From 48cff270b037022e37835d93361646205ca25101 Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Wed, 10 Mar 2021 17:19:14 -0500 Subject: tpm: efi: Use local variable for calculating final log size When tpm_read_log_efi is called multiple times, which happens when one loads and unloads a TPM2 driver multiple times, then the global variable efi_tpm_final_log_size will at some point become a negative number due to the subtraction of final_events_preboot_size occurring each time. Use a local variable to avoid this integer underflow. The following issue is now resolved: Mar 8 15:35:12 hibinst kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Mar 8 15:35:12 hibinst kernel: Workqueue: tpm-vtpm vtpm_proxy_work [tpm_vtpm_proxy] Mar 8 15:35:12 hibinst kernel: RIP: 0010:__memcpy+0x12/0x20 Mar 8 15:35:12 hibinst kernel: Code: 00 b8 01 00 00 00 85 d2 74 0a c7 05 44 7b ef 00 0f 00 00 00 c3 cc cc cc 66 66 90 66 90 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 f3 a4 Mar 8 15:35:12 hibinst kernel: RSP: 0018:ffff9ac4c0fcfde0 EFLAGS: 00010206 Mar 8 15:35:12 hibinst kernel: RAX: ffff88f878cefed5 RBX: ffff88f878ce9000 RCX: 1ffffffffffffe0f Mar 8 15:35:12 hibinst kernel: RDX: 0000000000000003 RSI: ffff9ac4c003bff9 RDI: ffff88f878cf0e4d Mar 8 15:35:12 hibinst kernel: RBP: ffff9ac4c003b000 R08: 0000000000001000 R09: 000000007e9d6073 Mar 8 15:35:12 hibinst kernel: R10: ffff9ac4c003b000 R11: ffff88f879ad3500 R12: 0000000000000ed5 Mar 8 15:35:12 hibinst kernel: R13: ffff88f878ce9760 R14: 0000000000000002 R15: ffff88f77de7f018 Mar 8 15:35:12 hibinst kernel: FS: 0000000000000000(0000) GS:ffff88f87bd00000(0000) knlGS:0000000000000000 Mar 8 15:35:12 hibinst kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Mar 8 15:35:12 hibinst kernel: CR2: ffff9ac4c003c000 CR3: 00000001785a6004 CR4: 0000000000060ee0 Mar 8 15:35:12 hibinst kernel: Call Trace: Mar 8 15:35:12 hibinst kernel: tpm_read_log_efi+0x152/0x1a7 Mar 8 15:35:12 hibinst kernel: tpm_bios_log_setup+0xc8/0x1c0 Mar 8 15:35:12 hibinst kernel: tpm_chip_register+0x8f/0x260 Mar 8 15:35:12 hibinst kernel: vtpm_proxy_work+0x16/0x60 [tpm_vtpm_proxy] Mar 8 15:35:12 hibinst kernel: process_one_work+0x1b4/0x370 Mar 8 15:35:12 hibinst kernel: worker_thread+0x53/0x3e0 Mar 8 15:35:12 hibinst kernel: ? process_one_work+0x370/0x370 Cc: stable@vger.kernel.org Fixes: 166a2809d65b ("tpm: Don't duplicate events from the final event log in the TCG2 log") Signed-off-by: Stefan Berger Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/eventlog/efi.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) (limited to 'drivers') diff --git a/drivers/char/tpm/eventlog/efi.c b/drivers/char/tpm/eventlog/efi.c index 35229e5143ca..e6cb9d525e30 100644 --- a/drivers/char/tpm/eventlog/efi.c +++ b/drivers/char/tpm/eventlog/efi.c @@ -17,6 +17,7 @@ int tpm_read_log_efi(struct tpm_chip *chip) { struct efi_tcg2_final_events_table *final_tbl = NULL; + int final_events_log_size = efi_tpm_final_log_size; struct linux_efi_tpm_eventlog *log_tbl; struct tpm_bios_log *log; u32 log_size; @@ -66,12 +67,12 @@ int tpm_read_log_efi(struct tpm_chip *chip) ret = tpm_log_version; if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR || - efi_tpm_final_log_size == 0 || + final_events_log_size == 0 || tpm_log_version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) goto out; final_tbl = memremap(efi.tpm_final_log, - sizeof(*final_tbl) + efi_tpm_final_log_size, + sizeof(*final_tbl) + final_events_log_size, MEMREMAP_WB); if (!final_tbl) { pr_err("Could not map UEFI TPM final log\n"); @@ -80,10 +81,18 @@ int tpm_read_log_efi(struct tpm_chip *chip) goto out; } - efi_tpm_final_log_size -= log_tbl->final_events_preboot_size; + /* + * The 'final events log' size excludes the 'final events preboot log' + * at its beginning. + */ + final_events_log_size -= log_tbl->final_events_preboot_size; + /* + * Allocate memory for the 'combined log' where we will append the + * 'final events log' to. + */ tmp = krealloc(log->bios_event_log, - log_size + efi_tpm_final_log_size, + log_size + final_events_log_size, GFP_KERNEL); if (!tmp) { kfree(log->bios_event_log); @@ -94,15 +103,19 @@ int tpm_read_log_efi(struct tpm_chip *chip) log->bios_event_log = tmp; /* - * Copy any of the final events log that didn't also end up in the - * main log. Events can be logged in both if events are generated + * Append any of the 'final events log' that didn't also end up in the + * 'main log'. Events can be logged in both if events are generated * between GetEventLog() and ExitBootServices(). */ memcpy((void *)log->bios_event_log + log_size, final_tbl->events + log_tbl->final_events_preboot_size, - efi_tpm_final_log_size); + final_events_log_size); + /* + * The