Re: [PATCH v3] tpm: only set efi_tpm_final_log_size after successful event log parsing
On Wed, Sep 25, 2019 at 10:27:05AM -0700, Jerry Snitselaar wrote: > If __calc_tpm2_event_size fails to parse an event it will return 0, > resulting tpm2_calc_event_log_size returning -1. Currently there is > no check of this return value, and efi_tpm_final_log_size can end up > being set to this negative value resulting in a panic like the > the one given below. > > Also __calc_tpm2_event_size returns a size of 0 when it fails > to parse an event, so update function documentation to reflect this. > > [0.774340] BUG: unable to handle page fault for address: bc8fc00866ad > [0.774788] #PF: supervisor read access in kernel mode > [0.774788] #PF: error_code(0x) - not-present page > [0.774788] PGD 107d36067 P4D 107d36067 PUD 107d37067 PMD 107d38067 PTE 0 > [0.774788] Oops: [#1] SMP PTI > [0.774788] CPU: 0 PID: 1 Comm: swapper/0 Not tainted > 5.3.0-0.rc2.1.elrdy.x86_64 #1 > [0.774788] Hardware name: LENOVO 20HGS22D0W/20HGS22D0W, BIOS N1WET51W > (1.30 ) 09/14/2018 > [0.774788] RIP: 0010:memcpy_erms+0x6/0x10 > [0.774788] Code: 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 > 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 a4 > c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe > [0.774788] RSP: :bc8fc0073b30 EFLAGS: 00010286 > [0.774788] RAX: 9b1fc7c5b367 RBX: 9b1fc839 RCX: > e962 > [0.774788] RDX: e962 RSI: bc8fc00866ad RDI: > 9b1fc7c5b367 > [0.774788] RBP: 9b1c10ca7018 R08: bc8fc0085fff R09: > 8063 > [0.774788] R10: 1000 R11: 000fffe0 R12: > 3367 > [0.774788] R13: 9b1fcc47c010 R14: bc8fc0085000 R15: > 0002 > [0.774788] FS: () GS:9b1fce20() > knlGS: > [0.774788] CS: 0010 DS: ES: CR0: 80050033 > [0.774788] CR2: bc8fc00866ad CR3: 00029f60a001 CR4: > 003606f0 > [0.774788] DR0: DR1: DR2: > > [0.774788] DR3: DR6: fffe0ff0 DR7: > 0400 > [0.774788] Call Trace: > [0.774788] tpm_read_log_efi+0x156/0x1a0 > [0.774788] tpm_bios_log_setup+0xc8/0x190 > [0.774788] tpm_chip_register+0x50/0x1c0 > [0.774788] tpm_tis_core_init.cold.9+0x28c/0x466 > [0.774788] tpm_tis_plat_probe+0xcc/0xea > [0.774788] platform_drv_probe+0x35/0x80 > [0.774788] really_probe+0xef/0x390 > [0.774788] driver_probe_device+0xb4/0x100 > [0.774788] device_driver_attach+0x4f/0x60 > [0.774788] __driver_attach+0x86/0x140 > [0.774788] ? device_driver_attach+0x60/0x60 > [0.774788] bus_for_each_dev+0x76/0xc0 > [0.774788] ? klist_add_tail+0x3b/0x70 > [0.774788] bus_add_driver+0x14a/0x1e0 > [0.774788] ? tpm_init+0xea/0xea > [0.774788] ? do_early_param+0x8e/0x8e > [0.774788] driver_register+0x6b/0xb0 > [0.774788] ? tpm_init+0xea/0xea > [0.774788] init_tis+0x86/0xd8 > [0.774788] ? do_early_param+0x8e/0x8e > [0.774788] ? driver_register+0x94/0xb0 > [0.774788] do_one_initcall+0x46/0x1e4 > [0.774788] ? do_early_param+0x8e/0x8e > [0.774788] kernel_init_freeable+0x199/0x242 > [0.774788] ? rest_init+0xaa/0xaa > [0.774788] kernel_init+0xa/0x106 > [0.774788] ret_from_fork+0x35/0x40 > [0.774788] Modules linked in: > [0.774788] CR2: bc8fc00866ad > [0.774788] ---[ end trace 42930799f8d6eaea ]--- > [0.774788] RIP: 0010:memcpy_erms+0x6/0x10 > [0.774788] Code: 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 > 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 a4 > c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe > [0.774788] RSP: :bc8fc0073b30 EFLAGS: 00010286 > [0.774788] RAX: 9b1fc7c5b367 RBX: 9b1fc839 RCX: > e962 > [0.774788] RDX: e962 RSI: bc8fc00866ad RDI: > 9b1fc7c5b367 > [0.774788] RBP: 9b1c10ca7018 R08: bc8fc0085fff R09: > 8063 > [0.774788] R10: 1000 R11: 000fffe0 R12: > 3367 > [0.774788] R13: 9b1fcc47c010 R14: bc8fc0085000 R15: > 0002 > [0.774788] FS: () GS:9b1fce20() > knlGS: > [0.774788] CS: 0010 DS: ES: CR0: 80050033 > [0.774788] CR2: bc8fc00866ad CR3: 00029f60a001 CR4: > 003606f0 > [0.774788] DR0: DR1: DR2: > > [0.774788] DR3: DR6: fffe0ff0 DR7: > 0400 > [0.774788] Kernel panic - not syncing: Fatal exception > [0.774788] Kernel Offset: 0x1d00 from 0x8100 (relocation > range: 0x8000-0xbfff) > [0.774788] ---[ end Kernel panic - not syncing:
Re: [PATCH v3] tpm: only set efi_tpm_final_log_size after successful event log parsing
On Wed, 25 Sep 2019 at 19:27, Jerry Snitselaar wrote:
>
> If __calc_tpm2_event_size fails to parse an event it will return 0,
> resulting tpm2_calc_event_log_size returning -1. Currently there is
> no check of this return value, and efi_tpm_final_log_size can end up
> being set to this negative value resulting in a panic like the
> the one given below.
