diff options
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 115 |
1 files changed, 76 insertions, 39 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index d8d5f18a141a..a8420e6abb56 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -9,19 +9,19 @@ #include <linux/bpf-cgroup.h> #include <linux/cleanup.h> -#include <linux/security.h> +#include <linux/error-injection.h> #include <linux/module.h> -#include <linux/uaccess.h> #include <linux/rculist.h> -#include <linux/error-injection.h> +#include <linux/security.h> +#include <linux/uaccess.h> #include <asm/setup.h> /* for COMMAND_LINE_SIZE */ #include "trace_dynevent.h" #include "trace_kprobe_selftest.h" #include "trace_probe.h" -#include "trace_probe_tmpl.h" #include "trace_probe_kernel.h" +#include "trace_probe_tmpl.h" #define KPROBE_EVENT_SYSTEM "kprobes" #define KRETPROBE_MAXACTIVE_MAX 4096 @@ -31,7 +31,8 @@ static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata; static int __init set_kprobe_boot_events(char *str) { - strscpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE); + trace_append_boot_param(kprobe_boot_events_buf, str, ';', + COMMAND_LINE_SIZE); disable_tracing_selftest("running kprobe events"); return 1; @@ -82,6 +83,7 @@ static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev) #define for_each_trace_kprobe(pos, dpos) \ for_each_dyn_event(dpos) \ if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos))) +#define trace_kprobe_list_empty() list_empty(&dyn_event_list) static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) { @@ -124,9 +126,8 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) if (!p) return true; *p = '\0'; - rcu_read_lock_sched(); - ret = !!find_module(tk->symbol); - rcu_read_unlock_sched(); + scoped_guard(rcu) + ret = !!find_module(tk->symbol); *p = ':'; return ret; @@ -275,7 +276,7 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group, struct trace_kprobe *tk __free(free_trace_kprobe) = NULL; int ret = -ENOMEM; - tk = kzalloc(struct_size(tk, tp.args, nargs), GFP_KERNEL); + tk = kzalloc_flex(*tk, tp.args, nargs); if (!tk) return ERR_PTR(ret); @@ -765,6 +766,14 @@ static unsigned int number_of_same_symbols(const char *mod, const char *func_nam if (!mod) kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count); + /* + * If the symbol is found in vmlinux, use vmlinux resolution only. + * This prevents module symbols from shadowing vmlinux symbols + * and causing -EADDRNOTAVAIL for unqualified kprobe targets. + */ + if (!mod && ctx.count > 0) + return ctx.count; + module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx); return ctx.count; @@ -796,12 +805,10 @@ static struct module *try_module_get_by_name(const char *name) { struct module *mod; - rcu_read_lock_sched(); + guard(rcu)(); mod = find_module(name); if (mod && !try_module_get(mod)) mod = NULL; - rcu_read_unlock_sched(); - return mod; } #else @@ -864,20 +871,20 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], * FETCHARG:TYPE : use TYPE instead of unsigned long. */ struct trace_kprobe *tk __free(free_trace_kprobe) = NULL; + const char *event = NULL, *group = KPROBE_EVENT_SYSTEM; + const char **new_argv __free(kfree) = NULL; int i, len, new_argc = 0, ret = 0; - bool is_return = false; char *symbol __free(kfree) = NULL; - char *tmp = NULL; - const char **new_argv __free(kfree) = NULL; - const char *event = NULL, *group = KPROBE_EVENT_SYSTEM; + char *ebuf __free(kfree) = NULL; + char *gbuf __free(kfree) = NULL; + char *abuf __free(kfree) = NULL; + char *dbuf __free(kfree) = NULL; enum probe_print_type ptype; + bool is_return = false; int maxactive = 0; - long offset = 0; void *addr = NULL; - char buf[MAX_EVENT_NAME_LEN]; - char gbuf[MAX_EVENT_NAME_LEN]; - char abuf[MAX_BTF_ARGS_LEN]; - char *dbuf __free(kfree) = NULL; + char *tmp = NULL; + long offset = 0; switch (argv[0][0]) { case 'r': @@ -896,6 +903,8 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], event++; if (isdigit(argv[0][1])) { + char *buf __free(kfree) = NULL; + if (!is_return) { trace_probe_log_err(1, BAD_MAXACT_TYPE); return -EINVAL; @@ -908,7 +917,9 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], trace_probe_log_err(1, BAD_MAXACT); return -EINVAL; } - memcpy(buf, &argv[0][1], len); + buf = kmemdup(&argv[0][1], len + 1, GFP_KERNEL); + if (!buf) + return -ENOMEM; buf[len] = '\0'; ret = kstrtouint(buf, 0, &maxactive); if (ret || !maxactive) { @@ -976,6 +987,9 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], trace_probe_log_set_index(0); if (event) { + gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!gbuf) + return -ENOMEM; ret = traceprobe_parse_event_name(&event, &group, gbuf, event - argv[0]); if (ret) @@ -984,16 +998,22 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], if (!event) { /* Make a new event name */ + ebuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!ebuf) + return -ENOMEM; if (symbol) - snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", + snprintf(ebuf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", is_return ? 