From: David Howells <dhowells@redhat.com> To: linux-security-module@vger.kernel.org Cc: gnomes@lxorguk.ukuu.org.uk, linux-efi@vger.kernel.org, matthew.garrett@nebula.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, jforbes@redhat.com Subject: [PATCH 05/27] kexec: Disable at runtime if the kernel is locked down Date: Thu, 19 Oct 2017 15:51:09 +0100 [thread overview] Message-ID: <150842466996.7923.17995994984545441369.stgit@warthog.procyon.org.uk> (raw) In-Reply-To: <150842463163.7923.11081723749106843698.stgit@warthog.procyon.org.uk> From: Matthew Garrett <matthew.garrett@nebula.com> kexec permits the loading and execution of arbitrary code in ring 0, which is something that lock-down is meant to prevent. It makes sense to disable kexec in this situation. This does not affect kexec_file_load() which can check for a signature on the image to be booted. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> cc: kexec@lists.infradead.org --- kernel/kexec.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/kexec.c b/kernel/kexec.c index e62ec4dc6620..7dadfed9b676 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -202,6 +202,13 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, return -EPERM; /* + * kexec can be used to circumvent module loading restrictions, so + * prevent loading in that case + */ + if (kernel_is_locked_down("kexec of unsigned images")) + return -EPERM; + + /* * Verify we have a legal set of flags * This leaves us room for future extensions. */
WARNING: multiple messages have this Message-ID (diff)
From: dhowells@redhat.com (David Howells) To: linux-security-module@vger.kernel.org Subject: [PATCH 05/27] kexec: Disable at runtime if the kernel is locked down Date: Thu, 19 Oct 2017 15:51:09 +0100 [thread overview] Message-ID: <150842466996.7923.17995994984545441369.stgit@warthog.procyon.org.uk> (raw) In-Reply-To: <150842463163.7923.11081723749106843698.stgit@warthog.procyon.org.uk> From: Matthew Garrett <matthew.garrett@nebula.com> kexec permits the loading and execution of arbitrary code in ring 0, which is something that lock-down is meant to prevent. It makes sense to disable kexec in this situation. This does not affect kexec_file_load() which can check for a signature on the image to be booted. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> cc: kexec at lists.infradead.org --- kernel/kexec.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/kexec.c b/kernel/kexec.c index e62ec4dc6620..7dadfed9b676 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -202,6 +202,13 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, return -EPERM; /* + * kexec can be used to circumvent module loading restrictions, so + * prevent loading in that case + */ + if (kernel_is_locked_down("kexec of unsigned images")) + return -EPERM; + + /* * Verify we have a legal set of flags * This leaves us room for future extensions. */ -- 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:[~2017-10-19 14:51 UTC|newest] Thread overview: 359+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-10-19 14:50 [PATCH 00/27] security, efi: Add kernel lockdown David Howells 2017-10-19 14:50 ` David Howells 2017-10-19 14:50 ` David Howells 2017-10-19 14:50 ` [PATCH 01/27] Add the ability to lock down access to the running kernel image David Howells 2017-10-19 14:50 ` David Howells 