Commit Graph

984262 Commits

Author SHA1 Message Date
Jakub Kicinski
672fac0a43 net: inline rollback_registered()
commit 037e56bd965e1bc72c2fa9684ac25b56839a338e upstream.

rollback_registered() is a local helper, it's common for driver
code to call unregister_netdevice_queue(dev, NULL) when they
want to unregister netdevices under rtnl_lock. Inline
rollback_registered() and adjust the only remaining caller.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:08 +02:00
Jakub Kicinski
b1158677d4 net: move net_set_todo inside rollback_registered()
commit 2014beea7eb165c745706b13659a0f1d0a9a2a61 upstream.

Commit 93ee31f14f ("[NET]: Fix free_netdev on register_netdev
failure.") moved net_set_todo() outside of rollback_registered()
so that rollback_registered() can be used in the failure path of
register_netdevice() but without risking a double free.

Since commit cf124db566 ("net: Fix inconsistent teardown and
release of private netdev state."), however, we have a better
way of handling that condition, since destructors don't call
free_netdev() directly.

After the change in commit c269a24ce057 ("net: make free_netdev()
more lenient with unregistering devices") we can now move
net_set_todo() back.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:08 +02:00
Jakub Kicinski
2e11856ec3 net: make sure devices go through netdev_wait_all_refs
commit 766b0515d5bec4b780750773ed3009b148df8c0a upstream.

If register_netdevice() fails at the very last stage - the
notifier call - some subsystems may have already seen it and
grabbed a reference. struct net_device can't be freed right
away without calling netdev_wait_all_refs().

Now that we have a clean interface in form of dev->needs_free_netdev
and lenient free_netdev() we can undo what commit 93ee31f14f ("[NET]:
Fix free_netdev on register_netdev failure.") has done and complete
the unregistration path by bringing the net_set_todo() call back.

After registration fails user is still expected to explicitly
free the net_device, so make sure ->needs_free_netdev is cleared,
otherwise rolling back the registration will cause the old double
free for callers who release rtnl_lock before the free.

This also solves the problem of priv_destructor not being called
on notifier error.

net_set_todo() will be moved back into unregister_netdevice_queue()
in a follow up.

Reported-by: Hulk Robot <hulkci@huawei.com>
Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:08 +02:00
Jakub Kicinski
ed6964ff47 net: make free_netdev() more lenient with unregistering devices
commit c269a24ce057abfc31130960e96ab197ef6ab196 upstream.

There are two flavors of handling netdev registration:
 - ones called without holding rtnl_lock: register_netdev() and
   unregister_netdev(); and
 - those called with rtnl_lock held: register_netdevice() and
   unregister_netdevice().

While the semantics of the former are pretty clear, the same can't
be said about the latter. The netdev_todo mechanism is utilized to
perform some of the device unregistering tasks and it hooks into
rtnl_unlock() so the locked variants can't actually finish the work.
In general free_netdev() does not mix well with locked calls. Most
drivers operating under rtnl_lock set dev->needs_free_netdev to true
and expect core to make the free_netdev() call some time later.

The part where this becomes most problematic is error paths. There is
no way to unwind the state cleanly after a call to register_netdevice(),
since unreg can't be performed fully without dropping locks.

Make free_netdev() more lenient, and defer the freeing if device
is being unregistered. This allows error paths to simply call
free_netdev() both after register_netdevice() failed, and after
a call to unregister_netdevice() but before dropping rtnl_lock.

Simplify the error paths which are currently doing gymnastics
around free_netdev() handling.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:07 +02:00
Jakub Kicinski
2686f62fa7 docs: net: explain struct net_device lifetime
commit 2b446e650b418f9a9e75f99852e2f2560cabfa17 upstream.

Explain the two basic flows of struct net_device's operation.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:07 +02:00
Demi Marie Obenour
7a99c7c32c xen/gntdev: Ignore failure to unmap INVALID_GRANT_HANDLE
commit 166d3863231667c4f64dee72b77d1102cdfad11f upstream.

The error paths of gntdev_mmap() can call unmap_grant_pages() even
though not all of the pages have been successfully mapped.  This will
trigger the WARN_ON()s in __unmap_grant_pages_done().  The number of
warnings can be very large; I have observed thousands of lines of
warnings in the systemd journal.

Avoid this problem by only warning on unmapping failure if the handle
being unmapped is not INVALID_GRANT_HANDLE.  The handle field of any
page that was not successfully mapped will be INVALID_GRANT_HANDLE, so
this catches all cases where unmapping can legitimately fail.

Fixes: dbe97cff7dd9 ("xen/gntdev: Avoid blocking in unmap_grant_pages()")
Cc: stable@vger.kernel.org
Suggested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220710230522.1563-1-demi@invisiblethingslab.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:07 +02:00
Lee Jones
2ee0cab11f io_uring: Use original task for req identity in io_identity_cow()
This issue is conceptually identical to the one fixed in 29f077d070
("io_uring: always use original task when preparing req identity"), so
rather than reinvent the wheel, I'm shamelessly quoting the commit
message from that patch - thanks Jens:

 "If the ring is setup with IORING_SETUP_IOPOLL and we have more than
  one task doing submissions on a ring, we can up in a situation where
  we assign the context from the current task rather than the request
  originator.

