Commits
Darrick J. Wong committed aafe12cee0b
xfs: don't trip over negative free space in xfs_reserve_blocks If we somehow end up with a filesystem that has fewer free blocks than the blocks set aside to avoid ENOSPC deadlocks, it's possible that the free space calculation in xfs_reserve_blocks will spit out a negative number (because percpu_counter_sum returns s64). We fail to notice this negative number and set fdblks_delta to it. Now we increment fdblocks(!) and the unsigned type of m_resblks means that we end up setting a ridiculously huge m_resblks reservation. Avoid this comedy of errors by detecting the negative free space and returning -ENOSPC. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>