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1664 lines
38 KiB
1664 lines
38 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* uprobes-based tracing events |
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* |
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* Copyright (C) IBM Corporation, 2010-2012 |
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* Author: Srikar Dronamraju <[email protected]> |
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*/ |
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#define pr_fmt(fmt) "trace_uprobe: " fmt |
|
|
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#include <linux/security.h> |
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#include <linux/ctype.h> |
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#include <linux/module.h> |
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#include <linux/uaccess.h> |
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#include <linux/uprobes.h> |
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#include <linux/namei.h> |
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#include <linux/string.h> |
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#include <linux/rculist.h> |
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|
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#include "trace_dynevent.h" |
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#include "trace_probe.h" |
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#include "trace_probe_tmpl.h" |
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|
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#define UPROBE_EVENT_SYSTEM "uprobes" |
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|
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struct uprobe_trace_entry_head { |
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struct trace_entry ent; |
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unsigned long vaddr[]; |
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}; |
|
|
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#define SIZEOF_TRACE_ENTRY(is_return) \ |
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(sizeof(struct uprobe_trace_entry_head) + \ |
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sizeof(unsigned long) * (is_return ? 2 : 1)) |
|
|
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#define DATAOF_TRACE_ENTRY(entry, is_return) \ |
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((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return)) |
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|
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static int trace_uprobe_create(const char *raw_command); |
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static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev); |
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static int trace_uprobe_release(struct dyn_event *ev); |
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static bool trace_uprobe_is_busy(struct dyn_event *ev); |
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static bool trace_uprobe_match(const char *system, const char *event, |
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int argc, const char **argv, struct dyn_event *ev); |
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|
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static struct dyn_event_operations trace_uprobe_ops = { |
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.create = trace_uprobe_create, |
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.show = trace_uprobe_show, |
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.is_busy = trace_uprobe_is_busy, |
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.free = trace_uprobe_release, |
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.match = trace_uprobe_match, |
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}; |
|
|
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/* |
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* uprobe event core functions |
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*/ |
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struct trace_uprobe { |
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struct dyn_event devent; |
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struct uprobe_consumer consumer; |
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struct path path; |
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struct inode *inode; |
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char *filename; |
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unsigned long offset; |
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unsigned long ref_ctr_offset; |
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unsigned long nhit; |
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struct trace_probe tp; |
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}; |
|
|
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static bool is_trace_uprobe(struct dyn_event *ev) |
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{ |
|
return ev->ops == &trace_uprobe_ops; |
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} |
|
|
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static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev) |
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{ |
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return container_of(ev, struct trace_uprobe, devent); |
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} |
|
|
|
/** |
|
* for_each_trace_uprobe - iterate over the trace_uprobe list |
|
* @pos: the struct trace_uprobe * for each entry |
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* @dpos: the struct dyn_event * to use as a loop cursor |
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*/ |
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#define for_each_trace_uprobe(pos, dpos) \ |
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for_each_dyn_event(dpos) \ |
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if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos))) |
|
|
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#define SIZEOF_TRACE_UPROBE(n) \ |
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(offsetof(struct trace_uprobe, tp.args) + \ |
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(sizeof(struct probe_arg) * (n))) |
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|
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static int register_uprobe_event(struct trace_uprobe *tu); |
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static int unregister_uprobe_event(struct trace_uprobe *tu); |
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|
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struct uprobe_dispatch_data { |
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struct trace_uprobe *tu; |
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unsigned long bp_addr; |
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}; |
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|
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static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); |
