On Wed, 6 Aug 2025 07:01:09 +0000
Pu Lehui <[email protected]> wrote:
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 4283ed4e8f59..138212f4ecde 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -1814,9 +1814,11 @@ int trace_get_user(struct trace_parser *parser, const
> char __user *ubuf,
> if (!*ppos)
> trace_parser_clear(parser);
>
> + parser->fail = false;
This should be set when the parser is initialized.
> +
> ret = get_user(ch, ubuf++);
> if (ret)
> - return ret;
> + goto fail;
>
> read++;
> cnt--;
> @@ -1830,7 +1832,7 @@ int trace_get_user(struct trace_parser *parser, const
> char __user *ubuf,
> while (cnt && isspace(ch)) {
> ret = get_user(ch, ubuf++);
> if (ret)
> - return ret;
> + goto fail;
> read++;
> cnt--;
> }
> @@ -1848,12 +1850,14 @@ int trace_get_user(struct trace_parser *parser, const
> char __user *ubuf,
> while (cnt && !isspace(ch) && ch) {
> if (parser->idx < parser->size - 1)
> parser->buffer[parser->idx++] = ch;
> - else
> - return -EINVAL;
> + else {
> + ret = -EINVAL;
> + goto fail;
> + }
>
> ret = get_user(ch, ubuf++);
> if (ret)
> - return ret;
> + goto fail;
> read++;
> cnt--;
> }
> @@ -1868,11 +1872,15 @@ int trace_get_user(struct trace_parser *parser, const
> char __user *ubuf,
> /* Make sure the parsed string always terminates with '\0'. */
> parser->buffer[parser->idx] = 0;
> } else {
> - return -EINVAL;
> + ret = -EINVAL;
> + goto fail;
> }
>
> *ppos += read;
> return read;
> +fail:
> + parser->fail = true;
Should have a helper function called: trace_parser_fail(parser) and use
that.
-- Steve
> + return ret;
> }
>
> /* TODO add a seq_buf_to_buffer() */
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index 1dbf1d3cf2f1..5072bb25a860 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -1292,6 +1292,7 @@ bool ftrace_event_is_function(struct trace_event_call
> *call);
> */
> struct trace_parser {
> bool cont;
> + bool fail;
> char *buffer;
> unsigned idx;
> unsigned size;
> @@ -1299,7 +1300,7 @@ struct trace_parser {
>
> static inline bool trace_parser_loaded(struct trace_parser *parser)
> {
> - return (parser->idx != 0);
> + return !parser->fail && parser->idx != 0;
> }
>
> static inline bool trace_parser_cont(struct trace_parser *parser)
