commit 1aa7a5735a upstream
The macro is not type safe and I did look for why that "g" constraint for
the asm doesn't work: it's because the asm is more fundamentally wrong.
It does
movl %[val], %%eax
but "val" isn't a 32-bit value, so then gcc will pass it in a register,
and generate code like
movl %rsi, %eax
and gas will complain about a nonsensical 'mov' instruction (it's moving a
64-bit register to a 32-bit one).
Passing it through memory will just hide the real bug - gcc still thinks
the memory location is 64-bit, but the "movl" will only load the first 32
bits and it all happens to work because x86 is little-endian.
Convert it to a type safe inline function with a little trick which hands
the feature into the ALTERNATIVE macro.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit def9331a12 upstream
When running as Xen pv guest X86_BUG_SYSRET_SS_ATTRS must not be set
on AMD cpus.
This bug/feature bit is kind of special as it will be used very early
when switching threads. Setting the bit and clearing it a little bit
later leaves a critical window where things can go wrong. This time
window has enlarged a little bit by using setup_clear_cpu_cap() instead
of the hypervisor's set_cpu_features callback. It seems this larger
window now makes it rather easy to hit the problem.
The proper solution is to never set the bit in case of Xen.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18bf3c3ea8 upstream.
Flush indirect branches when switching into a process that marked itself
non dumpable. This protects high value processes like gpg better,
without having too high performance overhead.
If done naïvely, we could switch to a kernel idle thread and then back
to the original process, such as:
process A -> idle -> process A
In such scenario, we do not have to do IBPB here even though the process
is non-dumpable, as we are switching back to the same process after a
hiatus.
To avoid the redundant IBPB, which is expensive, we track the last mm
user context ID. The cost is to have an extra u64 mm context id to track
the last mm we were using before switching to the init_mm used by idle.
Avoiding the extra IBPB is probably worth the extra memory for this
common scenario.
For those cases where tlb_defer_switch_to_init_mm() returns true (non
PCID), lazy tlb will defer switch to init_mm, so we will not be changing
the mm for the process A -> idle -> process A switch. So IBPB will be
skipped for this case.
Thanks to the reviewers and Andy Lutomirski for the suggestion of
using ctx_id which got rid of the problem of mm pointer recycling.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: linux@dominikbrodowski.net
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: luto@kernel.org
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/1517263487-3708-1-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 778843f934 upstream
Use of a temporary R8 register here seems to be unnecessary.
"push %r8" is a two-byte insn (it needs REX prefix to specify R8),
"push $0" is two-byte too. It seems just using the latter would be
no worse.
Thus, code had an unnecessary "xorq %r8,%r8" insn.
It probably costs nothing in execution time here since we are probably
limited by store bandwidth at this point, but still.
Run-tested under QEMU: 32-bit calls still work:
/ # ./test_syscall_vdso32
[RUN] Executing 6-argument 32-bit syscall via VDSO
[OK] Arguments are preserved across syscall
[NOTE] R11 has changed:0000000000200ed7 - assuming clobbered by SYSRET insn
[OK] R8..R15 did not leak kernel data
[RUN] Executing 6-argument 32-bit syscall via INT 80
[OK] Arguments are preserved across syscall
[OK] R8..R15 did not leak kernel data
[RUN] Running tests under ptrace
[RUN] Executing 6-argument 32-bit syscall via VDSO
[OK] Arguments are preserved across syscall
[NOTE] R11 has changed:0000000000200ed7 - assuming clobbered by SYSRET insn
[OK] R8..R15 did not leak kernel data
[RUN] Executing 6-argument 32-bit syscall via INT 80
[OK] Arguments are preserved across syscall
[OK] R8..R15 did not leak kernel data
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1462201010-16846-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 7fcae1118f)
Despite the fact that all the other code there seems to be doing it, just
using set_cpu_cap() in early_intel_init() doesn't actually work.
For CPUs with PKU support, setup_pku() calls get_cpu_cap() after
c->c_init() has set those feature bits. That resets those bits back to what
was queried from the hardware.
Turning the bits off for bad microcode is easy to fix. That can just use
setup_clear_cpu_cap() to force them off for all CPUs.
I was less keen on forcing the feature bits *on* that way, just in case
of inconsistencies. I appreciate that the kernel is going to get this
utterly wrong if CPU features are not consistent, because it has already
applied alternatives by the time secondary CPUs are brought up.
But at least if setup_force_cpu_cap() isn't being used, we might have a
chance of *detecting* the lack of the corresponding bit and either
panicking or refusing to bring the offending CPU online.
So ensure that the appropriate feature bits are set within get_cpu_cap()
regardless of how many extra times it's called.
