5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
[ Upstream commit e38e2c6a9efc435f9de344b7c91f7697e01b47d5 ]
Fix to update dynamic data counter ('dyndata') and max length ('maxlen')
only if the fetcharg uses the dynamic data. Also get out arg->dynamic
from unlikely(). This makes dynamic data address wrong if
process_fetch_insn() returns error on !arg->dynamic case.
Link: https://lore.kernel.org/all/168908494781.123124.8160245359962103684.stgit@devnote2/
Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Link: https://lore.kernel.org/all/20230710233400.5aaf024e@xxxxxxxxxxxxxxxxxx/
Fixes: 9178412ddf5a ("tracing: probeevent: Return consumed bytes of dynamic area")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
kernel/trace/trace_probe_tmpl.h | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index bbb479b3ba8fd..cf14a37dff8c8 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -206,11 +206,13 @@ store_trace_args(void *data, struct trace_probe *tp, void *rec,
if (unlikely(arg->dynamic))
*dl = make_data_loc(maxlen, dyndata - base);
ret = process_fetch_insn(arg->code, rec, dl, base);
- if (unlikely(ret < 0 && arg->dynamic)) {
- *dl = make_data_loc(0, dyndata - base);
- } else {
- dyndata += ret;
- maxlen -= ret;
+ if (arg->dynamic) {
+ if (unlikely(ret < 0)) {
+ *dl = make_data_loc(0, dyndata - base);
+ } else {
+ dyndata += ret;
+ maxlen -= ret;
+ }
}
}
}
--
2.40.1
