- 23 Jan, 2018 20 commits
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Takashi Iwai authored
commit e4c9fd10 upstream. There is another Dell XPS 13 variant (SSID 1028:082a) that requires the existing fixup for reducing the headphone noise. This patch adds the quirk entry for that. BugLink: http://lkml.kernel.org/r/CAHXyb9ZCZJzVisuBARa+UORcjRERV8yokez=DP1_5O5isTz0ZA@mail.gmail.comReported-and-tested-by:
Francisco G. <frangio.1@gmail.com> Signed-off-by:
Takashi Iwai <tiwai@suse.de> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Takashi Iwai authored
commit 23b19b7b upstream. muldiv32() contains a snd_BUG_ON() (which is morphed as WARN_ON() with debug option) for checking the case of 0 / 0. This would be helpful if this happens only as a logical error; however, since the hw refine is performed with any data set provided by user, the inconsistent values that can trigger such a condition might be passed easily. Actually, syzbot caught this by passing some zero'ed old hw_params ioctl. So, having snd_BUG_ON() there is simply superfluous and rather harmful to give unnecessary confusions. Let's get rid of it. Reported-by: syzbot+7e6ee55011deeebce15d@syzkaller.appspotmail.com Signed-off-by:
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Takashi Iwai authored
commit b3defb79 upstream. The ALSA sequencer ioctls have no protection against racy calls while the concurrent operations may lead to interfere with each other. As reported recently, for example, the concurrent calls of setting client pool with a combination of write calls may lead to either the unkillable dead-lock or UAF. As a slightly big hammer solution, this patch introduces the mutex to make each ioctl exclusive. Although this may reduce performance via parallel ioctl calls, usually it's not demanded for sequencer usages, hence it should be negligible. Reported-by:
Luo Quan <a4651386@163.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Reviewed-by:
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Li Jinyue authored
commit fbe0e839 upstream. UBSAN reports signed integer overflow in kernel/futex.c: UBSAN: Undefined behaviour in kernel/futex.c:2041:18 signed integer overflow: 0 - -2147483648 cannot be represented in type 'int' Add a sanity check to catch negative values of nr_wake and nr_requeue. Signed-off-by:
Li Jinyue <lijinyue@huawei.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: dvhart@infradead.org Link: https://lkml.kernel.org/r/1513242294-31786-1-git-send-email-lijinyue@huawei.comSigned-off-by:
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Peter Zijlstra authored
commit c1e2f0ea upstream. Julia reported futex state corruption in the following scenario: waiter waker stealer (prio > waiter) futex(WAIT_REQUEUE_PI, uaddr, uaddr2, timeout=[N ms]) futex_wait_requeue_pi() futex_wait_queue_me() freezable_schedule() <scheduled out> futex(LOCK_PI, uaddr2) futex(CMP_REQUEUE_PI, uaddr, uaddr2, 1, 0) /* requeues waiter to uaddr2 */ futex(UNLOCK_PI, uaddr2) wake_futex_pi() cmp_futex_value_locked(uaddr2, waiter) wake_up_q() <woken by waker> <hrtimer_wakeup() fires, clears sleeper->task> futex(LOCK_PI, uaddr2) __rt_mutex_start_proxy_lock() try_to_take_rt_mutex() /* steals lock */ rt_mutex_set_owner(lock, stealer) <preempted> <scheduled in> rt_mutex_wait_proxy_lock() __rt_mutex_slowlock() try_to_take_rt_mutex() /* fails, lock held by stealer */ if (timeout && !timeout->task) return -ETIMEDOUT; fixup_owner() /* lock wasn't acquired, so, fixup_pi_state_owner skipped */ return -ETIMEDOUT; /* At this point, we've returned -ETIMEDOUT to userspace, but the * futex word shows waiter to be the owner, and the pi_mutex has * stealer as the owner */ futex_lock(LOCK_PI, uaddr2) -> bails with EDEADLK, futex word says we're owner. And suggested that what commit: 73d786bd ("futex: Rework inconsistent rt_mutex/futex_q state") removes from fixup_owner() looks to be just what is needed. And indeed it is -- I completely missed that requeue_pi could also result in this case. So we need to restore that, except that subsequent patches, like commit: 16ffa12d ("futex: Pull rt_mutex_futex_unlock() out from under hb->lock") changed all the locking rules. Even without that, the sequence: - if (rt_mutex_futex_trylock(&q->pi_state->pi_mutex)) { - locked = 1; - goto out; - } - raw_spin_lock_irq(&q->pi_state->pi_mutex.wait_lock); - owner = rt_mutex_owner(&q->pi_state->pi_mutex); - if (!owner) - owner = rt_mutex_next_owner(&q->pi_state->pi_mutex); - raw_spin_unlock_irq(&q->pi_state->pi_mutex.wait_lock); - ret = fixup_pi_state_owner(uaddr, q, owner); already suggests there were races; otherwise we'd never have to look at next_owner. So instead of doing 3 consecutive wait_lock sections with who knows what races, we do it all in a single section. Additionally, the usage of pi_state->owner in fixup_owner() was only safe because only the rt_mutex owner would modify it, which this additional case wrecks. Luckily the values can only change away and not to the value we're testing, this means we can do a speculative test and double check once we have the wait_lock. Fixes: 73d786bd ("futex: Rework inconsistent rt_mutex/futex_q state") Reported-by:
Julia Cartwright <julia@ni.com> Reported-by:
Gratian Crisan <gratian.crisan@ni.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by:
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Oliver O'Halloran authored
commit 6e032b35 upstream. New device-tree properties are available which tell the hypervisor settings related to the RFI flush. Use them to determine the appropriate flush instruction to use, and whether the flush is required. Signed-off-by:
Oliver O'Halloran <oohall@gmail.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Michael Neuling authored
commit 8989d568 upstream. A new hypervisor call is available which tells the guest settings related to the RFI flush. Use it to query the appropriate flush instruction(s), and whether the flush is required. Signed-off-by:
Michael Neuling <mikey@neuling.org> Signed-off-by:
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Michael Ellerman authored
commit bc9c9304 upstream. Because there may be some performance overhead of the RFI flush, add kernel command line options to disable it. We add a sensibly named 'no_rfi_flush' option, but we also hijack the x86 option 'nopti'. The RFI flush is not the same as KPTI, but if we see 'nopti' we can guess that the user is trying to avoid any overhead of Meltdown mitigations, and it means we don't have to educate every one about a different command line option. Signed-off-by:
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Michael Ellerman authored
commit aa8a5e00 upstream. On some CPUs we can prevent the Meltdown vulnerability by flushing the L1-D cache on exit from kernel to user mode, and from hypervisor to guest. This is known to be the case on at least Power7, Power8 and Power9. At this time we do not know the status of the vulnerability on other CPUs such as the 970 (Apple G5), pasemi CPUs (AmigaOne X1000) or Freescale CPUs. As more information comes to light we can enable this, or other mechanisms on those CPUs. The vulnerability occurs when the load of an architecturally inaccessible memory region (eg. userspace load of kernel memory) is speculatively executed to the point where its result can influence the address of a subsequent speculatively executed load. In order for that to happen, the first load must hit in the L1, because before the load is sent to the L2 the permission check is performed. Therefore if no kernel addresses hit in the L1 the vulnerability can not occur. We can ensure that is the case by flushing the L1 whenever we return to userspace. Similarly for hypervisor vs guest. In order to flush the L1-D cache on exit, we add a section of nops at each (h)rfi location that returns to a lower privileged context, and patch that with some sequence. Newer firmwares are able to advertise to us that there is a special nop instruction that flushes the L1-D. If we do not see that advertised, we fall back to doing a displacement flush in software. For guest kernels we support migration between some CPU versions, and different CPUs may use different flush instructions. So that we are prepared to migrate to a machine with a different flush instruction activated, we may have to patch more than one flush instruction at boot if the hypervisor tells us to. In the end this patch is mostly the work of Nicholas Piggin and Michael Ellerman. However a cast of thousands contributed to analysis of the issue, earlier versions of the patch, back ports testing etc. Many thanks to all of them. Tested-by:
Jon Masters <jcm@redhat.com> Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Signed-off-by:
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Nicholas Piggin authored
