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 0FC021A7065; Thu, 15 Aug 2024 13:32:57 +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=1723728778; cv=none; b=nfVpWEpkDDdAgDMUClUBp9gGW81nJ72QSW5s0gj1K4rLhLISldQOKeI7Te+2UrGDPF3tjmhYVo5CCU0LcwZCe9pCyFqhw1d4pgpnffu/XDQUEEbFg33FnupCuwvVirVTiCJzq8dQP940u5au6BVH8NugccaHqnZmSDn67twGHu8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723728778; c=relaxed/simple; bh=baVIuH+eR6LS8WEEaQ2yxNMjOXgcRX4vowY5hEzPpww=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Og25mp6NNQDYdluq+rqROvSySiQWex9osQPDQZtfW7xEl3ztZbWtDHoBlMaV+wbuGcHasdAkmYSNFMmv1COoizj7LXIjWQ//XpJIOM9sZCzn8AviJGG78sv36E0C0zVg75YZ0ImHfrM1BfwcMMpM0xXjmpLYBbVIPW+pPky6hDw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uOQ3Fphv; 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="uOQ3Fphv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 236DEC32786; Thu, 15 Aug 2024 13:32:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723728777; bh=baVIuH+eR6LS8WEEaQ2yxNMjOXgcRX4vowY5hEzPpww=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uOQ3Fphvd6+QkEN648BadSyftws6BWXCYyagNra9EStekbpR9AEYMEkxJfovCHMl3 iSoULNSJZQxJmoCXDfR0vFuRdgScXIWdPoqk/P4T3QIglKXWT43XgzltO/tuo+Ub3C E0nQsnwgYX7MbELhotHy8MvIPJbsJYQwinUu1bSA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 4.19 105/196] mISDN: Fix a use after free in hfcmulti_tx() Date: Thu, 15 Aug 2024 15:23:42 +0200 Message-ID: <20240815131856.099245264@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240815131852.063866671@linuxfoundation.org> References: <20240815131852.063866671@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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter [ Upstream commit 61ab751451f5ebd0b98e02276a44e23a10110402 ] Don't dereference *sp after calling dev_kfree_skb(*sp). Fixes: af69fb3a8ffa ("Add mISDN HFC multiport driver") Signed-off-by: Dan Carpenter Reviewed-by: Simon Horman Link: https://patch.msgid.link/8be65f5a-c2dd-4ba0-8a10-bfe5980b8cfb@stanley.mountain Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/isdn/hardware/mISDN/hfcmulti.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c index 60b3a4aabe6b8..9010d5ca3cd53 100644 --- a/drivers/isdn/hardware/mISDN/hfcmulti.c +++ b/drivers/isdn/hardware/mISDN/hfcmulti.c @@ -1945,7 +1945,7 @@ hfcmulti_dtmf(struct hfc_multi *hc) static void hfcmulti_tx(struct hfc_multi *hc, int ch) { - int i, ii, temp, len = 0; + int i, ii, temp, tmp_len, len = 0; int Zspace, z1, z2; /* must be int for calculation */ int Fspace, f1, f2; u_char *d; @@ -2166,14 +2166,15 @@ hfcmulti_tx(struct hfc_multi *hc, int ch) HFC_wait_nodebug(hc); } + tmp_len = (*sp)->len; dev_kfree_skb(*sp); /* check for next frame */ if (bch && get_next_bframe(bch)) { - len = (*sp)->len; + len = tmp_len; goto next_frame; } if (dch && get_next_dframe(dch)) { - len = (*sp)->len; + len = tmp_len; goto next_frame; } -- 2.43.0