Fixes: 2961298e ("x86/cpufeatures: Clean up Spectre v2 related CPUID flags")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: karahmed@amazon.de
Cc: peterz@infradead.org
Cc: bp@alien8.de
Link: https://lkml.kernel.org/r/1517322623-15261-1-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 229bc19fd7 upstream.
Don't rely on event interrupt (EINT) bit alone to detect pending port
change in resume. If no change event is detected the host may be suspended
again, oterwise roothubs are resumed.
There is a lag in xHC setting EINT. If we don't notice the pending change
in resume, and the controller is runtime suspeded again, it causes the
event handler to assume host is dead as it will fail to read xHC registers
once PCI puts the controller to D3 state.
[ 268.520969] xhci_hcd: xhci_resume: starting port polling.
[ 268.520985] xhci_hcd: xhci_hub_status_data: stopping port polling.
[ 268.521030] xhci_hcd: xhci_suspend: stopping port polling.
[ 268.521040] xhci_hcd: // Setting command ring address to 0x349bd001
[ 268.521139] xhci_hcd: Port Status Change Event for port 3
[ 268.521149] xhci_hcd: resume root hub
[ 268.521163] xhci_hcd: port resume event for port 3
[ 268.521168] xhci_hcd: xHC is not running.
[ 268.521174] xhci_hcd: handle_port_status: starting port polling.
[ 268.596322] xhci_hcd: xhci_hc_died: xHCI host controller not responding, assume dead
The EINT lag is described in a additional note in xhci specs 4.19.2:
"Due to internal xHC scheduling and system delays, there will be a lag
between a change bit being set and the Port Status Change Event that it
generated being written to the Event Ring. If SW reads the PORTSC and
sees a change bit set, there is no guarantee that the corresponding Port
Status Change Event has already been written into the Event Ring."
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e78bfb0751 ]
Commit 8b7008620b ("net: Don't copy pfmemalloc flag in
__copy_skb_header()") introduced a different handling for the
pfmemalloc flag in copy and clone paths.
In __skb_clone(), now, the flag is set only if it was set in the
original skb, but not cleared if it wasn't. This is wrong and
might lead to socket buffers being flagged with pfmemalloc even
if the skb data wasn't allocated from pfmemalloc reserves. Copy
the flag instead of ORing it.
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: 8b7008620b ("net: Don't copy pfmemalloc flag in __copy_skb_header()")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8b7008620b ]
The pfmemalloc flag indicates that the skb was allocated from
the PFMEMALLOC reserves, and the flag is currently copied on skb
copy and clone.
However, an skb copied from an skb flagged with pfmemalloc
wasn't necessarily allocated from PFMEMALLOC reserves, and on
the other hand an skb allocated that way might be copied from an
skb that wasn't.
So we should not copy the flag on skb copy, and rather decide
whether to allow an skb to be associated with sockets unrelated
to page reclaim depending only on how it was allocated.
Move the pfmemalloc flag before headers_start[0] using an
existing 1-bit hole, so that __copy_skb_header() doesn't copy
it.
When cloning, we'll now take care of this flag explicitly,
contravening to the warning comment of __skb_clone().
While at it, restore the newline usage introduced by commit
b193722731 ("net: reorganize sk_buff for faster
__copy_skb_header()") to visually separate bytes used in
bitfields after headers_start[0], that was gone after commit
a9e419dc7b ("netfilter: merge ctinfo into nfct pointer storage
area"), and describe the pfmemalloc flag in the kernel-doc
structure comment.
This doesn't change the size of sk_buff or cacheline boundaries,
but consolidates the 15 bits hole before tc_index into a 2 bytes
hole before csum, that could now be filled more easily.
Reported-by: Patrick Talbert <ptalbert@redhat.com>
Fixes: c93bdd0e03 ("netvm: allow skb allocation to use PFMEMALLOC reserves")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9ba8376ce1 ]
It seems that a *break* is missing in order to avoid falling through
to the default case. Otherwise, checking *chan* makes no sense.
Fixes: 72df7a7244 ("ptp: Allow reassigning calibration pin function")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit df8ed346d4 ]
Currently also the pause flags are removed from phydev->supported because
they're not included in PHY_DEFAULT_FEATURES. I don't think this is
intended, especially when considering that this function can be called
via phy_set_max_speed() anywhere in a driver. Change the masking to mask
out only the values we're going to change. In addition remove the
misleading comment, job of this small function is just to adjust the
supported and advertised speeds.
Fixes: f3a6bd393c ("phylib: Add phy_set_max_speed helper")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e7372197e1 ]
Xin reported that icmp replies may not use the address on the device the
echo request is received if the destination address is broadcast. Instead
a route lookup is done without considering VRF context. Fix by setting
oif in flow struct to the master device if it is enslaved. That directs
the lookup to the VRF table. If the device is not enslaved, oif is still
0 so no affect.