commit c7305645 upstream. In the SLB miss handler we may be returning to user or kernel. We need to add a check early on and save the result in the cr4 register, and then we bifurcate the return path based on that. Signed-off-by:
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Nicholas Piggin authored
commit a08f828c upstream. Similar to the syscall return path, in fast_exception_return we may be returning to user or kernel context. We already have a test for that, because we conditionally restore r13. So use that existing test and branch, and bifurcate the return based on that. Signed-off-by:
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Nicholas Piggin authored
commit b8e90cb7 upstream. In the syscall exit path we may be returning to user or kernel context. We already have a test for that, because we conditionally restore r13. So use that existing test and branch, and bifurcate the return based on that. Signed-off-by:
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Nicholas Piggin authored
commit 222f20f1 upstream. This commit does simple conversions of rfi/rfid to the new macros that include the expected destination context. By simple we mean cases where there is a single well known destination context, and it's simply a matter of substituting the instruction for the appropriate macro. Signed-off-by:
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Nicholas Piggin authored
commit 50e51c13 upstream. The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is used for switching from the kernel to userspace, and from the hypervisor to the guest kernel. However it can and is also used for other transitions, eg. from real mode kernel code to virtual mode kernel code, and it's not always clear from the code what the destination context is. To make it clearer when reading the code, add macros which encode the expected destination context. Signed-off-by:
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Michael Neuling authored
commit 191eccb1 upstream. A new hypervisor call has been defined to communicate various characteristics of the CPU to guests. Add definitions for the hcall number, flags and a wrapper function. Signed-off-by:
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Simon Ser authored
commit d89e4264 upstream. Fix a seg fault when no parameter is provided to 'objtool orc'. Signed-off-by:
Simon Ser <contact@emersion.fr> Signed-off-by:
Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/9172803ec7ebb72535bcd0b7f966ae96d515968e.1514666459.git.jpoimboe@redhat.comSigned-off-by:
Ingo Molnar <mingo@kernel.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Lukas Bulwahn authored
commit e7e83dd3 upstream. Fix the following Clang enum conversion warning: arch/x86/decode.c:141:20: error: implicit conversion from enumeration type 'enum op_src_type' to different enumeration type 'enum op_dest_type' [-Werror,-Wenum-conversion] op->dest.type = OP_SRC_REG; ~ ^~~~~~~~~~ It just happened to work before because OP_SRC_REG and OP_DEST_REG have the same value. Signed-off-by:
Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by:
Nicholas Mc Guire <der.herr@hofr.at> Reviewed-by:
Nick Desaulniers <nick.desaulniers@gmail.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: baa41469 ("objtool: Implement stack validation 2.0") Link: http://lkml.kernel.org/r/b4156c5738bae781c392e7a3691aed4514ebbdf2.1514323568.git.jpoimboe@redhat.comSigned-off-by:
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Simon Ser authored
commit ce90aaf5 upstream. Fix a seg fault which happens when an input file provided to 'objtool orc generate' doesn't have a '.shstrtab' section (for instance, object files produced by clang don't have this section). Signed-off-by:
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Rob Clark authored
commit 1b5c7ef3 upstream. Fixes broken dp on GF119: Call Trace: ? nvkm_dp_train_drive+0x183/0x2c0 [nouveau] nvkm_dp_acquire+0x4f3/0xcd0 [nouveau] nv50_disp_super_2_2+0x5d/0x470 [nouveau] ? nvkm_devinit_pll_set+0xf/0x20 [nouveau] gf119_disp_super+0x19c/0x2f0 [nouveau] process_one_work+0x193/0x3c0 worker_thread+0x35/0x3b0 kthread+0x125/0x140 ? process_one_work+0x3c0/0x3c0 ? kthread_park+0x60/0x60 ret_from_fork+0x25/0x30 Code: Bad RIP value. RIP: (null) RSP: ffffb1e243e4bc38 CR2: 0000000000000000 Fixes: af85389c drm/nouveau/disp: shuffle functions around Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103421Signed-off-by:
