In the Linux kernel, the following vulnerability has been resolved:
f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set()
f2fs_xattr_advise_set() calls inode_owner_or_capable() with &nop_mnt_idmap
before allowing the "system.advise" xattr to be set, instead of the idmap
that the VFS passes to the ->set() handler.
f2fs supports idmapped mounts, so on such a mount this checks the caller's
fsuid against the unmapped on-disk owner rather than the mapped owner: the
actual owner can be wrongly denied with -EPERM and an unrelated caller
wrongly allowed. Pass the handler's idmap instead.
Ссылки 5
https://git.kernel.org/stable/c/3b681229e9f8fb1dd29bc65983bf3c87779e4ca3
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/a54ffce4637acb0db8e695188a6c7f99f14c3576
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/ab31e3b774f5d06b4489cef6c297b48c47c9dcbd
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/c3e2692c7a58e0bdb84bd658d827e89dcecea3ad
416baaa9-dc9f-4396-8d5f-8c081fb06d67