From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 08AE732252B; Mon, 18 Aug 2025 13:36:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755524182; cv=none; b=KDuq/h3/37vthpidpXtef8CFWrmgjVkcqHTh0vUfTjPZmExKMX4iBrbqNyKrAwVeXPRHDDtYnBC5+5+6R72RUG6HR+jXcZqMOCngtGHzv7dJWAUSbD+UXOzMJZElynISc9MmC/C95si+7DiRS33E1PitI0KEJ3zoT71GSg4ngjQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755524182; c=relaxed/simple; bh=LCE5SOKHIGIquMYkqPxvhCX6pZ5ofsqbtnm106qhzn4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S0i2A25nhIDEmExfnEL1XY7+P/iEfw3YnxzNe2k6jJzqfDRe96uw0MLYVxd00IX7cPutj9+DIiRTSJUozdur8+qSF4AA3YmwmJ104clEVpwYDjPPbezMJp2WMjXToWvoFW89g7qrCeVoKpvtN2JJJjDZHhxqZTvtvze9E6Z+JBM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qFDZ9ccr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qFDZ9ccr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85AE9C4CEEB; Mon, 18 Aug 2025 13:36:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755524181; bh=LCE5SOKHIGIquMYkqPxvhCX6pZ5ofsqbtnm106qhzn4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qFDZ9ccrELu1byGYRxXNhRdiQbOWLFhAxDCSV2+kZ0/aDflYVvReOWd5mD8ra97JE y5h8HARDmF6v0DZQgytsF5/WJXDf1g/61PEIHH8x0iekGaLsS1bNF0X++aTvz4VKrv 3h+4DFERpfpalDXZ9tuPvc0B6nQSb/jNc5Hw7x3U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Petr Pavlu , Daniel Gomez , Sasha Levin Subject: [PATCH 6.15 391/515] module: Prevent silent truncation of module name in delete_module(2) Date: Mon, 18 Aug 2025 14:46:17 +0200 Message-ID: <20250818124513.469136550@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250818124458.334548733@linuxfoundation.org> References: <20250818124458.334548733@linuxfoundation.org> User-Agent: quilt/0.68 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 6.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Petr Pavlu [ Upstream commit a6323bd4e611567913e23df5b58f2d4e4da06789 ] Passing a module name longer than MODULE_NAME_LEN to the delete_module syscall results in its silent truncation. This really isn't much of a problem in practice, but it could theoretically lead to the removal of an incorrect module. It is more sensible to return ENAMETOOLONG or ENOENT in such a case. Update the syscall to return ENOENT, as documented in the delete_module(2) man page to mean "No module by that name exists." This is appropriate because a module with a name longer than MODULE_NAME_LEN cannot be loaded in the first place. Signed-off-by: Petr Pavlu Reviewed-by: Daniel Gomez Link: https://lore.kernel.org/r/20250630143535.267745-2-petr.pavlu@suse.com Signed-off-by: Daniel Gomez Signed-off-by: Sasha Levin --- kernel/module/main.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/module/main.c b/kernel/module/main.c index 05da78b6a6c1..4e4e0fd11dde 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -727,14 +727,16 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, struct module *mod; char name[MODULE_NAME_LEN]; char buf[MODULE_FLAGS_BUF_SIZE]; - int ret, forced = 0; + int ret, len, forced = 0; if (!capable(CAP_SYS_MODULE) || modules_disabled) return -EPERM; - if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) - return -EFAULT; - name[MODULE_NAME_LEN-1] = '\0'; + len = strncpy_from_user(name, name_user, MODULE_NAME_LEN); + if (len == 0 || len == MODULE_NAME_LEN) + return -ENOENT; + if (len < 0) + return len; audit_log_kern_module(name); -- 2.39.5