kernel.git/drivers/crypto/ccp/sev-dev.c, branch linux-5.10.y

crypto: ccp - Properly unregister /dev/sev on sev PLATFORM_STATUS failure

2024-10-17T13:08:01Z

commit ce3d2d6b150ba8528f3218ebf0cee2c2c572662d upstream. In case of sev PLATFORM_STATUS failure, sev_get_api_version() fails resulting in sev_data field of psp_master nulled out. This later becomes a problem when unloading the ccp module because the device has not been unregistered (via misc_deregister()) before clearing the sev_data field of psp_master. As a result, on reloading the ccp module, a duplicate device issue is encountered as can be seen from the dmesg log below. on reloading ccp module via modprobe ccp Call Trace: dump_stack_lvl+0xd7/0xf0 dump_stack+0x10/0x20 sysfs_warn_dup+0x5c/0x70 sysfs_create_dir_ns+0xbc/0xd kobject_add_internal+0xb1/0x2f0 kobject_add+0x7a/0xe0 ? srso_alias_return_thunk+0x5/0xfbef5 ? get_device_parent+0xd4/0x1e0 ? __pfx_klist_children_get+0x10/0x10 device_add+0x121/0x870 ? srso_alias_return_thunk+0x5/0xfbef5 device_create_groups_vargs+0xdc/0x100 device_create_with_groups+0x3f/0x60 misc_register+0x13b/0x1c0 sev_dev_init+0x1d4/0x290 [ccp] psp_dev_init+0x136/0x300 [ccp] sp_init+0x6f/0x80 [ccp] sp_pci_probe+0x2a6/0x310 [ccp] ? srso_alias_return_thunk+0x5/0xfbef5 local_pci_probe+0x4b/0xb0 work_for_cpu_fn+0x1a/0x30 process_one_work+0x203/0x600 worker_thread+0x19e/0x350 ? __pfx_worker_thread+0x10/0x10 kthread+0xeb/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x3c/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 kobject: kobject_add_internal failed for sev with -EEXIST, don't try to register things with the same name in the same directory. ccp 0000:22:00.1: sev initialization failed ccp 0000:22:00.1: psp initialization failed ccp 0000:a2:00.1: no command queues available ccp 0000:a2:00.1: psp enabled Address this issue by unregistering the /dev/sev before clearing out sev_data in case of PLATFORM_STATUS failure. Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support") Cc: stable@vger.kernel.org Signed-off-by: Pavan Kumar Paluri Acked-by: Tom Lendacky Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

