Commit 9a571c1e authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracing/probes: Fix to set arg size and fmt after setting type from BTF 

Since the BTF type setting updates probe_arg::type, the type size
calculation and setting print-fmt should be done after that.
Without this fix, the argument size and print-fmt can be wrong.

Link: https://lore.kernel.org/all/170602218196.215583.6417859469540955777.stgit@devnote2/



Fixes: b576e097 ("tracing/probes: Support function parameters if BTF is available")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
parent 8c427cc2

kernel/trace/trace_probe.c

+13 −12
Original line number Diff line number Diff line
@@ -1172,18 +1172,6 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, 
		trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_TYPE);

		goto out;

	}

	parg->offset = *size;

	*size += parg->type->size * (parg->count ?: 1);



	ret = -ENOMEM;

	if (parg->count) {

		len = strlen(parg->type->fmttype) + 6;

		parg->fmt = kmalloc(len, GFP_KERNEL);

		if (!parg->fmt)

			goto out;

		snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype,

			 parg->count);

	}



	code = tmp = kcalloc(FETCH_INSN_MAX, sizeof(*code), GFP_KERNEL);

	if (!code)
@@ -1207,6 +1195,19 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, 
				goto fail;

		}

	}

	parg->offset = *size;

	*size += parg->type->size * (parg->count ?: 1);



	if (parg->count) {

		len = strlen(parg->type->fmttype) + 6;

		parg->fmt = kmalloc(len, GFP_KERNEL);

		if (!parg->fmt) {

			ret = -ENOMEM;

			goto out;

		}

		snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype,

			 parg->count);

	}



	ret = -EINVAL;

	/* Store operation */