Message ID | 20180725213336.16263-1-billodo@redhat.com (mailing list archive) |
---|---|
State | Superseded, archived |
Headers | show |
Series | [v3] libxfs: add more bounds checking to sb sanity checks | expand |
On Wed, Jul 25, 2018 at 04:33:36PM -0500, Bill O'Donnell wrote: > Current sb verifier doesn't check bounds on sb_fdblocks and sb_ifree. > Add sanity checks for these parameters. > > Signed-off-by: Bill O'Donnell <billodo@redhat.com> > --- > v3: eliminate need for additional write_flag, doing those > unique checks in xfs_sb_write_verify() > v2: make extra sanity checks exclusive to writes > > > fs/xfs/libxfs/xfs_sb.c | 38 ++++++++++++++++++++++++++++---------- > 1 file changed, 28 insertions(+), 10 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c > index b3ad15956366..f583fb8a10e1 100644 > --- a/fs/xfs/libxfs/xfs_sb.c > +++ b/fs/xfs/libxfs/xfs_sb.c > @@ -599,22 +599,16 @@ xfs_sb_to_disk( > static int > xfs_sb_verify( > struct xfs_buf *bp, > + struct xfs_sb *sb, > bool check_version) > { > struct xfs_mount *mp = bp->b_target->bt_mount; > - struct xfs_sb sb; > - > - /* > - * Use call variant which doesn't convert quota flags from disk > - * format, because xfs_mount_validate_sb checks the on-disk flags. > - */ > - __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > > /* > * Only check the in progress field for the primary superblock as > * mkfs.xfs doesn't clear it from secondary superblocks. > */ > - return xfs_mount_validate_sb(mp, &sb, > + return xfs_mount_validate_sb(mp, sb, > bp->b_maps[0].bm_bn == XFS_SB_DADDR, > check_version); > } > @@ -637,6 +631,7 @@ xfs_sb_read_verify( > { > struct xfs_mount *mp = bp->b_target->bt_mount; > struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); > + struct xfs_sb sb; > int error; > > /* > @@ -657,7 +652,13 @@ xfs_sb_read_verify( > } > } > } > - error = xfs_sb_verify(bp, true); > + > + /* > + * Use call variant which doesn't convert quota flags from disk > + * format, because xfs_mount_validate_sb checks the on-disk flags. > + */ > + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > + error = xfs_sb_verify(bp, &sb, true); > > out_error: > if (error == -EFSCORRUPTED || error == -EFSBADCRC) > @@ -693,9 +694,26 @@ xfs_sb_write_verify( > { > struct xfs_mount *mp = bp->b_target->bt_mount; > struct xfs_buf_log_item *bip = bp->b_log_item; > + struct xfs_sb sb; > int error; > > - error = xfs_sb_verify(bp, false); > + /* > + * Use call variant which doesn't convert quota flags from disk > + * format, because xfs_mount_validate_sb checks the on-disk flags. > + */ > + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > + > + error = xfs_sb_verify(bp, &sb, false); > + > + /* Additional sb sanity checks for writes */ > + if (!error) { > + if (sb.sb_fdblocks > sb.sb_dblocks || > + sb.sb_ifree > sb.sb_icount) { > + xfs_notice(mp, "SB sanity check failed"); > + error = -EFSCORRUPTED; > + } > + } On the off chance that some day we add more write-time checks, could you please structure this the usual way? error = xfs_sb_verify(bp, &sb, false); if (error) goto err; if (sb.sb_fdblocks > sb.sb_dblocks || sb.sb_ifree > sb.sb_icount) { xfs_notice(mp, "SB summary counter sanity check failed"); error = -EFSCORRUPTED; goto err; } err: if (error) { xfs_verifier_error(bp, error, __this_address); return; } } Other than that, this looks ok to me. --D > + > if (error) { > xfs_verifier_error(bp, error, __this_address); > return; > -- > 2.17.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > 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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Jul 25, 2018 at 02:47:47PM -0700, Darrick J. Wong wrote: > On Wed, Jul 25, 2018 at 04:33:36PM -0500, Bill O'Donnell wrote: > > Current sb verifier doesn't check bounds on sb_fdblocks and sb_ifree. > > Add sanity checks for these parameters. > > > > Signed-off-by: Bill O'Donnell <billodo@redhat.com> > > --- > > v3: eliminate need for additional write_flag, doing those > > unique checks in xfs_sb_write_verify() > > v2: make extra sanity checks exclusive to writes > > > > > > fs/xfs/libxfs/xfs_sb.c | 