size of the 'combined log' is the size of the 'main log' plus + * the size of the 'final events log'. + */ log->bios_event_log_end = log->bios_event_log + - log_size + efi_tpm_final_log_size; + log_size + final_events_log_size; out: memunmap(final_tbl); -- cgit v1.2.3 From 3dcd15665aca80197333500a4be3900948afccc1 Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Wed, 10 Mar 2021 17:19:15 -0500 Subject: tpm: acpi: Check eventlog signature before using it Check the eventlog signature before using it. This avoids using an empty log, as may be the case when QEMU created the ACPI tables, rather than probing the EFI log next. This resolves an issue where the EFI log was empty since an empty ACPI log was used. Cc: stable@vger.kernel.org Fixes: 85467f63a05c ("tpm: Add support for event log pointer found in TPM2 ACPI table") Signed-off-by: Stefan Berger Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/eventlog/acpi.c | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c index 3633ed70f48f..1b18ce5ebab1 100644 --- a/drivers/char/tpm/eventlog/acpi.c +++ b/drivers/char/tpm/eventlog/acpi.c @@ -41,6 +41,27 @@ struct acpi_tcpa { }; }; +/* Check that the given log is indeed a TPM2 log. */ +static bool tpm_is_tpm2_log(void *bios_event_log, u64 len) +{ + struct tcg_efi_specid_event_head *efispecid; + struct tcg_pcr_event *event_header; + int n; + + if (len < sizeof(*event_header)) + return false; + len -= sizeof(*event_header); + event_header = bios_event_log; + + if (len < sizeof(*efispecid)) + return false; + efispecid = (struct tcg_efi_specid_event_head *)event_header->event; + + n = memcmp(efispecid->signature, TCG_SPECID_SIG, + sizeof(TCG_SPECID_SIG)); + return n == 0; +} + /* read binary bios log */ int tpm_read_log_acpi(struct tpm_chip *chip) { @@ -52,6 +73,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip) struct acpi_table_tpm2 *tbl; struct acpi_tpm2_phy *tpm2_phy; int format; + int ret; log = &chip->log; @@ -112,6 +134,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip) log->bios_event_log_end = log->bios_event_log + len; + ret = -EIO; virt = acpi_os_map_iomem(start, len); if (!virt) goto err; @@ -119,11 +142,19 @@ int tpm_read_log_acpi(struct tpm_chip *chip) memcpy_fromio(log->bios_event_log, virt, len); acpi_os_unmap_iomem(virt, len); + + if (chip->flags & TPM_CHIP_FLAG_TPM2 && + !tpm_is_tpm2_log(log->bios_event_log, len)) { + /* try EFI log next */ + ret = -ENODEV; + goto err; + } + return format; err: kfree(log->bios_event_log); log->bios_event_log = NULL; - return -EIO; + return ret; } -- cgit v1.2.3 From 9716ac65efc8f780549b03bddf41e60c445d4709 Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Wed, 10 Mar 2021 17:19:16 -0500 Subject: tpm: vtpm_proxy: Avoid reading host log when using a virtual device Avoid allocating memory and reading the host log when a virtual device is used since this log is of no use to that driver. A virtual device can be identified through the flag TPM_CHIP_FLAG_VIRTUAL, which is only set for the tpm_vtpm_proxy driver. Cc: stable@vger.kernel.org Fixes: 6f99612e2500 ("tpm: Proxy driver for supporting multiple emulated TPMs") Signed-off-by: Stefan Berger Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/eventlog/common.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers') diff --git a/drivers/char/tpm/eventlog/common.c b/drivers/char/tpm/eventlog/common.c index 7460f230bae4..8512ec76d526 100644 --- a/drivers/char/tpm/eventlog/common.c +++ b/drivers/char/tpm/eventlog/common.c @@ -107,6 +107,9 @@ void tpm_bios_log_setup(struct tpm_chip *chip) int log_version; int rc = 0; + if (chip->flags & TPM_CHIP_FLAG_VIRTUAL) + return; + rc = tpm_read_log(chip); if (rc < 0) return; -- cgit v1.2.3 From 3d785d73b4c1014839d9f9af0ee526f8d5706a73 Mon Sep 17 00:00:00 2001 From: Zhihao Cheng Date: Fri, 9 Apr 2021 09:12:01 +0800 Subject: char: tpm: fix error return code in tpm_cr50_i2c_tis_recv() Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Fixes: 3a253caaad11 ("char: tpm: add i2c driver for cr50") Reported-by: Hulk Robot Signed-off-by: Zhihao Cheng Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_tis_i2c_cr50.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/char/tpm/tpm_tis_i2c_cr50.c b/drivers/char/tpm/tpm_tis_i2c_cr50.c index ec9a65e7887d..f19c227d20f4 100644 --- a/drivers/char/tpm/tpm_tis_i2c_cr50.c +++ b/drivers/char/tpm/tpm_tis_i2c_cr50.c @@ -483,6 +483,7 @@ static int tpm_cr50_i2c_tis_recv(struct tpm_chip *chip, u8 *buf, size_t buf_len) expected = be32_to_cpup((__be32 *)(buf + 2)); if (expected > buf_len) { dev_err(&chip->dev, "Buffer too small to receive i2c data\n"); + rc = -E2BIG; goto out_err; } -- cgit v1.2.3