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| author | Namhyung Kim <namhyung.kim@lge.com> | 2013-11-25 05:42:47 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-01-03 02:57:05 +0100 |
| commit | b7e0bf341f6cfa92ae0a0e3d0c3496729595e1e9 (patch) | |
| tree | 0831ae7ab363f3789c5cb14bbf4973bfe17287bc /kernel/trace/trace_uprobe.c | |
| parent | uprobes: Allocate ->utask before handler_chain() for tracing handlers (diff) | |
| download | linux-b7e0bf341f6cfa92ae0a0e3d0c3496729595e1e9.tar.xz linux-b7e0bf341f6cfa92ae0a0e3d0c3496729595e1e9.zip | |
tracing/uprobes: Add @+file_offset fetch method
Enable to fetch data from a file offset. Currently it only supports
fetching from same binary uprobe set. It'll translate the file offset
to a proper virtual address in the process.
The syntax is "@+OFFSET" as it does similar to normal memory fetching
(@ADDR) which does no address translation.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'kernel/trace/trace_uprobe.c')
| -rw-r--r-- | kernel/trace/trace_uprobe.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 794e8bc171f3..1fdea6d3f851 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); |