  Always use req->task rather than assume it's the same as current.

  No upstream patch exists for this issue, as only older kernels with
  the non-native workers have this problem."

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: io-uring@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Fixes: 5c3462cfd1 ("io_uring: store io_identity in io_uring_task")
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:07 +02:00
Eric Snowberg
ab5050fd74 lockdown: Fix kexec lockdown bypass with ima policy
commit 543ce63b664e2c2f9533d089a4664b559c3e6b5b upstream.

The lockdown LSM is primarily used in conjunction with UEFI Secure Boot.
This LSM may also be used on machines without UEFI.  It can also be
enabled when UEFI Secure Boot is disabled.  One of lockdown's features
is to prevent kexec from loading untrusted kernels.  Lockdown can be
enabled through a bootparam or after the kernel has booted through
securityfs.

If IMA appraisal is used with the "ima_appraise=log" boot param,
lockdown can be defeated with kexec on any machine when Secure Boot is
disabled or unavailable.  IMA prevents setting "ima_appraise=log" from
the boot param when Secure Boot is enabled, but this does not cover
cases where lockdown is used without Secure Boot.

To defeat lockdown, boot without Secure Boot and add ima_appraise=log to
the kernel command line; then:

  $ echo "integrity" > /sys/kernel/security/lockdown
  $ echo "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig" > \
    /sys/kernel/security/ima/policy
  $ kexec -ls unsigned-kernel

Add a call to verify ima appraisal is set to "enforce" whenever lockdown
is enabled.  This fixes CVE-2022-21505.

Cc: stable@vger.kernel.org
Fixes: 29d3c1c8df ("kexec: Allow kexec_file() with appropriate IMA policy when locked down")
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: John Haxby <john.haxby@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:06 +02:00
Ido Schimmel
426336de35 mlxsw: spectrum_router: Fix IPv4 nexthop gateway indication
commit e5ec6a2513383fe2ecc2ee3b5f51d97acbbcd4d8 upstream.

mlxsw needs to distinguish nexthops with a gateway from connected
nexthops in order to write the former to the adjacency table of the
device. The check used to rely on the fact that nexthops with a gateway
have a 'link' scope whereas connected nexthops have a 'host' scope. This
is no longer correct after commit 747c14307214 ("ip: fix dflt addr
selection for connected nexthop").

Fix that by instead checking the address family of the gateway IP. This
is a more direct way and also consistent with the IPv6 counterpart in
mlxsw_sp_rt6_is_gateway().

Cc: stable@vger.kernel.org
Fixes: 747c14307214 ("ip: fix dflt addr selection for connected nexthop")
Fixes: 597cfe4fc3 ("nexthop: Add support for IPv4 nexthops")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:06 +02:00
Ben Dooks
15155fa898 riscv: add as-options for modules with assembly compontents
commit c1f6eff304e4dfa4558b6a8c6b2d26a91db6c998 upstream.

When trying to load modules built for RISC-V which include assembly files
the kernel loader errors with "unexpected relocation type 'R_RISCV_ALIGN'"
due to R_RISCV_ALIGN relocations being generated by the assembler.

The R_RISCV_ALIGN relocations can be removed at the expense of code space
by adding -mno-relax to gcc and as.  In commit 7a8e7da422
("RISC-V: Fixes to module loading") -mno-relax is added to the build
variable KBUILD_CFLAGS_MODULE. See [1] for more info.

The issue is that when kbuild builds a .S file, it invokes gcc with
the -mno-relax flag, but this is not being passed through to the
assembler. Adding -Wa,-mno-relax to KBUILD_AFLAGS_MODULE ensures that
the assembler is invoked correctly. This may have now been fixed in
gcc[2] and this addition should not stop newer gcc and as from working.

[1] https://github.com/riscv/riscv-elf-psabi-doc/issues/183
[2] 3b0a7d624e

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Link: https://lore.kernel.org/r/20220529152200.609809-1-ben.dooks@codethink.co.uk
Fixes: ab1ef68e54 ("RISC-V: Add sections of PLT and GOT for kernel module")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:06 +02:00
Fabien Dessenne
31f3bb363a pinctrl: stm32: fix optional IRQ support to gpios
commit a1d4ef1adf8bbd302067534ead671a94759687ed upstream.

To act as an interrupt controller, a gpio bank relies on the
"interrupt-parent" of the pin controller.
When this optional "interrupt-parent" misses, do not create any IRQ domain.

This fixes a "NULL pointer in stm32_gpio_domain_alloc()" kernel crash when
the interrupt-parent = <exti> property is not declared in the Device Tree.

Fixes: 0eb9f68333 ("pinctrl: Add IRQ support to STM32 gpios")
Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Link: https://lore.kernel.org/r/20220627142350.742973-1-fabien.dessenne@foss.st.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:19:06 +02:00
Greg Kroah-Hartman
5034934536 Linux 5.10.133
Link: https://lore.kernel.org/r/20220723095224.302504400@linuxfoundation.org
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Rudi Heitbaum <rudi@heitbaum.com>
Tested-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:57 +02:00
Arnaldo Carvalho de Melo
2fc7f18ba2 tools headers: Remove broken definition of __LITTLE_ENDIAN
commit fa2c02e5798c17c89cbb3135940086ebe07e5c9f upstream.