38 ++++++++++++++++++++++++++++---------- > > 1 file changed, 28 insertions(+), 10 deletions(-) > > > > diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c > > index b3ad15956366..f583fb8a10e1 100644 > > --- a/fs/xfs/libxfs/xfs_sb.c > > +++ b/fs/xfs/libxfs/xfs_sb.c > > @@ -599,22 +599,16 @@ xfs_sb_to_disk( > > static int > > xfs_sb_verify( > > struct xfs_buf *bp, > > + struct xfs_sb *sb, > > bool check_version) > > { > > struct xfs_mount *mp = bp->b_target->bt_mount; > > - struct xfs_sb sb; > > - > > - /* > > - * Use call variant which doesn't convert quota flags from disk > > - * format, because xfs_mount_validate_sb checks the on-disk flags. > > - */ > > - __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > > > > /* > > * Only check the in progress field for the primary superblock as > > * mkfs.xfs doesn't clear it from secondary superblocks. > > */ > > - return xfs_mount_validate_sb(mp, &sb, > > + return xfs_mount_validate_sb(mp, sb, > > bp->b_maps[0].bm_bn == XFS_SB_DADDR, > > check_version); > > } > > @@ -637,6 +631,7 @@ xfs_sb_read_verify( > > { > > struct xfs_mount *mp = bp->b_target->bt_mount; > > struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); > > + struct xfs_sb sb; > > int error; > > > > /* > > @@ -657,7 +652,13 @@ xfs_sb_read_verify( > > } > > } > > } > > - error = xfs_sb_verify(bp, true); > > + > > + /* > > + * Use call variant which doesn't convert quota flags from disk > > + * format, because xfs_mount_validate_sb checks the on-disk flags. > > + */ > > + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > > + error = xfs_sb_verify(bp, &sb, true); > > > > out_error: > > if (error == -EFSCORRUPTED || error == -EFSBADCRC) > > @@ -693,9 +694,26 @@ xfs_sb_write_verify( > > { > > struct xfs_mount *mp = bp->b_target->bt_mount; > > struct xfs_buf_log_item *bip = bp->b_log_item; > > + struct xfs_sb sb; > > int error; > > > > - error = xfs_sb_verify(bp, false); > > + /* > > + * Use call variant which doesn't convert quota flags from disk > > + * format, because xfs_mount_validate_sb checks the on-disk flags. > > + */ > > + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); > > + > > + error = xfs_sb_verify(bp, &sb, false); > > + > > + /* Additional sb sanity checks for writes */ > > + if (!error) { > > + if (sb.sb_fdblocks > sb.sb_dblocks || > > + sb.sb_ifree > sb.sb_icount) { > > + xfs_notice(mp, "SB sanity check failed"); > > + error = -EFSCORRUPTED; > > + } > > + } > > On the off chance that some day we add more write-time checks, could you > please structure this the usual way? ah, good idea... will do! Thanks- Bill > > error = xfs_sb_verify(bp, &sb, false); > if (error) > goto err; > > if (sb.sb_fdblocks > sb.sb_dblocks || sb.sb_ifree > sb.sb_icount) { > xfs_notice(mp, "SB summary counter sanity check failed"); > error = -EFSCORRUPTED; > goto err; > } > > err: > if (error) { > xfs_verifier_error(bp, error, __this_address); > return; > } > } > > Other than that, this looks ok to me. > > --D > > > + > > if (error) { > > xfs_verifier_error(bp, error, __this_address); > > return; > > -- > > 2.17.1 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > > the body of a message to majordomo@vger.kernel.org > > 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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 7/25/18 2:33 PM, Bill O'Donnell wrote: > + /* Additional sb sanity checks for writes */ > + if (!error) { > + if (sb.sb_fdblocks > sb.sb_dblocks || > + sb.sb_ifree > sb.sb_icount) { > + xfs_notice(mp, "SB sanity check failed"); > + error = -EFSCORRUPTED; > + } > + } I had kind of had it in my head that Dave suggested testing not only sb_fdblocks & sb_ifree but also validating sb_icount against sb_dblocks ... would that make sense? something like: + if (sb.sb_fdblocks > sb.sb_dblocks || + sb.sb_icount / sb.sb_inopblock > sb.sb_dblocks) || + sb.sb_ifree > sb.sb_icount) { + xfs_notice(mp, "SB sanity check failed"); because all 3 go into the statfs calculations which went wonky in the original report? (xfs_sb_verify has done some sanity checks on sb_inopblock by the time we get here.) Also, a