Rob Clark <robdclark@gmail.com> Signed-off-by:
Ben Skeggs <bskeggs@redhat.com> Cc: Sven Joachim <svenjoac@gmx.de> Signed-off-by:
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Andrew Morton authored
commit 0f908ccb upstream. patch(1) loses the x bit. So if a user follows our patching instructions in Documentation/admin-guide/README.rst, their kernel will not compile. Fixes: 3bd51c5a ("objtool: Move kernel headers/code sync check to a script") Reported-by:
Nicolas Bock <nicolasbock@gentoo.org> Reported-by Joakim Tjernlund <Joakim.Tjernlund@infinera.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Cc: Holger Hoffstätte <holger@applied-asynchrony.com> Signed-off-by:
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- 17 Jan, 2018 20 commits
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Greg Kroah-Hartman authored
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Thomas Gleixner authored
commit b8b9ce4b upstream. Remove the compile time warning when CONFIG_RETPOLINE=y and the compiler does not have retpoline support. Linus rationale for this is: It's wrong because it will just make people turn off RETPOLINE, and the asm updates - and return stack clearing - that are independent of the compiler are likely the most important parts because they are likely the ones easiest to target. And it's annoying because most people won't be able to do anything about it. The number of people building their own compiler? Very small. So if their distro hasn't got a compiler yet (and pretty much nobody does), the warning is just annoying crap. It is already properly reported as part of the sysfs interface. The compile-time warning only encourages bad things. Fixes: 76b04384 ("x86/retpoline: Add initial retpoline support") Requested-by:
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Peter Zijlstra authored
commit 99a9dc98 upstream. The intel_bts driver does not use the 'normal' BTS buffer which is exposed through the cpu_entry_area but instead uses the memory allocated for the perf AUX buffer. This obviously comes apart when using PTI because then the kernel mapping; which includes that AUX buffer memory; disappears. Fixing this requires to expose a mapping which is visible in all context and that's not trivial. As a quick fix disable this driver when PTI is enabled to prevent malfunction. Fixes: 385ce0ea ("x86/mm/pti: Add Kconfig") Reported-by:
Vince Weaver <vincent.weaver@maine.edu> Reported-by:
Robert Święcki <robert@swiecki.net> Signed-off-by:
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W. Trevor King authored
commit a237f762 upstream. When the config option for PTI was added a reference to documentation was added as well. But the documentation did not exist at that point. The final documentation has a different file name. Fix it up to point to the proper file. Fixes: 385ce0ea ("x86/mm/pti: Add Kconfig") Signed-off-by:
W. Trevor King <wking@tremily.us> Signed-off-by:
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Thomas Gleixner authored
commit f10ee3dc upstream. The switch to the user space page tables in the low level ASM code sets unconditionally bit 12 and bit 11 of CR3. Bit 12 is switching the base address of the page directory to the user part, bit 11 is switching the PCID to the PCID associated with the user page tables. This fails on a machine which lacks PCID support because bit 11 is set in CR3. Bit 11 is reserved when PCID is inactive. While the Intel SDM claims that the reserved bits are ignored when PCID is disabled, the AMD APM states that they should be cleared. This went unnoticed as the AMD APM was not checked when the code was developed and reviewed and test systems with Intel CPUs never failed to boot. The report is against a Centos 6 host where the guest fails to boot, so it's not yet clear whether this is a virt issue or can happen on real hardware too, but thats irrelevant as the AMD APM clearly ask for clearing the reserved bits. Make sure that on non PCID machines bit 11 is not set by the page table switching code. Andy suggested to rename the related bits and masks so they are clearly describing what they should be used for, which is done as well for clarity. That split could have been done with alternatives but the macro hell is horrible and ugly. This can be done on top if someone cares to remove the extra orq. For now it's a straight forward fix. Fixes: 6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches") Reported-by:
