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commit 16d51a590a8ce3befb1308e0e7ab77f3b661af33 upstream.
When going through execve(), zero out the NUMA fault statistics instead of
freeing them.
During execve, the task is reachable through procfs and the scheduler. A
concurrent /proc/*/sched reader can read data from a freed ->numa_faults
allocation (confirmed by KASAN) and write it back to userspace.
I believe that it would also be possible for a use-after-free read to occur
through a race between a NUMA fault and execve(): task_numa_fault() can
lead to task_numa_compare(), which invokes task_weight() on the currently
running task of a different CPU.
Another way to fix this would be to make ->numa_faults RCU-managed or add
extra locking, but it seems easier to wipe the NUMA fault statistics on
execve.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Fixes: 82727018b0d3 ("sched/numa: Call task_numa_free() from do_execve()")
Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 201c1db90cd643282185a00770f12f95da330eca upstream.
The stub function for !CONFIG_IOMMU_IOVA needs to be
'static inline'.
Fixes: effa467870c76 ('iommu/vt-d: Don't queue_iova() if there is no flush queue')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit effa467870c7612012885df4e246bdb8ffd8e44c upstream.
Intel VT-d driver was reworked to use common deferred flushing
implementation. Previously there was one global per-cpu flush queue,
afterwards - one per domain.
Before deferring a flush, the queue should be allocated and initialized.
Currently only domains with IOMMU_DOMAIN_DMA type initialize their flush
queue. It's probably worth to init it for static or unmanaged domains
too, but it may be arguable - I'm leaving it to iommu folks.
Prevent queuing an iova flush if the domain doesn't have a queue.
The defensive check seems to be worth to keep even if queue would be
initialized for all kinds of domains. And is easy backportable.
On 4.19.43 stable kernel it has a user-visible effect: previously for
devices in si domain there were crashes, on sata devices:
BUG: spinlock bad magic on CPU#6, swapper/0/1
lock: 0xffff88844f582008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #1
Call Trace:
<IRQ>
dump_stack+0x61/0x7e
spin_bug+0x9d/0xa3
do_raw_spin_lock+0x22/0x8e
_raw_spin_lock_irqsave+0x32/0x3a
queue_iova+0x45/0x115
intel_unmap+0x107/0x113
intel_unmap_sg+0x6b/0x76
__ata_qc_complete+0x7f/0x103
ata_qc_complete+0x9b/0x26a
ata_qc_complete_multiple+0xd0/0xe3
ahci_handle_port_interrupt+0x3ee/0x48a
ahci_handle_port_intr+0x73/0xa9
ahci_single_level_irq_intr+0x40/0x60
__handle_irq_event_percpu+0x7f/0x19a
handle_irq_event_percpu+0x32/0x72
handle_irq_event+0x38/0x56
handle_edge_irq+0x102/0x121
handle_irq+0x147/0x15c
do_IRQ+0x66/0xf2
common_interrupt+0xf/0xf
RIP: 0010:__do_softirq+0x8c/0x2df
The same for usb devices that use ehci-pci:
BUG: spinlock bad magic on CPU#0, swapper/0/1
lock: 0xffff88844f402008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #4
Call Trace:
<IRQ>
dump_stack+0x61/0x7e
spin_bug+0x9d/0xa3
do_raw_spin_lock+0x22/0x8e
_raw_spin_lock_irqsave+0x32/0x3a
queue_iova+0x77/0x145
intel_unmap+0x107/0x113
intel_unmap_page+0xe/0x10
usb_hcd_unmap_urb_setup_for_dma+0x53/0x9d
usb_hcd_unmap_urb_for_dma+0x17/0x100
unmap_urb_for_dma+0x22/0x24
__usb_hcd_giveback_urb+0x51/0xc3
usb_giveback_urb_bh+0x97/0xde
tasklet_action_common.isra.4+0x5f/0xa1
tasklet_action+0x2d/0x30
__do_softirq+0x138/0x2df
irq_exit+0x7d/0x8b
smp_apic_timer_interrupt+0x10f/0x151
apic_timer_interrupt+0xf/0x20
</IRQ>
RIP: 0010:_raw_spin_unlock_irqrestore+0x17/0x39
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: <stable@vger.kernel.org> # 4.14+
Fixes: 13cf01744608 ("iommu/vt-d: Make use of iova deferred flushing")
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
[v4.14-port notes:
o minor conflict with untrusted IOMMU devices check under if-condition
o setup_timer() near one chunk is timer_setup() in v5.3]
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 3b4477d2dcf2709d0be89e2a8dced3d0f4a017f2 upstream.