2017-10-20 23:19 ` James Morris 2017-10-20 23:19 ` James Morris 2017-10-19 14:50 ` [PATCH 02/27] Add a SysRq option to lift kernel lockdown David Howells 2017-10-19 14:50 ` David Howells 2017-10-19 17:20 ` Randy Dunlap 2017-10-19 17:20 ` Randy Dunlap 2017-10-19 17:20 ` Randy Dunlap 2017-10-19 22:12 ` David Howells 2017-10-19 22:12 ` David Howells 2017-10-19 22:12 ` David Howells 2017-11-07 17:39 ` Thiago Jung Bauermann 2017-11-07 17:39 ` Thiago Jung Bauermann 2017-11-07 22:56 ` David Howells 2017-11-07 22:56 ` David Howells 2017-10-19 14:50 ` [PATCH 03/27] Enforce module signatures if the kernel is locked down David Howells 2017-10-19 14:50 ` David Howells 2017-10-20 6:33 ` joeyli 2017-10-20 6:33 ` joeyli 2017-10-20 6:33 ` joeyli 2017-10-20 23:21 ` James Morris 2017-10-20 23:21 ` James Morris 2017-10-27 18:48 ` Mimi Zohar 2017-10-27 18:48 ` Mimi Zohar 2017-10-30 17:00 ` David Howells 2017-10-30 17:00 ` David Howells 2017-10-30 17:52 ` Mimi Zohar 2017-10-30 17:52 ` Mimi Zohar 2017-11-02 17:22 ` David Howells 2017-11-02 17:22 ` David Howells 2017-11-02 17:22 ` David Howells 2017-11-02 19:13 ` Mimi Zohar 2017-11-02 19:13 ` Mimi Zohar 2017-11-02 21:30 ` David Howells 2017-11-02 21:30 ` David Howells 2017-11-02 21:30 ` David Howells 2017-11-02 21:41 ` Mimi Zohar 2017-11-02 21:41 ` Mimi Zohar 2017-11-02 21:41 ` Mimi Zohar 2017-11-02 22:01 ` David Howells 2017-11-02 22:01 ` David Howells 2017-11-02 22:01 ` David Howells 2017-11-02 22:18 ` Mimi Zohar 2017-11-02 22:18 ` Mimi Zohar 2017-10-19 14:51 ` [PATCH 04/27] Restrict /dev/mem and /dev/kmem when " David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:37 ` joeyli 2017-10-20 6:37 ` joeyli 2017-10-20 23:21 ` James Morris 2017-10-20 23:21 ` James Morris 2017-10-19 14:51 ` David Howells [this message] 2017-10-19 14:51 ` [PATCH 05/27] kexec: Disable at runtime if " David Howells 2017-10-20 6:38 ` joeyli 2017-10-20 6:38 ` joeyli 2017-10-20 23:22 ` James Morris 2017-10-20 23:22 ` James Morris 2017-10-19 14:51 ` [PATCH 06/27] Copy secure_boot flag in boot params across kexec reboot David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:40 ` joeyli 2017-10-20 6:40 ` joeyli 2017-10-20 6:40 ` joeyli 2017-10-19 14:51 ` [PATCH 07/27] kexec_file: Disable at runtime if securelevel has been set David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 23:26 ` James Morris 2017-10-20 23:26 ` James Morris 2017-10-23 15:54 ` Mimi Zohar 2017-10-23 15:54 ` Mimi Zohar 2017-10-23 15:54 ` Mimi Zohar 2017-10-26 7:42 ` joeyli 2017-10-26 7:42 ` joeyli 2017-10-26 14:17 ` Mimi Zohar 2017-10-26 14:17 ` Mimi Zohar 2017-10-27 19:30 ` Mimi Zohar 2017-10-27 19:30 ` Mimi Zohar 2017-10-27 19:32 ` Mimi Zohar 2017-10-27 19:32 ` Mimi Zohar 2017-10-27 19:32 ` Mimi Zohar 2017-10-28 8:34 ` joeyli 2017-10-28 8:34 ` joeyli 2017-10-29 22:26 ` Mimi Zohar 2017-10-29 22:26 ` Mimi Zohar 2017-10-29 22:26 ` Mimi Zohar 2017-10-30 9:00 ` David Howells 2017-10-30 9:00 ` David Howells 2017-10-30 12:01 ` Mimi Zohar 2017-10-30 12:01 ` Mimi Zohar 2017-10-26 15:02 ` David Howells 2017-10-26 15:02 ` David Howells 2017-10-26 15:46 ` Mimi Zohar 2017-10-26 15:46 ` Mimi Zohar 2017-10-26 15:46 ` Mimi Zohar 2017-10-30 15:49 ` David Howells 2017-10-30 15:49 ` David Howells 2017-10-30 16:43 ` Mimi Zohar 2017-10-30 16:43 ` Mimi Zohar 2017-10-30 16:43 ` Mimi Zohar 2017-11-02 17:00 ` David