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static int uretprobe_dispatcher(struct uprobe_consumer *con, |
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unsigned long func, struct pt_regs *regs); |
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|
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#ifdef CONFIG_STACK_GROWSUP |
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static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) |
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{ |
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return addr - (n * sizeof(long)); |
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} |
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#else |
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static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) |
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{ |
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return addr + (n * sizeof(long)); |
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} |
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#endif |
|
|
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static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) |
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{ |
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unsigned long ret; |
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unsigned long addr = user_stack_pointer(regs); |
|
|
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addr = adjust_stack_addr(addr, n); |
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|
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if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret))) |
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return 0; |
|
|
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return ret; |
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} |
|
|
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/* |
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* Uprobes-specific fetch functions |
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*/ |
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static nokprobe_inline int |
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probe_mem_read(void *dest, void *src, size_t size) |
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{ |
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void __user *vaddr = (void __force __user *)src; |
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|
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return copy_from_user(dest, vaddr, size) ? -EFAULT : 0; |
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} |
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|
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static nokprobe_inline int |
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probe_mem_read_user(void *dest, void *src, size_t size) |
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{ |
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return probe_mem_read(dest, src, size); |
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} |
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|
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/* |
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* Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max |
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* length and relative data location. |
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*/ |
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static nokprobe_inline int |
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fetch_store_string(unsigned long addr, void *dest, void *base) |
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{ |
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long ret; |
|
u32 loc = *(u32 *)dest; |
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int maxlen = get_loc_len(loc); |
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u8 *dst = get_loc_data(dest, base); |
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void __user *src = (void __force __user *) addr; |
|
|
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if (unlikely(!maxlen)) |
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return -ENOMEM; |
|
|
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if (addr == FETCH_TOKEN_COMM) |
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ret = strlcpy(dst, current->comm, maxlen); |
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else |
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ret = strncpy_from_user(dst, src, maxlen); |
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if (ret >= 0) { |
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if (ret == maxlen) |
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dst[ret - 1] = '\0'; |
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else |
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/* |
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* Include the terminating null byte. In this case it |
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* was copied by strncpy_from_user but not accounted |
|
* for in ret. |
|
*/ |
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ret++; |
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*(u32 *)dest = make_data_loc(ret, (void *)dst - base); |
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} |
|
|
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return ret; |
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} |
|
|
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static nokprobe_inline int |
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fetch_store_string_user(unsigned long addr, void *dest, void *base) |
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{ |
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return fetch_store_string(addr, dest, base); |
|
} |
|
|
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/* Return the length of string -- including null terminal byte */ |
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static nokprobe_inline int |
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fetch_store_strlen(unsigned long addr) |
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{ |
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int len; |
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void __user *vaddr = (void __force __user *) addr; |
|
|
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if (addr == FETCH_TOKEN_COMM) |
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len = strlen(current->comm) + 1; |
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else |
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len = strnlen_user(vaddr, MAX_STRING_SIZE); |
|
|
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return (len > MAX_STRING_SIZE) ? 0 : len; |
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} |
|
|
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static nokprobe_inline int |
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fetch_store_strlen_user(unsigned long addr) |
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{ |
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return fetch_store_strlen(addr); |
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} |
|
|
