diff --git a/Documentation/trace/uprobetracer.txt b/Documentation/trace/uprobetracer.txt index 6e5cff263e2b81b47d29aaa3af7b3d687f174100..f1cf9a34ad9d714cc87f4dcf36b2b996e551403e 100644 --- a/Documentation/trace/uprobetracer.txt +++ b/Documentation/trace/uprobetracer.txt @@ -32,6 +32,7 @@ Synopsis of uprobe_tracer FETCHARGS : Arguments. Each probe can have up to 128 args. %REG : Fetch register REG @ADDR : Fetch memory at ADDR (ADDR should be in userspace) + @+OFFSET : Fetch memory at OFFSET (OFFSET from same file as PATH) $stackN : Fetch Nth entry of stack (N >= 0) $stack : Fetch stack address. $retval : Fetch return value.(*) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index f94a56915e698348de8621dd0d897fa6532fad1c..ce0ed8afb77e269d993a3fed313d859cd092b2e9 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -239,6 +239,14 @@ DEFINE_BASIC_FETCH_FUNCS(symbol) DEFINE_FETCH_symbol(string) DEFINE_FETCH_symbol(string_size) +/* kprobes don't support file_offset fetch methods */ +#define fetch_file_offset_u8 NULL +#define fetch_file_offset_u16 NULL +#define fetch_file_offset_u32 NULL +#define fetch_file_offset_u64 NULL +#define fetch_file_offset_string NULL +#define fetch_file_offset_string_size NULL + /* Fetch type information table */ const struct fetch_type kprobes_fetch_type_table[] = { /* Special types */ diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index a130d612e705c74118281df9c4ad4ff879b5ec15..8364a421b4dfc7bb8935cf4e9c128aa99de0776f 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -374,7 +374,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, } break; - case '@': /* memory or symbol */ + case '@': /* memory, file-offset or symbol */ if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) @@ -382,6 +382,17 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, f->fn = t->fetch[FETCH_MTD_memory]; f->data = (void *)param; + } else if (arg[1] == '+') { + /* kprobes don't support file offsets */ + if (is_kprobe) + return -EINVAL; + + ret = kstrtol(arg + 2, 0, &offset); + if (ret) + break; + + f->fn = t->fetch[FETCH_MTD_file_offset]; + f->data = (void *)offset; } else { /* uprobes don't support symbols */ if (!is_kprobe) diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 2d5b8f5f5310ada62b0bc4ace1556b91629f87bb..e29d743fef5de44039440d397f236c5cbcfd26bb 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -106,6 +106,7 @@ enum { FETCH_MTD_symbol, FETCH_MTD_deref, FETCH_MTD_bitfield, + FETCH_MTD_file_offset, FETCH_MTD_END, }; @@ -217,6 +218,7 @@ ASSIGN_FETCH_FUNC(memory, ftype), \ ASSIGN_FETCH_FUNC(symbol, ftype), \ ASSIGN_FETCH_FUNC(deref, ftype), \ ASSIGN_FETCH_FUNC(bitfield, ftype), \ +ASSIGN_FETCH_FUNC(file_offset, ftype), \ } \ } diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 794e8bc171f38d17f51e663da78729831fca6bbf..1fdea6d3f851b15162c80add785a9622fc83121b 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -70,6 +70,11 @@ static int unregister_uprobe_event(struct trace_uprobe *tu); static DEFINE_MUTEX(uprobe_lock); static LIST_HEAD(uprobe_list); +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; + static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs); @@ -175,6 +180,29 @@ static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, #define fetch_symbol_string NULL #define fetch_symbol_string_size NULL +static unsigned long translate_user_vaddr(void *file_offset) +{ + unsigned long base_addr; + struct uprobe_dispatch_data *udd; + + udd = (void *) current->utask->vaddr; + + base_addr = udd->bp_addr - udd->tu->offset; + return base_addr + (unsigned long)file_offset; +} + +#define DEFINE_FETCH_file_offset(type) \ +static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + void *vaddr = (void *)translate_user_vaddr(offset); \ + \ + FETCH_FUNC_NAME(memory, type)(regs, vaddr, dest); \ +} +DEFINE_BASIC_FETCH_FUNCS(file_offset) +DEFINE_FETCH_file_offset(string) +DEFINE_FETCH_file_offset(string_size) + /* Fetch type information table */ const struct fetch_type uprobes_fetch_type_table[] = { /* Special types */ @@ -1106,11 +1134,17 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; 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 (tu->tp.flags & TP_FLAG_TRACE) ret |= uprobe_trace_func(tu, regs); @@ -1125,9 +1159,15 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; tu = container_of(con, struct trace_uprobe, consumer); + udd.tu = tu; + udd.bp_addr = func; + + current->utask->vaddr = (unsigned long) &udd; + if (tu->tp.flags & TP_FLAG_TRACE) uretprobe_trace_func(tu, func, regs);