From: Matthew Garrett <matthew.garrett@nebula.com> To: linux-kernel@vger.kernel.org Cc: linux-security-module@vger.kernel.org, linux-efi@vger.kernel.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, Matthew Garrett <matthew.garrett@nebula.com> Subject: [PATCH 06/12] x86: Require CAP_COMPROMISE_KERNEL for IO port access Date: Mon, 18 Mar 2013 17:32:27 -0400 [thread overview] Message-ID: <1363642353-30749-6-git-send-email-matthew.garrett@nebula.com> (raw) In-Reply-To: <1363642353-30749-1-git-send-email-matthew.garrett@nebula.com> IO port access would permit users to gain access to PCI configuration registers, which in turn (on a lot of hardware) give access to MMIO register space. This would potentially permit root to trigger arbitrary DMA, so lock it down by default. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> --- arch/x86/kernel/ioport.c | 4 ++-- drivers/char/mem.c | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index 4ddaf66..f505995 100644 --- a/arch/x86/kernel/ioport.c +++ b/arch/x86/kernel/ioport.c @@ -28,7 +28,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) if ((from + num <= from) || (from + num > IO_BITMAP_BITS)) return -EINVAL; - if (turn_on && !capable(CAP_SYS_RAWIO)) + if (turn_on && (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))) return -EPERM; /* @@ -103,7 +103,7 @@ SYSCALL_DEFINE1(iopl, unsigned int, level) return -EINVAL; /* Trying to gain more privileges? */ if (level > old) { - if (!capable(CAP_SYS_RAWIO)) + if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL)) return -EPERM; } regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12); diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 2c644af..7eee4d8 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -597,6 +597,9 @@ static ssize_t write_port(struct file *file, const char __user *buf, unsigned long i = *ppos; const char __user *tmp = buf; + if (!capable(CAP_COMPROMISE_KERNEL)) + return -EPERM; + if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; while (count-- > 0 && i < 65536) { -- 1.8.1.2
WARNING: multiple messages have this Message-ID (diff)
From: Matthew Garrett <matthew.garrett@nebula.com> To: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org, linux-security-module@vger.kernel.org, linux-efi@vger.kernel.org, kexec@lists.infradead.org, Matthew Garrett <matthew.garrett@nebula.com> Subject: [PATCH 06/12] x86: Require CAP_COMPROMISE_KERNEL for IO port access Date: Mon, 18 Mar 2013 17:32:27 -0400 [thread overview] Message-ID: <1363642353-30749-6-git-send-email-matthew.garrett@nebula.com> (raw) In-Reply-To: <1363642353-30749-1-git-send-email-matthew.garrett@nebula.com> IO port access would permit users to gain access to PCI configuration registers, which in turn (on a lot of hardware) give access to MMIO register space. This would potentially permit root to trigger arbitrary DMA, so lock it down by default. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> --- arch/x86/kernel/ioport.c | 4 ++-- drivers/char/mem.c | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index 4ddaf66..f505995 100644 --- a/arch/x86/kernel/ioport.c +++ b/arch/x86/kernel/ioport.c @@ -28,7 +28,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) if ((from + num <= from) || (from + num > IO_BITMAP_BITS)) return -EINVAL; - if (turn_on && !capable(CAP_SYS_RAWIO)) + if (turn_on && (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))) return -EPERM; /* @@ -103,7 +103,7 @@ SYSCALL_DEFINE1(iopl, unsigned int, level) return -EINVAL; /* Trying to gain more privileges? */ if (level > old) { - if (!capable(CAP_SYS_RAWIO)) + if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL)) return -EPERM; } regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12); diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 2c644af..7eee4d8 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -597,6 +597,9 @@ static ssize_t write_port(struct file *file, const char __user *buf, unsigned long i = *ppos; const char __user *tmp = buf; + if (!capable(CAP_COMPROMISE_KERNEL)) + return -EPERM; + if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; while (count-- > 0 && i < 65536) { -- 1.8.1.2 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec
