From 74fc8801edc279fb5f778eb91df48e4d3cd951a2 Mon Sep 17 00:00:00 2001 From: Kui-Feng Lee Date: Fri, 21 Apr 2023 14:41:31 -0700 Subject: bpftool: Show map IDs along with struct_ops links. A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach struct_ops to links. (226bc6ae6405) It would be helpful for users to know which map is associated with the link. The assumption was that every link is associated with a BPF program, but this does not hold true for struct_ops. It would be better to display map_id instead of prog_id for struct_ops links. However, some tools may rely on the old assumption and need a prog_id. The discussion on the mailing list suggests that tools should parse JSON format. We will maintain the existing JSON format by adding a map_id without removing prog_id. As for plain text format, we will remove prog_id from the header line and add a map_id for struct_ops links. Signed-off-by: Kui-Feng Lee Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20230421214131.352662-1-kuifeng@meta.com --- tools/bpf/bpftool/link.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index d98dbc50cf4c..243b74e18e51 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -212,7 +212,10 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) case BPF_LINK_TYPE_NETFILTER: netfilter_dump_json(info, json_wtr); break; - + case BPF_LINK_TYPE_STRUCT_OPS: + jsonw_uint_field(json_wtr, "map_id", + info->struct_ops.map_id); + break; default: break; } @@ -245,7 +248,10 @@ static void show_link_header_plain(struct bpf_link_info *info) else printf("type %u ", info->type); - printf("prog %u ", info->prog_id); + if (info->type == BPF_LINK_TYPE_STRUCT_OPS) + printf("map %u ", info->struct_ops.map_id); + else + printf("prog %u ", info->prog_id); } static void show_link_attach_type_plain(__u32 attach_type) -- cgit v1.2.3-70-g09d2 From bf06c9393493a2862d4670beda2928423c774ff3 Mon Sep 17 00:00:00 2001 From: Xueming Feng Date: Thu, 27 Apr 2023 20:03:13 +0800 Subject: bpftool: Dump map id instead of value for map_of_maps types When using `bpftool map dump` with map_of_maps, it is usually more convenient to show the inner map id instead of raw value. We are changing the plain print behavior to show inner_map_id instead of hex value, this would help with quick look up of inner map with `bpftool map dump id `. To avoid disrupting scripted behavior, we will add a new `inner_map_id` field to json output instead of replacing value. plain print: ``` $ bpftool map dump id 138 Without Patch: key: fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 05 27 16 06 00 value: 8b 00 00 00 Found 1 element With Patch: key: fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 05 27 16 06 00 inner_map_id: 139 Found 1 element ``` json print: ``` $ bpftool -p map dump id 567 Without Patch: [{ "key": ["0xc0","0x00","0x02","0x05","0x27","0x16","0x06","0x00" ], "value": ["0x38","0x02","0x00","0x00" ] } ] With Patch: [{ "key": ["0xc0","0x00","0x02","0x05","0x27","0x16","0x06","0x00" ], "value": ["0x38","0x02","0x00","0x00" ], "inner_map_id": 568 } ] ``` Signed-off-by: Xueming Feng Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20230427120313.43574-1-kuro@kuroa.me Signed-off-by: Martin KaFai Lau --- tools/bpf/bpftool/map.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index aaeb8939e137..ae9e822aa3fe 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -139,6 +139,9 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key, print_hex_data_json(key, info->key_size); jsonw_name(json_wtr, "value"); print_hex_data_json(value, info->value_size); + if (map_is_map_of_maps(info->type)) + jsonw_uint_field(json_wtr, "inner_map_id", + *(unsigned int *)value); if (btf) { struct btf_dumper d = { .btf = btf, @@ -259,8 +262,13 @@ static void print_entry_plain(struct bpf_map_info *info, unsigned char *key, } if (info->value_size) { - printf("value:%c", break_names ? '\n' : ' '); - fprint_hex(stdout, value, info->value_size, " "); + if (map_is_map_of_maps(info->type)) { + printf("inner_map_id:%c", break_names ? '\n' : ' '); + printf("%u ", *(unsigned int *)value); + } else { + printf("value:%c", break_names ? '\n' : ' '); + fprint_hex(stdout, value, info->value_size, " "); + } } printf("\n"); -- cgit v1.2.3-70-g09d2 From 04cb8453a91c7c22f60ddadb6cef0d19abb33bb5 Mon Sep 17 00:00:00 2001 From: Alan Maguire Date: Fri, 12 May 2023 12:31:34 +0100 Subject: bpftool: JIT limited misreported as negative value on aarch64 On aarch64, "bpftool feature" reports an incorrect BPF JIT limit: $ sudo /sbin/bpftool feature Scanning system configuration... bpf() syscall restricted to privileged users JIT compiler is enabled JIT compiler hardening is disabled JIT compiler kallsyms exports are enabled for root skipping kernel config, can't open file: No such file or directory Global memory limit for JIT compiler for unprivileged users is -201326592 bytes This is because /proc/sys/net/core/bpf_jit_limit reports $ sudo cat /proc/sys/net/core/bpf_jit_limit 68169519595520 ...and an int is assumed in read_procfs(). Change read_procfs() to return a long to avoid negative value reporting. Fixes: 7a4522bbef0c ("tools: bpftool: add probes for /proc/ eBPF parameters") Reported-by: Nicky Veitch Signed-off-by: Alan Maguire Signed-off-by: Daniel Borkmann Acked-by: Jiri Olsa Acked-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20230512113134.58996-1-alan.maguire@oracle.com --- tools/bpf/bpftool/feature.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index da16e6a27ccc..0675d6a46413 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -167,12 +167,12 @@ static int get_vendor_id(int ifindex) return strtol(buf, NULL, 0); } -static int read_procfs(const char *path) +static long read_procfs(const char *path) { char *endptr, *line = NULL; size_t len = 0; FILE *fd; - int res; + long res; fd = fopen(path, "r"); if (!fd) @@ -194,7 +194,7 @@ static int read_procfs(const char *path) static void probe_unprivileged_disabled(void) { - int res; + long res; /* No support for C-style ouptut */ @@ -216,14 +216,14 @@ static void probe_unprivileged_disabled(void) printf("Unable to retrieve required privileges for bpf() syscall\n"); break; default: - printf("bpf() syscall restriction has unknown value %d\n", res); + printf("bpf() syscall restriction has unknown value %ld\n", res); } } } static void probe_jit_enable(void) { - int res; + long res; /* No support for C-style ouptut */ @@ -245,7 +245,7 @@ static void probe_jit_enable(void) printf("Unable to retrieve JIT-compiler status\n"); break; default: - printf("JIT-compiler status has unknown value %d\n", + printf("JIT-compiler status has unknown value %ld\n", res); } } @@ -253,7 +253,7 @@ static void probe_jit_enable(void) static void probe_jit_harden(void) { - int res; + long res; /* No support for C-style ouptut */ @@ -275,7 +275,7 @@ static void probe_jit_harden(void) printf("Unable to retrieve JIT hardening status\n"); break; default: - printf("JIT hardening status has unknown value %d\n", + printf("JIT hardening status has unknown value %ld\n", res); } } @@ -283,7 +283,7 @@ static void probe_jit_harden(void) static void probe_jit_kallsyms(void) { - int res; + long res; /* No support for C-style ouptut */ @@ -302,14 +302,14 @@ static void probe_jit_kallsyms(void) printf("Unable to retrieve JIT kallsyms export status\n"); break; default: - printf("JIT kallsyms exports status has unknown value %d\n", res); + printf("JIT kallsyms exports status has unknown value %ld\n", res); } } } static void probe_jit_limit(void) { - int res; + long res; /* No support for C-style ouptut */ @@ -322,7 +322,7 @@ static void probe_jit_limit(void) printf("Unable to retrieve global memory limit for JIT compiler for unprivileged users\n"); break; default: - printf("Global memory limit for JIT compiler for unprivileged users is %d bytes\n", res); + printf("Global memory limit for JIT compiler for unprivileged users is %ld bytes\n", res); } } } -- cgit v1.2.3-70-g09d2