From 212b9ab6775b5f340de848b5b6eef6968ccf7f20 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 16 Jul 2019 16:28:14 -0300 Subject: [PATCH] perf augmented_raw_syscalls: Augment sockaddr arg in 'connect' MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We already had a beautifier for an augmented sockaddr payload, but that was when we were hooking on each syscalls:sys_enter_foo tracepoints, since now we're almost doing that by doing a tail call from raw_syscalls:sys_enter, its almost the same, we can reuse it straight away. # perf trace -e connec* ssh www.bla.com connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(4, { .family: PF_LOCAL, path: /var/lib/sss/pipes/nss }, 0x6e) = 0 connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory) connect(5, { .family: PF_INET, port: 53, addr: 192.168.44.1 }, 0x10) = 0 connect(5, { .family: PF_INET, port: 22, addr: 146.112.61.108 }, 0x10) = 0 connect(5, { .family: PF_INET6, port: 22, addr: ::ffff:146.112.61.108 }, 0x1c) = 0 ^C# Cc: Adrian Hunter Cc: Jiri Olsa Cc: Luis Cláudio Gonçalves Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-5xkrbcpjsgnr3zt1aqdd7nvc@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- .../examples/bpf/augmented_raw_syscalls.c | 35 ++++++++++++++++--- 1 file changed, 30 insertions(+), 5 deletions(-) diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c index 77bb6a0edce3..d7a292d7ee2f 100644 --- a/tools/perf/examples/bpf/augmented_raw_syscalls.c +++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c @@ -16,6 +16,7 @@ #include #include +#include #include /* bpf-output associated map */ @@ -69,10 +70,13 @@ pid_filter(pids_filtered); struct augmented_args_payload { struct syscall_enter_args args; - struct { - struct augmented_filename filename; - struct augmented_filename filename2; - }; + union { + struct { + struct augmented_filename filename, + filename2; + }; + struct sockaddr_storage saddr; + }; }; bpf_map(augmented_args_tmp, PERCPU_ARRAY, int, struct augmented_args_payload, 1); @@ -112,11 +116,32 @@ int syscall_unaugmented(struct syscall_enter_args *args) } /* - * This will be tail_called from SEC("raw_syscalls:sys_enter"), so will find in + * These will be tail_called from SEC("raw_syscalls:sys_enter"), so will find in * augmented_args_tmp what was read by that raw_syscalls:sys_enter and go * on from there, reading the first syscall arg as a string, i.e. open's * filename. */ +SEC("!syscalls:sys_enter_connect") +int sys_enter_connect(struct syscall_enter_args *args) +{ + int key = 0; + struct augmented_args_payload *augmented_args = bpf_map_lookup_elem(&augmented_args_tmp, &key); + const void *sockaddr_arg = (const void *)args->args[1]; + unsigned int socklen = args->args[2]; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + if (socklen > sizeof(augmented_args->saddr)) + socklen = sizeof(augmented_args->saddr); + + probe_read(&augmented_args->saddr, socklen, sockaddr_arg); + + /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */ + return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len + socklen); +} + SEC("!syscalls:sys_enter_open") int sys_enter_open(struct syscall_enter_args *args) {