Commit Graph

14 Commits

Author SHA1 Message Date
Tom Lendacky
87af9b0b45 crypto: ccp - During shutdown, check SEV data pointer before using
[ Upstream commit 1b05ece0c931536c0a38a9385e243a7962e933f6 ]

On shutdown, each CCP device instance performs shutdown processing.
However, __sev_platform_shutdown_locked() uses the controlling psp
structure to obtain the pointer to the sev_device structure. However,
during driver initialization, it is possible that an error can be received
from the firmware that results in the sev_data pointer being cleared from
the controlling psp structure. The __sev_platform_shutdown_locked()
function does not check for this situation and will segfault.

While not common, this scenario should be accounted for. Add a check for a
NULL sev_device structure before attempting to use it.

Fixes: 5441a07a127f ("crypto: ccp - shutdown SEV firmware on kexec")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:15:41 +02:00
Brijesh Singh
6cae39f457 crypto: ccp - shutdown SEV firmware on kexec
commit 5441a07a127f106c9936e4f9fa1a8a93e3f31828 upstream.

The commit 97f9ac3db6 ("crypto: ccp - Add support for SEV-ES to the
PSP driver") added support to allocate Trusted Memory Region (TMR)
used during the SEV-ES firmware initialization. The TMR gets locked
during the firmware initialization and unlocked during the shutdown.
While the TMR is locked, access to it is disallowed.

Currently, the CCP driver does not shutdown the firmware during the
kexec reboot, leaving the TMR memory locked.

Register a callback to shutdown the SEV firmware on the kexec boot.

Fixes: 97f9ac3db6 ("crypto: ccp - Add support for SEV-ES to the PSP driver")
Reported-by: Lucas Nussbaum <lucas.nussbaum@inria.fr>
Tested-by: Lucas Nussbaum <lucas.nussbaum@inria.fr>
Cc: <stable@kernel.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-18 13:40:09 +02:00
Joerg Roedel
123c1b05b0 crypto: ccp - Annotate SEV Firmware file names
commit c8671c7dc7d51125ab9f651697866bf4a9132277 upstream.

Annotate the firmware files CCP might need using MODULE_FIRMWARE().
This will get them included into an initrd when CCP is also included
there. Otherwise the CCP module will not find its firmware when loaded
before the root-fs is mounted.
This can cause problems when the pre-loaded SEV firmware is too old to
support current SEV and SEV-ES virtualization features.

Fixes: e93720606e ("crypto: ccp - Allow SEV firmware to be chosen based on Family and Model")
Cc: stable@vger.kernel.org # v4.20+
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 16:55:39 +02:00
Sean Christopherson
f3a5dee0f3 crypto: ccp: Free SEV device if SEV init fails
[ Upstream commit b61a9071dc72a3c709192c0c00ab87c2b3de1d94 ]

Free the SEV device if later initialization fails.  The memory isn't
technically leaked as it's tracked in the top-level device's devres
list, but unless the top-level device is removed, the memory won't be
freed and is effectively leaked.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210406224952.4177376-2-seanjc@google.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:12:58 +02:00
Sean Christopherson
e606073b77 crypto: ccp: Detect and reject "invalid" addresses destined for PSP
[ Upstream commit 74c1f1366eb7714b8b211554f6c5cee315ff3fbc ]

Explicitly reject using pointers that are not virt_to_phys() friendly
as the source for SEV commands that are sent to the PSP.  The PSP works
with physical addresses, and __pa()/virt_to_phys() will not return the
correct address in these cases, e.g. for a vmalloc'd pointer.  At best,
the bogus address will cause the command to fail, and at worst lead to
system instability.

While it's unlikely that callers will deliberately use a bad pointer for
SEV buffers, a caller can easily use a vmalloc'd pointer unknowingly when
running with CONFIG_VMAP_STACK=y as it's not obvious that putting the
command buffers on the stack would be bad.  The command buffers are
relative  small and easily fit on the stack, and the APIs to do not
document that the incoming pointer must be a physically contiguous,
__pa() friendly pointer.

Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Fixes: 200664d523 ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210406224952.4177376-3-seanjc@google.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:41 +02:00
Herbert Xu
376bd28d03 crypto: ccp - Fix sparse warnings in sev-dev
This patch fixes a bunch of sparse warnings in sev-dev where the
__user marking is incorrectly handled.

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 7360e4b143 ("crypto: ccp: Implement SEV_PEK_CERT_IMPORT...")
Fixes: e799035609 ("crypto: ccp: Implement SEV_PEK_CSR ioctl...")
Fixes: 76a2b524a4 ("crypto: ccp: Implement SEV_PDH_CERT_EXPORT...")
Fixes: d6112ea0cb ("crypto: ccp - introduce SEV_GET_ID2 command")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-06-15 17:38:53 +10:00
Linus Torvalds
e0cd920687 Merge branch 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess/access_ok updates from Al Viro:
 "Removals of trivially pointless access_ok() calls.

