From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794558556; b=v/C6PuMoixLeK7UURDoRAT9NFOhMXYwJemYGeWSxyWu2BQchg0wxGwdFdexNO9D71lrO q9FCquwvITXXB0kwwZhBGLzFbbBPc+KwAvnwRbJKFAkMsx+24zsosjsROqcK3beKO+GdC UawYfEXujKihVpJ3x77CCeYAABOGP9Nu0ByN+gLpReLMd+zzzOnR7ghiDxWWkwOKrXqru AQTNrcE+BbEznMY/jQG1BhHOBJ8SZPZA74w3JvPOGjnoNzRDhtJ7ccL6JfqnLJMuLr7SO hhEeBldXLfCntr4lknjErOnoaafR24YEHreYPGSgEw+D5xbkGFjqe7YjGn6U9OBzqYA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794558556; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=DZV4gQZAUJNcBQXwAOUQAHIyYUTe+7KEUuKIehGNzIM=; b=AVzGWx+qoqxXeuCd5J5hjooebxnk7aTglnQTF7ReN7ZFaYBmiS8mL0epkF3vIhNVkJLH YXxAUcpBftW7x6+CtjQERgxxHkxtGeSAJri5sANpsndPe23rPjM18okxuF9FDM6VSQkQB laVNQu8fIn4bcbidOH+I4Y6nk6v4OfPAcknEx0IK1k5Kzniadt+qsUXcxv/T64xCtJtB4 98wc2jMnUabk7kSJ3ZtCLLfG3jQBr/bztpgfCzU29LOchF+4jGf42y3CMeUsBhp0l5vVF Q9G42oY7ARe8VGH/JQym3u+3e+dnkV8OkQ43CJHeYaUNhY8tBxZebZPU/eoJ06HRgzg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BV4smHPq; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CDE5960A2608; Fri, 13 Nov 2026 08:29:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BV4smHPq Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9ED811F000C4; Fri, 13 Nov 2026 08:29:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794558556; bh=DZV4gQZAUJNcBQXwAOUQAHIyYUTe+7KEUuKIehGNzIM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BV4smHPqoo9DWtB6lF8WJz+F01KWAtz4gbPNcHmI5+tBdrRHlrkoUFrQfJMCOJdXb 2QQ5oImmAmKbgxyr7IXaK2x1aWxEjnp1Y83px0+ZEhsGq9RVZ6LlaKd4gPESu5w12P NjXWPPvInr8/+RKKH7VLs5HU9Y1euixhyHtQU2ctxnIRVJmbta+7jBbWrGspDT8jrI f2kOaNcR8mIeGxoTgV+cVpwP7HwP5OKWtVn0MRcYQaQaZrBGKAiyw5V33NpXOP4e0B JraYuAc115AblePYPwAUsA7ZFePWWuesY3GuXL6wOhr8PX75//jW6w+FWtYZYLK9jH o6FOVSzUJhOSQ== From: "Masami Hiramatsu (Google)" To: Steven Rostedt , Masami Hiramatsu Cc: Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH v3 08/13] tracing/probes: Reject array count on non-dereference string sources Date: Fri, 13 Nov 2026 17:29:13 +0900 Message-ID: <179455855309.403392.4197028577158545202.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <179455847934.403392.15146485751358774349.stgit@devnote2> References: <179455847934.403392.15146485751358774349.stgit@devnote2> User-Agent: StGit/0.19 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit From: Masami Hiramatsu (Google) The runtime array loop (FETCH_OP_LP_ARRAY) for string types requires a preceding memory dereference instruction so it can advance the pointer address on each iteration. Non-dereference string sources such as $comm, immediate strings, and eprobe event fields cannot be indexed as pointer arrays, but finalize_fetch_insn() still accepts an array count on them and emits an invalid FETCH_OP_LP_ARRAY sequence. Reject string array counts when the preceding operation is not a memory dereference. Fixes: 40b53b771806 ("tracing: probeevent: Add array type support") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) --- Changes in v2: - Add Fixes and Cc: stable tags. --- kernel/trace/trace_probe.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index eee5353ef5c7..9c789ca316b7 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -1990,6 +1990,12 @@ static int finalize_fetch_insn(struct fetch_insn *code, * For the symstr, it doesn't need to dereference, thus * it just get the value. */ + if (parg->count && (code->op != FETCH_OP_DEREF && + code->op != FETCH_OP_UDEREF)) { + trace_probe_log_err(ctx->offset + type_offset, + BAD_STRING); + return -EINVAL; + } code++; if (code->op != FETCH_OP_NOP) { trace_probe_log_err(ctx->offset, TOO_MANY_OPS);