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static unsigned long translate_user_vaddr(unsigned long file_offset) |
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{ |
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unsigned long base_addr; |
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struct uprobe_dispatch_data *udd; |
|
|
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udd = (void *) current->utask->vaddr; |
|
|
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base_addr = udd->bp_addr - udd->tu->offset; |
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return base_addr + file_offset; |
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} |
|
|
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/* Note that we don't verify it, since the code does not come from user space */ |
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static int |
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process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, |
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void *base) |
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{ |
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unsigned long val; |
|
|
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/* 1st stage: get value from context */ |
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switch (code->op) { |
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case FETCH_OP_REG: |
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val = regs_get_register(regs, code->param); |
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break; |
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case FETCH_OP_STACK: |
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val = get_user_stack_nth(regs, code->param); |
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break; |
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case FETCH_OP_STACKP: |
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val = user_stack_pointer(regs); |
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break; |
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case FETCH_OP_RETVAL: |
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val = regs_return_value(regs); |
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break; |
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case FETCH_OP_IMM: |
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val = code->immediate; |
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break; |
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case FETCH_OP_COMM: |
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val = FETCH_TOKEN_COMM; |
|
break; |
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case FETCH_OP_DATA: |
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val = (unsigned long)code->data; |
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break; |
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case FETCH_OP_FOFFS: |
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val = translate_user_vaddr(code->immediate); |
|
break; |
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default: |
|
return -EILSEQ; |
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} |
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code++; |
|
|
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return process_fetch_insn_bottom(code, val, dest, base); |
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} |
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NOKPROBE_SYMBOL(process_fetch_insn) |
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|
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static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter) |
|
{ |
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rwlock_init(&filter->rwlock); |
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filter->nr_systemwide = 0; |
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INIT_LIST_HEAD(&filter->perf_events); |
|
} |
|
|
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static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter) |
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{ |
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return !filter->nr_systemwide && list_empty(&filter->perf_events); |
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} |
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|
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static inline bool is_ret_probe(struct trace_uprobe *tu) |
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{ |
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return tu->consumer.ret_handler != NULL; |
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} |
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|
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static bool trace_uprobe_is_busy(struct dyn_event *ev) |
|
{ |
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struct trace_uprobe *tu = to_trace_uprobe(ev); |
|
|
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return trace_probe_is_enabled(&tu->tp); |
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} |
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|
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static bool trace_uprobe_match_command_head(struct trace_uprobe *tu, |
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int argc, const char **argv) |
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{ |
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char buf[MAX_ARGSTR_LEN + 1]; |
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int len; |
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|
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if (!argc) |
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return true; |
|
|
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len = strlen(tu->filename); |
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if (strncmp(tu->filename, argv[0], len) || argv[0][len] != ':') |
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return false; |
|
|
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if (tu->ref_ctr_offset == 0) |
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snprintf(buf, sizeof(buf), "0x%0*lx", |
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(int)(sizeof(void *) * 2), tu->offset); |
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else |
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snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)", |
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(int)(sizeof(void *) * 2), tu->offset, |
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tu->ref_ctr_offset); |
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if (strcmp(buf, &argv[0][len + 1])) |
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return false; |
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|
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argc--; argv++; |
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|
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return trace_probe_match_command_args(&tu->tp, argc, argv); |
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} |
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|
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static bool trace_uprobe_match(const char *system, const char *event, |
