On Fri, 2019-02-01 at 21:50 +0100, David Kozub wrote: > From: Jonas Rabenstein > > Allow modification of the shadow mbr. If the shadow mbr is not marked as > done, this data will be presented read only as the device content. Only > after marking the shadow mbr as done and unlocking a locking range the > actual content is accessible. > > Co-authored-by: David Kozub > Signed-off-by: Jonas Rabenstein > Signed-off-by: David Kozub > Reviewed-by: Scott Bauer > --- > block/sed-opal.c | 89 ++++++++++++++++++++++++++++++++++- > include/linux/sed-opal.h | 1 + > include/uapi/linux/sed-opal.h | 8 ++++ > 3 files changed, 97 insertions(+), 1 deletion(-) > > diff --git a/block/sed-opal.c b/block/sed-opal.c > index e03838cfd31b..88c84906ce98 100644 > --- a/block/sed-opal.c > +++ b/block/sed-opal.c > @@ -34,6 +34,9 @@ > #define IO_BUFFER_LENGTH 2048 > #define MAX_TOKS 64 > > +/* Number of bytes needed by cmd_finalize. */ > +#define CMD_FINALIZE_BYTES_NEEDED 7 > + > struct opal_step { > int (*fn)(struct opal_dev *dev, void *data); > void *data; > @@ -668,7 +671,11 @@ static int cmd_finalize(struct opal_dev *cmd, u32 hsn, u32 tsn) > struct opal_header *hdr; > int err = 0; > > - /* close the parameter list opened from cmd_start */ > + /* > + * Close the parameter list opened from cmd_start. > + * The number of bytes added must be equal to > + * CMD_FINALIZE_BYTES_NEEDED. > + */ > add_token_u8(&err, cmd, OPAL_ENDLIST); > > add_token_u8(&err, cmd, OPAL_ENDOFDATA); > @@ -1500,6 +1507,58 @@ static int set_mbr_enable_disable(struct opal_dev *dev, void *data) > return finalize_and_send(dev, parse_and_check_status); > } > > +static int write_shadow_mbr(struct opal_dev *dev, void *data) > +{ > + struct opal_shadow_mbr *shadow = data; > + const u8 __user *src; > + u8 *dst; > + size_t off = 0; > + u64 len; > + int err = 0; > + > + /* do the actual transmission(s) */ > + src = (u8 *) shadow->data; > + while (off < shadow->size) { > + err = cmd_start(dev, opaluid[OPAL_MBR], opalmethod[OPAL_SET]); > + add_token_u8(&err, dev, OPAL_STARTNAME); > + add_token_u8(&err, dev, OPAL_WHERE); > + add_token_u64(&err, dev, shadow->offset + off); > + add_token_u8(&err, dev, OPAL_ENDNAME); > + > + add_token_u8(&err, dev, OPAL_STARTNAME); > + add_token_u8(&err, dev, OPAL_VALUES); > + > + /* > + * The bytestring header is either 1 or 2 bytes, so assume 2. > + * There also needs to be enough space to accommodate the > + * trailing OPAL_ENDNAME (1 byte) and tokens added by > + * cmd_finalize. > + */ > + len = min(remaining_size(dev) - (2+1+CMD_FINALIZE_BYTES_NEEDED), > + (size_t)(shadow->size - off)); > + pr_debug("MBR: write bytes %zu+%llu/%llu\n", > + off, len, shadow->size); > + > + dst = add_bytestring_header(&err, dev, len); > + if (!dst) > + break; > + if (copy_from_user(dst, src + off, len)) > + err = -EFAULT; > + dev->pos += len; > + > + add_token_u8(&err, dev, OPAL_ENDNAME); > + if (err) > + break; > + > + err = finalize_and_send(dev, parse_and_check_status); > + if (err) > + break; > + > + off += len; > + } > + return err; > +} > + > static int generic_pw_cmd(u8 *key, size_t key_len, u8 *cpin_uid, > struct opal_dev *dev) > { > @@ -2045,6 +2104,31 @@ static int opal_mbr_status(struct opal_dev *dev, struct opal_mbr_data *opal_mbr) > return ret; > } > > +static int opal_write_shadow_mbr(struct opal_dev *dev, > + struct opal_shadow_mbr *info) > +{ > + const struct opal_step mbr_steps[] = { > + { opal_discovery0, }, > + { start_admin1LSP_opal_session, &info->key }, > + { write_shadow_mbr, info }, > + { end_opal_session, }, > + { NULL, } > + }; > + int ret; > + > + if (info->size == 0) > + return 0; > + > + if (!access_ok(info->data, info->size)) > + return -EINVAL; -EFAULT? > + > + mutex_lock(&dev->dev_lock); > + setup_opal_dev(dev, mbr_steps); > + ret = next(dev); > + mutex_unlock(&dev->dev_lock); > + return ret; > +} > + > static int opal_save(struct opal_dev *dev, struct opal_lock_unlock *lk_unlk) > { > struct opal_suspend_data *suspend; > @@ -2378,6 +2462,9 @@ int sed_ioctl(struct opal_dev *dev, unsigned int cmd, void __user *arg) > case IOC_OPAL_MBR_STATUS: > ret = opal_mbr_status(dev, p); > break; > + case IOC_OPAL_WRITE_SHADOW_MBR: > + ret = opal_write_shadow_mbr(dev, p); > + break; > case IOC_OPAL_ERASE_LR: > ret = opal_erase_locking_range(dev, p); > break; > diff --git a/include/linux/sed-opal.h b/include/linux/sed-opal.h > index b38dc602cae3..cf08cdc13cbd 100644 > --- a/include/linux/sed-opal.h > +++ b/include/linux/sed-opal.h > @@ -47,6 +47,7 @@ static inline bool is_sed_ioctl(unsigned int cmd) > case IOC_OPAL_ENABLE_DISABLE_MBR: > case IOC_OPAL_ERASE_LR: > case IOC_OPAL_SECURE_ERASE_LR: > + case IOC_OPAL_WRITE_SHADOW_MBR: > case IOC_OPAL_MBR_STATUS: > return true; > } > diff --git a/include/uapi/linux/sed-opal.h b/include/uapi/linux/sed-opal.h > index 0cb9890cdc04..8e84307f66d4 100644 > --- a/include/uapi/linux/sed-opal.h > +++ b/include/uapi/linux/sed-opal.h > @@ -104,6 +104,13 @@ struct opal_mbr_data { > __u8 __align[7]; > }; > > +struct opal_shadow_mbr { > + struct opal_key key; > + const __u64 data; > + __u64 offset; > + __u64 size; > +}; > + > #define IOC_OPAL_SAVE _IOW('p', 220, struct opal_lock_unlock) > #define IOC_OPAL_LOCK_UNLOCK _IOW('p', 221, struct opal_lock_unlock) > #define IOC_OPAL_TAKE_OWNERSHIP _IOW('p', 222, struct opal_key) > @@ -117,5 +124,6 @@ struct opal_mbr_data { > #define IOC_OPAL_ERASE_LR _IOW('p', 230, struct opal_session_info) > #define IOC_OPAL_SECURE_ERASE_LR _IOW('p', 231, struct opal_session_info) > #define IOC_OPAL_MBR_STATUS _IOW('p', 232, struct opal_mbr_data) > +#define IOC_OPAL_WRITE_SHADOW_MBR _IOW('p', 233, struct opal_shadow_mbr) > > #endif /* _UAPI_SED_OPAL_H */ Otherwise looks good Reviewed-by: Jon Derrick