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 A8C54188013; Tue, 30 Jul 2024 16:45:08 +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=1722357908; cv=none; b=XBCReR18DKX5RRUdupeLvmT9HNEkYYbS61d3e2U6sv36Ry4/Uqxp39DHARLUFZGR/GbECqzPL3Wwr5qoHWfaDU/NH2tywVZ71nS8vbwuaeI/f+Tln3shT9CZBGaea34inP5JNZ9vu51xgeBm78RBuGp/ij0mc21LF/zRn7ZZT3c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722357908; c=relaxed/simple; bh=gdJnLC/QNTTYUmK/PY/jMRc6JlwKtg0/+RzwtYSKD9g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dzOa3zX5R4RbYGPfVMEDOkUplFHxy38SJyCProR9KZ93PwCZDURHDQWoByhZZlhloiS2kGtiSU4naI/Vw62Harse0kvkglhbI0y4DfUq7GbZWQZz6Bk2l8NhM4utgGSUikEg98zF4uMRXAz0UsXttsjMvPGuukSh4cm/HamNf/I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=slagj+fk; 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="slagj+fk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 180CCC32782; Tue, 30 Jul 2024 16:45:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1722357908; bh=gdJnLC/QNTTYUmK/PY/jMRc6JlwKtg0/+RzwtYSKD9g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=slagj+fksTigVnz7JayMFvvvGHGQ62CNq1vPEz4hXloFfXAlatzzs/hUURXb0Ecuv 9tR8sSRzg1whjbvzFZh3WlCKbUMVWILnbGxqzHN+mVcgWJpMXL3ZtiJq91oht6rqdR yyNE6sUePSYYCqI3IzviJs8n5XEr4YrGrYs3HDqI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zijun Hu , Lk Sii Subject: [PATCH 6.1 338/440] kobject_uevent: Fix OOB access within zap_modalias_env() Date: Tue, 30 Jul 2024 17:49:31 +0200 Message-ID: <20240730151629.019122951@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240730151615.753688326@linuxfoundation.org> References: <20240730151615.753688326@linuxfoundation.org> User-Agent: quilt/0.67 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zijun Hu commit dd6e9894b451e7c85cceb8e9dc5432679a70e7dc upstream. zap_modalias_env() wrongly calculates size of memory block to move, so will cause OOB memory access issue if variable MODALIAS is not the last one within its @env parameter, fixed by correcting size to memmove. Fixes: 9b3fa47d4a76 ("kobject: fix suppressing modalias in uevents delivered over netlink") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu Reviewed-by: Lk Sii Link: https://lore.kernel.org/r/1717074877-11352-1-git-send-email-quic_zijuhu@quicinc.com Signed-off-by: Greg Kroah-Hartman --- lib/kobject_uevent.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -432,8 +432,23 @@ static void zap_modalias_env(struct kobj len = strlen(env->envp[i]) + 1; if (i != env->envp_idx - 1) { + /* @env->envp[] contains pointers to @env->buf[] + * with @env->buflen chars, and we are removing + * variable MODALIAS here pointed by @env->envp[i] + * with length @len as shown below: + * + * 0 @env->buf[] @env->buflen + * --------------------------------------------- + * ^ ^ ^ ^ + * | |-> @len <-| target block | + * @env->envp[0] @env->envp[i] @env->envp[i + 1] + * + * so the "target block" indicated above is moved + * backward by @len, and its right size is + * @env->buflen - (@env->envp[i + 1] - @env->envp[0]). + */ memmove(env->envp[i], env->envp[i + 1], - env->buflen - len); + env->buflen - (env->envp[i + 1] - env->envp[0])); for (j = i; j < env->envp_idx - 1; j++) env->envp[j] = env->envp[j + 1] - len;