Comment 2 for bug 2041670

Created attachment 305300
C reproducer of the problem. Run it on a tmpfs file system mounted on /mnt/tmpfs

creating a file on tmpfs with open(filename, O_RDWR | O_DIRECT | O_CREAT, 0666) reports an open failure error EINVAL, but still creates the file. The file should not be created if we hit such an error.

Tested this on 6.6.0-rc7 and 6.1.0-13 mainline kernels, x86-64.

mkdir /mnt/tmpfs
sudo mount -t tmpfs -o size=1G,nr_inodes=10k,mode=777 tmpfs /mnt/tmpfs
sudo chmod 666 /mnt/tmpfs

Run the attached program. It reports an open failure (errno 22, EINVAL) but still manages to create the file.

Note this was original discovered by running stress-ng on tmpfs with the open stressor: stress-ng --open 1