crypto: ccp - Fix null pointer dereference in __sev_platform_shutdown_locked

2024-02-23T07:42:28Z

commit ccb88e9549e7cfd8bcd511c538f437e20026e983 upstream. The SEV platform device can be shutdown with a null psp_master, e.g., using DEBUG_TEST_DRIVER_REMOVE. Found using KASAN: [ 137.148210] ccp 0000:23:00.1: enabling device (0000 -> 0002) [ 137.162647] ccp 0000:23:00.1: no command queues available [ 137.170598] ccp 0000:23:00.1: sev enabled [ 137.174645] ccp 0000:23:00.1: psp enabled [ 137.178890] general protection fault, probably for non-canonical address 0xdffffc000000001e: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN NOPTI [ 137.182693] KASAN: null-ptr-deref in range [0x00000000000000f0-0x00000000000000f7] [ 137.182693] CPU: 93 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc1+ #311 [ 137.182693] RIP: 0010:__sev_platform_shutdown_locked+0x51/0x180 [ 137.182693] Code: 08 80 3c 08 00 0f 85 0e 01 00 00 48 8b 1d 67 b6 01 08 48 b8 00 00 00 00 00 fc ff df 48 8d bb f0 00 00 00 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 fe 00 00 00 48 8b 9b f0 00 00 00 48 85 db 74 2c [ 137.182693] RSP: 0018:ffffc900000cf9b0 EFLAGS: 00010216 [ 137.182693] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 000000000000001e [ 137.182693] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 00000000000000f0 [ 137.182693] RBP: ffffc900000cf9c8 R08: 0000000000000000 R09: fffffbfff58f5a66 [ 137.182693] R10: ffffc900000cf9c8 R11: ffffffffac7ad32f R12: ffff8881e5052c28 [ 137.182693] R13: ffff8881e5052c28 R14: ffff8881758e43e8 R15: ffffffffac64abf8 [ 137.182693] FS: 0000000000000000(0000) GS:ffff889de7000000(0000) knlGS:0000000000000000 [ 137.182693] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 137.182693] CR2: 0000000000000000 CR3: 0000001cf7c7e000 CR4: 0000000000350ef0 [ 137.182693] Call Trace: [ 137.182693] [ 137.182693] ? show_regs+0x6c/0x80 [ 137.182693] ? __die_body+0x24/0x70 [ 137.182693] ? die_addr+0x4b/0x80 [ 137.182693] ? exc_general_protection+0x126/0x230 [ 137.182693] ? asm_exc_general_protection+0x2b/0x30 [ 137.182693] ? __sev_platform_shutdown_locked+0x51/0x180 [ 137.182693] sev_firmware_shutdown.isra.0+0x1e/0x80 [ 137.182693] sev_dev_destroy+0x49/0x100 [ 137.182693] psp_dev_destroy+0x47/0xb0 [ 137.182693] sp_destroy+0xbb/0x240 [ 137.182693] sp_pci_remove+0x45/0x60 [ 137.182693] pci_device_remove+0xaa/0x1d0 [ 137.182693] device_remove+0xc7/0x170 [ 137.182693] really_probe+0x374/0xbe0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] __driver_probe_device+0x199/0x460 [ 137.182693] driver_probe_device+0x4e/0xd0 [ 137.182693] __driver_attach+0x191/0x3d0 [ 137.182693] ? __pfx___driver_attach+0x10/0x10 [ 137.182693] bus_for_each_dev+0x100/0x190 [ 137.182693] ? __pfx_bus_for_each_dev+0x10/0x10 [ 137.182693] ? __kasan_check_read+0x15/0x20 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? _raw_spin_unlock+0x27/0x50 [ 137.182693] driver_attach+0x41/0x60 [ 137.182693] bus_add_driver+0x2a8/0x580 [ 137.182693] driver_register+0x141/0x480 [ 137.182693] __pci_register_driver+0x1d6/0x2a0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? esrt_sysfs_init+0x1cd/0x5d0 [ 137.182693] ? __pfx_sp_mod_init+0x10/0x10 [ 137.182693] sp_pci_init+0x22/0x30 [ 137.182693] sp_mod_init+0x14/0x30 [ 137.182693] ? __pfx_sp_mod_init+0x10/0x10 [ 137.182693] do_one_initcall+0xd1/0x470 [ 137.182693] ? __pfx_do_one_initcall+0x10/0x10 [ 137.182693] ? parameq+0x80/0xf0 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] ? __kmalloc+0x3b0/0x4e0 [ 137.182693] ? kernel_init_freeable+0x92d/0x1050 [ 137.182693] ? kasan_populate_vmalloc_pte+0x171/0x190 [ 137.182693] ? srso_return_thunk+0x5/0x5f [ 137.182693] kernel_init_freeable+0xa64/0x1050 [ 137.182693] ? __pfx_kernel_init+0x10/0x10 [ 137.182693] kernel_init+0x24/0x160 [ 137.182693] ? __switch_to_asm+0x3e/0x70 [ 137.182693] ret_from_fork+0x40/0x80 [ 137.182693] ? __pfx_kernel_init+0x10/0x10 [ 137.182693] ret_from_fork_asm+0x1b/0x30 [ 137.182693] [ 137.182693] Modules linked in: [ 137.538483] ---[ end trace 0000000000000000 ]--- Fixes: 1b05ece0c931 ("crypto: ccp - During shutdown, check SEV data pointer before using") Cc: stable@vger.kernel.org Reviewed-by: Mario Limonciello Signed-off-by: Kim Phillips Reviewed-by: Liam Merwick Acked-by: John Allen Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