There are two state fields: socket->state and sock->sk_state. The
socket->state field uses SS_UNCONNECTED, SS_CONNECTED, etc while the
sock->sk_state typically uses values that match TCP state constants
(TCP_CLOSE, TCP_ESTABLISHED). AF_VSOCK does not follow this convention
and instead uses SS_* constants for both fields.
The sk_state field will be exposed to userspace through the vsock_diag
interface for ss(8), netstat(8), and other programs.
This patch switches sk_state to TCP state constants so that the meaning
of this field is consistent with other address families. Not just
AF_INET and AF_INET6 use the TCP constants, AF_UNIX and others do too.
The following mapping was used to convert the code:
SS_FREE -> TCP_CLOSE
SS_UNCONNECTED -> TCP_CLOSE
SS_CONNECTING -> TCP_SYN_SENT
SS_CONNECTED -> TCP_ESTABLISHED
SS_DISCONNECTING -> TCP_CLOSING
VSOCK_SS_LISTEN -> TCP_LISTEN
In __vsock_create() the sk_state initialization was dropped because
sock_init_data() already initializes sk_state to TCP_CLOSE.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[Adjusted net/vmw_vsock/hyperv_transport.c since the commit
b4562ca7925a ("hv_sock: add locking in the open/close/release code paths")
and the commit
c9d3fe9da094 ("VSOCK: fix outdated sk_state value in hvs_release()")
were backported before 3b4477d2dcf2.]
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit d7852fbd0f0423937fa287a598bfde188bb68c22 upstream.
It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU
work because it installs a temporary credential that gets allocated and
freed for each system call.
The allocation and freeing overhead is mostly benign, but because
credentials can be accessed under the RCU read lock, the freeing
involves a RCU grace period.
Which is not a huge deal normally, but if you have a lot of access()
calls, this causes a fair amount of seconday damage: instead of having a
nice alloc/free patterns that hits in hot per-CPU slab caches, you have
all those delayed free's, and on big machines with hundreds of cores,
the RCU overhead can end up being enormous.
But it turns out that all of this is entirely unnecessary. Exactly
because access() only installs the credential as the thread-local
subjective credential, the temporary cred pointer doesn't actually need
to be RCU free'd at all. Once we're done using it, we can just free it
synchronously and avoid all the RCU overhead.
So add a 'non_rcu' flag to 'struct cred', which can be set by users that
know they only use it in non-RCU context (there are other potential
users for this). We can make it a union with the rcu freeing list head
that we need for the RCU case, so this doesn't need any extra storage.
Note that this also makes 'get_current_cred()' clear the new non_rcu
flag, in case we have filesystems that take a long-term reference to the
cred and then expect the RCU delayed freeing afterwards. It's not
entirely clear that this is required, but it makes for clear semantics:
the subjective cred remains non-RCU as long as you only access it
synchronously using the thread-local accessors, but you _can_ use it as
a generic cred if you want to.
It is possible that we should just remove the whole RCU markings for
->cred entirely. Only ->real_cred is really supposed to be accessed
through RCU, and the long-term cred copies that nfs uses might want to
explicitly re-enable RCU freeing if required, rather than have
get_current_cred() do it implicitly.
But this is a "minimal semantic changes" change for the immediate
problem.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Glauber <jglauber@marvell.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jayachandran Chandrasekharan Nair <jnair@marvell.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit a012024571d98e2e4bf29a9168fb7ddc44b7ab86 ]
This reduces the amount of spam when you debug a CRC reading
program.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[mlankhorst: Change bool overflow to was_overflow (Ville)]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180418125121.72081-1-maarten.lankhorst@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 6ba0e7dc64a5adcda2fbe65adc466891795d639e upstream.
Currently both journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() operate on the entire address space
of each of the inodes associated with a given journal entry. The
consequence of this is that if we have an inode where we are constantly
appending dirty pages we can end up waiting for an indefinite amount of
time in journal_finish_inode_data_buffers() while we wait for all the
pages under writeback to be written out.