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int argc, const char **argv, struct dyn_event *ev) |
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{ |
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struct trace_uprobe *tu = to_trace_uprobe(ev); |
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|
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return strcmp(trace_probe_name(&tu->tp), event) == 0 && |
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(!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) && |
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trace_uprobe_match_command_head(tu, argc, argv); |
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} |
|
|
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static nokprobe_inline struct trace_uprobe * |
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trace_uprobe_primary_from_call(struct trace_event_call *call) |
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{ |
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struct trace_probe *tp; |
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|
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tp = trace_probe_primary_from_call(call); |
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if (WARN_ON_ONCE(!tp)) |
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return NULL; |
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|
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return container_of(tp, struct trace_uprobe, tp); |
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} |
|
|
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/* |
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* Allocate new trace_uprobe and initialize it (including uprobes). |
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*/ |
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static struct trace_uprobe * |
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alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) |
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{ |
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struct trace_uprobe *tu; |
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int ret; |
|
|
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tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL); |
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if (!tu) |
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return ERR_PTR(-ENOMEM); |
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|
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ret = trace_probe_init(&tu->tp, event, group, true); |
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if (ret < 0) |
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goto error; |
|
|
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dyn_event_init(&tu->devent, &trace_uprobe_ops); |
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tu->consumer.handler = uprobe_dispatcher; |
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if (is_ret) |
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tu->consumer.ret_handler = uretprobe_dispatcher; |
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init_trace_uprobe_filter(tu->tp.event->filter); |
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return tu; |
|
|
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error: |
|
kfree(tu); |
|
|
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return ERR_PTR(ret); |
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} |
|
|
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static void free_trace_uprobe(struct trace_uprobe *tu) |
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{ |
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if (!tu) |
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return; |
|
|
|
path_put(&tu->path); |
|
trace_probe_cleanup(&tu->tp); |
|
kfree(tu->filename); |
|
kfree(tu); |
|
} |
|
|
|
static struct trace_uprobe *find_probe_event(const char *event, const char *group) |
|
{ |
|
struct dyn_event *pos; |
|
struct trace_uprobe *tu; |
|
|
|
for_each_trace_uprobe(tu, pos) |
|
if (strcmp(trace_probe_name(&tu->tp), event) == 0 && |
|
strcmp(trace_probe_group_name(&tu->tp), group) == 0) |
|
return tu; |
|
|
|
return NULL; |
|
} |
|
|
|
/* Unregister a trace_uprobe and probe_event */ |
|
static int unregister_trace_uprobe(struct trace_uprobe *tu) |
|
{ |
|
int ret; |
|
|
|
if (trace_probe_has_sibling(&tu->tp)) |
|
goto unreg; |
|
|
|
ret = unregister_uprobe_event(tu); |
|
if (ret) |
|
return ret; |
|
|
|
unreg: |
|
dyn_event_remove(&tu->devent); |
|
trace_probe_unlink(&tu->tp); |
|
free_trace_uprobe(tu); |
|
return 0; |
|
} |
|
|
|
static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig, |
|
struct trace_uprobe *comp) |
|
{ |
|
struct trace_probe_event *tpe = orig->tp.event; |
|
struct trace_probe *pos; |
|
struct inode *comp_inode = d_real_inode(comp->path.dentry); |
|
int i; |
|
|
|
list_for_each_entry(pos, &tpe->probes, list) { |
|
orig = container_of(pos, struct trace_uprobe, tp); |
|
if (comp_inode != d_real_inode(orig->path.dentry) || |
|
comp->offset != orig->offset) |
|
continue; |
|
|
|
/* |
|
* trace_probe_compare_arg_type() ensured that nr_args and |
|
* each argument name and type are same. Let's compare comm. |
|
*/ |
|
for (i = 0; i < orig->tp.nr_args; i++) { |
|
if (strcmp(orig->tp.args[i].comm, |
|
comp->tp.args[i].comm)) |
|
break; |
|
} |
|
|
|
if (i == orig->tp.nr_args) |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to) |
|
{ |
|
int ret; |
|
|
|
ret = trace_probe_compare_arg_type(&tu->tp, &to->tp); |
|
if (ret) { |
|
/* Note that argument starts index = 2 */ |
|
trace_probe_log_set_index(ret + 1); |
|
trace_probe_log_err(0, DIFF_ARG_TYPE); |
|
return -EEXIST; |
|
} |
|
if (trace_uprobe_has_same_uprobe(to, tu)) { |
|
trace_probe_log_set_index(0); |
|
trace_probe_log_err(0, SAME_PROBE); |
|
return -EEXIST; |
|
} |
|
|
|
/* Append to existing event */ |
|
ret = trace_probe_append(&tu->tp, &to->tp); |
|
if (!ret) |
|
dyn_event_add(&tu->devent); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Uprobe with multiple reference counter is not allowed. i.e. |
|
* If inode and offset matches, reference counter offset *must* |
|
* match as well. Though, there is one exception: If user is |
|
* replacing old trace_uprobe with new one(same group/event), |
|
* then we allow same uprobe with new reference counter as far |
|
* as the new one does not conflict with any other existing |
|
* ones. |
|
*/ |
|
static int validate_ref_ctr_offset(struct trace_uprobe *new) |
|
{ |
|
struct dyn_event *pos; |
|
struct trace_uprobe *tmp; |
|
struct inode *new_inode = d_real_inode(new->path.dentry); |
|
|
|
for_each_trace_uprobe(tmp, pos) { |
|
if (new_inode == d_real_inode(tmp->path.dentry) && |
|
new->offset == tmp->offset && |
|
new->ref_ctr_offset != tmp->ref_ctr_offset) { |
|
pr_warn("Reference counter offset mismatch."); |
|
return -EINVAL; |
|
} |
|
} |
|
return 0; |
|
} |
|
|
|
/* Register a trace_uprobe and probe_event */ |
|
static int register_trace_uprobe(struct trace_uprobe *tu) |
|
{ |
|
struct trace_uprobe *old_tu; |
|
int ret; |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
ret = validate_ref_ctr_offset(tu); |
|
if (ret) |
|
goto end; |
|
|
|
