diff options
23 files changed, 1320 insertions, 92 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 11ab51646d96..655ea596b597 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -23367,6 +23367,19 @@ F: drivers/mtd/ubi/ F: include/linux/mtd/ubi.h F: include/uapi/mtd/ubi-user.h +UPROBES +M: Masami Hiramatsu <mhiramat@kernel.org> +M: Oleg Nesterov <oleg@redhat.com> +M: Peter Zijlstra <peterz@infradead.org> +L: linux-kernel@vger.kernel.org +L: linux-trace-kernel@vger.kernel.org +S: Maintained +F: arch/*/include/asm/uprobes.h +F: arch/*/kernel/probes/uprobes.c +F: arch/*/kernel/uprobes.c +F: include/linux/uprobes.h +F: kernel/events/uprobes.c + USB "USBNET" DRIVER FRAMEWORK M: Oliver Neukum <oneukum@suse.com> L: netdev@vger.kernel.org diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 097e5a18db52..83073fa3c989 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -385,6 +385,7 @@ 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules 462 common mseal sys_mseal +467 common uretprobe sys_uretprobe # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/x86/include/asm/shstk.h b/arch/x86/include/asm/shstk.h index 42fee8959df7..4cb77e004615 100644 --- a/arch/x86/include/asm/shstk.h +++ b/arch/x86/include/asm/shstk.h @@ -21,6 +21,8 @@ unsigned long shstk_alloc_thread_stack(struct task_struct *p, unsigned long clon void shstk_free(struct task_struct *p); int setup_signal_shadow_stack(struct ksignal *ksig); int restore_signal_shadow_stack(void); +int shstk_update_last_frame(unsigned long val); +bool shstk_is_enabled(void); #else static inline long shstk_prctl(struct task_struct *task, int option, unsigned long arg2) { return -EINVAL; } @@ -31,6 +33,8 @@ static inline unsigned long shstk_alloc_thread_stack(struct task_struct *p, static inline void shstk_free(struct task_struct *p) {} static inline int setup_signal_shadow_stack(struct ksignal *ksig) { return 0; } static inline int restore_signal_shadow_stack(void) { return 0; } +static inline int shstk_update_last_frame(unsigned long val) { return 0; } +static inline bool shstk_is_enabled(void) { return false; } #endif /* CONFIG_X86_USER_SHADOW_STACK */ #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/kernel/shstk.c b/arch/x86/kernel/shstk.c index 6f1e9883f074..059685612362 100644 --- a/arch/x86/kernel/shstk.c +++ b/arch/x86/kernel/shstk.c @@ -577,3 +577,19 @@ long shstk_prctl(struct task_struct *task, int option, unsigned long arg2) return wrss_control(true); return -EINVAL; } + +int shstk_update_last_frame(unsigned long val) +{ + unsigned long ssp; + + if (!features_enabled(ARCH_SHSTK_SHSTK)) + return 0; + + ssp = get_user_shstk_addr(); + return write_user_shstk_64((u64 __user *)ssp, (u64)val); +} + +bool shstk_is_enabled(void) +{ + return features_enabled(ARCH_SHSTK_SHSTK); +} diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index 6c07f6daaa22..5a952c5ea66b 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -12,6 +12,7 @@ #include <linux/ptrace.h> #include <linux/uprobes.h> #include <linux/uaccess.h> +#include <linux/syscalls.h> #include <linux/kdebug.h> #include <asm/processor.h> @@ -308,6 +309,122 @@ static int uprobe_init_insn(struct arch_uprobe *auprobe, struct insn *insn, bool } #ifdef CONFIG_X86_64 + +asm ( + ".pushsection .rodata\n" + ".global uretprobe_trampoline_entry\n" + "uretprobe_trampoline_entry:\n" + "pushq %rax\n" + "pushq %rcx\n" + "pushq %r11\n" + "movq $" __stringify(__NR_uretprobe) ", %rax\n" + "syscall\n" + ".global uretprobe_syscall_check\n" + "uretprobe_syscall_check:\n" + "popq %r11\n" + "popq %rcx\n" + + /* The uretprobe syscall replaces stored %rax value with final + * return address, so we don't restore %rax in here and just + * call ret. + */ + "retq\n" + ".global uretprobe_trampoline_end\n" + "uretprobe_trampoline_end:\n" + ".popsection\n" +); + +extern u8 uretprobe_trampoline_entry[]; +extern u8 uretprobe_trampoline_end[]; +extern u8 uretprobe_syscall_check[]; + +void *arch_uprobe_trampoline(unsigned long *psize) +{ + static uprobe_opcode_t insn = UPROBE_SWBP_INSN; + struct pt_regs *regs = task_pt_regs(current); + + /* + * At the moment the uretprobe syscall trampoline is supported + * only for native 64-bit process, the compat process still uses + * standard breakpoint. + */ + if (user_64bit_mode(regs)) { + *psize = uretprobe_trampoline_end - uretprobe_trampoline_entry; + return uretprobe_trampoline_entry; + } + + *psize = UPROBE_SWBP_INSN_SIZE; + return &insn; +} + +static unsigned long trampoline_check_ip(void) +{ + unsigned long tramp = uprobe_get_trampoline_vaddr(); + + return tramp + (uretprobe_syscall_check - uretprobe_trampoline_entry); +} + +SYSCALL_DEFINE0(uretprobe) +{ + struct pt_regs *regs = task_pt_regs(current); + unsigned long err, ip, sp, r11_cx_ax[3]; + + if (regs->ip != trampoline_check_ip()) + goto sigill; + + err = copy_from_user(r11_cx_ax, (void __user *)regs->sp, sizeof(r11_cx_ax)); + if (err) + goto sigill; + + /* expose the "right" values of r11/cx/ax/sp to uprobe_consumer/s */ + regs->r11 = r11_cx_ax[0]; + regs->cx = r11_cx_ax[1]; + regs->ax = r11_cx_ax[2]; + regs->sp += sizeof(r11_cx_ax); + regs->orig_ax = -1; + + ip = regs->ip; + sp = regs->sp; + + uprobe_handle_trampoline(regs); + + /* + * Some of the uprobe consumers has changed sp, we can do nothing, + * just return via iret. + * .. or shadow stack is enabled, in which case we need to skip + * return through the user space stack address. + */ + if (regs->sp != sp || shstk_is_enabled()) + return regs->ax; + regs->sp -= sizeof(r11_cx_ax); + + /* for the case uprobe_consumer has changed r11/cx */ + r11_cx_ax[0] = regs->r11; + r11_cx_ax[1] = regs->cx; + + /* + * ax register is passed through as return value, so we can use + * its space on stack for ip value and jump to it through the + * trampoline's ret instruction + */ + r11_cx_ax[2] = regs->ip; + regs->ip = ip; + + err = copy_to_user((void __user *)regs->sp, r11_cx_ax, sizeof(r11_cx_ax)); + if (err) + goto sigill; + + /* ensure sysret, see do_syscall_64() */ + regs->r11 = regs->flags; + regs->cx = regs->ip; + + return regs->ax; + +sigill: + force_sig(SIGILL); + return -1; +} + /* * If arch_uprobe->insn doesn't use rip-relative addressing, return * immediately. Otherwise, rewrite the instruction so that it accesses @@ -1076,8 +1193,13 @@ arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs return orig_ret_vaddr; nleft = copy_to_user((void __user *)regs->sp, &trampoline_vaddr, rasize); - if (likely(!nleft)) + if (likely(!nleft)) { + if (shstk_update_last_frame(trampoline_vaddr)) { + force_sig(SIGSEGV); + return -1; + } return orig_ret_vaddr; + } if (nleft != rasize) { pr_err("return address clobbered: pid=%d, %%sp=%#lx, %%ip=%#lx\n", diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index fff820c3e93e..4bcf6754738d 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -979,6 +979,8 @@ asmlinkage long sys_lsm_list_modules(u64 __user *ids, u32 __user *size, u32 flag /* x86 */ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int on); +asmlinkage long sys_uretprobe(void); + /* pciconfig: alpha, arm, arm64, ia64, sparc */ asmlinkage long sys_pciconfig_read(unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len, diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index f46e0ca0169c..b503fafb7fb3 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -138,6 +138,9 @@ extern bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check c extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs); extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr, void *src, unsigned long len); +extern void uprobe_handle_trampoline(struct pt_regs *regs); +extern void *arch_uprobe_trampoline(unsigned long *psize); +extern unsigned long uprobe_get_trampoline_vaddr(void); #else /* !CONFIG_UPROBES */ struct uprobes_state { }; diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 5bf6148cac2b..985a262d0f9e 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -841,8 +841,11 @@ __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules) #define __NR_mseal 462 __SYSCALL(__NR_mseal, sys_mseal) +#define __NR_uretprobe 463 +__SYSCALL(__NR_uretprobe, sys_uretprobe) + #undef __NR_syscalls -#define __NR_syscalls 463 +#define __NR_syscalls 464 /* * 32 bit systems traditionally used different diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index ad57944b6c40..8d57255e5b29 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -11,6 +11,7 @@ #include <linux/perf_event.h> #include <linux/slab.h> #include <linux/sched/task_stack.h> +#include <linux/uprobes.h> #include "internal.h" @@ -176,13 +177,51 @@ put_callchain_entry(int rctx) put_recursion_context(this_cpu_ptr(callchain_recursion), rctx); } +static void fixup_uretprobe_trampoline_entries(struct perf_callchain_entry *entry, + int start_entry_idx) +{ +#ifdef CONFIG_UPROBES + struct uprobe_task *utask = current->utask; + struct return_instance *ri; + __u64 *cur_ip, *last_ip, tramp_addr; + + if (likely(!utask || !utask->return_instances)) + return; + + cur_ip = &entry->ip[start_entry_idx]; + last_ip = &entry->ip[entry->nr - 1]; + ri = utask->return_instances; + tramp_addr = uprobe_get_trampoline_vaddr(); + + /* + * If there are pending uretprobes for the current thread, they are + * recorded in a list inside utask->return_instances; each such + * pending uretprobe replaces traced user function's return address on + * the stack, so when stack trace is captured, instead of seeing + * actual function's return address, we'll have one or many uretprobe + * trampoline addresses in the stack trace, which are not helpful and + * misleading to users. + * So here we go over the pending list of uretprobes, and each + * encountered trampoline address is replaced with actual return + * address. + */ + while (ri && cur_ip <= last_ip) { + if (*cur_ip == tramp_addr) { + *cur_ip = ri->orig_ret_vaddr; + ri = ri->next; + } + cur_ip++; + } +#endif +} + struct perf_callchain_entry * get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, u32 max_stack, bool crosstask, bool add_mark) { struct perf_callchain_entry *entry; struct perf_callchain_entry_ctx ctx; - int rctx; + int rctx, start_entry_idx; entry = get_callchain_entry(&rctx); if (!entry) @@ -215,7 +254,9 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, if (add_mark) perf_callchain_store_context(&ctx, PERF_CONTEXT_USER); + start_entry_idx = entry->nr; perf_callchain_user(&ctx, regs); + fixup_uretprobe_trampoline_entries(entry, start_entry_idx); } } diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 2c83ba776fc7..99be2adedbc0 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1474,11 +1474,20 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area) return ret; } +void * __weak arch_uprobe_trampoline(unsigned long *psize) +{ + static uprobe_opcode_t insn = UPROBE_SWBP_INSN; + + *psize = UPROBE_SWBP_INSN_SIZE; + return &insn; +} + static struct xol_area *__create_xol_area(unsigned long vaddr) { struct mm_struct *mm = current->mm; - uprobe_opcode_t insn = UPROBE_SWBP_INSN; + unsigned