Howells 2017-11-02 17:00 ` David Howells 2017-10-26 14:51 ` David Howells 2017-10-26 14:51 ` David Howells 2017-10-26 14:51 ` David Howells 2017-11-02 17:29 ` David Howells 2017-11-02 17:29 ` David Howells 2017-11-02 17:29 ` David Howells 2017-10-19 14:51 ` [PATCH 08/27] hibernate: Disable when the kernel is locked down David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:40 ` joeyli 2017-10-20 6:40 ` joeyli 2017-10-20 6:40 ` joeyli 2017-10-19 14:51 ` [PATCH 09/27] uswsusp: " David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:41 ` joeyli 2017-10-20 6:41 ` joeyli 2017-10-20 23:29 ` James Morris 2017-10-20 23:29 ` James Morris 2017-10-20 23:29 ` James Morris 2017-10-19 14:51 ` [PATCH 10/27] PCI: Lock down BAR access " David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:42 ` joeyli 2017-10-20 6:42 ` joeyli 2017-10-20 6:42 ` joeyli 2017-10-19 14:51 ` [PATCH 11/27] x86: Lock down IO port " David Howells 2017-10-19 14:51 ` David Howells 2017-10-20 6:43 ` joeyli 2017-10-20 6:43 ` joeyli 2017-10-19 14:52 ` [PATCH 12/27] x86/msr: Restrict MSR " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:43 ` joeyli 2017-10-20 6:43 ` joeyli 2017-10-20 18:09 ` Alan Cox 2017-10-20 18:09 ` Alan Cox 2017-10-20 20:48 ` David Howells 2017-10-20 20:48 ` David Howells 2017-10-20 20:48 ` David Howells 2017-10-21 4:39 ` joeyli 2017-10-21 4:39 ` joeyli 2017-10-23 14:49 ` David Howells 2017-10-23 14:49 ` David Howells 2017-10-23 14:49 ` David Howells 2017-10-25 14:03 ` joeyli 2017-10-25 14:03 ` joeyli 2017-10-19 14:52 ` [PATCH 13/27] asus-wmi: Restrict debugfs interface " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:44 ` joeyli 2017-10-20 6:44 ` joeyli 2017-10-19 14:52 ` [PATCH 14/27] ACPI: Limit access to custom_method " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:45 ` joeyli 2017-10-20 6:45 ` joeyli 2017-10-19 14:52 ` [PATCH 15/27] acpi: Ignore acpi_rsdp kernel param when the kernel has been " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:45 ` joeyli 2017-10-20 6:45 ` joeyli 2017-10-19 14:52 ` [PATCH 16/27] acpi: Disable ACPI table override if the kernel is " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:46 ` joeyli 2017-10-20 6:46 ` joeyli 2017-10-20 6:46 ` joeyli 2017-10-19 14:52 ` [PATCH 17/27] acpi: Disable APEI error injection " David Howells 2017-10-19 14:52 ` David Howells 2017-10-20 6:47 ` joeyli 2017-10-20 6:47 ` joeyli 2017-10-20 6:47 ` joeyli 2017-10-19 14:52 ` [PATCH 18/27] bpf: Restrict kernel image access functions when " David Howells 2017-10-19 14:52 ` David Howells 2017-10-19 22:18 ` Alexei Starovoitov 2017-10-19 22:18 ` Alexei Starovoitov 2017-10-20 2:47 ` joeyli 2017-10-20 2:47 ` joeyli 2017-10-20 8:08 ` David Howells 2017-10-20 8:08 ` David Howells 2017-10-20 15:57 ` jlee 2017-10-20 15:57 ` jlee at suse.com 2017-10-20 23:00 ` Alexei Starovoitov 2017-10-23 14:51 ` David Howells 2017-10-20 16:03 ` David Howells 2017-10-20 16:03 ` David Howells 2017-10-20 16:03 ` David Howells 2017-10-20 16:43 ` jlee 2017-10-20 16:43 ` jlee at suse.com 2017-10-23 14:53 ` David Howells 2017-10-23 14:53 ` David Howells 2017-10-25 7:07 ` joeyli 2017-10-25 7:07 ` joeyli 2017-10-25 7:07 ` joeyli 2017-10-19 22:48 ` David Howells 2017-10-19 22:48 ` David Howells 2017-10-19 23:31 ` Alexei Starovoitov 2017-10-19 23:31 ` Alexei Starovoitov 2017-10-19 23:31 ` Alexei