Laura Abbott <labbott@redhat.com> Signed-off-by:
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Andy Lutomirski authored
commit 352909b4 upstream. This tests that the vsyscall entries do what they're expected to do. It also confirms that attempts to read the vsyscall page behave as expected. If changes are made to the vsyscall code or its memory map handling, running this test in all three of vsyscall=none, vsyscall=emulate, and vsyscall=native are helpful. (Because it's easy, this also compares the vsyscall results to their vDSO equivalents.) Note to KAISER backporters: please test this under all three vsyscall modes. Also, in the emulate and native modes, make sure that test_vsyscall_64 agrees with the command line or config option as to which mode you're in. It's quite easy to mess up the kernel such that native mode accidentally emulates or vice versa. Greg, etc: please backport this to all your Meltdown-patched kernels. It'll help make sure the patches didn't regress vsyscalls. CSigned-off-by:
Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/2b9c5a174c1d60fd7774461d518aa75598b1d8fd.1515719552.git.luto@kernel.orgSigned-off-by:
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David Woodhouse authored
commit 117cc7a9 upstream. In accordance with the Intel and AMD documentation, we need to overwrite all entries in the RSB on exiting a guest, to prevent malicious branch target predictions from affecting the host kernel. This is needed both for retpoline and for IBRS. [ak: numbers again for the RSB stuffing labels] Signed-off-by:
David Woodhouse <dwmw@amazon.co.uk> Signed-off-by:
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Andi Kleen authored
commit 7614e913 upstream. Convert all indirect jumps in 32bit irq inline asm code to use non speculative sequences. Signed-off-by:
Andi Kleen <ak@linux.intel.com> Signed-off-by:
Arjan van de Ven <arjan@linux.intel.com> Acked-by:
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David Woodhouse authored
commit 5096732f upstream. Convert all indirect jumps in 32bit checksum assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by:
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David Woodhouse authored
commit ea08816d upstream. Convert indirect call in Xen hypercall to use non-speculative sequence, when CONFIG_RETPOLINE is enabled. Signed-off-by:
Juergen Gross <jgross@suse.com> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-10-git-send-email-dwmw@amazon.co.ukSigned-off-by:
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David Woodhouse authored
commit e70e5892 upstream. Convert all indirect jumps in hyperv inline asm code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by:
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David Woodhouse authored
commit 9351803b upstream. Convert all indirect jumps in ftrace assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by:
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David Woodhouse authored
commit 2641f08b upstream. Convert indirect jumps in core 32/64bit entry assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Don't use CALL_NOSPEC in entry_SYSCALL_64_fastpath because the return address after the 'call' instruction must be *precisely* at the .Lentry_SYSCALL_64_after_fastpath label for stub_ptregs_64 to work, and the use of alternatives will mess that up unless we play horrid games to prepend with NOPs and make the variants the same length. It's not worth it; in the case where we ALTERNATIVE out the retpoline, the first instruction at __x86.indirect_thunk.rax is going to be a bare jmp *%rax anyway. Signed-off-by:
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David Woodhouse authored
commit 9697fa39 upstream. Convert all indirect jumps in crypto assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by:
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David Woodhouse authored
commit da285121 upstream. Add a spectre_v2= option to select the mitigation used for the indirect branch speculation vulnerability. Currently, the only option available is retpoline, in its various forms. This will be expanded to cover the new IBRS/IBPB microcode features. The RETPOLINE_AMD feature relies on a serializing LFENCE for speculation control. For AMD hardware, only set RETPOLINE_AMD if LFENCE is a serializing instruction, which is indicated by the LFENCE_RDTSC feature. [ tglx: Folded back the LFENCE/AMD fixes and reworked it so IBRS integration becomes simple ] Signed-off-by:
