| Message ID | 8b53a29b3ec90c9a7030e8fa3e1555ad5802dce9.1469680625.git.calvinowens@fb.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
>>>>> "Calvin" == Calvin Owens <calvinowens@fb.com> writes:
Calvin> We blindly trust the hardware to give us NUL-terminated strings,
Calvin> which is a bad idea because it doesn't always do that. For
Calvin> example:
Broadcom folks, please respond to this and other mpt3sas patches in the
queue:
https://patchwork.kernel.org/project/linux-scsi/list/?q=mpt3sas
>>>>> "Calvin" == Calvin Owens <calvinowens@fb.com> writes:
Calvin> We blindly trust the hardware to give us NUL-terminated strings,
Calvin> which is a bad idea because it doesn't always do that. For
Calvin> example:
Calvin> [ 481.184784] mpt3sas_cm0: enclosure level(0x0000), connector
Calvin> name( \x3)
Calvin> In this case, connector_name is four spaces. We got lucky here
Calvin> because the 2nd byte beyond our character array happens to be a
Calvin> NUL. Fix this by explicitly writing '\0' to the end of the
Calvin> string to ensure we don't run off the edge of the world in
Calvin> printk().
Applied to 4.9/scsi-queue.
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h index 892c9be..eb7f5b0 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.h +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h @@ -478,7 +478,7 @@ struct _sas_device { u8 pfa_led_on; u8 pend_sas_rphy_add; u8 enclosure_level; - u8 connector_name[4]; + u8 connector_name[5]; struct kref refcount; }; diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c index cd91a68..acabe48 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c @@ -5380,8 +5380,9 @@ _scsih_check_device(struct MPT3SAS_ADAPTER *ioc, MPI2_SAS_DEVICE0_FLAGS_ENCL_LEVEL_VALID) { sas_device->enclosure_level = le16_to_cpu(sas_device_pg0.EnclosureLevel); - memcpy(&sas_device->connector_name[0], - &sas_device_pg0.ConnectorName[0], 4); + memcpy(sas_device->connector_name, + sas_device_pg0.ConnectorName, 4); + sas_device->connector_name[4] = '\0'; } else { sas_device->enclosure_level = 0; sas_device->connector_name[0] = '\0'; @@ -5508,8 +5509,9 @@ _scsih_add_device(struct MPT3SAS_ADAPTER *ioc, u16 handle, u8 phy_num, if (sas_device_pg0.Flags & MPI2_SAS_DEVICE0_FLAGS_ENCL_LEVEL_VALID) { sas_device->enclosure_level = le16_to_cpu(sas_device_pg0.EnclosureLevel); - memcpy(&sas_device->connector_name[0], - &sas_device_pg0.ConnectorName[0], 4); + memcpy(sas_device->connector_name, + sas_device_pg0.ConnectorName, 4); + sas_device->connector_name[4] = '\0'; } else { sas_device->enclosure_level = 0; sas_device->connector_name[0] = '\0';
We blindly trust the hardware to give us NUL-terminated strings, which is a bad idea because it doesn't always do that. For example: [ 481.184784] mpt3sas_cm0: enclosure level(0x0000), connector name( \x3) In this case, connector_name is four spaces. We got lucky here because the 2nd byte beyond our character array happens to be a NUL. Fix this by explicitly writing '\0' to the end of the string to ensure we don't run off the edge of the world in printk(). Signed-off-by: Calvin Owens <calvinowens@fb.com> --- drivers/scsi/mpt3sas/mpt3sas_base.h | 2 +- drivers/scsi/mpt3sas/mpt3sas_scsih.c | 10 ++++++---- 2 files changed, 7 insertions(+), 5 deletions(-)