The easiest way to cause this type of workload is do just dd from
/dev/zero to a file until it fills the entire filesystem. This can
cause journal_finish_inode_data_buffers() to wait for the duration of
the entire dd operation.
We can improve this situation by scoping each of the inode dirty ranges
associated with a given transaction. We do this via the jbd2_inode
structure so that the scoping is contained within jbd2 and so that it
follows the lifetime and locking rules for that structure.
This allows us to limit the writeback & wait in
journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() respectively to the dirty range for
a given struct jdb2_inode, keeping us from waiting forever if the inode
in question is still being appended to.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit aa0bfcd939c30617385ffa28682c062d78050eba upstream.
In the spirit of filemap_fdatawait_range() and
filemap_fdatawait_keep_errors(), introduce
filemap_fdatawait_range_keep_errors() which both takes a range upon
which to wait and does not clear errors from the address space.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 8d650cdedaabb33e85e9b7c517c0c71fcecc1de9 ]
Neal reported incorrect use of ns_capable() from bpf hook.
bpf_setsockopt(...TCP_CONGESTION...)
-> tcp_set_congestion_control()
-> ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)
-> ns_capable_common()
-> current_cred()
-> rcu_dereference_protected(current->cred, 1)
Accessing 'current' in bpf context makes no sense, since packets
are processed from softirq context.
As Neal stated : The capability check in tcp_set_congestion_control()
was written assuming a system call context, and then was reused from
a BPF call site.
The fix is to add a new parameter to tcp_set_congestion_control(),
so that the ns_capable() call is only performed under the right
context.
Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Lawrence Brakmo <brakmo@fb.com>
Reported-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit b60a77386b1d4868f72f6353d35dabe5fbe981f2 ]
netfilter did not expect that skb_dst_force() can cause skb to lose its
dst entry.
I got a bug report with a skb->dst NULL dereference in netfilter
output path. The backtrace contains nf_reinject(), so the dst might have
been cleared when skb got queued to userspace.
Other users were fixed via
if (skb_dst(skb)) {
skb_dst_force(skb);
if (!skb_dst(skb))
goto handle_err;
}
But I think its preferable to make the 'dst might be cleared' part
of the function explicit.
In netfilter case, skb with a null dst is expected when queueing in
prerouting hook, so drop skb for the other hooks.
v2:
v1 of this patch returned true in case skb had no dst entry.
Eric said:
Say if we have two skb_dst_force() calls for some reason
on the same skb, only the first one will return false.
This now returns false even when skb had no dst, as per Erics
suggestion, so callers might need to check skb_dst() first before
skb_dst_force().
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 7f1e541fc8d57a143dd5df1d0a1276046e08c083 ]
Sometimes we know that it's safe to do potentially out-of-bounds access
because we know it won't cross a page boundary. Still, KASAN will
report this as a bug.
Add read_word_at_a_time() function which is supposed to be used in such
cases. In read_word_at_a_time() KASAN performs relaxed check - only the
first byte of access is validated.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit bdb5ac801af3d81d36732c2f640d6a1d3df83826 ]
Instead of having two identical __read_once_size_nocheck() functions
with different attributes, consolidate all the difference in new macro
__no_kasan_or_inline and use it. No functional changes.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit bce5963bcb4f9934faa52be323994511d59fd13c upstream.
When binding an interdomain event channel to a vcpu via
IOCTL_EVTCHN_BIND_INTERDOMAIN not only the event channel needs to be
bound, but the affinity of the associated IRQi must be changed, too.
Otherwise the IRQ and the event channel won't be moved to another vcpu
in case the original vcpu they were bound to is going offline.
Cc: <stable@vger.kernel.org> # 4.13
Fixes: c48f64ab472389df ("xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 6282edb72bed5324352522d732080d4c1b9dfed6 ]
Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT
(Multi Core Timer) and standard ARM Architected Timers.
There are use cases, where both timer interfaces are used simultanously.
One of such examples is using Exynos MCT for the main system timer and
ARM Architected Timers for the KVM and virtualized guests (KVM requires
arch timers).
Exynos Multi-Core Timer driver (exynos_mct) must be however started
before ARM Architected Timers (arch_timer), because they both share some
common hardware blocks (global system counter) and turning on MCT is
needed to get ARM Architected Timer working properly.