next prev parent reply other threads:[~2013-03-18 21:34 UTC|newest] Thread overview: 133+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-03-18 21:32 [PATCH 01/12] Security: Add CAP_COMPROMISE_KERNEL Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 02/12] SELinux: define mapping for CAP_COMPROMISE_KERNEL Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 03/12] Secure boot: Add a dummy kernel parameter that will switch on Secure Boot mode Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 04/12] efi: Enable secure boot lockdown automatically when enabled in firmware Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 05/12] PCI: Require CAP_COMPROMISE_KERNEL for PCI BAR access Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-27 15:03 ` Josh Boyer 2013-03-27 15:03 ` Josh Boyer 2013-03-27 15:08 ` Kyle McMartin 2013-03-27 15:08 ` Kyle McMartin 2013-03-28 12:46 ` Josh Boyer 2013-03-28 12:46 ` Josh Boyer 2013-03-18 21:32 ` Matthew Garrett [this message] 2013-03-18 21:32 ` [PATCH 06/12] x86: Require CAP_COMPROMISE_KERNEL for IO port access Matthew Garrett 2013-03-20 1:00 ` H. Peter Anvin 2013-03-20 1:00 ` H. Peter Anvin 2013-03-18 21:32 ` [PATCH 07/12] ACPI: Limit access to custom_method Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 08/12] asus-wmi: Restrict debugfs interface Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 09/12] Require CAP_COMPROMISE_KERNEL for /dev/mem and /dev/kmem access Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 10/12] acpi: Ignore acpi_rsdp kernel parameter in a secure boot environment Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-19 8:47 ` Dave Young 2013-03-19 8:47 ` Dave Young 2013-03-19 8:47 ` Dave Young 2013-03-19 11:19 ` Josh Boyer 2013-03-19 11:19 ` Josh Boyer 2013-03-19 11:19 ` Josh Boyer 2013-03-19 17:07 ` [PATCH v2] " Josh Boyer 2013-03-19 17:07 ` Josh Boyer 2013-03-18 21:32 ` [PATCH 11/12] x86: Require CAP_COMPROMISE_KERNEL for MSR writing Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` [PATCH 12/12] kexec: Require CAP_SYS_COMPROMISE_KERNEL Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-18 21:32 ` Matthew Garrett 2013-03-19 4:47 ` [PATCH 01/12] Security: Add CAP_COMPROMISE_KERNEL James Morris 2013-03-19 4:47 ` James Morris 2013-03-19 4:47 ` James Morris 2013-03-20 1:03 ` H. Peter Anvin 2013-03-20 1:03 ` H. Peter Anvin 2013-03-20 16:41 ` Mimi Zohar 2013-03-20 16:41 ` Mimi Zohar 2013-03-20 16:49 ` Matthew Garrett 2013-03-20 16:49 ` Matthew Garrett 2013-03-20 16:49 ` Matthew Garrett 2013-03-20 16:49 ` Matthew Garrett 2013-03-20 18:01 ` Mimi Zohar 2013-03-20 18:01 ` Mimi Zohar 2013-03-20 18:01 ` Mimi Zohar 2013-03-20 18:12 ` Matthew Garrett 2013-03-20 18:12 ` Matthew Garrett 2013-03-20 18:12 ` Matthew Garrett 2013-03-20 18:12 ` Matthew Garrett 2013-03-20 19:16 ` Mimi Zohar 2013-03-20 19:16 ` Mimi Zohar 2013-03-20 19:16 ` Mimi Zohar 2013-03-20 19:16 ` Mimi Zohar 2013-03-20 20:37 ` Matthew Garrett 2013-03-20 20:37 ` Matthew Garrett 2013-03-20 20:37 ` Matthew Garrett 2013-03-20 20:37 ` Matthew Garrett 2013-03-20 21:11 ` Mimi Zohar 2013-03-20 21:11 ` Mimi Zohar 2013-03-20 21:11 ` Mimi Zohar 2013-03-20 21:18 ` Matthew Garrett 2013-03-20 21:18 ` Matthew Garrett 2013-03-20 21:18 ` Matthew Garrett 2013-03-20 21:18 ` Matthew Garrett 2013-03-21 13:43 ` Vivek Goyal 2013-03-21 13:43 ` Vivek Goyal 2013-03-21 13:43 ` Vivek Goyal 2013-03-21 13:43 ` Vivek Goyal 2013-03-21 15:37 ` Serge E. Hallyn 2013-03-21 15:37 ` Serge E. Hallyn 2013-03-21 15:37 ` Serge E. Hallyn 2013-03-21 15:37 ` Serge E. Hallyn 2013-03-21 15:52 ` Vivek Goyal 2013-03-21 15:52 ` Vivek Goyal 2013-03-21 15:52 ` Vivek Goyal 2013-03-21 15:52 ` Vivek Goyal 2013-03-21 15:58 ` Serge E. Hallyn 2013-03-21 15:58 ` Serge E. Hallyn 2013-03-21 15:58 ` Serge E. Hallyn 2013-03-21 15:58 ` Serge E. Hallyn 2013-03-21 16:04 ` Vivek Goyal 2013-03-21 16:04 ` Vivek Goyal 2013-03-21 16:04 ` Vivek Goyal 2013-03-21 16:19 ` Serge E. Hallyn 2013-03-21 16:19 ` Serge E. Hallyn 2013-03-21 16:19 ` Serge E. Hallyn 2013-03-21 16:19 ` Serge E. Hallyn 2013-03-21 17:15 ` Vivek Goyal 2013-03-21 17:15 ` Vivek Goyal 2013-03-21 17:15 ` Vivek Goyal 2013-03-21 17:15 ` Vivek Goyal 2013-03-21 1:58 ` James Morris 2013-03-21 1:58 ` James Morris 2013-03-19 7:18 ` Yves-Alexis Perez 2013-03-19 7:18 ` Yves-Alexis Perez 2013-03-20 1:02 ` H. Peter Anvin 2013-03-20 1:02 ` H. Peter Anvin 2013-03-20 1:05 ` H. Peter Anvin 2013-03-20 1:05 ` H. Peter Anvin 2013-03-20 13:15 ` Matthew Garrett 2013-03-20 13:15 ` Matthew Garrett 2013-03-20 13:15 ` Matthew Garrett 2013-03-20 13:15 ` Matthew Garrett 2013-03-20 15:03 ` H. Peter Anvin 2013-03-20 15:03 ` H. Peter Anvin 2013-03-20 15:03 ` H. Peter Anvin 2013-03-20 15:03 ` H. Peter Anvin 2013-03-20 15:14 ` Matthew Garrett 2013-03-20 15:14 ` Matthew Garrett 2013-03-20 15:14 ` Matthew Garrett 2013-03-20 15:14 ` Matthew Garrett 2013-03-20 16:45 ` H. Peter Anvin 2013-03-20 16:45 ` H. Peter Anvin 2013-03-20 16:45 ` H. Peter Anvin 2013-03-20 1:05 [PATCH 06/12] x86: Require CAP_COMPROMISE_KERNEL for IO port access Matthew Garrett 2013-03-20 1:05 ` Matthew Garrett 2013-03-20 1:05 ` Matthew Garrett 2013-03-20 1:05 ` Matthew Garrett
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