On Fri, Jun 08, 2018 at 11:10:39AM +1000, Dave Chinner wrote: > On Thu, Jun 07, 2018 at 09:16:31AM -0700, Darrick J. Wong wrote: > > On Tue, Jun 05, 2018 at 10:10:15AM -0700, Darrick J. Wong wrote: > > > On Tue, Jun 05, 2018 at 04:24:19PM +1000, Dave Chinner wrote: > > > > From: Dave Chinner <dchinner@xxxxxxxxxx> > > > > > > > > There are rules for vald extent size hints. We enforce them when > > > > applications set them, but fuzzers violate those rules and that > > > > screws us over. > > > > > > > > This results in alignment assertion failures when setting up > > > > allocations such as this in direct IO: > > > > > > > > XFS: Assertion failed: ap->length, file: fs/xfs/libxfs/xfs_bmap.c, line: 3432 > > > > .... > > > > Call Trace: > > > > xfs_bmap_btalloc+0x415/0x910 > > > > xfs_bmapi_write+0x71c/0x12e0 > > > > xfs_iomap_write_direct+0x2a9/0x420 > > > > xfs_file_iomap_begin+0x4dc/0xa70 > > > > iomap_apply+0x43/0x100 > > > > iomap_file_buffered_write+0x62/0x90 > > > > xfs_file_buffered_aio_write+0xba/0x300 > > > > __vfs_write+0xd5/0x150 > > > > vfs_write+0xb6/0x180 > > > > ksys_write+0x45/0xa0 > > > > do_syscall_64+0x5a/0x180 > > > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > > > > > > > And from xfs_db: > > > > > > > > core.extsize = 10380288 > > > > > > > > Which is not an integer multiple of the block size, and so violates > > > > Rule #7 for setting extent size hints. Validate extent size hint > > > > rules in the inode verifier to catch this. > > > > > > > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> > > > > > > Looks ok modulo my comments in the next patch, > > > Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > > > FWIW when I applied this to xfsprogs I saw an xfs/033 regression: > > > > Phase 6 - check inode connectivity... > > reinitializing root directory > > Metadata corruption detected at 0x5555555c60e0, inode 0x80 dinode > > > > fatal error -- could not iget root inode -- error - 117 > > [Inferior 1 (process 1178) exited with code 01] > > (gdb) l *(0x5555555c60e0) > > 0x5555555c60e0 is in libxfs_inode_validate_extsize (xfs_inode_buf.c:729). > > > > We fail the inode verifier while trying to _iget the root inode so that > > we can reinitialize it; I suspect phase 3 is going to need to check the > > extent size hints and clear them. > > I'm actually quite happy to see that the continual process of > hardening the kernel verifiers has got to the point where we are > starting to expose deficiencies in xfs_repair. > > Can I wait for the xfsprogs libxfs-4.18-sync branch to pick up these > verifier changes before looking at what repair needs to do to avoid > it? I don't want to do a forced context switch to > debugging/enhancing userspace code right at this moment.... That's ultimately up to Eric, but since fixing it is nontrivial surgery on xfs_repair (and the verifier update patch doesn't itself break the build) I'd be fine with fixing it after the 4.18 sync goes in. --D > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx > -- > 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 -- 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
