From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0073614AB7 for ; Thu, 19 Oct 2023 08:27:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="gU/JODCp" Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB15113A; Thu, 19 Oct 2023 01:27:26 -0700 (PDT) Received: from pps.filterd (m0360072.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 39J8KWeb028111; Thu, 19 Oct 2023 08:27:23 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=ZOmmcefAxJ5+oq4SFK1clWhsG9/Bc4sHzoFO4aplk/8=; b=gU/JODCp+UsT0kwaN3AsqKsdsSVv+gCResD00t48TxrE/fj6Q7U5Mv1H6dJncdtyvMgj ZYNNTmVaCDiGQAQpBbTnodAEZgWZ41nO7PkILvEoS88Il04EAzpBNH8++YAw2E3o5p6D zER641xLlJY4mnI96b7QmOcw2soZ+j2GjRCXiv54nOoXcTiiOEMvWxGZSd4QfsYmP7HM 34kdYp3lEBFXtcPKv/N9UfzWtLaFpB0b/LgnItkERWsK16Y133ukhWHERuMV6ibor5Ef aS2m9LlProSqSBlDH1ITeonZ8yg7moChObLTCpV7x+XKDy1p3ba/1FrACwXwsuhWVUbR CA== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tu0uu0bxt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 Oct 2023 08:27:22 +0000 Received: from m0360072.ppops.net (m0360072.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 39J8KoAn028446; Thu, 19 Oct 2023 08:27:09 GMT Received: from ppma22.wdc07v.mail.ibm.com (5c.69.3da9.ip4.static.sl-reverse.com [169.61.105.92]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tu0uu0bb9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 Oct 2023 08:27:08 +0000 Received: from pps.filterd (ppma22.wdc07v.mail.ibm.com [127.0.0.1]) by ppma22.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 39J7bwjA012850; Thu, 19 Oct 2023 08:26:56 GMT Received: from smtprelay01.fra02v.mail.ibm.com ([9.218.2.227]) by ppma22.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3tr5pyqqv1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 Oct 2023 08:26:55 +0000 Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay01.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 39J8QqUI16581252 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 19 Oct 2023 08:26:52 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 91E9120043; Thu, 19 Oct 2023 08:26:52 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 68F742005A; Thu, 19 Oct 2023 08:26:52 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Thu, 19 Oct 2023 08:26:52 +0000 (GMT) From: Thomas Richter To: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, acme@kernel.org, iii@linux.ibm.com, irogers@google.com Cc: svens@linux.ibm.com, gor@linux.ibm.com, sumanthk@linux.ibm.com, hca@linux.ibm.com, Thomas Richter , Arnaldo Carvalho de Melo Subject: [PATCH] perf trace: Use the right bpf_probe_read(_str) variant for reading user data Date: Thu, 19 Oct 2023 10:26:42 +0200 Message-Id: <20231019082642.3286650-1-tmricht@linux.ibm.com> X-Mailer: git-send-email 2.39.2 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: PU7g41jItrM3CggElCzaGTVuuakomo93 X-Proofpoint-ORIG-GUID: xMS0ot7ZZ2FptzebZIEnjAih9PlqCOsE X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-19_05,2023-10-18_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 adultscore=0 mlxlogscore=999 impostorscore=0 spamscore=0 malwarescore=0 bulkscore=0 clxscore=1015 suspectscore=0 phishscore=0 lowpriorityscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310190069 Perf test case 111 Check open filename arg using perf trace + vfs_getname fails on s390. This is caused by a failing function bpf_probe_read() in file util/bpf_skel/augmented_raw_syscalls.bpf.c. The root cause is the lookup by address. Function bpf_probe_read() is used. This function works only for architectures with ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. On s390 is not possible to determine from the address to which address space the address belongs to (user or kernel space). Replace bpf_probe_read() by bpf_probe_read_kernel() and bpf_probe_read_str() by bpf_probe_read_user_str() to explicity specify the address space the address refers to. Output before: # ./perf trace -eopen,openat -- touch /tmp/111 libbpf: prog 'sys_enter': BPF program load failed: Invalid argument libbpf: prog 'sys_enter': -- BEGIN PROG LOAD LOG -- reg type unsupported for arg#0 function sys_enter#75 0: R1=ctx(off=0,imm=0) R10=fp0 ; int sys_enter(struct syscall_enter_args *args) 0: (bf) r6 = r1 ; R1=ctx(off=0,imm=0) R6_w=ctx(off=0,imm=0) ; return bpf_get_current_pid_tgid(); 1: (85) call bpf_get_current_pid_tgid#14 ; R0_w=scalar() 2: (63) *(u32 *)(r10 -8) = r0 ; R0_w=scalar() R10=fp0 fp-8=????mmmm 3: (bf) r2 = r10 ; R2_w=fp0 R10=fp0 ; ..... lines deleted here ..... 