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 EBC6B43DA5C; Tue, 21 Jul 2026 22:11:44 +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=1784671906; cv=none; b=fc2Lx02I5cEKCnysdEtCTYruz9M7aqI2FcbYZFcMD3uCznKhjqaenqV6/yXP1s3CFNLnMUABWNqs+VGm+kTDZDWseDbXCYOAXMwJWvfxNx2XwldCmxHh9gRwHVSq7112vJwDNVQttIMp/uJeHUDHhrzOLJIX8v+Ql/fUWCNdWiI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784671906; c=relaxed/simple; bh=x8WWxBbuK2UPG43PSTtQ5cXb8dhP7eNRD1NTq6QrFUk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FlYSuT4F2narC7M6Mj+ZnbkhQ/A1g3zl3lBH20FuZErhVZvyZ0ixAGE5nSnv2ppNsmIqJIterafqZG40FKeuUDjrX2ktgiS/l4FGfcbPLZBzYgsDk1xg9i6SM7Fh44fCnJfTrE3d5Xi/DFoJKWbQUNbTF6tbfmERmWq55OjE6HI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1t6jDpUn; 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="1t6jDpUn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C69FE1F000E9; Tue, 21 Jul 2026 22:11:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784671904; bh=sh+WjLCrYhprWfEcJCGd35Qnr2MstgwmaPzbb8I2czc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1t6jDpUnh9jpmtTZ9zYmACAoBf7XfIyev+Znrfyn/MFgvsrFKqgcXX4MfKK1QWuqC KuxnPylue7x24T35MkztEiTIUMOFjKMCIwhxHFq6wYce0IkvOrWTMQR6MenZ6zZTBS UP15U1fysCCkKwAoRI6GczvepqbYgHjXE4ByqWXw= 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 5.15 423/843] perf symbols: Add bounds checks to elf_read_build_id() note iteration Date: Tue, 21 Jul 2026 17:20:58 +0200 Message-ID: <20260721152415.550823259@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152405.946368001@linuxfoundation.org> References: <20260721152405.946368001@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 5.15-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 7029c71c57780a..d3bfa278df8141 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -540,10 +540,24 @@ 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