>
> Also __calc_tpm2_event_size returns a size of 0 when it fails
> to parse an event, so update function documentation to reflect this.
>
...
>
> The root cause of the issue that caused the failure of event parsing
> in this case is resolved by Peter Jone's patchset dealing with large
> event logs where crossing over a page boundary causes the page with
> the event count to be unmapped.
>
> Fixes: c46f3405692de ("tpm: Reserve the TPM final events table")
> Cc: linux-efi@vger.kernel.org
> Cc: linux-integr...@vger.kernel.org
> Cc: sta...@vger.kernel.org
> Cc: Matthew Garrett
> Cc: Ard Biesheuvel
> Cc: Jarkko Sakkinen
> Signed-off-by: Jerry Snitselaar
Thanks Jerry, I have queued this in the efi/urgent branch.
> ---
> v3: rebase on top of Peter Jone's patchset
> v2: added FW_BUG to pr_err, and renamed label to out_calc.
> Updated doc comment for __calc_tpm2_event_size.
>
> drivers/firmware/efi/tpm.c | 9 -
> include/linux/tpm_eventlog.h | 2 +-
> 2 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
> index b9ae5c6f9b9c..703469c1ab8e 100644
> --- a/drivers/firmware/efi/tpm.c
> +++ b/drivers/firmware/efi/tpm.c
> @@ -85,11 +85,18 @@ int __init efi_tpm_eventlog_init(void)
> final_tbl->nr_events,
> log_tbl->log);
> }
> +
> + if (tbl_size < 0) {
> + pr_err(FW_BUG "Failed to parse event in TPM Final Events
> Log\n");
> + goto out_calc;
> + }
> +
> memblock_reserve((unsigned long)final_tbl,
> tbl_size + sizeof(*final_tbl));
> - early_memunmap(final_tbl, sizeof(*final_tbl));
> efi_tpm_final_log_size = tbl_size;
>
> +out_calc:
> + early_memunmap(final_tbl, sizeof(*final_tbl));
> out:
> early_memunmap(log_tbl, sizeof(*log_tbl));
> return ret;
> diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h
> index 12584b69a3f3..2dfdd63ac034 100644
> --- a/include/linux/tpm_eventlog.h
> +++ b/include/linux/tpm_eventlog.h
> @@ -152,7 +152,7 @@ struct tcg_algorithm_info {
> * total. Once we've done this we know the offset of the data length field,
> * and can calculate the total size of the event.