'r' : 'p', symbol, offset); else - snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", + snprintf(ebuf, MAX_EVENT_NAME_LEN, "%c_0x%p", is_return ? 'r' : 'p', addr); - sanitize_event_name(buf); - event = buf; + sanitize_event_name(ebuf); + event = ebuf; } + abuf = kmalloc(MAX_BTF_ARGS_LEN, GFP_KERNEL); + if (!abuf) + return -ENOMEM; argc -= 2; argv += 2; ctx->funcname = symbol; new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc, @@ -1007,8 +1027,11 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], argc = new_argc; argv = new_argv; } - if (argc > MAX_TRACE_ARGS) + if (argc > MAX_TRACE_ARGS) { + trace_probe_log_set_index(2); + trace_probe_log_err(0, TOO_MANY_ARGS); return -E2BIG; + } ret = traceprobe_expand_dentry_args(argc, argv, &dbuf); if (ret) @@ -1065,14 +1088,18 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], static int trace_kprobe_create_cb(int argc, const char *argv[]) { - struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL }; + struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL; int ret; + ctx = kzalloc_obj(*ctx); + if (!ctx) + return -ENOMEM; + ctx->flags = TPARG_FL_KERNEL; + trace_probe_log_init("trace_kprobe", argc, argv); - ret = trace_kprobe_create_internal(argc, argv, &ctx); + ret = trace_kprobe_create_internal(argc, argv, ctx); - traceprobe_finish_parse(&ctx); trace_probe_log_clear(); return ret; } @@ -1089,7 +1116,7 @@ static int create_or_delete_trace_kprobe(const char *raw_command) if (raw_command[0] == '-') return dyn_event_release(raw_command, &trace_kprobe_ops); - ret = trace_kprobe_create(raw_command); + ret = dyn_event_create(raw_command, &trace_kprobe_ops); return ret == -ECANCELED ? -EINVAL : ret; } @@ -1567,7 +1594,7 @@ print_kprobe_event(struct trace_iterator *iter, int flags, trace_seq_printf(s, "%s: (", trace_probe_name(tp)); - if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) + if (!seq_print_ip_sym_offset(s, field->ip, flags)) goto out; trace_seq_putc(s, ')'); @@ -1597,12 +1624,12 @@ print_kretprobe_event(struct trace_iterator *iter, int flags, trace_seq_printf(s, "%s: (", trace_probe_name(tp)); - if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) + if (!seq_print_ip_sym_offset(s, field->ret_ip, flags)) goto out; trace_seq_puts(s, " <- "); - if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) + if (!seq_print_ip_sym_no_offset(s, field->func, flags)) goto out; trace_seq_putc(s, ')'); @@ -1798,14 +1825,15 @@ static int kprobe_register(struct trace_event_call *event, static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) { struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); + unsigned int flags = trace_probe_load_flag(&tk->tp); int ret = 0; raw_cpu_inc(*tk->nhit); - if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) + if (flags & TP_FLAG_TRACE) kprobe_trace_func(tk, regs); #ifdef CONFIG_PERF_EVENTS - if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) + if (flags & TP_FLAG_PROFILE) ret = kprobe_perf_func(tk, regs); #endif return ret; @@ -1817,6 +1845,7 @@ kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) { struct kretprobe *rp = get_kretprobe(ri); struct trace_kprobe *tk; + unsigned int flags; /* * There is a small chance that get_kretprobe(ri) returns NULL when @@ -1829,10 +1858,11 @@ kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) tk = container_of(rp, struct trace_kprobe, rp); raw_cpu_inc(*tk->nhit); - if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) + flags = trace_probe_load_flag(&tk->tp); + if (flags & TP_FLAG_TRACE) kretprobe_trace_func(tk, ri, regs); #ifdef CONFIG_PERF_EVENTS - if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) + if (flags & TP_FLAG_PROFILE) kretprobe_perf_func(tk, ri, regs); #endif return 0; /* We don't tweak kernel, so just return 0 */ @@ -1962,6 +1992,9 @@ static __init void enable_boot_kprobe_events(void) struct trace_kprobe *tk; struct dyn_event *pos; + if (trace_kprobe_list_empty()) + return; + guard(mutex)(&event_mutex); for_each_trace_kprobe(tk, pos) { list_for_each_entry(file, &tr->events, list) @@ -2028,6 +2061,10 @@ static __init int init_kprobe_trace(void) trace_create_file("kprobe_profile", TRACE_MODE_READ, NULL, NULL, &kprobe_profile_ops); + /* If no 'kprobe_event=' cmd is provided, return directly. */ + if (kprobe_boot_events_buf[0] == '\0') + return 0; + setup_boot_kprobe_events(); return 0; @@ -2059,7 +2096,7 @@ static __init int kprobe_trace_self_tests_init(void) struct trace_kprobe *tk; struct trace_event_file *file; - if (tracing_is_disabled()) + if (unlikely(tracing_disabled)) return -ENODEV; if (tracing_selftest_disabled) |