The linux/kconfig.h file was copied from the kernel but the line where
with the generated/autoconf.h include from where the CONFIG_ entries
would come from was deleted, as tools/ build system don't create that
file, so we ended up always defining just __LITTLE_ENDIAN as
CONFIG_CPU_BIG_ENDIAN was nowhere to be found.

This in turn ended up breaking the build in some systems where
__LITTLE_ENDIAN was already defined, such as the androind NDK.

So just ditch that block that depends on the CONFIG_CPU_BIG_ENDIAN
define.

The kconfig.h file was copied just to get IS_ENABLED() and a
'make -C tools/all' doesn't breaks with this removal.

Fixes: 93281c4a96572a34 ("x86/insn: Add an insn_decode() API")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/YO8hK7lqJcIWuBzx@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:56 +02:00
Arnaldo Carvalho de Melo
060e39b8c2 tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy' - again
commit fb24e308b6310541e70d11a3f19dc40742974b95 upstream.

To bring in the change made in this cset:

 5e21a3ecad1500e3 ("x86/alternative: Merge include files")

This just silences these perf tools build warnings, no change in the tools:

  Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
  diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
  Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S'
  diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

Cc: Borislav Petkov <bp@suse.de>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:56 +02:00
Vasily Gorbik
fbf60f83e2 objtool: Fix elf_create_undef_symbol() endianness
commit 46c7405df7de8deb97229eacebcee96d61415f3f upstream.

Currently x86 cross-compilation fails on big endian system with:

  x86_64-cross-ld: init/main.o: invalid string offset 488112128 >= 6229 for section `.strtab'

Mark new ELF data in elf_create_undef_symbol() as symbol, so that libelf
does endianness handling correctly.

Fixes: 2f2f7e47f052 ("objtool: Add elf_create_undef_symbol()")
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/patch-1.thread-6c9df9.git-d39264656387.your-ad-here.call-01620841104-ext-2554@work.hours
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:56 +02:00
Linus Torvalds
39065d5434 kvm: fix objtool relocation warning
commit 291073a566b2094c7192872cc0f17ce73d83cb76 upstream.

The recent change to make objtool aware of more symbol relocation types
(commit 24ff65257375: "objtool: Teach get_alt_entry() about more
relocation types") also added another check, and resulted in this
objtool warning when building kvm on x86:

    arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception

The reason seems to be that kvm_fastop_exception() is marked as a global
symbol, which causes the relocation to ke kept around for objtool.  And
at the same time, the kvm_fastop_exception definition (which is done as
an inline asm statement) doesn't actually set the type of the global,
which then makes objtool unhappy.

The minimal fix is to just not mark kvm_fastop_exception as being a
global symbol.  It's only used in that one compilation unit anyway, so
it was always pointless.  That's how all the other local exception table
labels are done.

I'm not entirely happy about the kinds of games that the kvm code plays
with doing its own exception handling, and the fact that it confused
objtool is most definitely a symptom of the code being a bit too subtle
and ad-hoc.  But at least this trivial one-liner makes objtool no longer
upset about what is going on.

Fixes: 24ff65257375 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Cc: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:55 +02:00
Peter Zijlstra
6849ed81a3 x86: Use -mindirect-branch-cs-prefix for RETPOLINE builds
commit 68cf4f2a72ef8786e6b7af6fd9a89f27ac0f520d upstream.

In order to further enable commit:

  bbe2df3f6b6d ("x86/alternative: Try inline spectre_v2=retpoline,amd")

add the new GCC flag -mindirect-branch-cs-prefix:

  https://gcc.gnu.org/g:2196a681d7810ad8b227bf983f38ba716620545e
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952
  https://bugs.llvm.org/show_bug.cgi?id=52323

to RETPOLINE=y builds. This should allow fully inlining retpoline,amd
for GCC builds.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/20211119165630.276205624@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:55 +02:00
Peter Zijlstra
8e2774270a um: Add missing apply_returns()
commit 564d998106397394b6aad260f219b882b3347e62 upstream.

Implement apply_returns() stub for UM, just like all the other patching
routines.

Fixes: 15e67227c49a ("x86: Undo return-thunk damage")
Reported-by: Randy Dunlap <rdunlap@infradead.org)
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/Ys%2Ft45l%2FgarIrD0u@worktop.programming.kicks-ass.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:55 +02:00
Kim Phillips
725da3e67c x86/bugs: Remove apostrophe typo
commit bcf163150cd37348a0cb59e95c916a83a9344b0e upstream.

Remove a superfluous ' in the mitigation string.

Fixes: e8ec1b6e08a2 ("x86/bugs: Enable STIBP for JMP2RET")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:55 +02:00
Arnaldo Carvalho de Melo
81604506c2 tools headers cpufeatures: Sync with the kernel sources
commit f098addbdb44c8a565367f5162f3ab170ed9404a upstream.