/* register as an event */ |
|
old_tu = find_probe_event(trace_probe_name(&tu->tp), |
|
trace_probe_group_name(&tu->tp)); |
|
if (old_tu) { |
|
if (is_ret_probe(tu) != is_ret_probe(old_tu)) { |
|
trace_probe_log_set_index(0); |
|
trace_probe_log_err(0, DIFF_PROBE_TYPE); |
|
ret = -EEXIST; |
|
} else { |
|
ret = append_trace_uprobe(tu, old_tu); |
|
} |
|
goto end; |
|
} |
|
|
|
ret = register_uprobe_event(tu); |
|
if (ret) { |
|
pr_warn("Failed to register probe event(%d)\n", ret); |
|
goto end; |
|
} |
|
|
|
dyn_event_add(&tu->devent); |
|
|
|
end: |
|
mutex_unlock(&event_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Argument syntax: |
|
* - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET[%return][(REF)] [FETCHARGS] |
|
*/ |
|
static int __trace_uprobe_create(int argc, const char **argv) |
|
{ |
|
struct trace_uprobe *tu; |
|
const char *event = NULL, *group = UPROBE_EVENT_SYSTEM; |
|
char *arg, *filename, *rctr, *rctr_end, *tmp; |
|
char buf[MAX_EVENT_NAME_LEN]; |
|
struct path path; |
|
unsigned long offset, ref_ctr_offset; |
|
bool is_return = false; |
|
int i, ret; |
|
|
|
ret = 0; |
|
ref_ctr_offset = 0; |
|
|
|
switch (argv[0][0]) { |
|
case 'r': |
|
is_return = true; |
|
break; |
|
case 'p': |
|
break; |
|
default: |
|
return -ECANCELED; |
|
} |
|
|
|
if (argc < 2) |
|
return -ECANCELED; |
|
|
|
if (argv[0][1] == ':') |
|
event = &argv[0][2]; |
|
|
|
if (!strchr(argv[1], '/')) |
|
return -ECANCELED; |
|
|
|
filename = kstrdup(argv[1], GFP_KERNEL); |
|
if (!filename) |
|
return -ENOMEM; |
|
|
|
/* Find the last occurrence, in case the path contains ':' too. */ |
|
arg = strrchr(filename, ':'); |
|
if (!arg || !isdigit(arg[1])) { |
|
kfree(filename); |
|
return -ECANCELED; |
|
} |
|
|
|
trace_probe_log_init("trace_uprobe", argc, argv); |
|
trace_probe_log_set_index(1); /* filename is the 2nd argument */ |
|
|
|
*arg++ = '\0'; |
|
ret = kern_path(filename, LOOKUP_FOLLOW, &path); |
|
if (ret) { |
|
trace_probe_log_err(0, FILE_NOT_FOUND); |
|
kfree(filename); |
|
trace_probe_log_clear(); |
|
return ret; |
|
} |
|
if (!d_is_reg(path.dentry)) { |
|
trace_probe_log_err(0, NO_REGULAR_FILE); |
|
ret = -EINVAL; |
|
goto fail_address_parse; |
|
} |
|
|
|
/* Parse reference counter offset if specified. */ |
|
rctr = strchr(arg, '('); |
|
if (rctr) { |
|
rctr_end = strchr(rctr, ')'); |
|
if (!rctr_end) { |
|
ret = -EINVAL; |
|
rctr_end = rctr + strlen(rctr); |
|
trace_probe_log_err(rctr_end - filename, |
|
REFCNT_OPEN_BRACE); |
|
goto fail_address_parse; |
|
} else if (rctr_end[1] != '\0') { |
|
ret = -EINVAL; |
|
trace_probe_log_err(rctr_end + 1 - filename, |
|
BAD_REFCNT_SUFFIX); |
|
goto fail_address_parse; |
|
} |
|
|
|
*rctr++ = '\0'; |
|
*rctr_end = '\0'; |
|
ret = kstrtoul(rctr, 0, &ref_ctr_offset); |
|
if (ret) { |
|
trace_probe_log_err(rctr - filename, BAD_REFCNT); |
|
goto fail_address_parse; |
|
} |
|
} |
|
|
|
/* Check if there is %return suffix */ |
|
tmp = strchr(arg, '%'); |
|
if (tmp) { |
|
if (!strcmp(tmp, "%return")) { |
|
*tmp = '\0'; |
|
is_return = true; |
|
} else { |
|
trace_probe_log_err(tmp - filename, BAD_ADDR_SUFFIX); |
|
ret = -EINVAL; |
|
goto fail_address_parse; |
|
} |
|
} |
|
|
|
/* Parse uprobe offset. */ |
|
ret = kstrtoul(arg, 0, &offset); |
|
if (ret) { |
|
trace_probe_log_err(arg - filename, BAD_UPROBE_OFFS); |
|
goto fail_address_parse; |
|
} |
|
|
|
/* setup a probe */ |
|
trace_probe_log_set_index(0); |
|
if (event) { |
|
ret = traceprobe_parse_event_name(&event, &group, buf, |
|
event - argv[0]); |
|
if (ret) |
|
goto fail_address_parse; |
|
} else { |
|
char *tail; |
|
char *ptr; |
|
|
|
tail = kstrdup(kbasename(filename), GFP_KERNEL); |
|
if (!tail) { |
|
ret = -ENOMEM; |
|
goto fail_address_parse; |
|
} |
|
|
|
ptr = strpbrk(tail, ".-_"); |
|
if (ptr) |
|
*ptr = '\0'; |
|
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset); |
|
event = buf; |
|
kfree(tail); |
|
} |
|
|
|
argc -= 2; |
|
argv += 2; |
|
|
|
tu = alloc_trace_uprobe(group, event, argc, is_return); |
|
if (IS_ERR(tu)) { |
|
ret = PTR_ERR(tu); |
|
/* This must return -ENOMEM otherwise there is a bug */ |
|
WARN_ON_ONCE(ret != -ENOMEM); |
|
goto fail_address_parse; |
|
} |
|
tu->offset = offset; |
|
tu->ref_ctr_offset = ref_ctr_offset; |
|
tu->path = path; |
|
tu->filename = filename; |
|
|
|
/* parse arguments */ |
|
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { |
|
tmp = kstrdup(argv[i], GFP_KERNEL); |
|
if (!tmp) { |
|
ret = -ENOMEM; |
|
goto error; |
|
} |
|
|
|
trace_probe_log_set_index(i + 2); |
|
ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp, |
|
is_return ? TPARG_FL_RETURN : 0); |
|
kfree(tmp); |
|
if (ret) |
|
goto error; |
|
} |
|
|
|
ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)); |
|
if (ret < 0) |
|
goto error; |
|
|
|
ret = register_trace_uprobe(tu); |
|
if (!ret) |
|
goto out; |
|
|
|
error: |
|
free_trace_uprobe(tu); |
|
out: |
|
trace_probe_log_clear(); |
|
return ret; |
|
|
|
fail_address_parse: |
|
trace_probe_log_clear(); |
|
path_put(&path); |
|
kfree(filename); |
|
|
|
return ret; |
|
} |
|
|
|
int trace_uprobe_create(const char *raw_command) |
|
{ |
|
return trace_probe_create(raw_command, __trace_uprobe_create); |
|
} |
|
|
|
static int create_or_delete_trace_uprobe(const char *raw_command) |
|
{ |
|
int ret; |
|
|
|
if (raw_command[0] == '-') |
|
return dyn_event_release(raw_command, &trace_uprobe_ops); |
|
|
|
ret = trace_uprobe_create(raw_command); |
|
return ret == -ECANCELED ? -EINVAL : ret; |
|
} |
|
|
|
static int trace_uprobe_release(struct dyn_event *ev) |
|
{ |
|
struct trace_uprobe *tu = to_trace_uprobe(ev); |
|
|
|
return unregister_trace_uprobe(tu); |
|
} |
|
|
|
/* Probes listing interfaces */ |
|
static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev) |
|
{ |
|
struct trace_uprobe *tu = to_trace_uprobe(ev); |
|
char c = is_ret_probe(tu) ? 'r' : 'p'; |
|
int i; |
|
|
|
seq_printf(m, "%c:%s/%s %s:0x%0*lx", c, trace_probe_group_name(&tu->tp), |
|
trace_probe_name(&tu->tp), tu->filename, |
|
(int)(sizeof(void *) * 2), tu->offset); |
|
|
|
if (tu->ref_ctr_offset) |
|
seq_printf(m, "(0x%lx)", tu->ref_ctr_offset); |
|
|
|
for (i = 0; i < tu->tp.nr_args; i++) |
|
seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); |
|
|
|
seq_putc(m, '\n'); |
|
return 0; |
|
} |
|
|
|
static int probes_seq_show(struct seq_file *m, void *v) |
|
{ |
|
struct dyn_event *ev = v; |
|
|
|
if (!is_trace_uprobe(ev)) |
|
return 0; |
|
|
|
return trace_uprobe_show(m, ev); |
|
} |
|
|
|
static const struct seq_operations probes_seq_op = { |
|
.start = dyn_event_seq_start, |
|
.next = dyn_event_seq_next, |
|
.stop = dyn_event_seq_stop, |
|
.show = probes_seq_show |
|
}; |
|
|
|
static int probes_open(struct inode *inode, struct file *file) |
|
{ |
|
int ret; |
|
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS); |
|
if (ret) |
|
return ret; |
|
|
|
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
|
ret = dyn_events_release_all(&trace_uprobe_ops); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
return seq_open(file, &probes_seq_op); |
|
} |
|
|
|
static ssize_t probes_write(struct file *file, const char __user *buffer, |
|
size_t count, loff_t *ppos) |
|
{ |
|
return trace_parse_run_command(file, buffer, count, ppos, |
|
create_or_delete_trace_uprobe); |
|
} |
|
|
|
static const struct file_operations uprobe_events_ops = { |
|
.owner = THIS_MODULE, |
