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 3193935E1D8; Tue, 21 Jul 2026 18:08:53 +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=1784657334; cv=none; b=I8dfhCNXS71IqAiLsaqUT6ZxSrx6el52Tfg/wvGyvgYLAr3J4jFISMX5mYLvClHMiwESMVaKgb8bGtGI+PNBAl1xddB40K72orqoL/++KbVmJPGqQ/Bg2iKNX6GR5x87EBlgRMzLowKY0ujvQ3FXVBAuj5fy/STfTSWfcT9NLm8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784657334; c=relaxed/simple; bh=nYzpTVN7ozZlikgemU8H4obdidDiN4RfRY1JVI4TC8c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cIKDIR/FUBaNd11RPVEwaqc7OsrmSCNKgIJNzix+6XaOXVfGREetmKjI793lVpvY4lOgnGnbOiFumFTUy24QPagiLY1rXlSmNy0K5Z6XfqHT7u9xjwy/4/y8RrBum3PEUB5WtdnyL24QYkUGR6Hu5BzAOsED3EEjuTuNNY5l38A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=rTFuNnx6; 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="rTFuNnx6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 786CC1F000E9; Tue, 21 Jul 2026 18:08:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784657333; bh=3HoPT8dbgrEuNuhFjts9fkFToK7hhh6njSOeP3CcGl8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=rTFuNnx676jANt/YNhUsEVLRogR5mUvUFFnhaBb7NxyC+BAr0nSAkRMo2LpexoS4Z t2gdnjqVQP4bF//fyOWdAHzwr9n00WXMoSMqRDaVaY+4KcJVmoubMgYmxLf3MCLb14 3ur2NqyBv3hxeWuZxRg05rHUiJxUeBMP7mWkcs9Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, sashiko-bot , Namhyung Kim , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 6.18 0725/1611] perf symbols: Add bounds checks to elf_read_build_id() note iteration Date: Tue, 21 Jul 2026 17:14:01 +0200 Message-ID: <20260721152531.689421633@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152514.750365251@linuxfoundation.org> References: <20260721152514.750365251@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnaldo Carvalho de Melo [ Upstream commit acc56d3941fc2997a5a21ea9233a8ac3d87c4f2f ] elf_read_build_id() iterates ELF notes using pointer arithmetic driven by n_namesz and n_descsz from the note headers. Neither the note header read nor the subsequent name/desc advances are checked against the section boundary. A malformed ELF file with oversized note sizes causes out-of-bounds reads past the section data buffer. Add two bounds checks: verify the note header fits within the remaining section data, and verify that namesz + descsz (after alignment) fits before advancing the pointer. Fixes: fd7a346ea292074e ("perf symbols: Filename__read_build_id should look at .notes section too") Reported-by: sashiko-bot Cc: Namhyung Kim Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/symbol-elf.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index f96aec292ade23..107e10006cd1c7 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -836,10 +836,24 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size) ptr = data->d_buf; while (ptr < (data->d_buf + data->d_size)) { GElf_Nhdr *nhdr = ptr; - size_t namesz = NOTE_ALIGN(nhdr->n_namesz), - descsz = NOTE_ALIGN(nhdr->n_descsz); + size_t namesz, descsz, remaining; const char *name; + /* ensure the note header fits within the section */ + if (ptr + sizeof(*nhdr) > data->d_buf + data->d_size) + break; + + namesz = NOTE_ALIGN(nhdr->n_namesz); + descsz = NOTE_ALIGN(nhdr->n_descsz); + + /* validate individually to avoid size_t overflow on 32-bit */ + remaining = data->d_buf + data->d_size - ptr - sizeof(*nhdr); + if (namesz > remaining || descsz > remaining - namesz) { + pr_warning("%s: oversized note: n_namesz=%u, n_descsz=%u\n", + __func__, nhdr->n_namesz, nhdr->n_descsz); + break; + } + ptr += sizeof(*nhdr); name = ptr; ptr += namesz; -- 2.53.0