diff options
| author | Masami Hiramatsu <mhiramat@kernel.org> | 2019-05-15 14:38:30 +0900 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-05-25 23:04:42 -0400 |
| commit | 88903c464321cdbc2d473c24cbf311f576cf05bc (patch) | |
| tree | 79d0b37b1ac3b805d67651687f9ca866e5df059a /kernel/trace/trace_probe_tmpl.h | |
| parent | 3d7081822f7f9eab867d9bcc8fd635208ec438e0 (diff) | |
tracing/probe: Add ustring type for user-space string
Add "ustring" type for fetching user-space string from kprobe event.
User can specify ustring type at uprobe event, and it is same as
"string" for uprobe.
Note that probe-event provides this option but it doesn't choose the
correct type automatically since we have not way to decide the address
is in user-space or not on some arch (and on some other arch, you can
fetch the string by "string" type). So user must carefully check the
target code (e.g. if you see __user on the target variable) and
use this new type.
Link: http://lkml.kernel.org/r/155789871009.26965.14167558859557329331.stgit@devnote2
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_probe_tmpl.h')
| -rw-r--r-- | kernel/trace/trace_probe_tmpl.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index c30c61f12ddd..2e9e4dae8839 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -59,6 +59,9 @@ process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, static nokprobe_inline int fetch_store_strlen(unsigned long addr); static nokprobe_inline int fetch_store_string(unsigned long addr, void *dest, void *base); +static nokprobe_inline int fetch_store_strlen_user(unsigned long addr); +static nokprobe_inline int +fetch_store_string_user(unsigned long addr, void *dest, void *base); static nokprobe_inline int probe_mem_read(void *dest, void *src, size_t size); @@ -91,6 +94,10 @@ stage3: ret = fetch_store_strlen(val + code->offset); code++; goto array; + } else if (code->op == FETCH_OP_ST_USTRING) { + ret += fetch_store_strlen_user(val + code->offset); + code++; + goto array; } else return -EILSEQ; } @@ -106,6 +113,10 @@ stage3: loc = *(u32 *)dest; ret = fetch_store_string(val + code->offset, dest, base); break; + case FETCH_OP_ST_USTRING: + loc = *(u32 *)dest; + ret = fetch_store_string_user(val + code->offset, dest, base); + break; default: return -EILSEQ; } @@ -123,7 +134,8 @@ array: total += ret; if (++i < code->param) { code = s3; - if (s3->op != FETCH_OP_ST_STRING) { + if (s3->op != FETCH_OP_ST_STRING && + s3->op != FETCH_OP_ST_USTRING) { dest += s3->size; val += s3->size; goto stage3; |