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
From an image on opengameart.org shared by rubberduck.
Source Firkin
The original enhanced with some gradients.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Submitted in a cream color, but you know how I like it.
Source Devin Holmes
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Just like your old suit, all striped and smooth.
Source Alex Berkowitz
Prismatic Groovy Concentric Background 5
Source GDJ
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Continuing the geometric trend, here is one more.
Source Mike Warner
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
One more sharp little tile for you. Subtle circles this time.
Source Blunia
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A brown metallic grid pattern layered on top of a dark fabric texture. It should look great when using as a tiled background on web pages, especially blogs.
Source V. Hartikainen
From a drawing in 'Bond Slaves. The story of a struggle.', Isabella Varley, 1893.
Source Firkin
This is a remix of "geometrical pattern 01".
Source Yamachem
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Here's a new background image for websites with a seamless pink texture. It should look beautiful with website themes where light pink background is needed. The background is seamless, therefore it should be used as a tiled background.
Source V. Hartikainen