[PATCH 0/3] ocfs2: stop BUG_ON crashes in suballoc invalid-dinode paths

[ZhengYuan Huang <gality369@gmail.com>]

commit 10995aa2451a ("ocfs2: Morph the haphazard
OCFS2_IS_VALID_DINODE() checks.") converted several OCFS2 dinode
corruption checks from graceful error handling to BUG_ON() under the
assumption that every caller only sees validated inode buffers.

That assumption does not always hold for JBD-managed buffers. The common
inode read path can still hand suballoc code an invalid dinode, which turns
crafted filesystem corruption into a kernel panic instead of a normal OCFS2
filesystem error.

This series restores graceful corruption handling at the three
independently reachable BUG_ON() sites in fs/ocfs2/suballoc.c:

1. reserve_suballoc_bits()
2. claim_suballoc_bits()
3. _ocfs2_free_suballoc_bits()

The series is split per crash site so each patch fixes one bug. A broader
follow-up could harden structural validation for JBD-managed inode reads,
but that change touches a much wider read-side contract and is kept out of
scope here.

ZhengYuan Huang (3):
  ocfs2: handle invalid dinode in reserve_suballoc_bits
  ocfs2: handle invalid dinode in claim_suballoc_bits
  ocfs2: handle invalid dinode in _ocfs2_free_suballoc_bits

 fs/ocfs2/suballoc.c | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

-- 
2.43.0