crypto: ccp: Play nice with vmalloc'd memory for SEV command structs

2023-06-09T08:30:18Z

commit 8347b99473a313be6549a5b940bc3c56a71be81c upstream. Copy the incoming @data comman to an internal buffer so that callers can put SEV command buffers on the stack without running afoul of CONFIG_VMAP_STACK=y, i.e. without bombing on vmalloc'd pointers. As of today, the largest supported command takes a 68 byte buffer, i.e. pretty much every command can be put on the stack. Because sev_cmd_mutex is held for the entirety of a transaction, only a single bounce buffer is required. Use the internal buffer unconditionally, as the majority of in-kernel users will soon switch to using the stack. At that point, checking virt_addr_valid() becomes (negligible) overhead in most cases, and supporting both paths slightly increases complexity. Since the commands are all quite small, the cost of the copies is insignificant compared to the latency of communicating with the PSP. Allocate a full page for the buffer as opportunistic preparation for SEV-SNP, which requires the command buffer to be in firmware state for commands that trigger memory writes from the PSP firmware. Using a full page now will allow SEV-SNP support to simply transition the page as needed. Cc: Brijesh Singh Cc: Borislav Petkov Cc: Tom Lendacky Cc: Christophe Leroy Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-5-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

crypto: ccp: Reject SEV commands with mismatching command buffer

2023-06-09T08:30:18Z

commit d5760dee127bf6f390b05e747369d7c37ae1a7b8 upstream. WARN on and reject SEV commands that provide a valid data pointer, but do not have a known, non-zero length. And conversely, reject commands that take a command buffer but none is provided (data is null). Aside from sanity checking input, disallowing a non-null pointer without a non-zero size will allow a future patch to cleanly handle vmalloc'd data by copying the data to an internal __pa() friendly buffer. Note, this also effectively prevents callers from using commands that have a non-zero length and are not known to the kernel. This is not an explicit goal, but arguably the side effect is a good thing from the kernel's perspective. Cc: Brijesh Singh Cc: Borislav Petkov Cc: Tom Lendacky Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-4-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

crypto: ccp - Flush the SEV-ES TMR memory before giving it to firmware

2023-03-11T15:39:25Z

[ Upstream commit 46a334a98f585ef78d51d8f5736596887bdd7f54 ] Perform a cache flush on the SEV-ES TMR memory after allocation to prevent any possibility of the firmware encountering an error should dirty cache lines be present. Use clflush_cache_range() to flush the SEV-ES TMR memory. Fixes: 97f9ac3db661 ("crypto: ccp - Add support for SEV-ES to the PSP driver") Signed-off-by: Tom Lendacky Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

crypto: ccp - Refactor out sev_fw_alloc()

2023-03-11T15:39:24Z

[ Upstream commit cc17982d58d1e67eab831e7023ede999dda56173 ] Create a helper function sev_fw_alloc() which can be used to allocate aligned memory regions for use by the PSP firmware. Currently only used for the SEV-ES TMR region but will be used for the SEV_INIT_EX NV memory region. Signed-off-by: Peter Gonda Reviewed-by: Marc Orr Acked-by: David Rientjes Acked-by: Brijesh Singh Cc: Tom Lendacky Cc: Brijesh Singh Cc: Marc Orr Cc: Joerg Roedel Cc: Herbert Xu Cc: David Rientjes Cc: John Allen Cc: "David S. Miller" Cc: Paolo Bonzini Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu Stable-dep-of: 46a334a98f58 ("crypto: ccp - Flush the SEV-ES TMR memory before giving it to firmware") Signed-off-by: Sasha Levin

