From: David Howells <dhowells@redhat.com> To: linux-kernel@vger.kernel.org Cc: matthew.garrett@nebula.com, linux-efi@vger.kernel.org, gnomes@lxorguk.ukuu.org.uk, gregkh@linuxfoundation.org, dhowells@redhat.com, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org Subject: [PATCH 15/24] asus-wmi: Restrict debugfs interface when the kernel is locked down Date: Wed, 05 Apr 2017 18:12:12 +0100 [thread overview] Message-ID: <149141233199.31282.4267532443918292855.stgit@warthog.procyon.org.uk> (raw) In-Reply-To: <149141219387.31282.6648284836568938717.stgit@warthog.procyon.org.uk> From: Matthew Garrett <matthew.garrett@nebula.com> We have no way of validating what all of the Asus WMI methods do on a given machine - and there's a risk that some will allow hardware state to be manipulated in such a way that arbitrary code can be executed in the kernel, circumventing module loading restrictions. Prevent that if the kernel is locked down. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: David Howells <dhowells@redhat.com> --- drivers/platform/x86/asus-wmi.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c index 8fe5890bf539..feef25076813 100644 --- a/drivers/platform/x86/asus-wmi.c +++ b/drivers/platform/x86/asus-wmi.c @@ -1900,6 +1900,9 @@ static int show_dsts(struct seq_file *m, void *data) int err; u32 retval = -1; + if (kernel_is_locked_down()) + return -EPERM; + err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval); if (err < 0) @@ -1916,6 +1919,9 @@ static int show_devs(struct seq_file *m, void *data) int err; u32 retval = -1; + if (kernel_is_locked_down()) + return -EPERM; + err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param, &retval); @@ -1940,6 +1946,9 @@ static int show_call(struct seq_file *m, void *data) union acpi_object *obj; acpi_status status; + if (kernel_is_locked_down()) + return -EPERM; + status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 1, asus->debug.method_id, &input, &output);
WARNING: multiple messages have this Message-ID (diff)
From: dhowells@redhat.com (David Howells) To: linux-security-module@vger.kernel.org Subject: [PATCH 15/24] asus-wmi: Restrict debugfs interface when the kernel is locked down Date: Wed, 05 Apr 2017 18:12:12 +0100 [thread overview] Message-ID: <149141233199.31282.4267532443918292855.stgit@warthog.procyon.org.uk> (raw) In-Reply-To: <149141219387.31282.6648284836568938717.stgit@warthog.procyon.org.uk> From: Matthew Garrett <matthew.garrett@nebula.com> We have no way of validating what all of the Asus WMI methods do on a given machine - and there's a risk that some will allow hardware state to be manipulated in such a way that arbitrary code can be executed in the kernel, circumventing module loading restrictions. Prevent that if the kernel is locked down. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: David Howells <dhowells@redhat.com> --- drivers/platform/x86/asus-wmi.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c index 8fe5890bf539..feef25076813 100644 --- a/drivers/platform/x86/asus-wmi.c +++ b/drivers/platform/x86/asus-wmi.c @@ -1900,6 +1900,9 @@ static int show_dsts(struct seq_file *m, void *data) int err; u32 retval = -1; + if (kernel_is_locked_down()) + return -EPERM; + err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval); if (err < 0) @@ -1916,6 +1919,9 @@ static int show_devs(struct seq_file *m, void *data) int err; u32 retval = -1; + if (kernel_is_locked_down()) + return -EPERM; + err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param, &retval); @@ -1940,6 +1946,9 @@ static int show_call(struct seq_file *m, void *data) union acpi_object *obj; acpi_status status; + if (kernel_is_locked_down()) + return -EPERM; + status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 1, asus->debug.method_id, &input, &output); -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2017-04-05 17:12 UTC|newest] Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-04-05 17:09 [PATCH 00/24] Kernel lockdown David Howells 2017-04-05 17:09 ` David Howells 2017-04-05 17:10 ` [PATCH 01/24] efi: Add EFI_SECURE_BOOT bit David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` [PATCH 02/24] Add the ability to lock down access to the running kernel image David Howells 2017-04-05 17:10 ` David Howells 2017-04-06 8:44 ` James Morris 2017-04-06 8:44 ` James Morris 2017-04-06 8:44 ` James Morris 2017-04-06 10:43 ` David Howells 2017-04-06 10:43 ` David Howells 2017-04-06 21:55 ` James Morris 2017-04-06 21:55 ` James Morris 2017-04-06 21:55 ` James Morris 2017-04-05 17:10 ` [PATCH 03/24] efi: Lock down the kernel if booted in secure boot mode David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` [PATCH 04/24] Enforce module signatures if the kernel is locked down David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` [PATCH 05/24] Restrict /dev/mem and /dev/kmem when " David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` [PATCH 06/24] Add a sysrq option to exit secure boot mode David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:10 ` [PATCH 07/24] kexec: Disable at runtime if the kernel is locked down David Howells 2017-04-05 17:10 ` David Howells 2017-04-05 17:11 ` [PATCH 08/24] Copy secure_boot flag in boot params across kexec reboot David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` [PATCH 09/24] kexec_file: Disable at runtime if securelevel has been set David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` [PATCH 10/24] hibernate: Disable when the kernel is locked down David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` [PATCH 11/24] uswsusp: " David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` [PATCH 12/24] PCI: Lock down BAR access " David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:11 ` [PATCH 13/24] x86: Lock down IO port " David Howells 2017-04-05 17:11 ` David Howells 2017-04-05 17:12 ` [PATCH 14/24] x86: Restrict MSR " David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:34 ` Kees Cook 2017-04-05 17:34 ` Kees Cook 2017-04-05 17:34 ` Kees Cook 2017-04-05 17:12 ` David Howells [this message] 2017-04-05 17:12 ` [PATCH 15/24] asus-wmi: Restrict debugfs interface " David Howells 2017-04-05 17:12 ` [PATCH 16/24] ACPI: Limit access to custom_method " David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:12 ` [PATCH 17/24] acpi: Ignore acpi_rsdp kernel param when the kernel has been " David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:12 ` [PATCH 18/24] acpi: Disable ACPI table override if the kernel is " David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 17:12 ` [PATCH 19/24] acpi: Disable APEI error injection " David Howells 2017-04-05 17:12 ` David Howells 2017-04-05 19:57 ` [PATCH 00/24] Kernel lockdown David Howells 2017-04-05 19:57 ` David Howells 2017-04-05 19:57 ` David Howells 2017-04-06 8:25 ` James Morris 2017-04-06 8:25 ` James Morris 2017-04-06 8:25 ` James Morris 2017-04-06 8:37 ` David Howells 2017-04-06 8:37 ` David Howells 2017-04-06 8:37 ` David Howells 2017-04-05 20:14 David Howells 2017-04-05 20:16 ` [PATCH 15/24] asus-wmi: Restrict debugfs interface when the kernel is locked down David Howells 2017-04-05 20:16 ` David Howells 2017-04-07 10:25 ` Andy Shevchenko 2017-04-07 10:25 ` Andy Shevchenko 2017-04-07 12:50 ` David Howells 2017-04-07 12:50 ` David Howells 2017-04-09 11:10 ` Andy Shevchenko 2017-04-09 11:10 ` Andy Shevchenko 2017-04-10 13:16 ` David Howells 2017-04-10 13:16 ` David Howells 2017-04-18 6:06 ` Andy Shevchenko 2017-04-18 6:06 ` Andy Shevchenko 2017-04-18 6:06 ` Andy Shevchenko 2017-04-18 14:34 ` Ben Hutchings 2017-04-18 14:34 ` Ben Hutchings 2017-04-18 14:55 ` David Howells 2017-04-18 14:55 ` David Howells 2017-04-18 14:55 ` David Howells 2017-04-18 15:19 ` Ben Hutchings 2017-04-18 15:19 ` Ben Hutchings 2017-04-18 15:34 ` David Howells 2017-04-18 15:34 ` David Howells 2017-04-18 15:34 ` David Howells 2017-04-18 15:30 ` David Howells 2017-04-18 15:30 ` David Howells 2017-04-18 17:39 ` Ben Hutchings 2017-04-18 17:39 ` Ben Hutchings 2017-04-18 17:39 ` Ben Hutchings
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