Starovoitov 2017-11-09 17:15 ` David Howells 2017-11-09 17:15 ` David Howells 2017-10-19 14:52 ` [PATCH 19/27] scsi: Lock down the eata driver David Howells 2017-10-19 14:52 ` David Howells 2017-10-19 14:53 ` [PATCH 20/27] Prohibit PCMCIA CIS storage when the kernel is locked down David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 14:53 ` [PATCH 21/27] Lock down TIOCSSERIAL David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 14:53 ` [PATCH 22/27] Lock down module params that specify hardware parameters (eg. ioport) David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 14:53 ` [PATCH 23/27] x86/mmiotrace: Lock down the testmmiotrace module David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 14:53 ` [PATCH 24/27] debugfs: Disallow use of debugfs files when the kernel is locked down David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 14:53 ` [PATCH 25/27] Lock down /proc/kcore David Howells 2017-10-19 14:53 ` David Howells 2017-10-21 2:11 ` James Morris 2017-10-21 2:11 ` James Morris 2017-10-23 14:56 ` David Howells 2017-10-23 14:56 ` David Howells 2017-10-19 14:53 ` [PATCH 26/27] efi: Add an EFI_SECURE_BOOT flag to indicate secure boot mode David Howells 2017-10-19 14:53 ` David Howells 2017-10-21 2:19 ` James Morris 2017-10-21 2:19 ` James Morris 2017-10-21 2:19 ` James Morris 2017-10-23 14:58 ` David Howells 2017-10-23 14:58 ` David Howells 2017-10-19 14:53 ` [PATCH 27/27] efi: Lock down the kernel if booted in " David Howells 2017-10-19 14:53 ` David Howells 2017-10-19 22:39 ` [PATCH 00/27] security, efi: Add kernel lockdown David Howells 2017-10-19 22:39 ` David Howells 2017-10-19 22:39 ` David Howells 2017-10-23 14:34 ` [PATCH 04/27] Restrict /dev/mem and /dev/kmem when the kernel is locked down David Howells 2017-10-23 14:34 ` David Howells 2017-10-23 14:34 ` David Howells 2017-10-24 10:48 ` Ethan Zhao 2017-10-24 10:48 ` Ethan Zhao 2017-10-24 10:48 ` Ethan Zhao 2017-10-24 14:56 ` David Howells 2017-10-24 14:56 ` David Howells 2017-11-02 22:01 ` [PATCH 00/27] security, efi: Add kernel lockdown Mimi Zohar 2017-11-02 22:01 ` Mimi Zohar 2017-11-02 22:04 ` Firmware signing -- " David Howells 2017-11-02 22:04 ` David Howells 2017-11-02 22:04 ` David Howells 2017-11-02 22:10 ` Mimi Zohar 2017-11-02 22:10 ` Mimi Zohar 2017-11-07 23:07 ` Luis R. Rodriguez 2017-11-07 23:07 ` Luis R. Rodriguez 2017-11-07 23:07 ` Luis R. Rodriguez 2017-11-08 6:15 ` AKASHI, Takahiro 2017-11-08 6:15 ` AKASHI, Takahiro 2017-11-08 6:15 ` AKASHI, Takahiro 2017-11-08 19:46 ` Luis R. Rodriguez 2017-11-08 19:46 ` Luis R. Rodriguez 2017-11-08 19:46 ` Luis R. Rodriguez 2017-11-09 1:48 ` AKASHI, Takahiro 2017-11-09 1:48 ` AKASHI, Takahiro 2017-11-09 1:48 ` AKASHI, Takahiro 2017-11-09 2:17 ` Mimi Zohar 2017-11-09 2:17 ` Mimi Zohar 2017-11-09 4:46 ` AKASHI, Takahiro 2017-11-09 4:46 ` AKASHI, Takahiro 2017-11-10 13:37 ` Mimi Zohar 2017-11-10 13:37 ` Mimi Zohar 2017-11-11 2:32 ` Alan Cox 2017-11-11 2:32 ` Alan Cox 2017-11-11 2:32 ` Alan Cox 2017-11-13 11:49 ` Mimi Zohar 2017-11-13 11:49 ` Mimi Zohar 2017-11-13 17:42 ` Luis R. Rodriguez 2017-11-13 17:42 ` Luis R. Rodriguez 2017-11-13 17:42 ` Luis R. Rodriguez 2017-11-13 21:08 ` Alan Cox 2017-11-13 21:08 ` Alan Cox 2017-12-04 19:51 ` Luis R. Rodriguez 2017-12-04 19:51 ` Luis R. Rodriguez 2017-12-04 19:51 ` Luis R. Rodriguez 2017-12-07 