crypto: ccp - Avoid page allocation failure warning for SEV_GET_ID2

2023-03-11T15:39:20Z

[ Upstream commit 91dfd98216d817ec5f1c55890bacb7b4fe9b068a ] For SEV_GET_ID2, the user provided length does not have a specified limitation because the length of the ID may change in the future. The kernel memory allocation, however, is implicitly limited to 4MB on x86 by the page allocator, otherwise the kzalloc() will fail. When this happens, it is best not to spam the kernel log with the warning. Simply fail the allocation and return ENOMEM to the user. Fixes: d6112ea0cb34 ("crypto: ccp - introduce SEV_GET_ID2 command") Reported-by: Andy Nguyen Reported-by: Peter Gonda Suggested-by: Herbert Xu Signed-off-by: David Rientjes Acked-by: Tom Lendacky Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

crypto: ccp - Use kzalloc for sev ioctl interfaces to prevent kernel memory leak

2023-03-11T15:39:20Z

[ Upstream commit 13dc15a3f5fd7f884e4bfa8c011a0ae868df12ae ] For some sev ioctl interfaces, input may be passed that is less than or equal to SEV_FW_BLOB_MAX_SIZE, but larger than the data that PSP firmware returns. In this case, kmalloc will allocate memory that is the size of the input rather than the size of the data. Since PSP firmware doesn't fully overwrite the buffer, the sev ioctl interfaces with the issue may return uninitialized slab memory. Currently, all of the ioctl interfaces in the ccp driver are safe, but to prevent future problems, change all ioctl interfaces that allocate memory with kmalloc to use kzalloc and memset the data buffer to zero in sev_ioctl_do_platform_status. Fixes: 38103671aad3 ("crypto: ccp: Use the stack and common buffer for status commands") Fixes: e799035609e15 ("crypto: ccp: Implement SEV_PEK_CSR ioctl command") Fixes: 76a2b524a4b1d ("crypto: ccp: Implement SEV_PDH_CERT_EXPORT ioctl command") Fixes: d6112ea0cb344 ("crypto: ccp - introduce SEV_GET_ID2 command") Cc: stable@vger.kernel.org Reported-by: Andy Nguyen Suggested-by: David Rientjes Suggested-by: Peter Gonda Signed-off-by: John Allen Reviewed-by: Peter Gonda Acked-by: David Rientjes Signed-off-by: Herbert Xu Stable-dep-of: 91dfd98216d8 ("crypto: ccp - Avoid page allocation failure warning for SEV_GET_ID2") Signed-off-by: Sasha Levin

crypto: ccp: Use the stack and common buffer for status commands

2023-03-11T15:39:20Z

[ Upstream commit 38103671aad38e888743dd26c767869cfc15adca ] Drop the dedicated status_cmd_buf and instead use a local variable for PLATFORM_STATUS. Now that the low level helper uses an internal buffer for all commands, using the stack for the upper layers is safe even when running with CONFIG_VMAP_STACK=y. Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-7-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Stable-dep-of: 91dfd98216d8 ("crypto: ccp - Avoid page allocation failure warning for SEV_GET_ID2") Signed-off-by: Sasha Levin

crypto: ccp: Use the stack for small SEV command buffers

2023-03-11T15:39:20Z

[ Upstream commit e4a9af799e5539b0feb99571f0aaed5a3c81dc5a ] For commands with small input/output buffers, use the local stack to "allocate" the structures used to communicate with the PSP. Now that __sev_do_cmd_locked() gracefully handles vmalloc'd buffers, there's no reason to avoid using the stack, e.g. CONFIG_VMAP_STACK=y will just work. Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-6-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Stable-dep-of: 91dfd98216d8 ("crypto: ccp - Avoid page allocation failure warning for SEV_GET_ID2") Signed-off-by: Sasha Levin