From 14cb5d83068ecf15d2da6f7d0e9ea9edbcbc0457 Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Fri, 7 Mar 2025 00:28:46 +0000 Subject: x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range() Xen doesn't offer MSR_FAM10H_MMIO_CONF_BASE to all guests. This results in the following warning: unchecked MSR access error: RDMSR from 0xc0010058 at rIP: 0xffffffff8101d19f (xen_do_read_msr+0x7f/0xa0) Call Trace: xen_read_msr+0x1e/0x30 amd_get_mmconfig_range+0x2b/0x80 quirk_amd_mmconfig_area+0x28/0x100 pnp_fixup_device+0x39/0x50 __pnp_add_device+0xf/0x150 pnp_add_device+0x3d/0x100 pnpacpi_add_device_handler+0x1f9/0x280 acpi_ns_get_device_callback+0x104/0x1c0 acpi_ns_walk_namespace+0x1d0/0x260 acpi_get_devices+0x8a/0xb0 pnpacpi_init+0x50/0x80 do_one_initcall+0x46/0x2e0 kernel_init_freeable+0x1da/0x2f0 kernel_init+0x16/0x1b0 ret_from_fork+0x30/0x50 ret_from_fork_asm+0x1b/0x30 based on quirks for a "PNP0c01" device. Treating MMCFG as disabled is the right course of action, so no change is needed there. This was most likely exposed by fixing the Xen MSR accessors to not be silently-safe. Fixes: 3fac3734c43a ("xen/pv: support selecting safe/unsafe msr accesses") Signed-off-by: Andrew Cooper Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20250307002846.3026685-1-andrew.cooper3@citrix.com --- arch/x86/kernel/amd_nb.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c index 11fac09e3a8c..67e773744edb 100644 --- a/arch/x86/kernel/amd_nb.c +++ b/arch/x86/kernel/amd_nb.c @@ -143,7 +143,6 @@ bool __init early_is_amd_nb(u32 device) struct resource *amd_get_mmconfig_range(struct resource *res) { - u32 address; u64 base, msr; unsigned int segn_busn_bits; @@ -151,13 +150,11 @@ struct resource *amd_get_mmconfig_range(struct resource *res) boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) return NULL; - /* assume all cpus from fam10h have mmconfig */ - if (boot_cpu_data.x86 < 0x10) + /* Assume CPUs from Fam10h have mmconfig, although not all VMs do */ + if (boot_cpu_data.x86 < 0x10 || + rdmsrl_safe(MSR_FAM10H_MMIO_CONF_BASE, &msr)) return NULL; - address = MSR_FAM10H_MMIO_CONF_BASE; - rdmsrl(address, msr); - /* mmconfig is not enabled */ if (!(msr & FAM10H_MMIO_CONF_ENABLE)) return NULL; -- cgit v1.2.3 From ac7c06acaa3738b38e83815ac0f07140ad320f13 Mon Sep 17 00:00:00 2001 From: Nikunj A Dadhania Date: Thu, 6 Mar 2025 19:17:21 +1100 Subject: virt: sev-guest: Allocate request data dynamically Commit ae596615d93d ("virt: sev-guest: Reduce the scope of SNP command mutex") narrowed the command mutex scope to snp_send_guest_request(). However, GET_REPORT, GET_DERIVED_KEY, and GET_EXT_REPORT share the req structure in snp_guest_dev. Without the mutex protection, concurrent requests can overwrite each other's data. Fix it by dynamically allocating the request structure. Fixes: ae596615d93d ("virt: sev-guest: Reduce the scope of SNP command mutex") Closes: https://github.com/AMDESE/AMDSEV/issues/265 Reported-by: andreas.stuehrk@yaxi.tech Signed-off-by: Nikunj A Dadhania Signed-off-by: Alexey Kardashevskiy Signed-off-by: Borislav Petkov (AMD) Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250307013700.437505-2-aik@amd.com --- drivers/virt/coco/sev-guest/sev-guest.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index 264b6523fe52..23ac177472be 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -38,12 +38,6 @@ struct snp_guest_dev { struct miscdevice misc; struct snp_msg_desc *msg_desc; - - union { - struct snp_report_req report; - struct snp_derived_key_req derived_key; - struct snp_ext_report_req ext_report; - } req; }; /* @@ -71,7 +65,7 @@ struct snp_req_resp { static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { - struct snp_report_req *report_req = &snp_dev->req.report; + struct snp_report_req *report_req __free(kfree) = NULL; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_report_resp *report_resp; struct snp_guest_req req = {}; @@ -80,6 +74,10 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io if (!arg->req_data || !arg->resp_data) return -EINVAL; + report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT); + if (!report_req) + return -ENOMEM; + if (copy_from_user(report_req, (void __user *)arg->req_data, sizeof(*report_req))) return -EFAULT; @@ -116,7 +114,7 @@ e_free: static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { - struct snp_derived_key_req *derived_key_req = &snp_dev->req.derived_key; + struct snp_derived_key_req *derived_key_req __free(kfree) = NULL; struct snp_derived_key_resp derived_key_resp = {0}; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_guest_req req = {}; @@ -136,6 +134,10 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque if (sizeof(buf) < resp_len) return -ENOMEM; + derived_key_req = kzalloc(sizeof(*derived_key_req), GFP_KERNEL_ACCOUNT); + if (!derived_key_req) + return -ENOMEM; + if (copy_from_user(derived_key_req, (void __user *)arg->req_data, sizeof(*derived_key_req))) return -EFAULT; @@ -168,7 +170,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques struct snp_req_resp *io) { - struct snp_ext_report_req *report_req = &snp_dev->req.ext_report; + struct snp_ext_report_req *report_req __free(kfree) = NULL; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_report_resp *report_resp; struct snp_guest_req req = {}; @@ -178,6 +180,10 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques if (sockptr_is_null(io->req_data) || sockptr_is_null(io->resp_data)) return -EINVAL; + report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT); + if (!report_req) + return -ENOMEM; + if (copy_from_sockptr(report_req, io->req_data, sizeof(*report_req))) return -EFAULT; -- cgit v1.2.3 From 3e385c0d6ce88ac9916dcf84267bd5855d830748 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Fri, 7 Mar 2025 12:37:00 +1100 Subject: virt: sev-guest: Move SNP Guest Request data pages handling under snp_cmd_mutex Compared to the SNP Guest Request, the "Extended" version adds data pages for receiving certificates. If not enough pages provided, the HV can report to the VM how much is needed so the VM can reallocate and repeat. Commit ae596615d93d ("virt: sev-guest: Reduce the scope of SNP command mutex") moved handling of the allocated/desired pages number out of scope of said mutex and create a possibility for a race (multiple instances trying to trigger Extended request in a VM) as there is just one instance of snp_msg_desc per /dev/sev-guest and no locking other than snp_cmd_mutex. Fix the issue by moving the data blob/size and the GHCB input struct (snp_req_data) into snp_guest_req which is allocated on stack now and accessed by the GHCB caller under that mutex. Stop allocating SEV_FW_BLOB_MAX_SIZE in snp_msg_alloc() as only one of four callers needs it. Free the received blob in get_ext_report() right after it is copied to the userspace. Possible future users of snp_send_guest_request() are likely to have different ideas about the buffer size anyways. Fixes: ae596615d93d ("virt: sev-guest: Reduce the scope of SNP command mutex") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nikunj A Dadhania Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250307013700.437505-3-aik@amd.com --- arch/x86/coco/sev/core.c | 23 ++++++++-------------- arch/x86/include/asm/sev.h | 6 +++--- drivers/virt/coco/sev-guest/sev-guest.c | 34 +++++++++++++++++++++++++++------ 3 files changed, 39 insertions(+), 24 deletions(-) diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c index 82492efc5d94..96c7bc698e6b 100644 --- a/arch/x86/coco/sev/core.c +++ b/arch/x86/coco/sev/core.c @@ -2853,19 +2853,8 @@ struct snp_msg_desc *snp_msg_alloc(void) if (!mdesc->response) goto e_free_request; - mdesc->certs_data = alloc_shared_pages(SEV_FW_BLOB_MAX_SIZE); - if (!mdesc->certs_data) - goto e_free_response; - - /* initial the input address for guest request */ - mdesc->input.req_gpa = __pa(mdesc->request); - mdesc->input.resp_gpa = __pa(mdesc->response); - mdesc->input.data_gpa = __pa(mdesc->certs_data); - return mdesc; -e_free_response: - free_shared_pages(mdesc->response, sizeof(struct snp_guest_msg)); e_free_request: free_shared_pages(mdesc->request, sizeof(struct snp_guest_msg)); e_unmap: @@ -2885,7 +2874,6 @@ void snp_msg_free(struct