From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFEC333A033; Thu, 2 Jul 2026 16:39:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783010360; cv=none; b=bwxxHitVg2Os40MJuY5c03iZ5qCa0hSNkIYiMyede1qJtxKY+Vigx1NDGb0GGNsPD0g6NoEvY1LbD2AayVtI78Sp2NQNZScFufsUnXLkvQLWQo1ba8pkhnVz01PQF55IVzeNqYgd+SETlahvIjNFn6DOJrX2lQp7I5qhDnrcTzE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783010360; c=relaxed/simple; bh=66zBd/QzTqPs1iOKjlgqCHKnZCVr+6TMF1Y3vbzCMiQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LqlBo/1aBKUmraQ8iJJNmzGSWF1lZvC0fEjLBCtHtWM0UAyx7X0A1Tzty7BYDzvMTPBtoOOpQk2iTVHi2x8USwhlHHHqjlyN5+yWRaA8IPYr8IXgJGAX3jlodOY26zT1+HCtBBnsrB0q6+lKQkjnFUjgNguc+zWo6lz+z5K6E30= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dYqTbs8Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="dYqTbs8Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48A751F000E9; Thu, 2 Jul 2026 16:39:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1783010358; bh=mX/YclM4Uwk6pX22Ou+ktpF3bcG2BH+cXG2OYJlXCbs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dYqTbs8Zot9kpDCYFiFtto6lG95ZpOUsrTbVnSRkKss/ZB0Twbzs51r5tQteJ2bDT i+ynZfygtIsemr7AYotUKO+TA89TRqqwUKT4VD3Bs4Z8eIEjcbdgmu2kp+l9ZP3UWh Z27hIy42+0YSbfgKmZBfSwXf+Vipe5aR2rMs8BV4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Masahiro Yamada , Catalin Marinas , Will Deacon , "Arnd Bergmann" , Nathan Chancellor , Mark Brown , "Steven Rostedt (Google)" , Andrey Grodzovsky Subject: [PATCH 6.12 080/204] ftrace: Check against is_kernel_text() instead of kaslr_offset() Date: Thu, 2 Jul 2026 18:18:57 +0200 Message-ID: <20260702155120.344150487@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260702155118.667618796@linuxfoundation.org> References: <20260702155118.667618796@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt [ Upstream commit da0f622b344be769ed61e7c1caf95cd0cdb47964 ] As kaslr_offset() is architecture dependent and also may not be defined by all architectures, when zeroing out unused weak functions, do not check against kaslr_offset(), but instead check if the address is within the kernel text sections. If KASLR added a shift to the zeroed out function, it would still not be located in the kernel text. This is a more robust way to test if the text is valid or not. Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Masahiro Yamada Cc: Catalin Marinas Cc: Will Deacon Cc: "Arnd Bergmann" Link: https://lore.kernel.org/20250225182054.471759017@goodmis.org Fixes: ef378c3b8233 ("scripts/sorttable: Zero out weak functions in mcount_loc table") Reported-by: Nathan Chancellor Reported-by: Mark Brown Tested-by: Nathan Chancellor Closes: https://lore.kernel.org/all/20250224180805.GA1536711@ax162/ Closes: https://lore.kernel.org/all/5225b07b-a9b2-4558-9d5f-aa60b19f6317@sirena.org.uk/ Signed-off-by: Steven Rostedt (Google) Signed-off-by: Andrey Grodzovsky Signed-off-by: Greg Kroah-Hartman --- kernel/trace/ftrace.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7051,7 +7051,6 @@ static int ftrace_process_locs(struct mo unsigned long count; unsigned long *p; unsigned long addr; - unsigned long kaslr; unsigned long flags = 0; /* Shut up gcc */ unsigned long pages; int ret = -ENOMEM; @@ -7101,9 +7100,6 @@ static int ftrace_process_locs(struct mo ftrace_pages->next = start_pg; } - /* For zeroed locations that were shifted for core kernel */ - kaslr = !mod ? kaslr_offset() : 0; - p = start; pg = start_pg; while (p < end) { @@ -7117,7 +7113,18 @@ static int ftrace_process_locs(struct mo * object files to satisfy alignments. * Skip any NULL pointers. */ - if (!addr || addr == kaslr) { + if (!addr) { + skipped++; + continue; + } + + /* + * If this is core kernel, make sure the address is in core + * or inittext, as weak functions get zeroed and KASLR can + * move them to something other than zero. It just will not + * move it to an area where kernel text is. + */ + if (!mod && !(is_kernel_text(addr) || is_kernel_inittext(addr))) { skipped++; continue; }