4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
commit 9e52b32567126fe146f198971364f68d3bc5233f upstream.
Always try to parse an address, since kstrtoul() will safely fail when
given a symbol as input. If that fails (which will be the case for a
symbol), try to parse a symbol instead.
This allows creating a probe such as:
p:probe/vlan_gro_receive 8021q:vlan_gro_receive+0
Which is necessary for this command to work:
perf probe -m 8021q -a vlan_gro_receive
Link: http://lkml.kernel.org/r/fd72d666f45b114e2c5b9cf7e27b91de1ec966f1.1498122881.git.sd@xxxxxxxxxxxxxxx
Fixes: 413d37d1e ("tracing: Add kprobe-based event tracer")
Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace_kprobe.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -659,30 +659,25 @@ static int create_trace_kprobe(int argc,
pr_info("Probe point is not specified.\n");
return -EINVAL;
}
- if (isdigit(argv[1][0])) {
- if (is_return) {
- pr_info("Return probe point must be a symbol.\n");
- return -EINVAL;
- }
- /* an address specified */
- ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
- if (ret) {
- pr_info("Failed to parse address.\n");
- return ret;
- }
- } else {
+
+ /* try to parse an address. if that fails, try to read the
+ * input as a symbol. */
+ if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
/* a symbol specified */
symbol = argv[1];
/* TODO: support .init module functions */
ret = traceprobe_split_symbol_offset(symbol, &offset);
if (ret) {
- pr_info("Failed to parse symbol.\n");
+ pr_info("Failed to parse either an address or a symbol.\n");
return ret;
}
if (offset && is_return) {
pr_info("Return probe must be used without offset.\n");
return -EINVAL;
}
+ } else if (is_return) {
+ pr_info("Return probe point must be a symbol.\n");
+ return -EINVAL;
}
argc -= 2; argv += 2;