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 C87DC1A726B; Mon, 14 Oct 2024 03:59:00 +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=1728878340; cv=none; b=VBbyGAjkpm+4u0bekvAzPbcHYvSw6aOW+Kj74bIIKtbb+dDF8lyFDCYvIEj9NFTE4616T7kay3dX/UWehiYmzd50c7sa2Xkv9UAvbwyDfXsuntMGKvOn2a4E3M0r3h6lpHH3C8HGbTJLeJg3hk3kWt81aDguoJ1mKIhy4hM1NVY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728878340; c=relaxed/simple; bh=iiNXBTXSYxUR7Njmep6gisphn1RKs2HVD7L0k2T+5a4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=CV2KAkNSKIdaZIahGolugj6UNvRXBqjVoGb+KuZwkqFNq3H9UFozA0ZINuUR1ham3NlizFiGwKzVPMFM0SN5H6zZ/tRpiuB0eEpjIDuhprBeSz0omf4OBpC0bamZyKYpiQrrR/OqHbOLRnKrtMtKgf6yCLpKyXB+AVCSGarsE7A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QEei9gPf; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QEei9gPf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70D2FC4CED0; Mon, 14 Oct 2024 03:58:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728878340; bh=iiNXBTXSYxUR7Njmep6gisphn1RKs2HVD7L0k2T+5a4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QEei9gPficzZsIvvUU3XlRqmthnd9JAU8MfvGSvCDeunK0fkiFkWAD7Dyxa6JL5FG CsmhjtVdb7BCxrZ/WLrB3vuSrpOYck7nwoAnz8aPkdTc/VdCZ6XaYzmC27NiSIS1k9 UG3i/1LOA31dshNsKDxvQgt1c28P/C6csdj0vmAVq6QqT7aXPyWgSTkUPR4r1yt4+I qAJscDHpwSqJoPoM5dHyIFV6pNHyL6O7zXy6Va0LrZQtKPWzdq2oLXwCOuhEsXjiVX X9xVoXh/uS6hWCVMyly/7WxuwPXdHBRRXKwNs7L6xBiXQqGXctzvzd30BEeUD8dhGo vYFyHZP+z3Hsg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Pali=20Roh=C3=A1r?= , Steve French , Sasha Levin , sfrench@samba.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org Subject: [PATCH AUTOSEL 6.1 07/10] cifs: Fix creating native symlinks pointing to current or parent directory Date: Sun, 13 Oct 2024 23:58:42 -0400 Message-ID: <20241014035848.2247549-7-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241014035848.2247549-1-sashal@kernel.org> References: <20241014035848.2247549-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.112 Content-Transfer-Encoding: 8bit From: Pali Rohár [ Upstream commit 63271b7d569fbe924bccc7dadc17d3d07a4e5f7a ] Calling 'ln -s . symlink' or 'ln -s .. symlink' creates symlink pointing to some object name which ends with U+F029 unicode codepoint. This is because trailing dot in the object name is replaced by non-ASCII unicode codepoint. So Linux SMB client currently is not able to create native symlink pointing to current or parent directory on Windows SMB server which can be read by either on local Windows server or by any other SMB client which does not implement compatible-reverse character replacement. Fix this problem in cifsConvertToUTF16() function which is doing that character replacement. Function comment already says that it does not need to handle special cases '.' and '..', but after introduction of native symlinks in reparse point form, this handling is needed. Note that this change depends on the previous change "cifs: Improve creating native symlinks pointing to directory". Signed-off-by: Pali Rohár Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/client/cifs_unicode.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/fs/smb/client/cifs_unicode.c b/fs/smb/client/cifs_unicode.c index e7582dd791794..53f862a9c03cc 100644 --- a/fs/smb/client/cifs_unicode.c +++ b/fs/smb/client/cifs_unicode.c @@ -485,10 +485,21 @@ cifsConvertToUTF16(__le16 *target, const char *source, int srclen, /** * Remap spaces and periods found at the end of every * component of the path. The special cases of '.' and - * '..' do not need to be dealt with explicitly because - * they are addressed in namei.c:link_path_walk(). + * '..' are need to be handled because of symlinks. + * They are treated as non-end-of-string to avoid + * remapping and breaking symlinks pointing to . or .. **/ - if ((i == srclen - 1) || (source[i+1] == '\\')) + if ((i == 0 || source[i-1] == '\\') && + source[i] == '.' && + (i == srclen-1 || source[i+1] == '\\')) + end_of_string = false; /* "." case */ + else if (i >= 1 && + (i == 1 || source[i-2] == '\\') && + source[i-1] == '.' && + source[i] == '.' && + (i == srclen-1 || source[i+1] == '\\')) + end_of_string = false; /* ".." case */ + else if ((i == srclen - 1) || (source[i+1] == '\\')) end_of_string = true; else end_of_string = false; -- 2.43.0