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David Woodhouse authored
commit 76b04384 upstream. Enable the use of -mindirect-branch=thunk-extern in newer GCC, and provide the corresponding thunks. Provide assembler macros for invoking the thunks in the same way that GCC does, from native and inline assembler. This adds X86_FEATURE_RETPOLINE and sets it by default on all CPUs. In some circumstances, IBRS microcode features may be used instead, and the retpoline can be disabled. On AMD CPUs if lfence is serialising, the retpoline can be dramatically simplified to a simple "lfence; jmp *\reg". A future patch, after it has been verified that lfence really is serialising in all circumstances, can enable this by setting the X86_FEATURE_RETPOLINE_AMD feature bit in addition to X86_FEATURE_RETPOLINE. Do not align the retpoline in the altinstr section, because there is no guarantee that it stays aligned when it's copied over the oldinstr during alternative patching. [ Andi Kleen: Rename the macros, add CONFIG_RETPOLINE option, export thunks] [ tglx: Put actual function CALL/JMP in front of the macros, convert to symbolic labels ] [ dwmw2: Convert back to numeric labels, merge objtool fixes ] Signed-off-by:
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Josh Poimboeuf authored
commit 258c7605 upstream. Getting objtool to understand retpolines is going to be a bit of a challenge. For now, take advantage of the fact that retpolines are patched in with alternatives. Just read the original (sane) non-alternative instruction, and ignore the patched-in retpoline. This allows objtool to understand the control flow *around* the retpoline, even if it can't yet follow what's inside. This means the ORC unwinder will fail to unwind from inside a retpoline, but will work fine otherwise. Signed-off-by:
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Josh Poimboeuf authored
commit 39b73533 upstream. A direct jump to a retpoline thunk is really an indirect jump in disguise. Change the objtool instruction type accordingly. Objtool needs to know where indirect branches are so it can detect switch statement jump tables. This fixes a bunch of warnings with CONFIG_RETPOLINE like: arch/x86/events/intel/uncore_nhmex.o: warning: objtool: nhmex_rbox_msr_enable_event()+0x44: sibling call from callable instruction with modified stack frame kernel/signal.o: warning: objtool: copy_siginfo_to_user()+0x91: sibling call from callable instruction with modified stack frame ... Signed-off-by:
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Dave Hansen authored
commit 445b69e3 upstream. The inital fix for trusted boot and PTI potentially misses the pgd clearing if pud_alloc() sets a PGD. It probably works in *practice* because for two adjacent calls to map_tboot_page() that share a PGD entry, the first will clear NX, *then* allocate and set the PGD (without NX clear). The second call will *not* allocate but will clear the NX bit. Defer the NX clearing to a point after it is known that all top-level allocations have occurred. Add a comment to clarify why. [ tglx: Massaged changelog ] Fixes: 262b6b30 ("x86/tboot: Unbreak tboot with PTI enabled") Signed-off-by:
Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by:
Andrea Arcangeli <aarcange@redhat.com> Cc: Jon Masters <jcm@redhat.com> Cc: "Tim Chen" <tim.c.chen@linux.intel.com> Cc: gnomes@lxorguk.ukuu.org.uk Cc: peterz@infradead.org Cc: ning.sun@intel.com Cc: tboot-devel@lists.sourceforge.net Cc: andi@firstfloor.org Cc: luto@kernel.org Cc: law@redhat.com Cc: pbonzini@redhat.com Cc: torvalds@linux-foundation.org Cc: gregkh@linux-foundation.org Cc: dwmw@amazon.co.uk Cc: nickc@redhat.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180110224939.2695CD47@viggo.jf.intel.comSigned-off-by:
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Borislav Petkov authored
commit 612e8e93 upstream. The alternatives code checks only the first byte whether it is a NOP, but with NOPs in front of the payload and having actual instructions after it breaks the "optimized' test. Make sure to scan all bytes before deciding to optimize the NOPs in there. Reported-by:
David Woodhouse <dwmw2@infradead.org> Signed-off-by:
Borislav Petkov <bp@suse.de> Signed-off-by:
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