Re: [PATCH 4.9-5.8] Convert trailing spaces and periods in path components

[Greg KH <gregkh@linuxfoundation.org>]

On Sat, Oct 17, 2020 at 03:28:39PM +0000, Boris Protopopov wrote:
> When converting trailing spaces and periods in paths, do so
> for every component of the path, not just the last component.
> If the conversion is not done for every path component, then
> subsequent operations in directories with trailing spaces or
> periods (e.g. create(), mkdir()) will fail with ENOENT. This
> is because on the server, the directory will have a special
> symbol in its name, and the client needs to provide the same.
> 
> Cc: <stable@vger.kernel.org> # 4.9.x-5.8.x
> Signed-off-by: Boris Protopopov <pboris@amazon.com>
> ---
>  fs/cifs/cifs_unicode.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/cifs/cifs_unicode.c b/fs/cifs/cifs_unicode.c
> index 498777d859eb..9bd03a231032 100644
> --- a/fs/cifs/cifs_unicode.c
> +++ b/fs/cifs/cifs_unicode.c
> @@ -488,7 +488,13 @@ cifsConvertToUTF16(__le16 *target, const char *source, int srclen,
>  		else if (map_chars == SFM_MAP_UNI_RSVD) {
>  			bool end_of_string;
>  
> -			if (i == srclen - 1)
> +			/**
> +			 * 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().
> +			 **/
> +			if ((i == srclen - 1) || (source[i+1] == '\\'))
>  				end_of_string = true;
>  			else
>  				end_of_string = false;
> -- 
> 2.18.4
> 

What is the git commit id of this in Linus's tree?

thanks,

greg k-h