long insns_size; struct xol_area *area; + void *insns; area = kmalloc(sizeof(*area), GFP_KERNEL); if (unlikely(!area)) @@ -1502,7 +1511,8 @@ static struct xol_area *__create_xol_area(unsigned long vaddr) /* Reserve the 1st slot for get_trampoline_vaddr() */ set_bit(0, area->bitmap); atomic_set(&area->slot_count, 1); - arch_uprobe_copy_ixol(area->pages[0], 0, &insn, UPROBE_SWBP_INSN_SIZE); + insns = arch_uprobe_trampoline(&insns_size); + arch_uprobe_copy_ixol(area->pages[0], 0, insns, insns_size); if (!xol_add_vma(mm, area)) return area; @@ -1827,7 +1837,7 @@ void uprobe_copy_process(struct task_struct *t, unsigned long flags) * * Returns -1 in case the xol_area is not allocated. */ -static unsigned long get_trampoline_vaddr(void) +unsigned long uprobe_get_trampoline_vaddr(void) { struct xol_area *area; unsigned long trampoline_vaddr = -1; @@ -1878,7 +1888,7 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) if (!ri) return; - trampoline_vaddr = get_trampoline_vaddr(); + trampoline_vaddr = uprobe_get_trampoline_vaddr(); orig_ret_vaddr = arch_uretprobe_hijack_return_addr(trampoline_vaddr, regs); if (orig_ret_vaddr == -1) goto fail; @@ -2123,7 +2133,7 @@ static struct return_instance *find_next_ret_chain(struct return_instance *ri) return ri; } -static void handle_trampoline(struct pt_regs *regs) +void uprobe_handle_trampoline(struct pt_regs *regs) { struct uprobe_task *utask; struct return_instance *ri, *next; @@ -2149,6 +2159,15 @@ static void handle_trampoline(struct pt_regs *regs) instruction_pointer_set(regs, ri->orig_ret_vaddr); do { + /* pop current instance from the stack of pending return instances, + * as it's not pending anymore: we just fixed up original + * instruction pointer in regs and are about to call handlers; + * this allows fixup_uretprobe_trampoline_entries() to properly fix up + * captured stack traces from uretprobe handlers, in which pending + * trampoline addresses on the stack are replaced with correct + * original return addresses + */ + utask->return_instances = ri->next; if (valid) handle_uretprobe_chain(ri, regs); ri = free_ret_instance(ri); @@ -2187,8 +2206,8 @@ static void handle_swbp(struct pt_regs *regs) int is_swbp; bp_vaddr = uprobe_get_swbp_addr(regs); - if (bp_vaddr == get_trampoline_vaddr()) - return handle_trampoline(regs); + if (bp_vaddr == uprobe_get_trampoline_vaddr()) + return uprobe_handle_trampoline(regs); uprobe = find_active_uprobe(bp_vaddr, &is_swbp); if (!uprobe) { diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 2ef820a2d067..c00a86931f8c 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -390,3 +390,5 @@ COND_SYSCALL(setuid16); /* restartable sequence */ COND_SYSCALL(rseq); + +COND_SYSCALL(uretprobe); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 16383247bdbf..61a6da808203 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -678,6 +678,21 @@ end: } #ifdef CONFIG_MODULES +static int validate_module_probe_symbol(const char *modname, const char *symbol); + +static int register_module_trace_kprobe(struct module *mod, struct trace_kprobe *tk) +{ + const char *p; + int ret = 0; + + p = strchr(trace_kprobe_symbol(tk), ':'); + if (p) + ret = validate_module_probe_symbol(module_name(mod), p + 1); + if (!ret) + ret = __register_trace_kprobe(tk); + return ret; +} + /* Module notifier call back, checking event on the module */ static int trace_kprobe_module_callback(struct notifier_block *nb, unsigned long val, void *data) @@ -696,7 +711,7 @@ static int trace_kprobe_module_callback(struct notifier_block *nb, if (trace_kprobe_within_module(tk, mod)) { /* Don't need to check busy - this should have gone. */ __unregister_trace_kprobe(tk); - ret = __register_trace_kprobe(tk); + ret = register_module_trace_kprobe(mod, tk); if (ret) pr_warn("Failed to re-register probe %s on %s: %d\n", trace_probe_name(&tk->tp), @@ -747,17 +762,81 @@ static int count_mod_symbols(void *data, const char *name, unsigned long unused) return 0; } -static unsigned int number_of_same_symbols(char *func_name) +static unsigned int number_of_same_symbols(const char *mod, const char *func_name) { struct sym_count_ctx ctx = { .count = 0, .name = func_name }; - kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count); + if (!mod) + kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count); - module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx); + module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx); return ctx.count; } +static int validate_module_probe_symbol(const char *modname, const char *symbol) +{ + unsigned int count = number_of_same_symbols(modname, symbol); + + if (count > 1) { + /* + * Users should use ADDR to remove the ambiguity of + * using KSYM only. + */ + return -EADDRNOTAVAIL; + } else if (count == 0) { + /* + * We can return ENOENT earlier than when register the + * kprobe. + */ + return -ENOENT; + } + return 0; +} + +#ifdef CONFIG_MODULES +/* Return NULL if the module is not loaded or under unloading. */ +static struct module *try_module_get_by_name(const char *name) +{ + struct module *mod; + + rcu_read_lock_sched(); + mod = find_module(name); + if (mod && !try_module_get(mod)) + mod = NULL; + rcu_read_unlock_sched(); + + return mod; +} +#else +#define try_module_get_by_name(name) (NULL) +#endif + +static int validate_probe_symbol(char *symbol) +{ + struct module *mod = NULL; + char *modname = NULL, *p; + int ret = 0; + + p = strchr(symbol, ':'); + if (p) { + modname = symbol; + symbol = p + 1; + *p = '\0'; + mod = try_module_get_by_name(modname); + if (!mod) + goto out; + } + + ret = validate_module_probe_symbol(modname, symbol); +out: + if (p) + *p = ':'; + if (mod) + module_put(mod); + return ret; +} + static int trace_kprobe_entry_handler(struct kretprobe_instance *ri, struct pt_regs *regs); @@ -881,6 +960,14 @@ static int __trace_kprobe_create(int argc, const char *argv[]) trace_probe_log_err(0, BAD_PROBE_ADDR); goto parse_error; } + ret = validate_probe_symbol(symbol); + if (ret) { + if (ret == -EADDRNOTAVAIL) + trace_probe_log_err(0, NON_UNIQ_SYMBOL); + else + trace_probe_log_err(0, BAD_PROBE_ADDR); + goto parse_error; + } if (is_return) ctx.flags |= TPARG_FL_RETURN; ret = kprobe_on_func_entry(NULL, symbol, offset); @@ -893,31 +980,6 @@ static int __trace_kprobe_create(int argc, const char *argv[]) } } - if (symbol && !strchr(symbol, ':')) { - unsigned int count; - - count = number_of_same_symbols(symbol); - if (count > 1) { - /* - * Users should use ADDR to remove the ambiguity of - * using KSYM only. - */ - trace_probe_log_err(0, NON_UNIQ_SYMBOL); - ret = -EADDRNOTAVAIL; - - goto error; - } else if (count == 0) { - /* - * We can return ENOENT earlier than when register the - * kprobe. - */ - trace_probe_log_err(0, BAD_PROBE_ADDR); - ret = -ENOENT; - - goto error; - } - } - trace_probe_log_set_index(0); if (event) { ret = traceprobe_parse_event_name(&event, &group, gbuf, @@ -1835,21 +1897,9 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, char *event; if (func) { - unsigned int count; - - count = number_of_same_symbols(func); - if (count > 1) - /* - * Users should use addr to remove the ambiguity of - * using func only. - */ - return ERR_PTR(-EADDRNOTAVAIL); - else if (count == 0) - /* - * We can return ENOENT earlier than when register the - * kprobe. - */ - return ERR_PTR(-ENOENT); + ret = validate_probe_symbol(func); + if (ret) + return ERR_PTR(ret); } /* @@ -2023,19 +2073,16 @@ static __init int kprobe_trace_self_tests_init(void) pr_info("Testing kprobe tracing: "); ret = create_or_delete_trace_kprobe("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)"); - if (WARN_ON_ONCE(ret)) { - pr_warn("error on probing function entry.