comment about why these checks are only for write, and are not simply in xfs_mount_validate_sb() would be good, since that obviously wasn't obvious to me at first. o_O :) -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Jul 25, 2018 at 03:48:51PM -0700, Eric Sandeen wrote: > > > On 7/25/18 2:33 PM, Bill O'Donnell wrote: > > + /* Additional sb sanity checks for writes */ > > + if (!error) { > > + if (sb.sb_fdblocks > sb.sb_dblocks || > > + sb.sb_ifree > sb.sb_icount) { > > + xfs_notice(mp, "SB sanity check failed"); > > + error = -EFSCORRUPTED; > > + } > > + } > > I had kind of had it in my head that Dave suggested testing not > only sb_fdblocks & sb_ifree but also validating sb_icount against > sb_dblocks ... would that make sense? something like: > > + if (sb.sb_fdblocks > sb.sb_dblocks || > + sb.sb_icount / sb.sb_inopblock > sb.sb_dblocks) || That would make sense, but perhaps we should have a xfs_verify_icount instead of open-coding a 64-bit division? :) Granted, I /was/ planning to add all that as part of fs summary counter scrubbing next cycle. --D > + sb.sb_ifree > sb.sb_icount) { > + xfs_notice(mp, "SB sanity check failed"); > > because all 3 go into the statfs calculations which went wonky > in the original report? (xfs_sb_verify has done some sanity > checks on sb_inopblock by the time we get here.) > > Also, a comment about why these checks are only for write, and are not > simply in xfs_mount_validate_sb() would be good, since that obviously > wasn't obvious to me at first. o_O :) > > -Eric > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > 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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index b3ad15956366..f583fb8a10e1 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -599,22 +599,16 @@ xfs_sb_to_disk( static int xfs_sb_verify( struct xfs_buf *bp, + struct xfs_sb *sb, bool check_version) { struct xfs_mount *mp = bp->b_target->bt_mount; - struct xfs_sb sb; - - /* - * Use call variant which doesn't convert quota flags from disk - * format, because xfs_mount_validate_sb checks the on-disk flags. - */ - __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); /* * Only check the in progress field for the primary superblock as * mkfs.xfs doesn't clear it from secondary superblocks. */ - return xfs_mount_validate_sb(mp, &sb, + return xfs_mount_validate_sb(mp, sb, bp->b_maps[0].bm_bn == XFS_SB_DADDR, check_version); } @@ -637,6 +631,7 @@ xfs_sb_read_verify( { struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); + struct xfs_sb sb; int error; /* @@ -657,7 +652,13 @@ xfs_sb_read_verify( } } } - error = xfs_sb_verify(bp, true); + + /* + * Use call variant which doesn't convert quota flags from disk + * format, because xfs_mount_validate_sb checks the on-disk flags. + */ + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); + error = xfs_sb_verify(bp, &sb, true); out_error: if (error == -EFSCORRUPTED || error == -EFSBADCRC) @@ -693,9 +694,26 @@ xfs_sb_write_verify( { struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_buf_log_item *bip = bp->b_log_item; + struct xfs_sb sb; int error; - error = xfs_sb_verify(bp, false); + /* + * Use call variant which doesn't convert quota flags from disk + * format, because xfs_mount_validate_sb checks the on-disk flags. + */ + __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); + + error = xfs_sb_verify(bp, &sb, false); + + /* Additional sb sanity checks for writes */ + if (!error) { + if (sb.sb_fdblocks > sb.sb_dblocks || + sb.sb_ifree > sb.sb_icount) { + xfs_notice(mp, "SB sanity check failed"); + error = -EFSCORRUPTED; + } + } + if (error) { xfs_verifier_error(bp, error, __this_address); return;
Current sb verifier doesn't check bounds on sb_fdblocks and sb_ifree. Add sanity checks for these parameters. Signed-off-by: Bill O'Donnell <billodo@redhat.com> --- v3: eliminate need for additional write_flag, doing those unique checks in xfs_sb_write_verify() v2: make extra sanity checks exclusive to writes fs/xfs/libxfs/xfs_sb.c | 38 ++++++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 10 deletions(-)