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author | Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | 2017-12-04 12:56:45 +0300 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2017-12-05 17:02:41 +0300 |
commit | 466698e654e8931945301ea999feb6bd4bfaf849 (patch) | |
tree | 8cb41d1ca11de90b460984e8142e30a3903938a5 | |
parent | c895f6f703ad7dd2f99e751d9884b0aa5d0eea25 (diff) | |
download | linux-466698e654e8931945301ea999feb6bd4bfaf849.tar.xz |
s390/bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type
To mitigate and correct the broken uapi for the BPF_PROG_TYPE_PERF_EVENT
program type, introduce a user_pt_regs structure (similar to arm64) that
exports parts from the beginnig of the pt_regs structure.
The export must start with the beginning of the pt_regs structure because
to correctly calculate BPF prologues for perf (regs_query_register_offset()).
For BPF_PROG_TYPE_PERF_EVENT program types, the BPF program is then passed
a user_pt_regs structure.
Note: Depending on future changes to the s390 pt_regs structure, consider
the user_pt_regs structure to be stable for a particular kernel version
only. (Of course, s390 tries to ensure keep it stable as much as possible.)
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-rw-r--r-- | arch/s390/include/asm/perf_event.h | 1 | ||||
-rw-r--r-- | arch/s390/include/asm/ptrace.h | 11 | ||||
-rw-r--r-- | arch/s390/include/uapi/asm/bpf_perf_event.h | 9 | ||||
-rw-r--r-- | arch/s390/include/uapi/asm/ptrace.h | 11 |
4 files changed, 29 insertions, 3 deletions
diff --git a/arch/s390/include/asm/perf_event.h b/arch/s390/include/asm/perf_event.h index d6c9d1e0dc2d..b9c0e361748b 100644 --- a/arch/s390/include/asm/perf_event.h +++ b/arch/s390/include/asm/perf_event.h @@ -40,6 +40,7 @@ struct pt_regs; extern unsigned long perf_instruction_pointer(struct pt_regs *regs); extern unsigned long perf_misc_flags(struct pt_regs *regs); #define perf_misc_flags(regs) perf_misc_flags(regs) +#define perf_arch_bpf_user_pt_regs(regs) ®s->user_regs /* Perf pt_regs extension for sample-data-entry indicators */ struct perf_sf_sde_regs { diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h index a3788dafc0e1..6f70d81c40f2 100644 --- a/arch/s390/include/asm/ptrace.h +++ b/arch/s390/include/asm/ptrace.h @@ -74,9 +74,14 @@ enum { */ struct pt_regs { - unsigned long args[1]; - psw_t psw; - unsigned long gprs[NUM_GPRS]; + union { + user_pt_regs user_regs; + struct { + unsigned long args[1]; + psw_t psw; + unsigned long gprs[NUM_GPRS]; + }; + }; unsigned long orig_gpr2; unsigned int int_code; unsigned int int_parm; diff --git a/arch/s390/include/uapi/asm/bpf_perf_event.h b/arch/s390/include/uapi/asm/bpf_perf_event.h new file mode 100644 index 000000000000..cefe7c7cd4f6 --- /dev/null +++ b/arch/s390/include/uapi/asm/bpf_perf_event.h @@ -0,0 +1,9 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _UAPI__ASM_BPF_PERF_EVENT_H__ +#define _UAPI__ASM_BPF_PERF_EVENT_H__ + +#include <asm/ptrace.h> + +typedef user_pt_regs bpf_user_pt_regs_t; + +#endif /* _UAPI__ASM_BPF_PERF_EVENT_H__ */ diff --git a/arch/s390/include/uapi/asm/ptrace.h b/arch/s390/include/uapi/asm/ptrace.h index 0d23c8ff2900..70f7cb2e5e50 100644 --- a/arch/s390/include/uapi/asm/ptrace.h +++ b/arch/s390/include/uapi/asm/ptrace.h @@ -291,6 +291,17 @@ typedef struct } s390_regs; /* + * The user_pt_regs structure exports the beginning of + * the in-kernel pt_regs structure to user space. + */ +typedef struct +{ + unsigned long args[1]; + psw_t psw; + unsigned long gprs[NUM_GPRS]; +} user_pt_regs; + +/* * Now for the user space program event recording (trace) definitions. * The following structures are used only for the ptrace interface, don't * touch or even look at it if you don't want to modify the user-space |