|
.open = probes_open, |
|
.read = seq_read, |
|
.llseek = seq_lseek, |
|
.release = seq_release, |
|
.write = probes_write, |
|
}; |
|
|
|
/* Probes profiling interfaces */ |
|
static int probes_profile_seq_show(struct seq_file *m, void *v) |
|
{ |
|
struct dyn_event *ev = v; |
|
struct trace_uprobe *tu; |
|
|
|
if (!is_trace_uprobe(ev)) |
|
return 0; |
|
|
|
tu = to_trace_uprobe(ev); |
|
seq_printf(m, " %s %-44s %15lu\n", tu->filename, |
|
trace_probe_name(&tu->tp), tu->nhit); |
|
return 0; |
|
} |
|
|
|
static const struct seq_operations profile_seq_op = { |
|
.start = dyn_event_seq_start, |
|
.next = dyn_event_seq_next, |
|
.stop = dyn_event_seq_stop, |
|
.show = probes_profile_seq_show |
|
}; |
|
|
|
static int profile_open(struct inode *inode, struct file *file) |
|
{ |
|
int ret; |
|
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS); |
|
if (ret) |
|
return ret; |
|
|
|
return seq_open(file, &profile_seq_op); |
|
} |
|
|
|
static const struct file_operations uprobe_profile_ops = { |
|
.owner = THIS_MODULE, |
|
.open = profile_open, |
|
.read = seq_read, |
|
.llseek = seq_lseek, |
|
.release = seq_release, |
|
}; |
|
|
|
struct uprobe_cpu_buffer { |
|
struct mutex mutex; |
|
void *buf; |
|
}; |
|
static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer; |
|
static int uprobe_buffer_refcnt; |
|
|
|
static int uprobe_buffer_init(void) |
|
{ |
|
int cpu, err_cpu; |
|
|
|
uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer); |
|
if (uprobe_cpu_buffer == NULL) |
|
return -ENOMEM; |
|
|
|
for_each_possible_cpu(cpu) { |
|
struct page *p = alloc_pages_node(cpu_to_node(cpu), |
|
GFP_KERNEL, 0); |
|
if (p == NULL) { |
|
err_cpu = cpu; |
|
goto err; |
|
} |
|
per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p); |
|
mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex); |
|
} |
|
|
|
return 0; |
|
|
|
err: |
|
for_each_possible_cpu(cpu) { |
|
if (cpu == err_cpu) |
|
break; |
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf); |
|
} |
|
|
|
free_percpu(uprobe_cpu_buffer); |
|
return -ENOMEM; |
|
} |
|
|
|
static int uprobe_buffer_enable(void) |
|
{ |
|
int ret = 0; |
|
|
|
BUG_ON(!mutex_is_locked(&event_mutex)); |
|
|
|
if (uprobe_buffer_refcnt++ == 0) { |
|
ret = uprobe_buffer_init(); |
|
if (ret < 0) |
|
uprobe_buffer_refcnt--; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static void uprobe_buffer_disable(void) |
|
{ |
|
int cpu; |
|
|
|
BUG_ON(!mutex_is_locked(&event_mutex)); |
|
|
|
if (--uprobe_buffer_refcnt == 0) { |
|
for_each_possible_cpu(cpu) |
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, |
|
cpu)->buf); |
|
|
|
free_percpu(uprobe_cpu_buffer); |
|
uprobe_cpu_buffer = NULL; |
|
} |
|
} |
|
|
|
static struct uprobe_cpu_buffer *uprobe_buffer_get(void) |
|
{ |
|
struct uprobe_cpu_buffer *ucb; |
|
int cpu; |
|
|
|
cpu = raw_smp_processor_id(); |
|
ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu); |
|
|
|
/* |
|
* Use per-cpu buffers for fastest access, but we might migrate |
|
* so the mutex makes sure we have sole access to it. |
|
*/ |
|
mutex_lock(&ucb->mutex); |
|
|
|
return ucb; |
|
} |
|
|
|
static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb) |
|
{ |
|
mutex_unlock(&ucb->mutex); |
|
} |
|
|
|
static void __uprobe_trace_func(struct trace_uprobe *tu, |
|
unsigned long func, struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize, |
|
struct trace_event_file *trace_file) |
|
{ |
|
struct uprobe_trace_entry_head *entry; |
|
struct trace_buffer *buffer; |
|
struct ring_buffer_event *event; |
|
void *data; |
|
int size, esize; |
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp); |
|
|
|
WARN_ON(call != trace_file->event_call); |
|
|
|
if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE)) |
|
return; |
|
|
|
if (trace_trigger_soft_disabled(trace_file)) |
|
return; |
|
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); |
|
size = esize + tu->tp.size + dsize; |
|
event = trace_event_buffer_lock_reserve(&buffer, trace_file, |
|
call->event.type, size, 0); |
|
if (!event) |
|
return; |
|
|
|
entry = ring_buffer_event_data(event); |
|
if (is_ret_probe(tu)) { |
|
entry->vaddr[0] = func; |
|
entry->vaddr[1] = instruction_pointer(regs); |
|
data = DATAOF_TRACE_ENTRY(entry, true); |
|
} else { |
|
entry->vaddr[0] = instruction_pointer(regs); |
|
data = DATAOF_TRACE_ENTRY(entry, false); |
|
} |
|
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize); |
|
|
|
event_trigger_unlock_commit(trace_file, buffer, event, entry, 0); |
|
} |
|
|
|
/* uprobe handler */ |
|
static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize) |
|
{ |
|
struct event_file_link *link; |
|
|
|
if (is_ret_probe(tu)) |
|
return 0; |
|
|
|
rcu_read_lock(); |
|
trace_probe_for_each_link_rcu(link, &tu->tp) |
|
__uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file); |
|
rcu_read_unlock(); |
|
|
|
return 0; |
|
} |
|
|
|
static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func, |
|
struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize) |
|
{ |
|
struct event_file_link *link; |
|
|
|
rcu_read_lock(); |
|
trace_probe_for_each_link_rcu(link, &tu->tp) |
|
__uprobe_trace_func(tu, func, regs, ucb, dsize, link->file); |
|
rcu_read_unlock(); |
|
} |
|
|
|
/* Event entry printers */ |
|
static enum print_line_t |
|
print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event) |
|
{ |
|
struct uprobe_trace_entry_head *entry; |
|
struct trace_seq *s = &iter->seq; |
|
struct trace_uprobe *tu; |
|
u8 *data; |
|
|
|
entry = (struct uprobe_trace_entry_head *)iter->ent; |
|
tu = trace_uprobe_primary_from_call( |
|
container_of(event, struct trace_event_call, event)); |
|
if (unlikely(!tu)) |
|
goto out; |
|
|
|
if (is_ret_probe(tu)) { |
|
trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", |
|
trace_probe_name(&tu->tp), |
|
entry->vaddr[1], entry->vaddr[0]); |
|
data = DATAOF_TRACE_ENTRY(entry, true); |
|
} else { |
|
trace_seq_printf(s, "%s: (0x%lx)", |
|
trace_probe_name(&tu->tp), |
|
entry->vaddr[0]); |
|
data = DATAOF_TRACE_ENTRY(entry, false); |
|
} |
|
|
|
if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0) |
|
goto out; |
|
|
|
trace_seq_putc(s, '\n'); |
|
|
|
out: |
|
return trace_handle_return(s); |
|
} |
|
|
|
typedef bool (*filter_func_t)(struct uprobe_consumer *self, |
|
enum uprobe_filter_ctx ctx, |
|
struct mm_struct *mm); |
|
|
|
static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter) |
|
{ |
|
int ret; |
|
|
|
tu->consumer.filter = filter; |
|
tu->inode = d_real_inode(tu->path.dentry); |
|
|
|
if (tu->ref_ctr_offset) |
|
ret = uprobe_register_refctr(tu->inode, tu->offset, |
|
tu->ref_ctr_offset, &tu->consumer); |
|
else |
|
ret = uprobe_register(tu->inode, tu->offset, &tu->consumer); |
|
|
|
if (ret) |
|
tu->inode = NULL; |
|
|
|
return ret; |
|
} |
|
|
|
static void __probe_event_disable(struct trace_probe *tp) |
|
{ |
|
struct trace_probe *pos; |
|
struct trace_uprobe *tu; |
|
|
|
tu = container_of(tp, struct trace_uprobe, tp); |
|
WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter)); |
|
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
|
tu = container_of(pos, struct trace_uprobe, tp); |
|
if (!tu->inode) |
|
continue; |
|
|
|
uprobe_unregister(tu->inode, tu->offset, &tu->consumer); |
|
tu->inode = NULL; |
|
} |
|
} |
|
|
|
static int probe_event_enable(struct trace_event_call *call, |
|
