| Message ID | 780d0c59f2993cec4a0931df93b9fe12cb5d0f46.1456931418.git.jcody@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02.03.2016 16:16, Jeff Cody wrote: > The function qemu_strtoul() reads 'unsigned long' sized data, > which is larger than uint32_t on 64-bit machines. > > Even though the snap_id field in the header is 32-bits, we must > accomodate the full size in qemu_strtoul(). > > Reported-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Jeff Cody <jcody@redhat.com> > --- > block/sheepdog.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/block/sheepdog.c b/block/sheepdog.c > index 8739acc..c6bf900 100644 > --- a/block/sheepdog.c > +++ b/block/sheepdog.c > @@ -2543,7 +2543,7 @@ static int sd_snapshot_delete(BlockDriverState *bs, > const char *name, > Error **errp) > { > - uint32_t snap_id = 0; > + unsigned long snap_id = 0; > char snap_tag[SD_MAX_VDI_TAG_LEN]; > Error *local_err = NULL; > int fd, ret; > @@ -2565,12 +2565,12 @@ static int sd_snapshot_delete(BlockDriverState *bs, > memset(buf, 0, sizeof(buf)); > memset(snap_tag, 0, sizeof(snap_tag)); > pstrcpy(buf, SD_MAX_VDI_LEN, s->name); > - if (qemu_strtoul(snapshot_id, NULL, 10, (unsigned long *)&snap_id)) { > + if (qemu_strtoul(snapshot_id, NULL, 10, &snap_id)) { > return -1; > } > > if (snap_id) { > - hdr.snapid = snap_id; > + hdr.snapid = (uint32_t) snap_id; Maybe we should do an overflow check before? Max > } else { > pstrcpy(snap_tag, sizeof(snap_tag), snapshot_id); > pstrcpy(buf + SD_MAX_VDI_LEN, SD_MAX_VDI_TAG_LEN, snap_tag); >
On Wed, Mar 02, 2016 at 04:27:31PM +0100, Max Reitz wrote: > On 02.03.2016 16:16, Jeff Cody wrote: > > The function qemu_strtoul() reads 'unsigned long' sized data, > > which is larger than uint32_t on 64-bit machines. > > > > Even though the snap_id field in the header is 32-bits, we must > > accomodate the full size in qemu_strtoul(). > > > > Reported-by: Paolo Bonzini <pbonzini@redhat.com> > > Signed-off-by: Jeff Cody <jcody@redhat.com> > > --- > > block/sheepdog.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/block/sheepdog.c b/block/sheepdog.c > > index 8739acc..c6bf900 100644 > > --- a/block/sheepdog.c > > +++ b/block/sheepdog.c > > @@ -2543,7 +2543,7 @@ static int sd_snapshot_delete(BlockDriverState *bs, > > const char *name, > > Error **errp) > > { > > - uint32_t snap_id = 0; > > + unsigned long snap_id = 0; > > char snap_tag[SD_MAX_VDI_TAG_LEN]; > > Error *local_err = NULL; > > int fd, ret; > > @@ -2565,12 +2565,12 @@ static int sd_snapshot_delete(BlockDriverState *bs, > > memset(buf, 0, sizeof(buf)); > > memset(snap_tag, 0, sizeof(snap_tag)); > > pstrcpy(buf, SD_MAX_VDI_LEN, s->name); > > - if (qemu_strtoul(snapshot_id, NULL, 10, (unsigned long *)&snap_id)) { > > + if (qemu_strtoul(snapshot_id, NULL, 10, &snap_id)) { > > return -1; > > } > > > > if (snap_id) { > > - hdr.snapid = snap_id; > > + hdr.snapid = (uint32_t) snap_id; > > Maybe we should do an overflow check before? > Probably not a bad idea - easy enough, and that would prevent a false positive match due to id truncation. I'll spin a v2. Jeff
diff --git a/block/sheepdog.c b/block/sheepdog.c index 8739acc..c6bf900 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -2543,7 +2543,7 @@ static int sd_snapshot_delete(BlockDriverState *bs, const char *name, Error **errp) { - uint32_t snap_id = 0; + unsigned long snap_id = 0; char snap_tag[SD_MAX_VDI_TAG_LEN]; Error *local_err = NULL; int fd, ret; @@ -2565,12 +2565,12 @@ static int sd_snapshot_delete(BlockDriverState *bs, memset(buf, 0, sizeof(buf)); memset(snap_tag, 0, sizeof(snap_tag)); pstrcpy(buf, SD_MAX_VDI_LEN, s->name); - if (qemu_strtoul(snapshot_id, NULL, 10, (unsigned long *)&snap_id)) { + if (qemu_strtoul(snapshot_id, NULL, 10, &snap_id)) { return -1; } if (snap_id) { - hdr.snapid = snap_id; + hdr.snapid = (uint32_t) snap_id; } else { pstrcpy(snap_tag, sizeof(snap_tag), snapshot_id); pstrcpy(buf + SD_MAX_VDI_LEN, SD_MAX_VDI_TAG_LEN, snap_tag);
The function qemu_strtoul() reads 'unsigned long' sized data, which is larger than uint32_t on 64-bit machines. Even though the snap_id field in the header is 32-bits, we must accomodate the full size in qemu_strtoul(). Reported-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com> --- block/sheepdog.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)