To pick the changes from:

  f43b9876e857c739 ("x86/retbleed: Add fine grained Kconfig knobs")
  a149180fbcf336e9 ("x86: Add magic AMD return-thunk")
  15e67227c49a5783 ("x86: Undo return-thunk damage")
  369ae6ffc41a3c11 ("x86/retpoline: Cleanup some #ifdefery")
  4ad3278df6fe2b08 x86/speculation: Disable RRSBA behavior
  26aae8ccbc197223 x86/cpu/amd: Enumerate BTC_NO
  9756bba28470722d x86/speculation: Fill RSB on vmexit for IBRS
  3ebc170068885b6f x86/bugs: Add retbleed=ibpb
  2dbb887e875b1de3 x86/entry: Add kernel IBRS implementation
  6b80b59b35557065 x86/bugs: Report AMD retbleed vulnerability
  a149180fbcf336e9 x86: Add magic AMD return-thunk
  15e67227c49a5783 x86: Undo return-thunk damage
  a883d624aed463c8 x86/cpufeatures: Move RETPOLINE flags to word 11
  51802186158c74a0 x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug

This only causes these perf files to be rebuilt:

  CC       /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o
  CC       /tmp/build/perf/bench/mem-memset-x86-64-asm.o

And addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
  diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/disabled-features.h' differs from latest version at 'arch/x86/include/asm/disabled-features.h'
  diff -u tools/arch/x86/include/asm/disabled-features.h arch/x86/include/asm/disabled-features.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org
Link: https://lore.kernel.org/lkml/YtQM40VmiLTkPND2@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:54 +02:00
Arnaldo Carvalho de Melo
3f93b8630a tools arch x86: Sync the msr-index.h copy with the kernel sources
commit 91d248c3b903b46a58cbc7e8d38d684d3e4007c2 upstream.

To pick up the changes from these csets:

  4ad3278df6fe2b08 ("x86/speculation: Disable RRSBA behavior")
  d7caac991feeef1b ("x86/cpu/amd: Add Spectral Chicken")

That cause no changes to tooling:

  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > before
  $ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > after
  $ diff -u before after
  $

Just silences this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'
  diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/YtQTm9wsB3hxQWvy@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:54 +02:00
Paolo Bonzini
2ef1b06cea KVM: emulate: do not adjust size of fastop and setcc subroutines
commit 79629181607e801c0b41b8790ac4ee2eb5d7bc3e upstream.

Instead of doing complicated calculations to find the size of the subroutines
(which are even more complicated because they need to be stringified into
an asm statement), just hardcode to 16.

It is less dense for a few combinations of IBT/SLS/retbleed, but it has
the advantage of being really simple.

Cc: stable@vger.kernel.org # 5.15.x: 84e7051c0bc1: x86/kvm: fix FASTOP_SIZE when return thunks are enabled
Cc: stable@vger.kernel.org
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:54 +02:00
Thadeu Lima de Souza Cascardo
8e31dfd630 x86/kvm: fix FASTOP_SIZE when return thunks are enabled
commit 84e7051c0bc1f2a13101553959b3a9d9a8e24939 upstream.

The return thunk call makes the fastop functions larger, just like IBT
does. Consider a 16-byte FASTOP_SIZE when CONFIG_RETHUNK is enabled.

Otherwise, functions will be incorrectly aligned and when computing their
position for differently sized operators, they will executed in the middle
or end of a function, which may as well be an int3, leading to a crash
like:

[   36.091116] int3: 0000 [#1] SMP NOPTI
[   36.091119] CPU: 3 PID: 1371 Comm: qemu-system-x86 Not tainted 5.15.0-41-generic #44
[   36.091120] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
[   36.091121] RIP: 0010:xaddw_ax_dx+0x9/0x10 [kvm]
[   36.091185] Code: 00 0f bb d0 c3 cc cc cc cc 48 0f bb d0 c3 cc cc cc cc 0f 1f 80 00 00 00 00 0f c0 d0 c3 cc cc cc cc 66 0f c1 d0 c3 cc cc cc cc <0f> 1f 80 00 00 00 00 0f c1 d0 c3 cc cc cc cc 48 0f c1 d0 c3 cc cc
[   36.091186] RSP: 0018:ffffb1f541143c98 EFLAGS: 00000202
[   36.091188] RAX: 0000000089abcdef RBX: 0000000000000001 RCX: 0000000000000000
[   36.091188] RDX: 0000000076543210 RSI: ffffffffc073c6d0 RDI: 0000000000000200
[   36.091189] RBP: ffffb1f541143ca0 R08: ffff9f1803350a70 R09: 0000000000000002
[   36.091190] R10: ffff9f1803350a70 R11: 0000000000000000 R12: ffff9f1803350a70
[   36.091190] R13: ffffffffc077fee0 R14: 0000000000000000 R15: 0000000000000000
[   36.091191] FS:  00007efdfce8d640(0000) GS:ffff9f187dd80000(0000) knlGS:0000000000000000
[   36.091192] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   36.091192] CR2: 0000000000000000 CR3: 0000000009b62002 CR4: 0000000000772ee0
[   36.091195] PKRU: 55555554
[   36.091195] Call Trace:
[   36.091197]  <TASK>
[   36.091198]  ? fastop+0x5a/0xa0 [kvm]
[   36.091222]  x86_emulate_insn+0x7b8/0xe90 [kvm]
[   36.091244]  x86_emulate_instruction+0x2f4/0x630 [kvm]
[   36.091263]  ? kvm_arch_vcpu_load+0x7c/0x230 [kvm]
[   36.091283]  ? vmx_prepare_switch_to_host+0xf7/0x190 [kvm_intel]
[   36.091290]  complete_emulated_mmio+0x297/0x320 [kvm]
[   36.091310]  kvm_arch_vcpu_ioctl_run+0x32f/0x550 [kvm]
[   36.091330]  kvm_vcpu_ioctl+0x29e/0x6d0 [kvm]
[   36.091344]  ? kvm_vcpu_ioctl+0x120/0x6d0 [kvm]
[   36.091357]  ? __fget_files+0x86/0xc0
[   36.091362]  ? __fget_files+0x86/0xc0
[   36.091363]  __x64_sys_ioctl+0x92/0xd0
[   36.091366]  do_syscall_64+0x59/0xc0
[   36.091369]  ? syscall_exit_to_user_mode+0x27/0x50
[   36.091370]  ? do_syscall_64+0x69/0xc0
[   36.091371]  ? syscall_exit_to_user_mode+0x27/0x50
[   36.091372]  ? __x64_sys_writev+0x1c/0x30
[   36.091374]  ? do_syscall_64+0x69/0xc0
[   36.091374]  ? exit_to_user_mode_prepare+0x37/0xb0
[   36.091378]  ? syscall_exit_to_user_mode+0x27/0x50
[   36.091379]  ? do_syscall_64+0x69/0xc0
[   36.091379]  ? do_syscall_64+0x69/0xc0
[   36.091380]  ? do_syscall_64+0x69/0xc0
[   36.091381]  ? do_syscall_64+0x69/0xc0
[   36.091381]  entry_SYSCALL_64_after_hwframe+0x61/0xcb
[   36.091384] RIP: 0033:0x7efdfe6d1aff
[   36.091390] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 77 1f 48 8b 44 24 18 64 48 2b 04 25 28 00
[   36.091391] RSP: 002b:00007efdfce8c460 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[   36.091393] RAX: ffffffffffffffda RBX: 000000000000ae80 RCX: 00007efdfe6d1aff
[   36.091393] RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 000000000000000c
[   36.091394] RBP: 0000558f1609e220 R08: 0000558f13fb8190 R09: 00000000ffffffff
[   36.091394] R10: 0000558f16b5e950 R11: 0000000000000246 R12: 0000000000000000
[   36.091394] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
[   36.091396]  </TASK>
[   36.091397] Modules linked in: isofs nls_iso8859_1 kvm_intel joydev kvm input_leds serio_raw sch_fq_codel dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua ipmi_devintf ipmi_msghandler drm msr ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel virtio_net net_failover crypto_simd ahci xhci_pci cryptd psmouse virtio_blk libahci xhci_pci_renesas failover
[   36.123271] ---[ end trace db3c0ab5a48fabcc ]---
[   36.123272] RIP: 0010:xaddw_ax_dx+0x9/0x10 [kvm]
[   36.123319] Code: 00 0f bb d0 c3 cc cc cc cc 48 0f bb d0 c3 cc cc cc cc 0f 1f 80 00 00 00 00 0f c0 d0 c3 cc cc cc cc 66 0f c1 d0 c3 cc cc cc cc <0f> 1f 80 00 00 00 00 0f c1 d0 c3 cc cc cc cc 48 0f c1 d0 c3 cc cc
[   36.123320] RSP: 0018:ffffb1f541143c98 EFLAGS: 00000202
[   36.123321] RAX: 0000000089abcdef RBX: 0000000000000001 RCX: 0000000000000000
[   36.123321] RDX: 0000000076543210 RSI: ffffffffc073c6d0 RDI: 0000000000000200
[   36.123322] RBP: ffffb1f541143ca0 R08: ffff9f1803350a70 R09: 0000000000000002
[   36.123322] R10: ffff9f1803350a70 R11: 0000000000000000 R12: ffff9f1803350a70
[   36.123323] R13: ffffffffc077fee0 R14: 0000000000000000 R15: 0000000000000000
[   36.123323] FS:  00007efdfce8d640(0000) GS:ffff9f187dd80000(0000) knlGS:0000000000000000
[   36.123324] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   36.123325] CR2: 0000000000000000 CR3: 0000000009b62002 CR4: 0000000000772ee0
[   36.123327] PKRU: 55555554
[   36.123328] Kernel panic - not syncing: Fatal exception in interrupt
[   36.123410] Kernel Offset: 0x1400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   36.135305] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Fixes: aa3d480315ba ("x86: Use return-thunk in asm code")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Message-Id: <20220713171241.184026-1-cascardo@canonical.com>
Tested-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:54 +02:00
Thadeu Lima de Souza Cascardo
5779e2f0cc efi/x86: use naked RET on mixed mode call wrapper
commit 51a6fa0732d6be6a44e0032752ad2ac10d67c796 upstream.

When running with return thunks enabled under 32-bit EFI, the system
crashes with:

  kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
  BUG: unable to handle page fault for address: 000000005bc02900
  #PF: supervisor instruction fetch in kernel mode
  #PF: error_code(0x0011) - permissions violation
  PGD 18f7063 P4D 18f7063 PUD 18ff063 PMD 190e063 PTE 800000005bc02063
  Oops: 0011 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc6+ #166
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:0x5bc02900
  Code: Unable to access opcode bytes at RIP 0x5bc028d6.
  RSP: 0018:ffffffffb3203e10 EFLAGS: 00010046
  RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000048
  RDX: 000000000190dfac RSI: 0000000000001710 RDI: 000000007eae823b
  RBP: ffffffffb3203e70 R08: 0000000001970000 R09: ffffffffb3203e28
  R10: 747563657865206c R11: 6c6977203a696665 R12: 0000000000001710
  R13: 0000000000000030 R14: 0000000001970000 R15: 0000000000000001
  FS:  0000000000000000(0000) GS:ffff8e013ca00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0018 ES: 0018 CR0: 0000000080050033
  CR2: 000000005bc02900 CR3: 0000000001930000 CR4: 00000000000006f0
  Call Trace:
   ? efi_set_virtual_address_map+0x9c/0x175
   efi_enter_virtual_mode+0x4a6/0x53e
   start_kernel+0x67c/0x71e
   x86_64_start_reservations+0x24/0x2a
   x86_64_start_kernel+0xe9/0xf4
   secondary_startup_64_no_verify+0xe5/0xeb

That's because it cannot jump to the return thunk from the 32-bit code.

Using a naked RET and marking it as safe allows the system to proceed
booting.

Fixes: aa3d480315ba ("x86: Use return-thunk in asm code")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: <stable@vger.kernel.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:53 +02:00
Nathan Chancellor
abf88ff134 x86/speculation: Use DECLARE_PER_CPU for x86_spec_ctrl_current
commit db886979683a8360ced9b24ab1125ad0c4d2cf76 upstream.

Clang warns:

  arch/x86/kernel/cpu/bugs.c:58:21: error: section attribute is specified on redeclared variable [-Werror,-Wsection]
  DEFINE_PER_CPU(u64, x86_spec_ctrl_current);
                      ^
  arch/x86/include/asm/nospec-branch.h:283:12: note: previous declaration is here
  extern u64 x86_spec_ctrl_current;
             ^
  1 error generated.

The declaration should be using DECLARE_PER_CPU instead so all
attributes stay in sync.

Cc: stable@vger.kernel.org
Fixes: fc02735b14ff ("KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:53 +02:00
Jiri Slaby
ecc0d92a9f x86/asm/32: Fix ANNOTATE_UNRET_SAFE use on 32-bit
commit 3131ef39fb03bbde237d0b8260445898f3dfda5b upstream.

The build on x86_32 currently fails after commit

  9bb2ec608a20 (objtool: Update Retpoline validation)

with:

  arch/x86/kernel/../../x86/xen/xen-head.S:35: Error: no such instruction: `annotate_unret_safe'

ANNOTATE_UNRET_SAFE is defined in nospec-branch.h. And head_32.S is
missing this include. Fix this.

Fixes: 9bb2ec608a20 ("objtool: Update Retpoline validation")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/63e23f80-033f-f64e-7522-2816debbc367@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:53 +02:00
Josh Poimboeuf
95d89ec7db x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub
commit 18660698a3d30868524cefb60dcd4e0e297f71bb upstream.

Prevent an unreachable objtool warning after the sibling call detection
gets improved.  ftrace_stub() is basically a function, annotate it as
such.

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/6845e1b2fb0723a95740c6674e548ba38c5ea489.1611263461.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:52 +02:00
Ben Hutchings
668cb1ddf0 x86/xen: Fix initialisation in hypercall_page after rethunk
The hypercall_page is special and the RETs there should not be changed
into rethunk calls (but can have SLS mitigation).  Change the initial
instructions to ret + int3 padding, as was done in upstream commit
5b2fc51576ef "x86/ibt,xen: Sprinkle the ENDBR".

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:52 +02:00
Greg Kroah-Hartman
81f20e5000 x86, kvm: use proper ASM macros for kvm_vcpu_is_preempted
commit edbaf6e5e93acda96aae23ba134ef3c1466da3b5 upstream.

The build rightfully complains about:
	arch/x86/kernel/kvm.o: warning: objtool: __raw_callee_save___kvm_vcpu_is_preempted()+0x12: missing int3 after ret

because the ASM_RET call is not being used correctly in kvm_vcpu_is_preempted().

This was hand-fixed-up in the kvm merge commit a4cfff3f0f8c ("Merge branch
'kvm-older-features' into HEAD") which of course can not be backported to
stable kernels, so just fix this up directly instead.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ben Hutchings <bwh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:52 +02:00
Borislav Petkov
844947eee3 tools/insn: Restore the relative include paths for cross building
commit 0705ef64d1ff52b817e278ca6e28095585ff31e1 upstream.

Building perf on ppc causes:

  In file included from util/intel-pt-decoder/intel-pt-insn-decoder.c:15:
  util/intel-pt-decoder/../../../arch/x86/lib/insn.c:14:10: fatal error: asm/inat.h: No such file or directory
     14 | #include <asm/inat.h> /*__ignore_sync_check__ */
        |          ^~~~~~~~~~~~

Restore the relative include paths so that the compiler can find the
headers.