snp_msg_desc *mdesc) kfree(mdesc->ctx); free_shared_pages(mdesc->response, sizeof(struct snp_guest_msg)); free_shared_pages(mdesc->request, sizeof(struct snp_guest_msg)); - free_shared_pages(mdesc->certs_data, SEV_FW_BLOB_MAX_SIZE); iounmap((__force void __iomem *)mdesc->secrets); memset(mdesc, 0, sizeof(*mdesc)); @@ -3054,7 +3042,7 @@ retry_request: * sequence number must be incremented or the VMPCK must be deleted to * prevent reuse of the IV. */ - rc = snp_issue_guest_request(req, &mdesc->input, rio); + rc = snp_issue_guest_request(req, &req->input, rio); switch (rc) { case -ENOSPC: /* @@ -3064,7 +3052,7 @@ retry_request: * order to increment the sequence number and thus avoid * IV reuse. */ - override_npages = mdesc->input.data_npages; + override_npages = req->input.data_npages; req->exit_code = SVM_VMGEXIT_GUEST_REQUEST; /* @@ -3120,7 +3108,7 @@ retry_request: } if (override_npages) - mdesc->input.data_npages = override_npages; + req->input.data_npages = override_npages; return rc; } @@ -3158,6 +3146,11 @@ int snp_send_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_req *req */ memcpy(mdesc->request, &mdesc->secret_request, sizeof(mdesc->secret_request)); + /* Initialize the input address for guest request */ + req->input.req_gpa = __pa(mdesc->request); + req->input.resp_gpa = __pa(mdesc->response); + req->input.data_gpa = req->certs_data ? __pa(req->certs_data) : 0; + rc = __handle_guest_request(mdesc, req, rio); if (rc) { if (rc == -EIO && diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index 1581246491b5..ba7999f66abe 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -203,6 +203,9 @@ struct snp_guest_req { unsigned int vmpck_id; u8 msg_version; u8 msg_type; + + struct snp_req_data input; + void *certs_data; }; /* @@ -263,9 +266,6 @@ struct snp_msg_desc { struct snp_guest_msg secret_request, secret_response; struct snp_secrets_page *secrets; - struct snp_req_data input; - - void *certs_data; struct aesgcm_ctx *ctx; diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index 23ac177472be..70fbc9a3e703 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -176,6 +176,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques struct snp_guest_req req = {}; int ret, npages = 0, resp_len; sockptr_t certs_address; + struct page *page; if (sockptr_is_null(io->req_data) || sockptr_is_null(io->resp_data)) return -EINVAL; @@ -209,8 +210,20 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques * the host. If host does not supply any certs in it, then copy * zeros to indicate that certificate data was not provided. */ - memset(mdesc->certs_data, 0, report_req->certs_len); npages = report_req->certs_len >> PAGE_SHIFT; + page = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, + get_order(report_req->certs_len)); + if (!page) + return -ENOMEM; + + req.certs_data = page_address(page); + ret = set_memory_decrypted((unsigned long)req.certs_data, npages); + if (ret) { + pr_err("failed to mark page shared, ret=%d\n", ret); + __free_pages(page, get_order(report_req->certs_len)); + return -EFAULT; + } + cmd: /* * The intermediate response buffer is used while decrypting the @@ -219,10 +232,12 @@ cmd: */ resp_len = sizeof(report_resp->data) + mdesc->ctx->authsize; report_resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); - if (!report_resp) - return -ENOMEM; + if (!report_resp) { + ret = -ENOMEM; + goto e_free_data; + } - mdesc->input.data_npages = npages; + req.input.data_npages = npages; req.msg_version = arg->msg_version; req.msg_type = SNP_MSG_REPORT_REQ; @@ -237,7 +252,7 @@ cmd: /* If certs length is invalid then copy the returned length */ if (arg->vmm_error == SNP_GUEST_VMM_ERR_INVALID_LEN) { - report_req->certs_len = mdesc->input.data_npages << PAGE_SHIFT; + report_req->certs_len = req.input.data_npages << PAGE_SHIFT; if (copy_to_sockptr(io->req_data, report_req, sizeof(*report_req))) ret = -EFAULT; @@ -246,7 +261,7 @@ cmd: if (ret) goto e_free; - if (npages && copy_to_sockptr(certs_address, mdesc->certs_data, report_req->certs_len)) { + if (npages && copy_to_sockptr(certs_address, req.certs_data, report_req->certs_len)) { ret = -EFAULT; goto e_free; } @@ -256,6 +271,13 @@ cmd: e_free: kfree(report_resp); +e_free_data: + if (npages) { + if (set_memory_encrypted((unsigned long)req.certs_data, npages)) + WARN_ONCE(ret, "failed to restore encryption mask (leak it)\n"); + else + __free_pages(page, get_order(report_req->certs_len)); + } return ret; } -- cgit v1.2.3 From 6914f7e2e25fac9d1d2b62c208eaa5f2bf810fe9 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 6 Mar 2025 23:00:16 +0100 Subject: x86/mm: Define PTRS_PER_PMD for assembly code too Andy reported the following build warning from head_32.S: In file included from arch/x86/kernel/head_32.S:29: arch/x86/include/asm/pgtable_32.h:59:5: error: "PTRS_PER_PMD" is not defined, evaluates to 0 [-Werror=undef] 59 | #if PTRS_PER_PMD > 1 The reason is that on 2-level i386 paging the folded in PMD's PTRS_PER_PMD constant is not defined in assembly headers, only in generic MM C headers. Instead of trying to fish out the definition from the generic headers, just define it - it even has a comment for it already... Reported-by: Andy Shevchenko Tested-by: Andy Shevchenko Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/Z8oa8AUVyi2HWfo9@gmail.com --- arch/x86/include/asm/pgtable-2level_types.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/pgtable-2level_types.h b/arch/x86/include/asm/pgtable-2level_types.h index 7f6ccff0ba72..4a12c276b181 100644 --- a/arch/x86/include/asm/pgtable-2level_types.h +++ b/arch/x86/include/asm/pgtable-2level_types.h @@ -23,17 +23,17 @@ typedef union { #define ARCH_PAGE_TABLE_SYNC_MASK PGTBL_PMD_MODIFIED /* - * traditional i386 two-level paging structure: + * Traditional i386 two-level paging structure: */ #define PGDIR_SHIFT 22 #define PTRS_PER_PGD 1024 - /* - * the i386 is two-level, so we don't really have any - * PMD directory physically. + * The i386 is two-level, so we don't really have any + * PMD directory physically: */ +#define PTRS_PER_PMD 1 #define PTRS_PER_PTE 1024 -- cgit v1.2.3 From 058a6bec37c6c3b826158f6d26b75de43816a880 Mon Sep 17 00:00:00 2001 From: "Borislav Petkov (AMD)" Date: Fri, 7 Mar 2025 23:02:56 +0100 Subject: x86/microcode/AMD: Add some forgotten models to the SHA check MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add some more forgotten models to the SHA check. Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Reported-by: Toralf Förster Signed-off-by: Borislav Petkov (AMD) Signed-off-by: Ingo Molnar Tested-by: Toralf Förster Link: https://lore.kernel.org/r/20250307220256.11816-1-bp@kernel.org --- arch/x86/kernel/cpu/microcode/amd.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 95ac1c6a84fb..c69b1bc45483 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -175,23 +175,29 @@ static bool need_sha_check(u32 cur_rev) { switch (cur_rev >> 8) { case 0x80012: return cur_rev <= 0x800126f; break; + case 0x80082: return cur_rev <= 0x800820f; break; case 0x83010: return cur_rev <= 0x830107c; break; case 0x86001: return cur_rev <= 0x860010e; break; case 0x86081: return cur_rev <= 0x8608108; break; case 0x87010: return cur_rev <= 0x8701034; break; case 0x8a000: return cur_rev <= 0x8a0000a; break; + case 0xa0010: return cur_rev <= 0xa00107a; break; case 0xa0011: return cur_rev <= 0xa0011da; break; case 0xa0012: return cur_rev <= 0xa001243; break; + case 0xa0082: return cur_rev <= 0xa00820e; break; case 0xa1011: return cur_rev <= 0xa101153; break; case 0xa1012: return cur_rev <= 0xa10124e; break; case 0xa1081: return cur_rev <= 0xa108109; break; case 0xa2010: return cur_rev <= 0xa20102f; break; case 0xa2012: return cur_rev <= 0xa201212; break; + case 0xa4041: return cur_rev <= 0xa404109; break; + case 0xa5000: return cur_rev <= 0xa500013; break; case 0xa6012: return cur_rev <= 0xa60120a; break; case 0xa7041: return cur_rev <= 0xa704109; break; case 0xa7052: return cur_rev <= 0xa705208; break; case 0xa7080: return cur_rev <= 0xa708009; break; case 0xa70c0: return cur_rev <= 0xa70C009; break; + case 0xaa001: return cur_rev <= 0xaa00116; break; case 0xaa002: return cur_rev <= 0xaa00218; break; default: break; } -- cgit v1.2.3