In the Linux kernel, the following vulnerability has been resolved:

erofs: handle NONHEAD !delta[1] lclusters gracefully

syzbot reported a WARNING in iomap_iter_done:
 iomap_fiemap+0x73b/0x9b0 fs/iomap/fiemap.c:80
 ioctl_fiemap fs/ioctl.c:220 [inline]

Generally, NONHEAD lclusters won't have delta[1]==0, except for crafted
images and filesystems created by pre-1.0 mkfs versions.

Previously, it would immediately bail out if delta[1]==0, which led to
inadequate decompressed lengths (thus FIEMAP is impacted).  Treat it as
delta[1]=1 to work around these legacy mkfs versions.

`lclusterbits > 14` is illegal for compact indexes, error out too.

https://git.kernel.org/stable/c/0bc8061ffc733a0a246b8689b2d32a3e9204f43c

https://git.kernel.org/stable/c/480c6c7b55aeacac800bc2a0d321ff53273045e5

https://git.kernel.org/stable/c/daaf68fef4b2ff97928227630021d37b27a96655

https://git.kernel.org/stable/c/f466641debcbea8bdf78d1b63a6270aadf9301bf