Fixes: 93281c4a9657 ("x86/insn: Add an insn_decode() API")
Reported-by: Ian Rogers <irogers@google.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Ian Rogers <irogers@google.com>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/20210317150858.02b1bbc8@canb.auug.org.au
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:52 +02:00
Thomas Gleixner
c035ca88b0 x86/static_call: Serialize __static_call_fixup() properly
commit c27c753ea6fd1237f4f96abf8b623d7bab505513 upstream.

__static_call_fixup() invokes __static_call_transform() without holding
text_mutex, which causes lockdep to complain in text_poke_bp().

Adding the proper locking cures that, but as this is either used during
early boot or during module finalizing, it's not required to use
text_poke_bp(). Add an argument to __static_call_transform() which tells
it to use text_poke_early() for it.

Fixes: ee88d363d156 ("x86,static_call: Use alternative RET encoding")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:51 +02:00
Pawan Gupta
eb38964b6f x86/speculation: Disable RRSBA behavior
commit 4ad3278df6fe2b0852b00d5757fc2ccd8e92c26e upstream.

Some Intel processors may use alternate predictors for RETs on
RSB-underflow. This condition may be vulnerable to Branch History
Injection (BHI) and intramode-BTI.

Kernel earlier added spectre_v2 mitigation modes (eIBRS+Retpolines,
eIBRS+LFENCE, Retpolines) which protect indirect CALLs and JMPs against
such attacks. However, on RSB-underflow, RET target prediction may
fallback to alternate predictors. As a result, RET's predicted target
may get influenced by branch history.

A new MSR_IA32_SPEC_CTRL bit (RRSBA_DIS_S) controls this fallback
behavior when in kernel mode. When set, RETs will not take predictions
from alternate predictors, hence mitigating RETs as well. Support for
this is enumerated by CPUID.7.2.EDX[RRSBA_CTRL] (bit2).

For spectre v2 mitigation, when a user selects a mitigation that
protects indirect CALLs and JMPs against BHI and intramode-BTI, set
RRSBA_DIS_S also to protect RETs for RSB-underflow case.

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
[bwh: Backported to 5.15: adjust context in scattered.c]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:51 +02:00
Konrad Rzeszutek Wilk
c2ca992144 x86/kexec: Disable RET on kexec
commit 697977d8415d61f3acbc4ee6d564c9dcf0309507 upstream.

All the invocations unroll to __x86_return_thunk and this file
must be PIC independent.

This fixes kexec on 64-bit AMD boxes.

  [ bp: Fix 32-bit build. ]

Reported-by: Edward Tran <edward.tran@oracle.com>
Reported-by: Awais Tanveer <awais.tanveer@oracle.com>
Suggested-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:51 +02:00
Thadeu Lima de Souza Cascardo
51552b6b52 x86/bugs: Do not enable IBPB-on-entry when IBPB is not supported
commit 2259da159fbe5dba8ac00b560cf00b6a6537fa18 upstream.

There are some VM configurations which have Skylake model but do not
support IBPB. In those cases, when using retbleed=ibpb, userspace is going
to be killed and kernel is going to panic.

If the CPU does not support IBPB, warn and proceed with the auto option. Also,
do not fallback to IBPB on AMD/Hygon systems if it is not supported.

Fixes: 3ebc17006888 ("x86/bugs: Add retbleed=ibpb")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:50 +02:00
Pawan Gupta
609336351d x86/bugs: Add Cannon lake to RETBleed affected CPU list
commit f54d45372c6ac9c993451de5e51312485f7d10bc upstream.

Cannon lake is also affected by RETBleed, add it to the list.

Fixes: 6ad0ad2bf8a6 ("x86/bugs: Report Intel retbleed vulnerability")
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:50 +02:00
Peter Zijlstra
b24fdd0f1c x86/retbleed: Add fine grained Kconfig knobs
commit f43b9876e857c739d407bc56df288b0ebe1a9164 upstream.

Do fine-grained Kconfig for all the various retbleed parts.

NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
[cascardo: there is no CONFIG_OBJTOOL]
[cascardo: objtool calling and option parsing has changed]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
[bwh: Backported to 5.10:
 - In scripts/Makefile.build, add the objtool option with an ifdef
   block, same as for other options
 - Adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:50 +02:00
Andrew Cooper
f7851ed697 x86/cpu/amd: Enumerate BTC_NO
commit 26aae8ccbc1972233afd08fb3f368947c0314265 upstream.

BTC_NO indicates that hardware is not susceptible to Branch Type Confusion.

Zen3 CPUs don't suffer BTC.

Hypervisors are expected to synthesise BTC_NO when it is appropriate
given the migration pool, to prevent kernels using heuristics.

  [ bp: Massage. ]

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
[cascardo: no X86_FEATURE_BRS]
[cascardo: no X86_FEATURE_CPPC]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:49 +02:00
Peter Zijlstra
a74f5d23e6 x86/common: Stamp out the stepping madness
commit 7a05bc95ed1c5a59e47aaade9fb4083c27de9e62 upstream.