  Note: the fiemap stuff was removed from the series, since they are
  duplicates with part of ext4 series carried in Ted's tree"

* 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vmci_host: get rid of pointless access_ok()
  hfi1: get rid of pointless access_ok()
  usb: get rid of pointless access_ok() calls
  lpfc_debugfs: get rid of pointless access_ok()
  efi_test: get rid of pointless access_ok()
  drm_read(): get rid of pointless access_ok()
  via-pmu: don't bother with access_ok()
  drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok()
  omapfb: get rid of pointless access_ok() calls
  amifb: get rid of pointless access_ok() calls
  drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok()
  drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok()
  cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok()
  nvram: drop useless access_ok()
  n_hdlc_tty_read(): remove pointless access_ok()
  tomoyo_write_control(): get rid of pointless access_ok()
  btrfs_ioctl_send(): don't bother with access_ok()
  fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade...
  dlmfs_file_write(): get rid of pointless access_ok()
2020-06-01 16:09:43 -07:00
Al Viro
835ae3bb53 drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok()
Contrary to the comments, those do *NOT* verify anything about
writability of memory, etc.

In all cases addresses are passed only to copy_to_user().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29 11:05:54 -04:00
Tom Lendacky
97f9ac3db6 crypto: ccp - Add support for SEV-ES to the PSP driver
To provide support for SEV-ES, the hypervisor must provide an area of
memory to the PSP. Once this Trusted Memory Region (TMR) is provided to
the PSP, the contents of this area of memory are no longer available to
the x86.

Update the PSP driver to allocate a 1MB region for the TMR that is 1MB
aligned and then provide it to the PSP through the SEV INIT command.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-04-30 15:19:33 +10:00
Connor Kuehl
b610281358 crypto: ccp - use file mode for sev ioctl permissions
Instead of using CAP_SYS_ADMIN which is restricted to the root user,
check the file mode for write permissions before executing commands that
can affect the platform. This allows for more fine-grained access
control to the SEV ioctl interface. This would allow a SEV-only user
or group the ability to administer the platform without requiring them
to be root or granting them overly powerful permissions.

For example:

chown root:root /dev/sev
chmod 600 /dev/sev
setfacl -m g:sev:r /dev/sev
setfacl -m g:sev-admin:rw /dev/sev

In this instance, members of the "sev-admin" group have the ability to
perform all ioctl calls (including the ones that modify platform state).
Members of the "sev" group only have access to the ioctls that do not
modify the platform state.

This also makes opening "/dev/sev" more consistent with how file
descriptors are usually handled. By only checking for CAP_SYS_ADMIN,
the file descriptor could be opened read-only but could still execute
ioctls that modify the platform state. This patch enforces that the file
descriptor is opened with write privileges if it is going to be used to
modify the platform state.

This flexibility is completely opt-in, and if it is not desirable by
the administrator then they do not need to give anyone else access to
/dev/sev.

Signed-off-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-03-12 23:00:15 +11:00
John Allen
1f14b57ffc crypto: ccp - Cleanup misc_dev on sev_exit()
Explicitly free and clear misc_dev in sev_exit(). Since devm_kzalloc()
associates misc_dev with the first device that gets probed, change from
devm_kzalloc() to kzalloc() and explicitly free memory in sev_exit() as
the first device probed is not guaranteed to be the last device released.
To ensure that the variable gets properly set to NULL, remove the local
definition of misc_dev.

Fixes: 200664d523 ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support")
Signed-off-by: John Allen <john.allen@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-03-12 23:00:12 +11:00
Rijo Thomas
6eb0cc72bc crypto: ccp - move SEV vdata to a dedicated data structure
PSP can support both SEV and TEE interface. Therefore, move
SEV specific registers to a dedicated data structure.
TEE interface specific registers will be added in a later
patch.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-20 14:58:32 +08:00
Rijo Thomas
b93566f1bb crypto: ccp - create a generic psp-dev file
The PSP (Platform Security Processor) provides support for key management
commands in Secure Encrypted Virtualization (SEV) mode, along with
software-based Trusted Execution Environment (TEE) to enable third-party
Trusted Applications.

Therefore, introduce psp-dev.c and psp-dev.h files, which can invoke
SEV (or TEE) initialization based on platform feature support.

TEE interface support will be introduced in a later patch.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-20 14:58:32 +08:00
Rijo Thomas
9b67d08dbc crypto: ccp - rename psp-dev files to sev-dev
This is a preliminary patch for creating a generic PSP device driver
file, which will have support for both SEV and TEE (Trusted Execution
Environment) interface.

This patch does not introduce any new functionality, but simply renames
psp-dev.c and psp-dev.h files to sev-dev.c and sev-dev.h files
respectively.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-20 14:52:59 +08:00