23: (bf) r3 = r6 ; R3_w=ctx(off=0,imm=0) R6=ctx(off=0,imm=0) 24: (85) call bpf_probe_read#4 unknown func bpf_probe_read#4 processed 23 insns (limit 1000000) max_states_per_insn 0 \ total_states 2 peak_states 2 mark_read 2 -- END PROG LOAD LOG -- libbpf: prog 'sys_enter': failed to load: -22 libbpf: failed to load object 'augmented_raw_syscalls_bpf' libbpf: failed to load BPF skeleton 'augmented_raw_syscalls_bpf': -22 .... Output after: # ./perf test -Fv 111 111: Check open filename arg using perf trace + vfs_getname : --- start --- 1.085 ( 0.011 ms): touch/320753 openat(dfd: CWD, filename: \ "/tmp/temporary_file.SWH85", \ flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: IRUGO|IWUGO) = 3 ---- end ---- Check open filename arg using perf trace + vfs_getname: Ok # Test with the sleep command shows: Output before: # ./perf trace -e *sleep sleep 1.234567890 0.000 (1234.681 ms): sleep/63114 clock_nanosleep(rqtp: \ { .tv_sec: 0, .tv_nsec: 0 }, rmtp: 0x3ffe0979720) = 0 # Output after: # ./perf trace -e *sleep sleep 1.234567890 0.000 (1234.686 ms): sleep/64277 clock_nanosleep(rqtp: \ { .tv_sec: 1, .tv_nsec: 234567890 }, rmtp: 0x3fff3df9ea0) = 0 # Fixes: 14e4b9f4289a ("perf trace: Raw augmented syscalls fix libbpf 1.0+ compatibility") Signed-off-by: Thomas Richter Co-developed-by: Arnaldo Carvalho de Melo Acked-by: Ilya Leoshkevich Cc: Ian Rogers --- .../util/bpf_skel/augmented_raw_syscalls.bpf.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c b/tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c index 939ec769bf4a..52c270330ae0 100644 --- a/tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c +++ b/tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c @@ -153,7 +153,7 @@ static inline unsigned int augmented_arg__read_str(struct augmented_arg *augmented_arg, const void *arg, unsigned int arg_len) { unsigned int augmented_len = sizeof(*augmented_arg); - int string_len = bpf_probe_read_str(&augmented_arg->value, arg_len, arg); + int string_len = bpf_probe_read_user_str(&augmented_arg->value, arg_len, arg); augmented_arg->size = augmented_arg->err = 0; /* @@ -203,7 +203,7 @@ int sys_enter_connect(struct syscall_enter_args *args) _Static_assert(is_power_of_2(sizeof(augmented_args->saddr)), "sizeof(augmented_args->saddr) needs to be a power of two"); socklen &= sizeof(augmented_args->saddr) - 1; - bpf_probe_read(&augmented_args->saddr, socklen, sockaddr_arg); + bpf_probe_read_user(&augmented_args->saddr, socklen, sockaddr_arg); return augmented__output(args, augmented_args, len + socklen); } @@ -221,7 +221,7 @@ int sys_enter_sendto(struct syscall_enter_args *args) socklen &= sizeof(augmented_args->saddr) - 1; - bpf_probe_read(&augmented_args->saddr, socklen, sockaddr_arg); + bpf_probe_read_user(&augmented_args->saddr, socklen, sockaddr_arg); return augmented__output(args, augmented_args, len + socklen); } @@ -311,7 +311,7 @@ int sys_enter_perf_event_open(struct syscall_enter_args *args) if (augmented_args == NULL) goto failure; - if (bpf_probe_read(&augmented_args->__data, sizeof(*attr), attr) < 0) + if (bpf_probe_read_user(&augmented_args->__data, sizeof(*attr), attr) < 0) goto failure; attr_read = (const struct perf_event_attr_size *)augmented_args->__data; @@ -325,7 +325,7 @@ int sys_enter_perf_event_open(struct syscall_enter_args *args) goto failure; // Now that we read attr->size and tested it against the size limits, read it completely - if (bpf_probe_read(&augmented_args->__data, size, attr) < 0) + if (bpf_probe_read_user(&augmented_args->__data, size, attr) < 0) goto failure; return augmented__output(args, augmented_args, len + size); @@ -347,7 +347,7 @@ int sys_enter_clock_nanosleep(struct syscall_enter_args *args) if (size > sizeof(augmented_args->__data)) goto failure; - bpf_probe_read(&augmented_args->__data, size, rqtp_arg); + bpf_probe_read_user(&augmented_args->__data, size, rqtp_arg); return augmented__output(args, augmented_args, len + size); failure: @@ -385,7 +385,7 @@ int sys_enter(struct syscall_enter_args *args) if (augmented_args == NULL) return 1; - bpf_probe_read(&augmented_args->args, sizeof(augmented_args->args), args); + bpf_probe_read_kernel(&augmented_args->args, sizeof(augmented_args->args), args); /* * Jump to syscall specific augmenter, even if the default one, @@ -406,7 +406,7 @@ int sys_exit(struct syscall_exit_args *args) if (pid_filter__has(&pids_filtered, getpid())) return 0; - bpf_probe_read(&exit_args, sizeof(exit_args), args); + bpf_probe_read_kernel(&exit_args, sizeof(exit_args), args); /* * Jump to syscall specific return augmenter, even if the default one, * "!raw_syscalls:unaugmented" that will just return 1 to return the -- 2.41.0