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
The name is totally random, but hey, it sounds good.
Source Atle Mo
More leather, and this time it’s bigger! You know, in case you need that.
Source Elemis
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A seamless pattern formed from miutopia's cakes on a tablecloth.
Source Firkin
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Embossed lines and squares with subtle highlights.
Source Alex Parker
A version without colours blended together to give a different look.
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
No idea what Nistri means, but it’s a crisp little pattern nonetheless.
Source Markus Reiter
A bit of scratched up grayness. Always good.
Source Dmitry
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
The image a seamless pattern of a wire-mesh fence.I want you to use this pattern as a lower layer.
Source Yamachem
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Inspired by the B&O Play, I had to make this pattern.
Source Atle Mo
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein