Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Wed, Feb 27, 2019 at 12:04:49PM -0300, Murilo Opsfelder Araujo wrote: > Hi, David. > > On Wed, Feb 27, 2019 at 10:19:20AM +1100, David Gibson wrote: > > On Tue, Feb 26, 2019 at 04:11:40PM -0300, Murilo Opsfelder Araujo wrote: > > > On Tue, Feb 26, 2019 at 02:08:30PM -0300, Murilo Opsfelder Araujo wrote: > > > > Hi, Maxiwell. > > > > > > > > On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > > > > > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > > > > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo > > > > > > wrote: > > > > > > > Hi, Maxiwell. > > > > > > > > > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia > > > > > > > wrote: > > > > > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > > > > > guest to collect host information. It is disabled by default to > > > > > > > > avoid unwanted information leakage. To enable it, use: > > > > > > > > ‘-M pseries,vpd-export=on’ > > > > > > > > > > > > > > The patch for setting host-serial and host-model already landed > > > > > > > Gibson's > > > > > > > ppc-for-4.0 branch: > > > > > > > > > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > > > > > Author: Prasad J Pandit > > > > > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > > > > > > > > > ppc: add host-serial and host-model machine attributes > > > > > > > (CVE-2019-8934) > > > > > > > > > > > > > > > > > > > > > QEMU should only return host-serial and host-model from the host > > > > > > > if the > > > > > > > following combination of parameters are provided: > > > > > > > > > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > > > > > > > > > If host-serial or host-model are set with a user-string, > > > > > > > ibm,get-vpd should > > > > > > > honor these values and return them, not exposing host information > > > > > > > by accident. > > > > > > > > > > > > > > I'm not even sure if we need vpd-export= setting. Its logic > > > > > > > could be > > > > > > > derived from the presence of host-serial=passthrough and > > > > > > > host-model=passthrough > > > > > > > options. > > > > > > > > > > > > > > What do you think? > > > > > > > > > > > > That's an excellent point - I hadn't thought through the fact that > > > > > > this is the same information exposed by those properties. I do > > > > > > indeed > > > > > > think that exposing the same information set in those properties - > > > > > > and > > > > > > thereby avoiding the new machine option - would be a better plan. > > > > > > > > > > > > > > > > I saw that the patch was applied. So I will work in another patch > > > > > to use these properties and remove the export-vpd option. > > > > > > > > > > Another thing that I thought the fact that 'host-serial' and > > > > > 'host-model' > > > > > nodes in Device Tree are not in accordance with LoPAPR document. What > > > > > you think in use only get-vpd to get these information and remove > > > > > nodes from device tree? > > > > > > > > Both "system-id" and "model" properties are described in the section > > > > "3.3.2.1 > > > > Root Node Properties" of the "Device Tree Bindings: Linux on Power > > > > Architecture > > > > Reference" document: > > > > > > > > https://members.openpowerfoundation.org/wg/SYSSW/document/1455 > > > > > > I replied too early. As Maxiwell explained to me (thanks Max!), guest can > > > end up > > > having the following entries under /proc/device-tree/ (among other > > > entries): > > > > > > $ cat host-serial > > > 12A3B4C > > > > > > $ cat host-model > > > 1234-56A > > > > > > $ cat system-id > > > c7b62da9-3d0c-44f9-8edb-2318271f3c1a > > > > > > $ cat model > > > IBM pSeries (emulated by qemu) > > > > > > Where: > > > > > > - host-serial/host-model: depend on "-M host-serial" and "-M host-model" > > > machine options. > > > > > > - system-id: created when "-uuid " exists in qemu command line > > > options. > > > > > > - model: hard-coded. > > > > > > With this patch, RTAS ibm,get-vpd call will return "system-id" and > > > "model" from > > > the host, not from the guest. I found this confusing. > > > > Hrm. I found the bit in LoPAPR describing how ibm,get-vpd operates, > > but not something describing the actual data that appears within it. > > Where's that described? It'd be nice to check if those values are > > supposed to be describing the host or the guest. > > Are you asking about the fields of the ibm,vpd property? They are described in > Table 11.2 "LoPAPR VPD Fields" of this LoPAPR document: > > https://members.openpowerfoundation.org/wg/SYSSW/document/1461 That document appears to be only available to openpower members, which I'm not. I found Table 160 in my copy of LoPAPR (1.1) though, which looks like it has the same stuff. I wonder if I should be trying to get a more recent LoPAPR. -- David Gibson| I'll have
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
Hi, David. On Wed, Feb 27, 2019 at 10:19:20AM +1100, David Gibson wrote: > On Tue, Feb 26, 2019 at 04:11:40PM -0300, Murilo Opsfelder Araujo wrote: > > On Tue, Feb 26, 2019 at 02:08:30PM -0300, Murilo Opsfelder Araujo wrote: > > > Hi, Maxiwell. > > > > > > On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > > > > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > > > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo > > > > > wrote: > > > > > > Hi, Maxiwell. > > > > > > > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > > > > guest to collect host information. It is disabled by default to > > > > > > > avoid unwanted information leakage. To enable it, use: > > > > > > > ‘-M pseries,vpd-export=on’ > > > > > > > > > > > > The patch for setting host-serial and host-model already landed > > > > > > Gibson's > > > > > > ppc-for-4.0 branch: > > > > > > > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > > > > Author: Prasad J Pandit > > > > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > > > > > > > ppc: add host-serial and host-model machine attributes > > > > > > (CVE-2019-8934) > > > > > > > > > > > > > > > > > > QEMU should only return host-serial and host-model from the host if > > > > > > the > > > > > > following combination of parameters are provided: > > > > > > > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > > > > > > > If host-serial or host-model are set with a user-string, > > > > > > ibm,get-vpd should > > > > > > honor these values and return them, not exposing host information > > > > > > by accident. > > > > > > > > > > > > I'm not even sure if we need vpd-export= setting. Its logic > > > > > > could be > > > > > > derived from the presence of host-serial=passthrough and > > > > > > host-model=passthrough > > > > > > options. > > > > > > > > > > > > What do you think? > > > > > > > > > > That's an excellent point - I hadn't thought through the fact that > > > > > this is the same information exposed by those properties. I do indeed > > > > > think that exposing the same information set in those properties - and > > > > > thereby avoiding the new machine option - would be a better plan. > > > > > > > > > > > > > I saw that the patch was applied. So I will work in another patch > > > > to use these properties and remove the export-vpd option. > > > > > > > > Another thing that I thought the fact that 'host-serial' and > > > > 'host-model' > > > > nodes in Device Tree are not in accordance with LoPAPR document. What > > > > you think in use only get-vpd to get these information and remove > > > > nodes from device tree? > > > > > > Both "system-id" and "model" properties are described in the section > > > "3.3.2.1 > > > Root Node Properties" of the "Device Tree Bindings: Linux on Power > > > Architecture > > > Reference" document: > > > > > > https://members.openpowerfoundation.org/wg/SYSSW/document/1455 > > > > I replied too early. As Maxiwell explained to me (thanks Max!), guest can > > end up > > having the following entries under /proc/device-tree/ (among other entries): > > > > $ cat host-serial > > 12A3B4C > > > > $ cat host-model > > 1234-56A > > > > $ cat system-id > > c7b62da9-3d0c-44f9-8edb-2318271f3c1a > > > > $ cat model > > IBM pSeries (emulated by qemu) > > > > Where: > > > > - host-serial/host-model: depend on "-M host-serial" and "-M host-model" > > machine options. > > > > - system-id: created when "-uuid " exists in qemu command line > > options. > > > > - model: hard-coded. > > > > With this patch, RTAS ibm,get-vpd call will return "system-id" and "model" > > from > > the host, not from the guest. I found this confusing. > > Hrm. I found the bit in LoPAPR describing how ibm,get-vpd operates, > but not something describing the actual data that appears within it. > Where's that described? It'd be nice to check if those values are > supposed to be describing the host or the guest. Are you asking about the fields of the ibm,vpd property? They are described in Table 11.2 "LoPAPR VPD Fields" of this LoPAPR document: https://members.openpowerfoundation.org/wg/SYSSW/document/1461 Is that what you were looking for? > > > > Perhaps we can trick ibm,get-vpd call to return "host-serial" and > > "host-model" > > values from the guest, which will hold safe values after commit > > 9e584f45868f6945c1282c938278038cba0e4af2 "ppc: add host-serial and > > host-model > > machine attributes (CVE-2019-8934)". > > Well, if it is supposed to be host values, then yes, absolutely, we > should be using the "host" values that the user supplies (if any). > > > What do you think? > > > > As to removing "host-serial" and "host-model", I am not entirely sure for > > what > > they are used. There should be a reason for
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Tue, Feb 26, 2019 at 04:11:40PM -0300, Murilo Opsfelder Araujo wrote: > On Tue, Feb 26, 2019 at 02:08:30PM -0300, Murilo Opsfelder Araujo wrote: > > Hi, Maxiwell. > > > > On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > > > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > > > > > Hi, Maxiwell. > > > > > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > > > guest to collect host information. It is disabled by default to > > > > > > avoid unwanted information leakage. To enable it, use: > > > > > > ‘-M pseries,vpd-export=on’ > > > > > > > > > > The patch for setting host-serial and host-model already landed > > > > > Gibson's > > > > > ppc-for-4.0 branch: > > > > > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > > > Author: Prasad J Pandit > > > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > > > > > ppc: add host-serial and host-model machine attributes > > > > > (CVE-2019-8934) > > > > > > > > > > > > > > > QEMU should only return host-serial and host-model from the host if > > > > > the > > > > > following combination of parameters are provided: > > > > > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > > > > > If host-serial or host-model are set with a user-string, ibm,get-vpd > > > > > should > > > > > honor these values and return them, not exposing host information by > > > > > accident. > > > > > > > > > > I'm not even sure if we need vpd-export= setting. Its logic > > > > > could be > > > > > derived from the presence of host-serial=passthrough and > > > > > host-model=passthrough > > > > > options. > > > > > > > > > > What do you think? > > > > > > > > That's an excellent point - I hadn't thought through the fact that > > > > this is the same information exposed by those properties. I do indeed > > > > think that exposing the same information set in those properties - and > > > > thereby avoiding the new machine option - would be a better plan. > > > > > > > > > > I saw that the patch was applied. So I will work in another patch > > > to use these properties and remove the export-vpd option. > > > > > > Another thing that I thought the fact that 'host-serial' and 'host-model' > > > nodes in Device Tree are not in accordance with LoPAPR document. What > > > you think in use only get-vpd to get these information and remove > > > nodes from device tree? > > > > Both "system-id" and "model" properties are described in the section > > "3.3.2.1 > > Root Node Properties" of the "Device Tree Bindings: Linux on Power > > Architecture > > Reference" document: > > > > https://members.openpowerfoundation.org/wg/SYSSW/document/1455 > > I replied too early. As Maxiwell explained to me (thanks Max!), guest can end > up > having the following entries under /proc/device-tree/ (among other entries): > > $ cat host-serial > 12A3B4C > > $ cat host-model > 1234-56A > > $ cat system-id > c7b62da9-3d0c-44f9-8edb-2318271f3c1a > > $ cat model > IBM pSeries (emulated by qemu) > > Where: > > - host-serial/host-model: depend on "-M host-serial" and "-M host-model" > machine options. > > - system-id: created when "-uuid " exists in qemu command line options. > > - model: hard-coded. > > With this patch, RTAS ibm,get-vpd call will return "system-id" and "model" > from > the host, not from the guest. I found this confusing. Hrm. I found the bit in LoPAPR describing how ibm,get-vpd operates, but not something describing the actual data that appears within it. Where's that described? It'd be nice to check if those values are supposed to be describing the host or the guest. > Perhaps we can trick ibm,get-vpd call to return "host-serial" and "host-model" > values from the guest, which will hold safe values after commit > 9e584f45868f6945c1282c938278038cba0e4af2 "ppc: add host-serial and host-model > machine attributes (CVE-2019-8934)". Well, if it is supposed to be host values, then yes, absolutely, we should be using the "host" values that the user supplies (if any). > What do you think? > > As to removing "host-serial" and "host-model", I am not entirely sure for what > they are used. There should be a reason for them to exist. > -- David Gibson| I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson signature.asc Description: PGP signature
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > > > Hi, Maxiwell. > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > guest to collect host information. It is disabled by default to > > > > avoid unwanted information leakage. To enable it, use: > > > > ‘-M pseries,vpd-export=on’ > > > > > > The patch for setting host-serial and host-model already landed Gibson's > > > ppc-for-4.0 branch: > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > Author: Prasad J Pandit > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > ppc: add host-serial and host-model machine attributes > > > (CVE-2019-8934) > > > > > > > > > QEMU should only return host-serial and host-model from the host if the > > > following combination of parameters are provided: > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > If host-serial or host-model are set with a user-string, ibm,get-vpd > > > should > > > honor these values and return them, not exposing host information by > > > accident. > > > > > > I'm not even sure if we need vpd-export= setting. Its logic could be > > > derived from the presence of host-serial=passthrough and > > > host-model=passthrough > > > options. > > > > > > What do you think? > > > > That's an excellent point - I hadn't thought through the fact that > > this is the same information exposed by those properties. I do indeed > > think that exposing the same information set in those properties - and > > thereby avoiding the new machine option - would be a better plan. > > I saw that the patch was applied. So I will work in another patch > to use these properties and remove the export-vpd option. Sorry, should have said. I did apply it, but I pulled it out again because of the point above. > Another thing that I thought the fact that 'host-serial' and 'host-model' > nodes in Device Tree are not in accordance with LoPAPR document. What > you think in use only get-vpd to get these information and remove > nodes from device tree? > > > -- David Gibson| I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson signature.asc Description: PGP signature
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Tue, Feb 26, 2019 at 02:08:30PM -0300, Murilo Opsfelder Araujo wrote: > Hi, Maxiwell. > > On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > > > > Hi, Maxiwell. > > > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > > guest to collect host information. It is disabled by default to > > > > > avoid unwanted information leakage. To enable it, use: > > > > > ‘-M pseries,vpd-export=on’ > > > > > > > > The patch for setting host-serial and host-model already landed Gibson's > > > > ppc-for-4.0 branch: > > > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > > Author: Prasad J Pandit > > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > > > ppc: add host-serial and host-model machine attributes > > > > (CVE-2019-8934) > > > > > > > > > > > > QEMU should only return host-serial and host-model from the host if the > > > > following combination of parameters are provided: > > > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > > > If host-serial or host-model are set with a user-string, ibm,get-vpd > > > > should > > > > honor these values and return them, not exposing host information by > > > > accident. > > > > > > > > I'm not even sure if we need vpd-export= setting. Its logic could > > > > be > > > > derived from the presence of host-serial=passthrough and > > > > host-model=passthrough > > > > options. > > > > > > > > What do you think? > > > > > > That's an excellent point - I hadn't thought through the fact that > > > this is the same information exposed by those properties. I do indeed > > > think that exposing the same information set in those properties - and > > > thereby avoiding the new machine option - would be a better plan. > > > > > > > I saw that the patch was applied. So I will work in another patch > > to use these properties and remove the export-vpd option. > > > > Another thing that I thought the fact that 'host-serial' and 'host-model' > > nodes in Device Tree are not in accordance with LoPAPR document. What > > you think in use only get-vpd to get these information and remove > > nodes from device tree? > > Both "system-id" and "model" properties are described in the section "3.3.2.1 > Root Node Properties" of the "Device Tree Bindings: Linux on Power > Architecture > Reference" document: > > https://members.openpowerfoundation.org/wg/SYSSW/document/1455 I replied too early. As Maxiwell explained to me (thanks Max!), guest can end up having the following entries under /proc/device-tree/ (among other entries): $ cat host-serial 12A3B4C $ cat host-model 1234-56A $ cat system-id c7b62da9-3d0c-44f9-8edb-2318271f3c1a $ cat model IBM pSeries (emulated by qemu) Where: - host-serial/host-model: depend on "-M host-serial" and "-M host-model" machine options. - system-id: created when "-uuid " exists in qemu command line options. - model: hard-coded. With this patch, RTAS ibm,get-vpd call will return "system-id" and "model" from the host, not from the guest. I found this confusing. Perhaps we can trick ibm,get-vpd call to return "host-serial" and "host-model" values from the guest, which will hold safe values after commit 9e584f45868f6945c1282c938278038cba0e4af2 "ppc: add host-serial and host-model machine attributes (CVE-2019-8934)". What do you think? As to removing "host-serial" and "host-model", I am not entirely sure for what they are used. There should be a reason for them to exist. -- Murilo
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
Hi, Maxiwell. On Tue, Feb 26, 2019 at 11:21:26AM -0300, Maxiwell S. Garcia wrote: > On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > > > Hi, Maxiwell. > > > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > > guest to collect host information. It is disabled by default to > > > > avoid unwanted information leakage. To enable it, use: > > > > ‘-M pseries,vpd-export=on’ > > > > > > The patch for setting host-serial and host-model already landed Gibson's > > > ppc-for-4.0 branch: > > > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > > Author: Prasad J Pandit > > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > > > ppc: add host-serial and host-model machine attributes > > > (CVE-2019-8934) > > > > > > > > > QEMU should only return host-serial and host-model from the host if the > > > following combination of parameters are provided: > > > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > > > If host-serial or host-model are set with a user-string, ibm,get-vpd > > > should > > > honor these values and return them, not exposing host information by > > > accident. > > > > > > I'm not even sure if we need vpd-export= setting. Its logic could be > > > derived from the presence of host-serial=passthrough and > > > host-model=passthrough > > > options. > > > > > > What do you think? > > > > That's an excellent point - I hadn't thought through the fact that > > this is the same information exposed by those properties. I do indeed > > think that exposing the same information set in those properties - and > > thereby avoiding the new machine option - would be a better plan. > > > > I saw that the patch was applied. So I will work in another patch > to use these properties and remove the export-vpd option. > > Another thing that I thought the fact that 'host-serial' and 'host-model' > nodes in Device Tree are not in accordance with LoPAPR document. What > you think in use only get-vpd to get these information and remove > nodes from device tree? Both "system-id" and "model" properties are described in the section "3.3.2.1 Root Node Properties" of the "Device Tree Bindings: Linux on Power Architecture Reference" document: https://members.openpowerfoundation.org/wg/SYSSW/document/1455 -- Murilo
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Tue, Feb 26, 2019 at 02:21:03PM +1100, David Gibson wrote: > On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > > Hi, Maxiwell. > > > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > > guest to collect host information. It is disabled by default to > > > avoid unwanted information leakage. To enable it, use: > > > ‘-M pseries,vpd-export=on’ > > > > The patch for setting host-serial and host-model already landed Gibson's > > ppc-for-4.0 branch: > > > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > > Author: Prasad J Pandit > > Date: Mon Feb 18 23:43:49 2019 +0530 > > > > ppc: add host-serial and host-model machine attributes (CVE-2019-8934) > > > > > > QEMU should only return host-serial and host-model from the host if the > > following combination of parameters are provided: > > > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > > > If host-serial or host-model are set with a user-string, ibm,get-vpd should > > honor these values and return them, not exposing host information by > > accident. > > > > I'm not even sure if we need vpd-export= setting. Its logic could be > > derived from the presence of host-serial=passthrough and > > host-model=passthrough > > options. > > > > What do you think? > > That's an excellent point - I hadn't thought through the fact that > this is the same information exposed by those properties. I do indeed > think that exposing the same information set in those properties - and > thereby avoiding the new machine option - would be a better plan. > I saw that the patch was applied. So I will work in another patch to use these properties and remove the export-vpd option. Another thing that I thought the fact that 'host-serial' and 'host-model' nodes in Device Tree are not in accordance with LoPAPR document. What you think in use only get-vpd to get these information and remove nodes from device tree? > -- > David Gibson | I'll have my music baroque, and my code > david AT gibson.dropbear.id.au| minimalist, thank you. NOT _the_ > _other_ > | _way_ _around_! > http://www.ozlabs.org/~dgibson
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
On Mon, Feb 25, 2019 at 08:20:09PM -0300, Murilo Opsfelder Araujo wrote: > Hi, Maxiwell. > > On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote: > > This adds a handler for ibm,get-vpd RTAS calls, allowing pseries > > guest to collect host information. It is disabled by default to > > avoid unwanted information leakage. To enable it, use: > > ‘-M pseries,vpd-export=on’ > > The patch for setting host-serial and host-model already landed Gibson's > ppc-for-4.0 branch: > > commit 9e584f45868f6945c1282c938278038cba0e4af2 > Author: Prasad J Pandit > Date: Mon Feb 18 23:43:49 2019 +0530 > > ppc: add host-serial and host-model machine attributes (CVE-2019-8934) > > > QEMU should only return host-serial and host-model from the host if the > following combination of parameters are provided: > > -M host-serial=passthrough,host-model=passthrough,vpd-export=on > > If host-serial or host-model are set with a user-string, ibm,get-vpd should > honor these values and return them, not exposing host information by accident. > > I'm not even sure if we need vpd-export= setting. Its logic could be > derived from the presence of host-serial=passthrough and > host-model=passthrough > options. > > What do you think? That's an excellent point - I hadn't thought through the fact that this is the same information exposed by those properties. I do indeed think that exposing the same information set in those properties - and thereby avoiding the new machine option - would be a better plan. -- David Gibson| I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson signature.asc Description: PGP signature
Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr-rtas: add ibm, get-vpd RTAS interface
Hi, Maxiwell.
On Mon, Feb 25, 2019 at 01:23:25PM -0300, Maxiwell S. Garcia wrote:
> This adds a handler for ibm,get-vpd RTAS calls, allowing pseries
> guest to collect host information. It is disabled by default to
> avoid unwanted information leakage. To enable it, use:
> ‘-M pseries,vpd-export=on’
The patch for setting host-serial and host-model already landed Gibson's
ppc-for-4.0 branch:
commit 9e584f45868f6945c1282c938278038cba0e4af2
Author: Prasad J Pandit
Date: Mon Feb 18 23:43:49 2019 +0530
ppc: add host-serial and host-model machine attributes (CVE-2019-8934)
QEMU should only return host-serial and host-model from the host if the
following combination of parameters are provided:
-M host-serial=passthrough,host-model=passthrough,vpd-export=on
If host-serial or host-model are set with a user-string, ibm,get-vpd should
honor these values and return them, not exposing host information by accident.
I'm not even sure if we need vpd-export= setting. Its logic could be
derived from the presence of host-serial=passthrough and host-model=passthrough
options.
What do you think?
>
> Only the SE and TM keywords are returned at the moment:
> SE for Machine or Cabinet Serial Number and
> TM for Machine Type and Model.
>
> Powerpc-utils tools can dispatch RTAS calls to retrieve host
> information using this ibm,get-vpd interface. The 'host-serial'
> and 'host-model' nodes of device-tree hold the same information but
> in a static manner, which is useless after a migration operation.
>
> Signed-off-by: Maxiwell S. Garcia
> ---
> hw/ppc/spapr.c | 21 ++
> hw/ppc/spapr_rtas.c| 95 ++
> include/hw/ppc/spapr.h | 17 +++-
> 3 files changed, 132 insertions(+), 1 deletion(-)
>
> Update v2:
> - rtas_ibm_get_vpd(): fix initialization values
>
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index abf9ebce59..09fd9e2ebb 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -3026,6 +3026,20 @@ static char *spapr_get_fw_dev_path(FWPathProvider *p,
> BusState *bus,
> return NULL;
> }
>
> +static bool spapr_get_vpd_export(Object *obj, Error **errp)
> +{
> +sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
> +
> +return spapr->vpd_export;
> +}
> +
> +static void spapr_set_vpd_export(Object *obj, bool value, Error **errp)
> +{
> +sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
> +
> +spapr->vpd_export = value;
> +}
> +
> static char *spapr_get_kvm_type(Object *obj, Error **errp)
> {
> sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
> @@ -3150,6 +3164,7 @@ static void spapr_instance_init(Object *obj)
> sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
>
> spapr->htab_fd = -1;
> +spapr->vpd_export = false;
> spapr->use_hotplug_event_source = true;
> object_property_add_str(obj, "kvm-type",
> spapr_get_kvm_type, spapr_set_kvm_type, NULL);
> @@ -3182,6 +3197,12 @@ static void spapr_instance_init(Object *obj)
> object_property_add_bool(obj, "vfio-no-msix-emulation",
> spapr_get_msix_emulation, NULL, NULL);
>
> +object_property_add_bool(obj, "vpd-export", spapr_get_vpd_export,
> + spapr_set_vpd_export, NULL);
> +object_property_set_description(obj, "vpd-export",
> +"Export Host's VPD information to guest",
> +_abort);
> +
> /* The machine class defines the default interrupt controller mode */
> spapr->irq = smc->irq;
> object_property_add_str(obj, "ic-mode", spapr_get_ic_mode,
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index d6a0952154..fbf589c502 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -287,6 +287,99 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU
> *cpu,
> rtas_st(rets, 0, ret);
> }
>
> +static inline int vpd_st(target_ulong addr, target_ulong len,
> + const void *val, uint16_t val_len)
> +{
> +hwaddr phys = ppc64_phys_to_real(addr);
> +if (len < val_len) {
> +return RTAS_OUT_PARAM_ERROR;
> +}
> +cpu_physical_memory_write(phys, val, val_len);
> +return RTAS_OUT_SUCCESS;
> +}
> +
> +static inline void vpd_ret(target_ulong rets, const int status,
> + const int next_seq_number, const int
> bytes_returned)
> +{
> +rtas_st(rets, 0, status);
> +rtas_st(rets, 1, next_seq_number);
> +rtas_st(rets, 2, bytes_returned);
> +}
> +
> +static void rtas_ibm_get_vpd(PowerPCCPU *cpu,
> + sPAPRMachineState *spapr,
> + uint32_t token, uint32_t nargs,
> + target_ulong args,
> + uint32_t nret, target_ulong rets)
> +{
> +sPAPRMachineState *sm = SPAPR_MACHINE(spapr);
> +target_ulong loc_code_addr;
> +target_ulong work_area_addr;
> +target_ulong