> *
> - * Return: size of the event on success, <0 on failure
> + * Return: size of the event on success, 0 on failure
> */
>
> static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
> --
> 2.23.0
>
[PATCH v3] tpm: only set efi_tpm_final_log_size after successful event log parsing
If __calc_tpm2_event_size fails to parse an event it will return 0, resulting tpm2_calc_event_log_size returning -1. Currently there is no check of this return value, and efi_tpm_final_log_size can end up being set to this negative value resulting in a panic like the the one given below. Also __calc_tpm2_event_size returns a size of 0 when it fails to parse an event, so update function documentation to reflect this. [0.774340] BUG: unable to handle page fault for address: bc8fc00866ad [0.774788] #PF: supervisor read access in kernel mode [0.774788] #PF: error_code(0x) - not-present page [0.774788] PGD 107d36067 P4D 107d36067 PUD 107d37067 PMD 107d38067 PTE 0 [0.774788] Oops: [#1] SMP PTI [0.774788] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.3.0-0.rc2.1.elrdy.x86_64 #1 [0.774788] Hardware name: LENOVO 20HGS22D0W/20HGS22D0W, BIOS N1WET51W (1.30 ) 09/14/2018 [0.774788] RIP: 0010:memcpy_erms+0x6/0x10 [0.774788] Code: 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe [0.774788] RSP: :bc8fc0073b30 EFLAGS: 00010286 [0.774788] RAX: 9b1fc7c5b367 RBX: 9b1fc839 RCX: e962 [0.774788] RDX: e962 RSI: bc8fc00866ad RDI: 9b1fc7c5b367 [0.774788] RBP: 9b1c10ca7018 R08: bc8fc0085fff R09: 8063 [0.774788] R10: 1000 R11: 000fffe0 R12: 3367 [0.774788] R13: 9b1fcc47c010 R14: bc8fc0085000 R15: 0002 [0.774788] FS: () GS:9b1fce20() knlGS: [0.774788] CS: 0010 DS: ES: CR0: 80050033 [0.774788] CR2: bc8fc00866ad CR3: 00029f60a001 CR4: 003606f0 [0.774788] DR0: DR1: DR2: [0.774788] DR3: DR6: fffe0ff0 DR7: 0400 [0.774788] Call Trace: [0.774788] tpm_read_log_efi+0x156/0x1a0 [0.774788] tpm_bios_log_setup+0xc8/0x190 [0.774788] tpm_chip_register+0x50/0x1c0 [0.774788] tpm_tis_core_init.cold.9+0x28c/0x466 [0.774788] tpm_tis_plat_probe+0xcc/0xea [0.774788] platform_drv_probe+0x35/0x80 [0.774788] really_probe+0xef/0x390 [0.774788] driver_probe_device+0xb4/0x100 [0.774788] device_driver_attach+0x4f/0x60 [0.774788] __driver_attach+0x86/0x140 [0.774788] ? device_driver_attach+0x60/0x60 [0.774788] bus_for_each_dev+0x76/0xc0 [0.774788] ? klist_add_tail+0x3b/0x70 [0.774788] bus_add_driver+0x14a/0x1e0 [0.774788] ? tpm_init+0xea/0xea [0.774788] ? do_early_param+0x8e/0x8e [0.774788] driver_register+0x6b/0xb0 [0.774788] ? tpm_init+0xea/0xea [0.774788] init_tis+0x86/0xd8 [0.774788] ? do_early_param+0x8e/0x8e [0.774788] ? driver_register+0x94/0xb0 [0.774788] do_one_initcall+0x46/0x1e4 [0.774788] ? do_early_param+0x8e/0x8e [0.774788] kernel_init_freeable+0x199/0x242 [0.774788] ? rest_init+0xaa/0xaa [0.774788] kernel_init+0xa/0x106 [0.774788] ret_from_fork+0x35/0x40 [0.774788] Modules linked in: [0.774788] CR2: bc8fc00866ad [0.774788] ---[ end trace 42930799f8d6eaea ]--- [0.774788] RIP: 0010:memcpy_erms+0x6/0x10 [0.774788] Code: 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe [0.774788] RSP: :bc8fc0073b30 EFLAGS: 00010286 [0.774788] RAX: 9b1fc7c5b367 RBX: 9b1fc839 RCX: e962 [0.774788] RDX: e962 RSI: bc8fc00866ad RDI: 9b1fc7c5b367 [0.774788] RBP: 9b1c10ca7018 R08: bc8fc0085fff R09: 8063 [0.774788] R10: 1000 R11: 000fffe0 R12: 3367 [0.774788] R13: 9b1fcc47c010 R14: bc8fc0085000 R15: 0002 [0.774788] FS: () GS:9b1fce20() knlGS: [0.774788] CS: 0010 DS: ES: CR0: 80050033 [0.774788] CR2: bc8fc00866ad CR3: 00029f60a001 CR4: 003606f0 [0.774788] DR0: DR1: DR2: [0.774788] DR3: DR6: fffe0ff0 DR7: 0400 [0.774788] Kernel panic - not syncing: Fatal exception [0.774788] Kernel Offset: 0x1d00 from 0x8100 (relocation range: 0x8000-0xbfff) [0.774788] ---[ end Kernel panic - not syncing: Fatal exception ]--- The root cause of the issue that caused the failure of event parsing in this case is resolved by Peter Jone's patchset dealing with large event logs where crossing over a page boundary causes the page with the event count to be unmapped. Fixes: c46f3405692de
