If an extent has e_len set to zero, the kernel will oops with a
BUG_ON. Unfortunately, e2fsck wasn't catching this case. The kernel
needs to be fixed to notice this case and call ext4_error() instead of
failing an assertion check, but e2fsck should catch this case and
repair it (by deleting the errant extent).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Theodore Ts'o