\n"); + if (WARN_ONCE(ret, "error on probing function entry.")) { warn++; } else { /* Enable trace point */ tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tk == NULL)) { - pr_warn("error on getting new probe.\n"); + if (WARN_ONCE(tk == NULL, "error on probing function entry.")) { warn++; } else { file = find_trace_probe_file(tk, top_trace_array()); - if (WARN_ON_ONCE(file == NULL)) { - pr_warn("error on getting probe file.\n"); + if (WARN_ONCE(file == NULL, "error on getting probe file.")) { warn++; } else enable_trace_kprobe( @@ -2044,19 +2091,16 @@ static __init int kprobe_trace_self_tests_init(void) } ret = create_or_delete_trace_kprobe("r:testprobe2 kprobe_trace_selftest_target $retval"); - if (WARN_ON_ONCE(ret)) { - pr_warn("error on probing function return.\n"); + if (WARN_ONCE(ret, "error on probing function return.")) { warn++; } else { /* Enable trace point */ tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tk == NULL)) { - pr_warn("error on getting 2nd new probe.\n"); + if (WARN_ONCE(tk == NULL, "error on getting 2nd new probe.")) { warn++; } else { file = find_trace_probe_file(tk, top_trace_array()); - if (WARN_ON_ONCE(file == NULL)) { - pr_warn("error on getting probe file.\n"); + if (WARN_ONCE(file == NULL, "error on getting probe file.")) { warn++; } else enable_trace_kprobe( @@ -2079,18 +2123,15 @@ static __init int kprobe_trace_self_tests_init(void) /* Disable trace points before removing it */ tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tk == NULL)) { - pr_warn("error on getting test probe.\n"); + if (WARN_ONCE(tk == NULL, "error on getting test probe.")) { warn++; } else { - if (trace_kprobe_nhit(tk) != 1) { - pr_warn("incorrect number of testprobe hits\n"); + if (WARN_ONCE(trace_kprobe_nhit(tk) != 1, + "incorrect number of testprobe hits.")) warn++; - } file = find_trace_probe_file(tk, top_trace_array()); - if (WARN_ON_ONCE(file == NULL)) { - pr_warn("error on getting probe file.\n"); + if (WARN_ONCE(file == NULL, "error on getting probe file.")) { warn++; } else disable_trace_kprobe( @@ -2098,18 +2139,15 @@ static __init int kprobe_trace_self_tests_init(void) } tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tk == NULL)) { - pr_warn("error on getting 2nd test probe.\n"); + if (WARN_ONCE(tk == NULL, "error on getting 2nd test probe.")) { warn++; } else { - if (trace_kprobe_nhit(tk) != 1) { - pr_warn("incorrect number of testprobe2 hits\n"); + if (WARN_ONCE(trace_kprobe_nhit(tk) != 1, + "incorrect number of testprobe2 hits.")) warn++; - } file = find_trace_probe_file(tk, top_trace_array()); - if (WARN_ON_ONCE(file == NULL)) { - pr_warn("error on getting probe file.\n"); + if (WARN_ONCE(file == NULL, "error on getting probe file.")) { warn++; } else disable_trace_kprobe( @@ -2117,23 +2155,15 @@ static __init int kprobe_trace_self_tests_init(void) } ret = create_or_delete_trace_kprobe("-:testprobe"); - if (WARN_ON_ONCE(ret)) { - pr_warn("error on deleting a probe.\n"); + if (WARN_ONCE(ret, "error on deleting a probe.")) warn++; - } ret = create_or_delete_trace_kprobe("-:testprobe2"); - if (WARN_ON_ONCE(ret)) { - pr_warn("error on deleting a probe.\n"); + if (WARN_ONCE(ret, "error on deleting a probe.")) warn++; - } + end: - ret = dyn_events_release_all(&trace_kprobe_ops); - if (WARN_ON_ONCE(ret)) { - pr_warn("error on cleaning up probes.