From b8ebce86ffe655ac15a841bba2d645105ffe3d38 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 13 Mar 2020 10:23:35 -0700 Subject: [PATCH] libbpf: Provide CO-RE variants of PT_REGS macros Syscall raw tracepoints have struct pt_regs pointer as tracepoint's first argument. After that, reading any of pt_regs fields requires bpf_probe_read(), even for tp_btf programs. Due to that, PT_REGS_PARMx macros are not usable as is. This patch adds CO-RE variants of those macros that use BPF_CORE_READ() to read necessary fields. This provides relocatable architecture-agnostic pt_regs field accesses. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20200313172336.1879637-4-andriin@fb.com --- tools/lib/bpf/bpf_tracing.h | 103 ++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 379d03b211ea..b0c9ae5c73b5 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -50,6 +50,7 @@ #if defined(bpf_target_x86) #if defined(__KERNEL__) || defined(__VMLINUX_H__) + #define PT_REGS_PARM1(x) ((x)->di) #define PT_REGS_PARM2(x) ((x)->si) #define PT_REGS_PARM3(x) ((x)->dx) @@ -60,7 +61,20 @@ #define PT_REGS_RC(x) ((x)->ax) #define PT_REGS_SP(x) ((x)->sp) #define PT_REGS_IP(x) ((x)->ip) + +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), di) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), si) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), dx) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), cx) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), r8) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), sp) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), bp) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), ax) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), sp) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), ip) + #else + #ifdef __i386__ /* i386 kernel is built with -mregparm=3 */ #define PT_REGS_PARM1(x) ((x)->eax) @@ -73,7 +87,20 @@ #define PT_REGS_RC(x) ((x)->eax) #define PT_REGS_SP(x) ((x)->esp) #define PT_REGS_IP(x) ((x)->eip) + +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), eax) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), edx) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), ecx) +#define PT_REGS_PARM4_CORE(x) 0 +#define PT_REGS_PARM5_CORE(x) 0 +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), esp) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), ebp) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), eax) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), esp) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), eip) + #else + #define PT_REGS_PARM1(x) ((x)->rdi) #define PT_REGS_PARM2(x) ((x)->rsi) #define PT_REGS_PARM3(x) ((x)->rdx) @@ -84,6 +111,18 @@ #define PT_REGS_RC(x) ((x)->rax) #define PT_REGS_SP(x) ((x)->rsp) #define PT_REGS_IP(x) ((x)->rip) + +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), rdi) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), rsi) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), rdx) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), rcx) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), r8) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), rsp) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), rbp) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), rax) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), rsp) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), rip) + #endif #endif @@ -104,6 +143,17 @@ struct pt_regs; #define PT_REGS_SP(x) (((PT_REGS_S390 *)(x))->gprs[15]) #define PT_REGS_IP(x) (((PT_REGS_S390 *)(x))->psw.addr) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[2]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[3]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[4]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[5]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[6]) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), grps[14]) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[11]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[2]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), gprs[15]) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((PT_REGS_S390 *)(x), pdw.addr) + #elif defined(bpf_target_arm) #define PT_REGS_PARM1(x) ((x)->uregs[0]) @@ -117,6 +167,17 @@ struct pt_regs; #define PT_REGS_SP(x) ((x)->uregs[13]) #define PT_REGS_IP(x) ((x)->uregs[12]) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), uregs[0]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), uregs[1]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), uregs[2]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), uregs[3]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), uregs[4]) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), uregs[14]) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), uregs[11]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), uregs[0]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), uregs[13]) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), uregs[12]) + #elif defined(bpf_target_arm64) /* arm64 provides struct user_pt_regs instead of struct pt_regs to userspace */ @@ -134,6 +195,17 @@ struct pt_regs; #define PT_REGS_SP(x) (((PT_REGS_ARM64 *)(x))->sp) #define PT_REGS_IP(x) (((PT_REGS_ARM64 *)(x))->pc) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[0]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[1]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[2]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[3]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[4]) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[30]) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[29]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), regs[0]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), sp) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((PT_REGS_ARM64 *)(x), pc) + #elif defined(bpf_target_mips) #define PT_REGS_PARM1(x) ((x)->regs[4]) @@ -147,6 +219,17 @@ struct pt_regs; #define PT_REGS_SP(x) ((x)->regs[29]) #define PT_REGS_IP(x) ((x)->cp0_epc) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), regs[4]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), regs[5]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), regs[6]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), regs[7]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), regs[8]) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), regs[31]) +#define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), regs[30]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), regs[1]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), regs[29]) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), cp0_epc) + #elif defined(bpf_target_powerpc) #define PT_REGS_PARM1(x) ((x)->gpr[3]) @@ -158,6 +241,15 @@ struct pt_regs; #define PT_REGS_SP(x) ((x)->sp) #define PT_REGS_IP(x) ((x)->nip) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), gpr[3]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), gpr[4]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), gpr[5]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), gpr[6]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), gpr[7]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), gpr[3]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), sp) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), nip) + #elif defined(bpf_target_sparc) #define PT_REGS_PARM1(x) ((x)->u_regs[UREG_I0]) @@ -169,11 +261,22 @@ struct pt_regs; #define PT_REGS_RC(x) ((x)->u_regs[UREG_I0]) #define PT_REGS_SP(x) ((x)->u_regs[UREG_FP]) +#define PT_REGS_PARM1_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I0]) +#define PT_REGS_PARM2_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I1]) +#define PT_REGS_PARM3_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I2]) +#define PT_REGS_PARM4_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I3]) +#define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I4]) +#define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I7]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), u_regs[UREG_I0]) +#define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), u_regs[UREG_FP]) + /* Should this also be a bpf_target check for the sparc case? */ #if defined(__arch64__) #define PT_REGS_IP(x) ((x)->tpc) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), tpc) #else #define PT_REGS_IP(x) ((x)->pc) +#define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), pc) #endif #endif -- 2.34.1