[PATCH] ima: Fix the error code for restoring the PCR value

[PATCH] ima: Fix the error code for restoring the PCR value

[Li Huafei]

In ima_restore_measurement_list(), hdr[HDR_PCR].data is pointing to a
buffer of type u8, which contains the dumped 32-bit pcr value.
Currently, only the least significant byte is used to restore the pcr
value. We should convert hdr[HDR_PCR].data to a pointer of type u32
before fetching the value to restore the correct pcr value.

Fixes: 47fdee60b47f ("ima: use ima_parse_buf() to parse measurements headers")
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
---
 security/integrity/ima/ima_template.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index e22e510ae92d..4e081e650047 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -494,8 +494,8 @@ int ima_restore_measurement_list(loff_t size, void *buf)
 			}
 		}
 
-		entry->pcr = !ima_canonical_fmt ? *(hdr[HDR_PCR].data) :
-			     le32_to_cpu(*(hdr[HDR_PCR].data));
+		entry->pcr = !ima_canonical_fmt ? *(u32 *)(hdr[HDR_PCR].data) :
+			     le32_to_cpu(*(u32 *)(hdr[HDR_PCR].data));
 		ret = ima_restore_measurement_entry(entry);
 		if (ret < 0)
 			break;
-- 
2.17.1

Re: [PATCH] ima: Fix the error code for restoring the PCR value

[Li Huafei]

ping. :-)

On 2021/3/3 11:28, Li Huafei wrote:
> In ima_restore_measurement_list(), hdr[HDR_PCR].data is pointing to a
> buffer of type u8, which contains the dumped 32-bit pcr value.
> Currently, only the least significant byte is used to restore the pcr
> value. We should convert hdr[HDR_PCR].data to a pointer of type u32
> before fetching the value to restore the correct pcr value.
> 
> Fixes: 47fdee60b47f ("ima: use ima_parse_buf() to parse measurements headers")
> Signed-off-by: Li Huafei <lihuafei1@huawei.com>
> ---
>   security/integrity/ima/ima_template.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
> index e22e510ae92d..4e081e650047 100644
> --- a/security/integrity/ima/ima_template.c
> +++ b/security/integrity/ima/ima_template.c
> @@ -494,8 +494,8 @@ int ima_restore_measurement_list(loff_t size, void *buf)
>   			}
>   		}
>   
> -		entry->pcr = !ima_canonical_fmt ? *(hdr[HDR_PCR].data) :
> -			     le32_to_cpu(*(hdr[HDR_PCR].data));
> +		entry->pcr = !ima_canonical_fmt ? *(u32 *)(hdr[HDR_PCR].data) :
> +			     le32_to_cpu(*(u32 *)(hdr[HDR_PCR].data));
>   		ret = ima_restore_measurement_entry(entry);
>   		if (ret < 0)
>   			break;
> 

RE: [PATCH] ima: Fix the error code for restoring the PCR value

[Roberto Sassu]

> From: lihuafei
> Sent: Tuesday, March 23, 2021 2:41 PM
> ping. :-)
> 
> On 2021/3/3 11:28, Li Huafei wrote:
> > In ima_restore_measurement_list(), hdr[HDR_PCR].data is pointing to a
> > buffer of type u8, which contains the dumped 32-bit pcr value.
> > Currently, only the least significant byte is used to restore the pcr
> > value. We should convert hdr[HDR_PCR].data to a pointer of type u32
> > before fetching the value to restore the correct pcr value.
> >
> > Fixes: 47fdee60b47f ("ima: use ima_parse_buf() to parse measurements
> headers")
> > Signed-off-by: Li Huafei <lihuafei1@huawei.com>

Hi Li Huafei

yes, correct. Thanks for the patch.

Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>

Roberto

HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063
Managing Director: Li Peng, Li Jian, Shi Yanli

> > ---
> >   security/integrity/ima/ima_template.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/security/integrity/ima/ima_template.c
> b/security/integrity/ima/ima_template.c
> > index e22e510ae92d..4e081e650047 100644
> > --- a/security/integrity/ima/ima_template.c
> > +++ b/security/integrity/ima/ima_template.c
> > @@ -494,8 +494,8 @@ int ima_restore_measurement_list(loff_t size, void
> *buf)
> >   			}
> >   		}
> >
> > -		entry->pcr = !ima_canonical_fmt ? *(hdr[HDR_PCR].data) :
> > -			     le32_to_cpu(*(hdr[HDR_PCR].data));
> > +		entry->pcr = !ima_canonical_fmt ? *(u32
> *)(hdr[HDR_PCR].data) :
> > +			     le32_to_cpu(*(u32 *)(hdr[HDR_PCR].data));
> >   		ret = ima_restore_measurement_entry(entry);
> >   		if (ret < 0)
> >   			break;
> >

Re: [PATCH] ima: Fix the error code for restoring the PCR value

[Mimi Zohar]

On Wed, 2021-03-24 at 09:00 +0000, Roberto Sassu wrote:
> > From: lihuafei
> > Sent: Tuesday, March 23, 2021 2:41 PM
> > ping. :-)
> > 
> > On 2021/3/3 11:28, Li Huafei wrote:
> > > In ima_restore_measurement_list(), hdr[HDR_PCR].data is pointing to a
> > > buffer of type u8, which contains the dumped 32-bit pcr value.
> > > Currently, only the least significant byte is used to restore the pcr
> > > value. We should convert hdr[HDR_PCR].data to a pointer of type u32
> > > before fetching the value to restore the correct pcr value.
> > >
> > > Fixes: 47fdee60b47f ("ima: use ima_parse_buf() to parse measurements
> > headers")
> > > Signed-off-by: Li Huafei <lihuafei1@huawei.com>
> 
> Hi Li Huafei
> 
> yes, correct. Thanks for the patch.
> 
> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>

The patch set is now queued in next-integrity-testing.

thanks,

Mimi