Fixes: cd2fbe1b6b ("net: Use VRF device index for lookups on RX")
Reported-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 107d01f5ba ]
rhashtable_init() currently does not take into account the user-passed
min_size parameter unless param->nelem_hint is set as well. As such,
the default size (number of buckets) will always be HASH_DEFAULT_SIZE
even if the smallest allowed size is larger than that. Remediate this
by unconditionally calling into rounded_hashtable_size() and handling
things accordingly.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 169dc027fb ]
The rol32 call is currently rotating hash but the rol'd value is
being discarded. I believe the current code is incorrect and hash
should be assigned the rotated value returned from rol32.
Thanks to David Lebrun for spotting this.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 70ba5b6db9 ]
The low and high values of the net.ipv4.ping_group_range sysctl were
being silently forced to the default disabled state when a write to the
sysctl contained GIDs that didn't map to the associated user namespace.
Confusingly, the sysctl's write operation would return success and then
a subsequent read of the sysctl would indicate that the low and high
values are the overflowgid.
This patch changes the behavior by clearly returning an error when the
sysctl write operation receives a GID range that doesn't map to the
associated user namespace. In such a situation, the previous value of
the sysctl is preserved and that range will be returned in a subsequent
read of the sysctl.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9f15bde671 upstream.
It was reported that a kernel crash happened in mem_cgroup_iter(), which
can be triggered if the legacy cgroup-v1 non-hierarchical mode is used.
Unable to handle kernel paging request at virtual address 6b6b6b6b6b6b8f
......
Call trace:
mem_cgroup_iter+0x2e0/0x6d4
shrink_zone+0x8c/0x324
balance_pgdat+0x450/0x640
kswapd+0x130/0x4b8
kthread+0xe8/0xfc
ret_from_fork+0x10/0x20
mem_cgroup_iter():
......
if (css_tryget(css)) <-- crash here
break;
......
The crashing reason is that mem_cgroup_iter() uses the memcg object whose
pointer is stored in iter->position, which has been freed before and
filled with POISON_FREE(0x6b).
And the root cause of the use-after-free issue is that
invalidate_reclaim_iterators() fails to reset the value of iter->position
to NULL when the css of the memcg is released in non- hierarchical mode.
Link: http://lkml.kernel.org/r/1531994807-25639-1-git-send-email-jing.xia@unisoc.com
Fixes: 6df38689e0 ("mm: memcontrol: fix possible memcg leak due to interrupted reclaim")
Signed-off-by: Jing Xia <jing.xia.mail@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <chunyan.zhang@unisoc.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 93312b6da4 upstream.
mprotect(EXEC) was failing for stack mappings as default vm flags was
missing MAYEXEC.
This was triggered by glibc test suite nptl/tst-execstack testcase
What is surprising is that despite running LTP for years on, we didn't
catch this issue as it lacks a directed test case.
gcc dejagnu tests with nested functions also requiring exec stack work
fine though because they rely on the GNU_STACK segment spit out by
compiler and handled in kernel elf loader.
This glibc case is different as the stack is non exec to begin with and
a dlopen of shared lib with GNU_STACK segment triggers the exec stack
proceedings using a mprotect(PROT_EXEC) which was broken.
CC: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e3761145a upstream.
swap was broken on ARC due to silly copy-paste issue.
We encode offset from swapcache page in __swp_entry() as (off << 13) but
were not decoding back in __swp_offset() as (off >> 13) - it was still
(off << 13).
This finally fixes swap usage on ARC.
| # mkswap /dev/sda2
|
| # swapon -a -e /dev/sda2
| Adding 500728k swap on /dev/sda2. Priority:-2 extents:1 across:500728k
|
| # free
| total used free shared buffers cached
| Mem: 765104 13456 751648 4736 8 4736
| -/+ buffers/cache: 8712 756392
| Swap: 500728 0 500728
Cc: stable@vger.kernel.org
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b5020a8e6b upstream.
Syzbot reports crashes in kvm_irqfd_assign(), caused by use-after-free
when kvm_irqfd_assign() and kvm_irqfd_deassign() run in parallel
for one specific eventfd. When the assign path hasn't finished but irqfd
has been added to kvm->irqfds.items list, another thead may deassign the
eventfd and free struct kvm_kernel_irqfd(). The assign path then uses
the struct kvm_kernel_irqfd that has been freed by deassign path. To avoid
such issue, keep irqfd under kvm->irq_srcu protection after the irqfd
has been added to kvm->irqfds.items list, and call synchronize_srcu()
in irq_shutdown() to make sure that irqfd has been fully initialized in
the assign path.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Tianyu Lan <tianyu.lan@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
