Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
Colorful Floral Background 3 No Black
Source GDJ
Background Wall, Art Abstract, Watercolor Vintage style CC0 texture.
Source Ractapopulous
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A bit of scratched up grayness. Always good.
Source Dmitry
From a drawing in 'A Life Interest', Mrs Alexander, 1888.
Source Firkin
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
Colourful background achieved with gradient fills.
Source Firkin
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin