdonly_cast(0, 0);
}
char _license[] SEC("license") = "GPL";
Codebase Browser
linux