struct trace_event_file *file, filter_func_t filter) |
|
{ |
|
struct trace_probe *pos, *tp; |
|
struct trace_uprobe *tu; |
|
bool enabled; |
|
int ret; |
|
|
|
tp = trace_probe_primary_from_call(call); |
|
if (WARN_ON_ONCE(!tp)) |
|
return -ENODEV; |
|
enabled = trace_probe_is_enabled(tp); |
|
|
|
/* This may also change "enabled" state */ |
|
if (file) { |
|
if (trace_probe_test_flag(tp, TP_FLAG_PROFILE)) |
|
return -EINTR; |
|
|
|
ret = trace_probe_add_file(tp, file); |
|
if (ret < 0) |
|
return ret; |
|
} else { |
|
if (trace_probe_test_flag(tp, TP_FLAG_TRACE)) |
|
return -EINTR; |
|
|
|
trace_probe_set_flag(tp, TP_FLAG_PROFILE); |
|
} |
|
|
|
tu = container_of(tp, struct trace_uprobe, tp); |
|
WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter)); |
|
|
|
if (enabled) |
|
return 0; |
|
|
|
ret = uprobe_buffer_enable(); |
|
if (ret) |
|
goto err_flags; |
|
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
|
tu = container_of(pos, struct trace_uprobe, tp); |
|
ret = trace_uprobe_enable(tu, filter); |
|
if (ret) { |
|
__probe_event_disable(tp); |
|
goto err_buffer; |
|
} |
|
} |
|
|
|
return 0; |
|
|
|
err_buffer: |
|
uprobe_buffer_disable(); |
|
|
|
err_flags: |
|
if (file) |
|
trace_probe_remove_file(tp, file); |
|
else |
|
trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
|
|
|
return ret; |
|
} |
|
|
|
static void probe_event_disable(struct trace_event_call *call, |
|
struct trace_event_file *file) |
|
{ |
|
struct trace_probe *tp; |
|
|
|
tp = trace_probe_primary_from_call(call); |
|
if (WARN_ON_ONCE(!tp)) |
|
return; |
|
|
|
if (!trace_probe_is_enabled(tp)) |
|
return; |
|
|
|
if (file) { |
|
if (trace_probe_remove_file(tp, file) < 0) |
|
return; |
|
|
|
if (trace_probe_is_enabled(tp)) |
|
return; |
|
} else |
|
trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
|
|
|
__probe_event_disable(tp); |
|
uprobe_buffer_disable(); |
|
} |
|
|
|
static int uprobe_event_define_fields(struct trace_event_call *event_call) |
|
{ |
|
int ret, size; |
|
struct uprobe_trace_entry_head field; |
|
struct trace_uprobe *tu; |
|
|
|
tu = trace_uprobe_primary_from_call(event_call); |
|
if (unlikely(!tu)) |
|
return -ENODEV; |
|
|
|
if (is_ret_probe(tu)) { |
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0); |
|
DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0); |
|
size = SIZEOF_TRACE_ENTRY(true); |
|
} else { |
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0); |
|
size = SIZEOF_TRACE_ENTRY(false); |
|
} |
|
|
|
return traceprobe_define_arg_fields(event_call, size, &tu->tp); |
|
} |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
static bool |
|
__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm) |
|
{ |
|
struct perf_event *event; |
|
|
|
if (filter->nr_systemwide) |
|
return true; |
|
|
|
list_for_each_entry(event, &filter->perf_events, hw.tp_list) { |
|
if (event->hw.target->mm == mm) |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static inline bool |
|
trace_uprobe_filter_event(struct trace_uprobe_filter *filter, |
|
struct perf_event *event) |
|
{ |
|
return __uprobe_perf_filter(filter, event->hw.target->mm); |
|
} |
|
|
|
static bool trace_uprobe_filter_remove(struct trace_uprobe_filter *filter, |
|
struct perf_event *event) |
|
{ |
|
bool done; |
|
|
|
write_lock(&filter->rwlock); |
|
if (event->hw.target) { |
|
list_del(&event->hw.tp_list); |
|
done = filter->nr_systemwide || |
|
(event->hw.target->flags & PF_EXITING) || |
|
trace_uprobe_filter_event(filter, event); |
|
} else { |
|
filter->nr_systemwide--; |
|
done = filter->nr_systemwide; |
|
} |
|
write_unlock(&filter->rwlock); |
|
|
|
return done; |
|
} |
|
|
|
/* This returns true if the filter always covers target mm */ |
|
static bool trace_uprobe_filter_add(struct trace_uprobe_filter *filter, |
|
struct perf_event *event) |
|
{ |
|
bool done; |
|
|
|
write_lock(&filter->rwlock); |
|
if (event->hw.target) { |
|
/* |
|
* event->parent != NULL means copy_process(), we can avoid |
|
* uprobe_apply(). current->mm must be probed and we can rely |
|
* on dup_mmap() which preserves the already installed bp's. |
|
* |
|
* attr.enable_on_exec means that exec/mmap will install the |
|
* breakpoints we need. |
|
*/ |
|
done = filter->nr_systemwide || |
|
event->parent || event->attr.enable_on_exec || |
|
trace_uprobe_filter_event(filter, event); |
|
list_add(&event->hw.tp_list, &filter->perf_events); |
|
} else { |
|
done = filter->nr_systemwide; |
|
filter->nr_systemwide++; |
|
} |
|
write_unlock(&filter->rwlock); |
|
|
|
return done; |
|
} |
|
|
|
static int uprobe_perf_close(struct trace_event_call *call, |
|
struct perf_event *event) |
|
{ |
|
struct trace_probe *pos, *tp; |
|
struct trace_uprobe *tu; |
|
int ret = 0; |
|
|
|
tp = trace_probe_primary_from_call(call); |
|
if (WARN_ON_ONCE(!tp)) |
|
return -ENODEV; |
|
|
|
tu = container_of(tp, struct trace_uprobe, tp); |
|
if (trace_uprobe_filter_remove(tu->tp.event->filter, event)) |
|
return 0; |
|
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
|
tu = container_of(pos, struct trace_uprobe, tp); |
|
ret = uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); |
|
if (ret) |
|
break; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int uprobe_perf_open(struct trace_event_call *call, |
|
struct perf_event *event) |
|
{ |
|
struct trace_probe *pos, *tp; |
|
struct trace_uprobe *tu; |
|
int err = 0; |
|
|
|
tp = trace_probe_primary_from_call(call); |
|
if (WARN_ON_ONCE(!tp)) |
|
return -ENODEV; |
|
|
|
tu = container_of(tp, struct trace_uprobe, tp); |
|
if (trace_uprobe_filter_add(tu->tp.event->filter, event)) |
|
return 0; |
|
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
|
err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); |
|
if (err) { |
|
uprobe_perf_close(call, event); |
|
break; |
|
} |
|
} |
|
|
|
return err; |
|
} |
|
|
|
static bool uprobe_perf_filter(struct uprobe_consumer *uc, |
|
enum uprobe_filter_ctx ctx, struct mm_struct *mm) |
|
{ |
|
struct trace_uprobe_filter *filter; |
|
struct trace_uprobe *tu; |
|
int ret; |
|
|
|
tu = container_of(uc, struct trace_uprobe, consumer); |
|
filter = tu->tp.event->filter; |
|
|
|
read_lock(&filter->rwlock); |
|
ret = __uprobe_perf_filter(filter, mm); |
|
read_unlock(&filter->rwlock); |
|
|
|
return ret; |
|
} |
|
|
|
static void __uprobe_perf_func(struct trace_uprobe *tu, |
|
unsigned long func, struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize) |
|
{ |
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp); |
|
struct uprobe_trace_entry_head *entry; |
|
struct hlist_head *head; |
|
void *data; |
|
int size, esize; |
|
int rctx; |
|
|
|
if (bpf_prog_array_valid(call)) { |
|
u32 ret; |
|
|
|
preempt_disable(); |
|
ret = trace_call_bpf(call, regs); |
|
preempt_enable(); |
|
if (!ret) |
|
return; |
|
} |
|
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); |
|
|
|
size = esize + tu->tp.size + dsize; |
|
size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32); |
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough")) |
|
return; |
|
|
|
preempt_disable(); |
|
head = this_cpu_ptr(call->perf_events); |
|
if (hlist_empty(head)) |
|
goto out; |
|
|
|
entry = perf_trace_buf_alloc(size, NULL, &rctx); |
|
if (!entry) |
|
goto out; |
|
|
|
if (is_ret_probe(tu)) { |
|
entry->vaddr[0] = func; |
|
entry->vaddr[1] = instruction_pointer(regs); |
|
data = DATAOF_TRACE_ENTRY(entry, true); |
|
} else { |
