On Thu, Jun 21, 2018 at 11:31:22AM -0700, Darrick J. Wong wrote: > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > 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@xxxxxxxxxx> Looks good, Reviewed-by: Christoph Hellwig <hch@xxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
