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 30A6D79D8; Sat, 30 Dec 2023 12:05:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="u2FtGz3o" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 596C9C433C7; Sat, 30 Dec 2023 12:05:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1703937958; bh=uNWs5a0NcNvtoMfbLEhsWE3LXwZ41jj+OmVeXZ2jNYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=u2FtGz3oxW4s1Hi753ZLifmQUNhbGL7ZpkloOuZiDkqJAyBEkUI68YL4Ep5v87IhV zAJzCGo+K+Nlk7XgyGx/ys21yCU/5P0mjDOqIfC3fteJ9d9v1tRoc5icIEzkmR+ylD sAOYKV2xwi6PlwlRmC0Nx5GH7Lud/GNi9E6pEkKo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, j51569436@gmail.com, "Paulo Alcantara (SUSE)" , Steve French Subject: [PATCH 6.6 128/156] smb: client: fix OOB in smbCalcSize() Date: Sat, 30 Dec 2023 11:59:42 +0000 Message-ID: <20231230115816.549764772@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231230115812.333117904@linuxfoundation.org> References: <20231230115812.333117904@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paulo Alcantara commit b35858b3786ddbb56e1c35138ba25d6adf8d0bef upstream. Validate @smb->WordCount to avoid reading off the end of @smb and thus causing the following KASAN splat: BUG: KASAN: slab-out-of-bounds in smbCalcSize+0x32/0x40 [cifs] Read of size 2 at addr ffff88801c024ec5 by task cifsd/1328 CPU: 1 PID: 1328 Comm: cifsd Not tainted 6.7.0-rc5 #9 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 Call Trace: dump_stack_lvl+0x4a/0x80 print_report+0xcf/0x650 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? __phys_addr+0x46/0x90 kasan_report+0xd8/0x110 ? smbCalcSize+0x32/0x40 [cifs] ? smbCalcSize+0x32/0x40 [cifs] kasan_check_range+0x105/0x1b0 smbCalcSize+0x32/0x40 [cifs] checkSMB+0x162/0x370 [cifs] ? __pfx_checkSMB+0x10/0x10 [cifs] cifs_handle_standard+0xbc/0x2f0 [cifs] ? srso_alias_return_thunk+0x5/0xfbef5 cifs_demultiplex_thread+0xed1/0x1360 [cifs] ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] ? srso_alias_return_thunk+0x5/0xfbef5 ? lockdep_hardirqs_on_prepare+0x136/0x210 ? __pfx_lock_release+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? mark_held_locks+0x1a/0x90 ? lockdep_hardirqs_on_prepare+0x136/0x210 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? __kthread_parkme+0xce/0xf0 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] kthread+0x18d/0x1d0 ? kthread+0xdb/0x1d0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 This fixes CVE-2023-6606. Reported-by: j51569436@gmail.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218218 Cc: stable@vger.kernel.org Signed-off-by: Paulo Alcantara (SUSE) Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/smb/client/misc.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/fs/smb/client/misc.c +++ b/fs/smb/client/misc.c @@ -363,6 +363,10 @@ checkSMB(char *buf, unsigned int total_r cifs_dbg(VFS, "Length less than smb header size\n"); } return -EIO; + } else if (total_read < sizeof(*smb) + 2 * smb->WordCount) { + cifs_dbg(VFS, "%s: can't read BCC due to invalid WordCount(%u)\n", + __func__, smb->WordCount); + return -EIO; } /* otherwise, there is enough to get to the BCC */