|
entry->vaddr[0] = instruction_pointer(regs); |
|
data = DATAOF_TRACE_ENTRY(entry, false); |
|
} |
|
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize); |
|
|
|
if (size - esize > tu->tp.size + dsize) { |
|
int len = tu->tp.size + dsize; |
|
|
|
memset(data + len, 0, size - esize - len); |
|
} |
|
|
|
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
|
head, NULL); |
|
out: |
|
preempt_enable(); |
|
} |
|
|
|
/* uprobe profile handler */ |
|
static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize) |
|
{ |
|
if (!uprobe_perf_filter(&tu->consumer, 0, current->mm)) |
|
return UPROBE_HANDLER_REMOVE; |
|
|
|
if (!is_ret_probe(tu)) |
|
__uprobe_perf_func(tu, 0, regs, ucb, dsize); |
|
return 0; |
|
} |
|
|
|
static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func, |
|
struct pt_regs *regs, |
|
struct uprobe_cpu_buffer *ucb, int dsize) |
|
{ |
|
__uprobe_perf_func(tu, func, regs, ucb, dsize); |
|
} |
|
|
|
int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type, |
|
const char **filename, u64 *probe_offset, |
|
bool perf_type_tracepoint) |
|
{ |
|
const char *pevent = trace_event_name(event->tp_event); |
|
const char *group = event->tp_event->class->system; |
|
struct trace_uprobe *tu; |
|
|
|
if (perf_type_tracepoint) |
|
tu = find_probe_event(pevent, group); |
|
else |
|
tu = trace_uprobe_primary_from_call(event->tp_event); |
|
if (!tu) |
|
return -EINVAL; |
|
|
|
*fd_type = is_ret_probe(tu) ? BPF_FD_TYPE_URETPROBE |
|
: BPF_FD_TYPE_UPROBE; |
|
*filename = tu->filename; |
|
*probe_offset = tu->offset; |
|
return 0; |
|
} |
|
#endif /* CONFIG_PERF_EVENTS */ |
|
|
|
static int |
|
trace_uprobe_register(struct trace_event_call *event, enum trace_reg type, |
|
void *data) |
|
{ |
|
struct trace_event_file *file = data; |
|
|
|
switch (type) { |
|
case TRACE_REG_REGISTER: |
|
return probe_event_enable(event, file, NULL); |
|
|
|
case TRACE_REG_UNREGISTER: |
|
probe_event_disable(event, file); |
|
return 0; |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
case TRACE_REG_PERF_REGISTER: |
|
return probe_event_enable(event, NULL, uprobe_perf_filter); |
|
|
|
case TRACE_REG_PERF_UNREGISTER: |
|
probe_event_disable(event, NULL); |
|
return 0; |
|
|
|
case TRACE_REG_PERF_OPEN: |
|
return uprobe_perf_open(event, data); |
|
|
|
case TRACE_REG_PERF_CLOSE: |
|
return uprobe_perf_close(event, data); |
|
|
|
#endif |
|
default: |
|
return 0; |
|
} |
|
} |
|
|
|
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) |
|
{ |
|
struct trace_uprobe *tu; |
|
struct uprobe_dispatch_data udd; |
|
struct uprobe_cpu_buffer *ucb; |
|
int dsize, esize; |
|
int ret = 0; |
|
|
|
|
|
tu = container_of(con, struct trace_uprobe, consumer); |
|
tu->nhit++; |
|
|
|
udd.tu = tu; |
|
udd.bp_addr = instruction_pointer(regs); |
|
|
|
current->utask->vaddr = (unsigned long) &udd; |
|
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer)) |
|
return 0; |
|
|
|
dsize = __get_data_size(&tu->tp, regs); |
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); |
|
|
|
ucb = uprobe_buffer_get(); |
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize); |
|
|
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE)) |
|
ret |= uprobe_trace_func(tu, regs, ucb, dsize); |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE)) |
|
ret |= uprobe_perf_func(tu, regs, ucb, dsize); |
|
#endif |
|
uprobe_buffer_put(ucb); |
|
return ret; |
|
} |
|
|
|
static int uretprobe_dispatcher(struct uprobe_consumer *con, |
|
unsigned long func, struct pt_regs *regs) |
|
{ |
|
struct trace_uprobe *tu; |
|
struct uprobe_dispatch_data udd; |
|
struct uprobe_cpu_buffer *ucb; |
|
int dsize, esize; |
|
|
|
tu = container_of(con, struct trace_uprobe, consumer); |
|
|
|
udd.tu = tu; |
|
udd.bp_addr = func; |
|
|
|
current->utask->vaddr = (unsigned long) &udd; |
|
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer)) |
|
return 0; |
|
|
|
dsize = __get_data_size(&tu->tp, regs); |
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); |
|
|
|
ucb = uprobe_buffer_get(); |
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize); |
|
|
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE)) |
|
uretprobe_trace_func(tu, func, regs, ucb, dsize); |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE)) |
|
uretprobe_perf_func(tu, func, regs, ucb, dsize); |
|
#endif |
|
uprobe_buffer_put(ucb); |
|
return 0; |
|
} |
|
|
|
static struct trace_event_functions uprobe_funcs = { |
|
.trace = print_uprobe_event |
|
}; |
|
|
|
static struct trace_event_fields uprobe_fields_array[] = { |
|
{ .type = TRACE_FUNCTION_TYPE, |
|
.define_fields = uprobe_event_define_fields }, |
|
{} |
|
}; |
|
|
|
static inline void init_trace_event_call(struct trace_uprobe *tu) |
|
{ |
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp); |
|
call->event.funcs = &uprobe_funcs; |
|
call->class->fields_array = uprobe_fields_array; |
|
|
|
call->flags = TRACE_EVENT_FL_UPROBE | TRACE_EVENT_FL_CAP_ANY; |
|
call->class->reg = trace_uprobe_register; |
|
} |
|
|
|
static int register_uprobe_event(struct trace_uprobe *tu) |
|
{ |
|
init_trace_event_call(tu); |
|
|
|
return trace_probe_register_event_call(&tu->tp); |
|
} |
|
|
|
static int unregister_uprobe_event(struct trace_uprobe *tu) |
|
{ |
|
return trace_probe_unregister_event_call(&tu->tp); |
|
} |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
struct trace_event_call * |
|
create_local_trace_uprobe(char *name, unsigned long offs, |
|
unsigned long ref_ctr_offset, bool is_return) |
|
{ |
|
struct trace_uprobe *tu; |
|
struct path path; |
|
int ret; |
|
|
|
ret = kern_path(name, LOOKUP_FOLLOW, &path); |
|
if (ret) |
|
return ERR_PTR(ret); |
|
|
|
if (!d_is_reg(path.dentry)) { |
|
path_put(&path); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
/* |
|
* local trace_kprobes are not added to dyn_event, so they are never |
|
* searched in find_trace_kprobe(). Therefore, there is no concern of |
|
* duplicated name "DUMMY_EVENT" here. |
|
*/ |
|
tu = alloc_trace_uprobe(UPROBE_EVENT_SYSTEM, "DUMMY_EVENT", 0, |
|
is_return); |
|
|
|
if (IS_ERR(tu)) { |
|
pr_info("Failed to allocate trace_uprobe.(%d)\n", |
|
(int)PTR_ERR(tu)); |
|
path_put(&path); |
|
return ERR_CAST(tu); |
|
} |
|
|
|
tu->offset = offs; |
|
tu->path = path; |
|
tu->ref_ctr_offset = ref_ctr_offset; |
|
tu->filename = kstrdup(name, GFP_KERNEL); |
|
init_trace_event_call(tu); |
|
|
|
if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) { |
|
ret = -ENOMEM; |
|
goto error; |
|
} |
|
|
|
return trace_probe_event_call(&tu->tp); |
|
error: |
|
free_trace_uprobe(tu); |
|
return ERR_PTR(ret); |
|
} |
|
|
|
void destroy_local_trace_uprobe(struct trace_event_call *event_call) |
|
{ |
|
struct trace_uprobe *tu; |
|
|
|
tu = trace_uprobe_primary_from_call(event_call); |
|
|
|
free_trace_uprobe(tu); |
|
} |
|
#endif /* CONFIG_PERF_EVENTS */ |
|
|
|
/* Make a trace interface for controlling probe points */ |
|
static __init int init_uprobe_trace(void) |
|
{ |
|
int ret; |
|
|
|
ret = dyn_event_register(&trace_uprobe_ops); |
|
if (ret) |
|
return ret; |
|
|
|
ret = tracing_init_dentry(); |
|
if (ret) |
|
return 0; |
|
|
|
trace_create_file("uprobe_events", 0644, NULL, |
|
NULL, &uprobe_events_ops); |
|
/* Profile interface */ |
|
trace_create_file("uprobe_profile", 0444, NULL, |
|
NULL, &uprobe_profile_ops); |
|
return 0; |
|
} |
|
|
|
fs_initcall(init_uprobe_trace);
|
|
|