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Both chains are terminated by ~0, but the next block values are image-controlled. A crafted filesystem can create a cycle in either chain. Lookup of a missing directory entry or read of a file with a cyclic extent continuation then loops in the kernel. This series detects cycles in both metadata chains. I verified the fixes with crafted OMFS images: - directory sibling self-cycle: unpatched kernel timed out after "statting /mnt/missing"; patched kernel returned ELOOP. - file extent continuation self-cycle: unpatched kernel timed out after "reading /mnt/loopfile"; patched kernel returned from read with EIO. Valid directory and file images continued to behave normally. 이상호 (2): omfs: detect directory sibling chain cycles omfs: detect file extent chain cycles fs/omfs/dir.c | 64 +++++++++++++++++++++++++++++++++++++++- fs/omfs/file.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 141 insertions(+), 2 deletions(-) -- 2.43.0