The whole MMIO/RETBLEED enumeration went overboard on steppings. Get
rid of all that and simply use ANY.

If a future stepping of these models would not be affected, it had
better set the relevant ARCH_CAP_$FOO_NO bit in
IA32_ARCH_CAPABILITIES.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:49 +02:00
Josh Poimboeuf
4d7f72b6e1 x86/speculation: Fill RSB on vmexit for IBRS
commit 9756bba28470722dacb79ffce554336dd1f6a6cd upstream.

Prevent RSB underflow/poisoning attacks with RSB.  While at it, add a
bunch of comments to attempt to document the current state of tribal
knowledge about RSB attacks and what exactly is being mitigated.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:49 +02:00
Josh Poimboeuf
47ae76fb27 KVM: VMX: Fix IBRS handling after vmexit
commit bea7e31a5caccb6fe8ed989c065072354f0ecb52 upstream.

For legacy IBRS to work, the IBRS bit needs to be always re-written
after vmexit, even if it's already on.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:48 +02:00
Josh Poimboeuf
5269be9111 KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS
commit fc02735b14fff8c6678b521d324ade27b1a3d4cf upstream.

On eIBRS systems, the returns in the vmexit return path from
__vmx_vcpu_run() to vmx_vcpu_run() are exposed to RSB poisoning attacks.

Fix that by moving the post-vmexit spec_ctrl handling to immediately
after the vmexit.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:48 +02:00
Josh Poimboeuf
84061fff2a KVM: VMX: Convert launched argument to flags
commit bb06650634d3552c0f8557e9d16aa1a408040e28 upstream.

Convert __vmx_vcpu_run()'s 'launched' argument to 'flags', in
preparation for doing SPEC_CTRL handling immediately after vmexit, which
will need another flag.

This is much easier than adding a fourth argument, because this code
supports both 32-bit and 64-bit, and the fourth argument on 32-bit would
have to be pushed on the stack.

Note that __vmx_vcpu_run_flags() is called outside of the noinstr
critical section because it will soon start calling potentially
traceable functions.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:48 +02:00
Josh Poimboeuf
07401c2311 KVM: VMX: Flatten __vmx_vcpu_run()
commit 8bd200d23ec42d66ccd517a72dd0b9cc6132d2fd upstream.

Move the vmx_vm{enter,exit}() functionality into __vmx_vcpu_run().  This
will make it easier to do the spec_ctrl handling before the first RET.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
[cascardo: remove ENDBR]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:47 +02:00
Josh Poimboeuf
df93717a32 objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}
commit 8faea26e611189e933ea2281975ff4dc7c1106b6 upstream.

Commit

  c536ed2fff ("objtool: Remove SAVE/RESTORE hints")

removed the save/restore unwind hints because they were no longer
needed. Now they're going to be needed again so re-add them.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:47 +02:00
Josh Poimboeuf
1dbefa5772 x86/speculation: Remove x86_spec_ctrl_mask
commit acac5e98ef8d638a411cfa2ee676c87e1973f126 upstream.

This mask has been made redundant by kvm_spec_ctrl_test_value().  And it
doesn't even work when MSR interception is disabled, as the guest can
just write to SPEC_CTRL directly.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:47 +02:00
Josh Poimboeuf
ce11f91b21 x86/speculation: Use cached host SPEC_CTRL value for guest entry/exit
commit bbb69e8bee1bd882784947095ffb2bfe0f7c9470 upstream.

There's no need to recalculate the host value for every entry/exit.
Just use the cached value in spec_ctrl_current().

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:46 +02:00
Josh Poimboeuf
aad83db22e x86/speculation: Fix SPEC_CTRL write on SMT state change
commit 56aa4d221f1ee2c3a49b45b800778ec6e0ab73c5 upstream.

If the SMT state changes, SSBD might get accidentally disabled.  Fix
that.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:46 +02:00
Josh Poimboeuf
d29c07912a x86/speculation: Fix firmware entry SPEC_CTRL handling
commit e6aa13622ea8283cc699cac5d018cc40a2ba2010 upstream.

The firmware entry code may accidentally clear STIBP or SSBD. Fix that.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:46 +02:00
Josh Poimboeuf
f1b01ace81 x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
commit b2620facef4889fefcbf2e87284f34dcd4189bce upstream.

If a kernel is built with CONFIG_RETPOLINE=n, but the user still wants
to mitigate Spectre v2 using IBRS or eIBRS, the RSB filling will be
silently disabled.

There's nothing retpoline-specific about RSB buffer filling.  Remove the
CONFIG_RETPOLINE guards around it.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:46 +02:00
Peter Zijlstra
ea1aa926f4 x86/cpu/amd: Add Spectral Chicken
commit d7caac991feeef1b871ee6988fd2c9725df09039 upstream.

Zen2 uarchs have an undocumented, unnamed, MSR that contains a chicken
bit for some speculation behaviour. It needs setting.

Note: very belatedly AMD released naming; it's now officially called
      MSR_AMD64_DE_CFG2 and MSR_AMD64_DE_CFG2_SUPPRESS_NOBR_PRED_BIT
      but shall remain the SPECTRAL CHICKEN.

Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-25 11:26:45 +02:00