| Message ID | 20171009215533.12530-2-mreitz@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | qcow2: Fix preallocated truncation | expand |
On 2017-10-09 23:55, Max Reitz wrote: > A qcow2 image file's length is not required to have a length that is a > multiple of the cluster size. However, qcow2_refcount_area() expects an > aligned value for its @start_offset parameter, so we need to round > @old_file_size up to the next cluster boundary. > > Reported-by: pingl <pingl@redhat.com> > Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049 > Signed-off-by: Max Reitz <mreitz@redhat.com> > --- > block/qcow2.c | 1 + > 1 file changed, 1 insertion(+) Oops, forgot: Cc: qemu-stable@nongnu.org (2.10.1 is out by now, but you never know.)
On 10/09/2017 04:55 PM, Max Reitz wrote: > A qcow2 image file's length is not required to have a length that is a > multiple of the cluster size. However, qcow2_refcount_area() expects an > aligned value for its @start_offset parameter, so we need to round > @old_file_size up to the next cluster boundary. > > Reported-by: pingl <pingl@redhat.com> Should we use a real name? My autocomplete when adding cc suggests Ping Li. (The upcoming git 2.15.0 adds my patch that auto-cc's anyone listed in Reported-by, so we don't have to keep doing it manually: https://github.com/git/git/commit/09ac6737 - but that doesn't help you while you are still on 2.13.6) > Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049 > Signed-off-by: Max Reitz <mreitz@redhat.com> > --- > block/qcow2.c | 1 + > 1 file changed, 1 insertion(+) > Reviewed-by: Eric Blake <eblake@redhat.com>
On Mon, Oct 09, 2017 at 11:55:31PM +0200, Max Reitz wrote: > A qcow2 image file's length is not required to have a length that is a > multiple of the cluster size. However, qcow2_refcount_area() expects an > aligned value for its @start_offset parameter, so we need to round > @old_file_size up to the next cluster boundary. > > Reported-by: pingl <pingl@redhat.com> > Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049 > Signed-off-by: Max Reitz <mreitz@redhat.com> > --- > block/qcow2.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/qcow2.c b/block/qcow2.c > index 2f6a8e1ff8..c3b312cdef 100644 > --- a/block/qcow2.c > +++ b/block/qcow2.c > @@ -3193,6 +3193,7 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset, > "Failed to inquire current file length"); > return old_file_size; > } > + old_file_size = ROUND_UP(old_file_size, s->cluster_size); > > nb_new_data_clusters = DIV_ROUND_UP(offset - old_length, > s->cluster_size); > -- > 2.13.6 > > Reviewed-by: Jeff Cody <jcody@redhat.com>
On 2017-10-10 00:25, Eric Blake wrote: > On 10/09/2017 04:55 PM, Max Reitz wrote: >> A qcow2 image file's length is not required to have a length that is a >> multiple of the cluster size. However, qcow2_refcount_area() expects an >> aligned value for its @start_offset parameter, so we need to round >> @old_file_size up to the next cluster boundary. >> >> Reported-by: pingl <pingl@redhat.com> > > Should we use a real name? My autocomplete when adding cc suggests Ping Li. So does Red Hat's staff search. :-) I thought I'd just take the name from the BZ, so I'd be safe -- pleading the fact that real names are only required for S-o-bs. But well, why not. > (The upcoming git 2.15.0 adds my patch that auto-cc's anyone listed in > Reported-by, so we don't have to keep doing it manually: > https://github.com/git/git/commit/09ac6737 - but that doesn't help you > while you are still on 2.13.6) I like doing it manually because I don't like CC-ing only singular patches of a series, though -- at least not without CC-ing the cover letter, too. So far I was lucky enough not to get into a situation where I didn't want someone I wanted to CC on one patch not to see the whole series. (In this case here I don't think Red Hat QA gains much from seeing the upstream patch.) If I get unlucky in the future, I guess I'll have to extend my email sending script... >> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049 >> Signed-off-by: Max Reitz <mreitz@redhat.com> >> --- >> block/qcow2.c | 1 + >> 1 file changed, 1 insertion(+) >> > > Reviewed-by: Eric Blake <eblake@redhat.com> Thanks! Max
diff --git a/block/qcow2.c b/block/qcow2.c index 2f6a8e1ff8..c3b312cdef 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3193,6 +3193,7 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset, "Failed to inquire current file length"); return old_file_size; } + old_file_size = ROUND_UP(old_file_size, s->cluster_size); nb_new_data_clusters = DIV_ROUND_UP(offset - old_length, s->cluster_size);
A qcow2 image file's length is not required to have a length that is a multiple of the cluster size. However, qcow2_refcount_area() expects an aligned value for its @start_offset parameter, so we need to round @old_file_size up to the next cluster boundary. Reported-by: pingl <pingl@redhat.com> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049 Signed-off-by: Max Reitz <mreitz@redhat.com> --- block/qcow2.c | 1 + 1 file changed, 1 insertion(+)