| Message ID | 72e19ec70ffac23fff658c60eaae0db850150ca1.1521482296.git.jonas.rabenstein@studium.uni-erlangen.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Mar 19, 2018 at 07:36:53PM +0100, Jonas Rabenstein wrote: > Check whether the shadow mbr does fit in the provided space on the > target. Also a proper firmware should handle this case and return an > error we may prevent problems or even damage with crappy firmwares. > > Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de> > > diff --git a/block/sed-opal.c b/block/sed-opal.c > index 51f8034edbf7..9c73bd24c55f 100644 > --- a/block/sed-opal.c > +++ b/block/sed-opal.c > @@ -1545,6 +1545,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) > u64 len; > int err = 0; > > + /* do we fit in the available shadow mbr space? */ > + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); And here it gets used. So this should be merged with the previous patch.
On Mon, Mar 19, 2018 at 09:01:51PM +0100, Christoph Hellwig wrote: > On Mon, Mar 19, 2018 at 07:36:53PM +0100, Jonas Rabenstein wrote: > > Check whether the shadow mbr does fit in the provided space on the > > target. Also a proper firmware should handle this case and return an > > error we may prevent problems or even damage with crappy firmwares. > > > > Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de> > > > > diff --git a/block/sed-opal.c b/block/sed-opal.c > > index 51f8034edbf7..9c73bd24c55f 100644 > > --- a/block/sed-opal.c > > +++ b/block/sed-opal.c > > @@ -1545,6 +1545,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) > > u64 len; > > int err = 0; > > > > + /* do we fit in the available shadow mbr space? */ > > + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); > > And here it gets used. So this should be merged with the previous patch. Thought, as the previous one provides a generic interface which is only used here for this specific use case, separate patches would be better. But I will merge them in a v3 with all the other comments on the other patches.
diff --git a/block/sed-opal.c b/block/sed-opal.c index 51f8034edbf7..9c73bd24c55f 100644 --- a/block/sed-opal.c +++ b/block/sed-opal.c @@ -1545,6 +1545,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) u64 len; int err = 0; + /* do we fit in the available shadow mbr space? */ + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); + if (err) { + pr_debug("MBR: could not get shadow size\n"); + return err; + } + + len = response_get_u64(&dev->parsed, 4); + if (shadow->offset + shadow->size > len) { + pr_debug("MBR: does not fit in shadow (%llu vs. %llu)\n", + shadow->offset + shadow->size, len); + return -ENOSPC; + } + /* FIXME: this is the maximum we can use for IO_BUFFER_LENGTH=2048. * Instead of having a constant value, it would be nice to * compute the actual value depending on IO_BUFFER_LENGTH
Check whether the shadow mbr does fit in the provided space on the target. Also a proper firmware should handle this case and return an error we may prevent problems or even damage with crappy firmwares. Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>