\n"); - warn++; - } /* * Wait for the optimizer work to finish. Otherwise it might fiddle * with probes in already freed __init text. diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c index 64e715e7ed11..0a50b05add96 100644 --- a/samples/fprobe/fprobe_example.c +++ b/samples/fprobe/fprobe_example.c @@ -150,4 +150,5 @@ static void __exit fprobe_exit(void) module_init(fprobe_init) module_exit(fprobe_exit) +MODULE_DESCRIPTION("sample kernel module showing the use of fprobe"); MODULE_LICENSE("GPL"); diff --git a/samples/kprobes/kprobe_example.c b/samples/kprobes/kprobe_example.c index ef44c614c6d9..53ec6c8b8c40 100644 --- a/samples/kprobes/kprobe_example.c +++ b/samples/kprobes/kprobe_example.c @@ -125,4 +125,5 @@ static void __exit kprobe_exit(void) module_init(kprobe_init) module_exit(kprobe_exit) +MODULE_DESCRIPTION("sample kernel module showing the use of kprobes"); MODULE_LICENSE("GPL"); diff --git a/samples/kprobes/kretprobe_example.c b/samples/kprobes/kretprobe_example.c index ed79fd3d48fb..65d6dcafd742 100644 --- a/samples/kprobes/kretprobe_example.c +++ b/samples/kprobes/kretprobe_example.c @@ -104,4 +104,5 @@ static void __exit kretprobe_exit(void) module_init(kretprobe_init) module_exit(kretprobe_exit) +MODULE_DESCRIPTION("sample kernel module showing the use of return probes"); MODULE_LICENSE("GPL"); diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h index 8a63a9913495..6f7f22ac9da5 100644 --- a/tools/include/linux/compiler.h +++ b/tools/include/linux/compiler.h @@ -62,6 +62,10 @@ #define __nocf_check __attribute__((nocf_check)) #endif +#ifndef __naked +#define __naked __attribute__((__naked__)) +#endif + /* Are two types/vars the same type (ignoring qualifiers)? */ #ifndef __same_type # define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index f8962a1dd397..fd28c1157bd3 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -18,6 +18,7 @@ #include <linux/in6.h> #include <linux/un.h> #include <net/sock.h> +#include <linux/namei.h> #include "bpf_testmod.h" #include "bpf_testmod_kfunc.h" @@ -413,6 +414,119 @@ static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { .write = bpf_testmod_test_write, }; +/* bpf_testmod_uprobe sysfs attribute is so far enabled for x86_64 only, + * please see test_uretprobe_regs_change test + */ +#ifdef __x86_64__ + +static int +uprobe_ret_handler(struct uprobe_consumer *self, unsigned long func, + struct pt_regs *regs) + +{ + regs->ax = 0x12345678deadbeef; + regs->cx = 0x87654321feebdaed; + regs->r11 = (u64) -1; + return true; +} + +struct testmod_uprobe { + struct path path; + loff_t offset; + struct uprobe_consumer consumer; +}; + +static DEFINE_MUTEX(testmod_uprobe_mutex); + +static struct testmod_uprobe uprobe = { + .consumer.ret_handler = uprobe_ret_handler, +}; + +static int testmod_register_uprobe(loff_t offset) +{ + int err = -EBUSY; + + if (uprobe.offset) + return -EBUSY; + + mutex_lock(&testmod_uprobe_mutex); + + if (uprobe.offset) + goto out; + + err = kern_path("/proc/self/exe", LOOKUP_FOLLOW, &uprobe.path); + if (err) + goto out; + + err = uprobe_register_refctr(d_real_inode(uprobe.path.dentry), + offset, 0, &uprobe.consumer); + if (err) + path_put(&uprobe.path); + else + uprobe.offset = offset; + +out: + mutex_unlock(&testmod_uprobe_mutex); + return err; +} + +static void testmod_unregister_uprobe(void) +{ + mutex_lock(&testmod_uprobe_mutex); + + if (uprobe.offset) { + uprobe_unregister(d_real_inode(uprobe.path.dentry), + uprobe.offset, &uprobe.consumer); + uprobe.offset = 0; + } + + mutex_unlock(&testmod_uprobe_mutex); +} + +static ssize_t +bpf_testmod_uprobe_write(struct file *file, struct kobject *kobj,< |