15:32 ` Alan Cox 2017-12-07 15:32 ` Alan Cox 2017-12-07 15:32 ` Alan Cox 2017-11-13 21:44 ` David Howells 2017-11-13 21:44 ` David Howells 2017-11-13 22:09 ` Linus Torvalds 2017-11-13 22:09 ` Linus Torvalds 2017-11-13 22:09 ` Linus Torvalds 2017-11-14 0:20 ` Alan Cox 2017-11-14 0:20 ` Alan Cox 2017-11-14 0:20 ` Alan Cox 2017-11-14 12:21 ` Mimi Zohar 2017-11-14 12:21 ` Mimi Zohar 2017-11-14 12:38 ` Greg Kroah-Hartman 2017-11-14 12:38 ` Greg Kroah-Hartman 2017-11-14 13:17 ` Mimi Zohar 2017-11-14 13:17 ` Mimi Zohar 2017-11-14 13:17 ` Mimi Zohar 2017-11-14 17:34 ` Linus Torvalds 2017-11-14 17:34 ` Linus Torvalds 2017-11-14 17:34 ` Linus Torvalds 2017-11-14 19:58 ` Matthew Garrett 2017-11-14 19:58 ` Matthew Garrett 2017-11-14 19:58 ` Matthew Garrett 2017-11-14 20:18 ` Linus Torvalds 2017-11-14 20:18 ` Linus Torvalds 2017-11-14 20:18 ` Linus Torvalds 2017-11-14 20:31 ` Matthew Garrett 2017-11-14 20:31 ` Matthew Garrett 2017-11-14 20:31 ` Matthew Garrett 2017-11-14 20:35 ` Linus Torvalds 2017-11-14 20:35 ` Linus Torvalds 2017-11-14 20:37 ` Matthew Garrett 2017-11-14 20:37 ` Matthew Garrett 2017-11-14 20:37 ` Matthew Garrett 2017-11-14 20:50 ` Luis R. Rodriguez 2017-11-14 20:50 ` Luis R. Rodriguez 2017-11-14 20:55 ` Matthew Garrett 2017-11-14 20:55 ` Matthew Garrett 2017-11-14 20:55 ` Matthew Garrett 2017-11-14 22:14 ` James Bottomley 2017-11-14 22:14 ` James Bottomley 2017-11-14 22:17 ` Matthew Garrett 2017-11-14 22:17 ` Matthew Garrett 2017-11-14 22:17 ` Matthew Garrett 2017-11-14 22:31 ` James Bottomley 2017-11-14 22:31 ` James Bottomley 2017-11-14 22:31 ` James Bottomley 2017-11-14 22:34 ` Matthew Garrett 2017-11-14 22:34 ` Matthew Garrett 2017-11-14 22:34 ` Matthew Garrett 2017-11-15 11:49 ` Mimi Zohar 2017-11-15 11:49 ` Mimi Zohar 2017-11-15 11:49 ` Mimi Zohar 2017-11-15 17:52 ` Luis R. Rodriguez 2017-11-15 17:52 ` Luis R. Rodriguez 2017-11-15 17:52 ` Luis R. Rodriguez 2017-11-15 19:56 ` Mimi Zohar 2017-11-15 19:56 ` Mimi Zohar 2017-11-15 20:46 ` Luis R. Rodriguez 2017-11-15 20:46 ` Luis R. Rodriguez 2017-11-16 0:05 ` Mimi Zohar 2017-11-16 0:05 ` Mimi Zohar 2017-12-05 10:27 ` Pavel Machek 2017-12-05 10:27 ` Pavel Machek 2017-12-07 23:02 ` Luis R. Rodriguez 2017-12-07 23:02 ` Luis R. Rodriguez 2017-12-07 23:02 ` Luis R. Rodriguez 2017-12-08 17:11 ` Alan Cox 2017-12-08 17:11 ` Alan Cox 2017-12-08 17:11 ` Alan Cox 2017-11-10 1:46 ` Luis R. Rodriguez 2017-11-10 1:46 ` Luis R. Rodriguez 2017-11-10 1:46 ` Luis R. Rodriguez 2017-11-10 13:45 ` Mimi Zohar 2017-11-10 13:45 ` Mimi Zohar 2017-11-10 13:45 ` Mimi Zohar 2017-11-13 18:50 ` Luis R. Rodriguez 2017-11-13 18:50 ` Luis R. Rodriguez 2017-11-13 18:50 ` Luis R. Rodriguez 2017-11-13 19:08 ` Luis R. Rodriguez 2017-11-13 19:08 ` Luis R. Rodriguez 2017-11-13 19:08 ` Luis R. Rodriguez 2017-11-08 20:01 ` Mimi Zohar 2017-11-08 20:01 ` Mimi Zohar 2017-11-08 20:09 ` Luis R. Rodriguez 2017-11-08 20:09 ` Luis R. Rodriguez
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=150842466996.7923.17995994984545441369.stgit@warthog.procyon.org.uk \ --to=dhowells@redhat.com \ --cc=gnomes@lxorguk.ukuu.org.uk \ --cc=gregkh@linuxfoundation.org \ --cc=jforbes@redhat.com \ --cc=linux-efi@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-security-module@vger.kernel.org \ --cc=matthew.garrett@nebula.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.