To ensure selecting Exynos MCT as the main system timer, increase MCT
timer rating. To ensure proper starting order of both timers during
suspend/resume cycle, increase MCT hotplug priority over ARM Archictected
Timers.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 5db7c8b9f9fc2aeec671ae3ca6375752c162e0e7 ]
syzkaller reports for memory leak in start_sync_thread [1]
As Eric points out, kthread may start and stop before the
threadfn function is called, so there is no chance the
data (tinfo in our case) to be released in thread.
Fix this by releasing tinfo in the controlling code instead.
[1]
BUG: memory leak
unreferenced object 0xffff8881206bf700 (size 32):
comm "syz-executor761", pid 7268, jiffies 4294943441 (age 20.470s)
hex dump (first 32 bytes):
00 40 7c 09 81 88 ff ff 80 45 b8 21 81 88 ff ff .@|......E.!....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<0000000057619e23>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline]
[<0000000057619e23>] slab_post_alloc_hook mm/slab.h:439 [inline]
[<0000000057619e23>] slab_alloc mm/slab.c:3326 [inline]
[<0000000057619e23>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
[<0000000086ce5479>] kmalloc include/linux/slab.h:547 [inline]
[<0000000086ce5479>] start_sync_thread+0x5d2/0xe10 net/netfilter/ipvs/ip_vs_sync.c:1862
[<000000001a9229cc>] do_ip_vs_set_ctl+0x4c5/0x780 net/netfilter/ipvs/ip_vs_ctl.c:2402
[<00000000ece457c8>] nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
[<00000000ece457c8>] nf_setsockopt+0x4c/0x80 net/netfilter/nf_sockopt.c:115
[<00000000942f62d4>] ip_setsockopt net/ipv4/ip_sockglue.c:1258 [inline]
[<00000000942f62d4>] ip_setsockopt+0x9b/0xb0 net/ipv4/ip_sockglue.c:1238
[<00000000a56a8ffd>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616
[<00000000fa895401>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130
[<0000000095eef4cf>] __sys_setsockopt+0x98/0x120 net/socket.c:2078
[<000000009747cf88>] __do_sys_setsockopt net/socket.c:2089 [inline]
[<000000009747cf88>] __se_sys_setsockopt net/socket.c:2086 [inline]
[<000000009747cf88>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086
[<00000000ded8ba80>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301
[<00000000893b4ac8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported-by: syzbot+7e2e50c8adfccd2e5041@syzkaller.appspotmail.com
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 998e7a76804b ("ipvs: Use kthread_run() instead of doing a double-fork via kernel_thread()")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6da9f775175e516fc7229ceaa9b54f8f56aa7924 ]
When debugging options are turned on, the rcu_read_lock() function
might not be inlined. This results in lockdep's print_lock() function
printing "rcu_read_lock+0x0/0x70" instead of rcu_read_lock()'s caller.
For example:
[ 10.579995] =============================
[ 10.584033] WARNING: suspicious RCU usage
[ 10.588074] 4.18.0.memcg_v2+ #1 Not tainted
[ 10.593162] -----------------------------
[ 10.597203] include/linux/rcupdate.h:281 Illegal context switch in
RCU read-side critical section!
[ 10.606220]
[ 10.606220] other info that might help us debug this:
[ 10.606220]
[ 10.614280]
[ 10.614280] rcu_scheduler_active = 2, debug_locks = 1
[ 10.620853] 3 locks held by systemd/1:
[ 10.624632] #0: (____ptrval____) (&type->i_mutex_dir_key#5){.+.+}, at: lookup_slow+0x42/0x70
[ 10.633232] #1: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70
[ 10.640954] #2: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70
These "rcu_read_lock+0x0/0x70" strings are not providing any useful
information. This commit therefore forces inlining of the rcu_read_lock()
function so that rcu_read_lock()'s caller is instead shown.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 8f9fab480c7a87b10bb5440b5555f370272a5d59 ]
DIV_ROUND_UP_ULL adds the two arguments and then invokes
DIV_ROUND_DOWN_ULL. But on a 32bit system the addition of two 32 bit
values can overflow. DIV_ROUND_DOWN_ULL does it correctly and stashes
the addition into a unsigned long long so cast the result to unsigned
long long here to avoid the overflow condition.
[akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval]
Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 1c2eb5b2853c9f513690ba6b71072d8eb65da16a upstream.
The VMCI handle array has an integer overflow in
vmci_handle_arr_append_entry when it tries to expand the array. This can be
triggered from a guest, since the doorbell link hypercall doesn't impose a
limit on the number of doorbell handles that a VM can create in the
hypervisor, and these handles are stored in a handle array.
In this change, we introduce a mandatory max capacity for handle
arrays/lists to avoid excessive memory usage.
Signed-off-by: Vishnu Dasa <vdasa@vmware.com>
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 6f6a8622057c92408930c31698394fae1557b188 ]
A similar fix to Patch "ip_tunnel: allow not to count pkts on tstats by
setting skb's dev to NULL" is also needed by ip6_tunnel.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream.
The cacheinfo structures are alloced/freed by cpu online/offline
callbacks. Originally these were only used by sysfs to expose the
cache topology to user space. Without any in-kernel dependencies
CPUHP_AP_ONLINE_DYN was an appropriate choice.
resctrl has started using these structures to identify CPUs that
share a cache. It updates its 'domain' structures from cpu
online/offline callbacks. These depend on the cacheinfo structures
(resctrl_online_cpu()->domain_add_cpu()->get_cache_id()->
get_cpu_cacheinfo()).
These also run as CPUHP_AP_ONLINE_DYN.
Now that there is an in-kernel dependency, move the cacheinfo
work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN
work runs.
Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology")
Cc: <stable@vger.kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit c32cc30c0544f13982ee0185d55f4910319b1a79 upstream.
cpu_to_le32/le32_to_cpu is defined in include/linux/byteorder/generic.h,
which is not exported to user-space.
UAPI headers must use the ones prefixed with double-underscore.
Detected by compile-testing exported headers:
include/linux/nilfs2_ondisk.h: In function `nilfs_checkpoint_set_snapshot':
include/linux/nilfs2_ondisk.h:536:17: error: implicit declaration of function `cpu_to_le32' [-Werror=implicit-function-declaration]
cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) | \
^
include/linux/nilfs2_ondisk.h:552:1: note: in expansion of macro `NILFS_CHECKPOINT_FNS'
NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot)
^~~~~~~~~~~~~~~~~~~~
include/linux/nilfs2_ondisk.h:536:29: error: implicit declaration of function `le32_to_cpu' [-Werror=implicit-function-declaration]
cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) | \
^
include/linux/nilfs2_ondisk.h:552:1: note: in expansion of macro `NILFS_CHECKPOINT_FNS'
NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot)
^~~~~~~~~~~~~~~~~~~~
include/linux/nilfs2_ondisk.h: In function `nilfs_segment_usage_set_clean':
include/linux/nilfs2_ondisk.h:622:19: error: implicit declaration of function `cpu_to_le64' [-Werror=implicit-function-declaration]
su->su_lastmod = cpu_to_le64(0);
^~~~~~~~~~~
Link: http://lkml.kernel.org/r/20190605053006.14332-1-yamada.masahiro@socionext.com
Fixes: e63e88bc53ba ("nilfs2: move ioctl interface and disk layout to uapi separately")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: <stable@vger.kernel.org> [4.9+]
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>
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commit 427503519739e779c0db8afe876c1b33f3ac60ae upstream.
The architecture implementations of 'arch_futex_atomic_op_inuser()' and
'futex_atomic_cmpxchg_inatomic()' are permitted to return only -EFAULT,
-EAGAIN or -ENOSYS in the case of failure.
Update the comments in the asm-generic/ implementation and also a stray
reference in the robust futex documentation.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This reverts commit 82017e26e51596ee577171a33f357377ec6513b5, which is
upstream commit fe0640eb30b7da261ae84d252ed9ed3c7e68dfd8.
On Fri, Jun 28, 2019 at 8:53 AM Tony Battersby <tonyb@cybernetics.com> wrote:
>
> Old versions of gcc cannot compile 4.14 since 4.14.113:
>
> ./include/asm-generic/fixmap.h:37: error: implicit declaration of function ‘__builtin_unreachable’
>
> The stable commit that caused the problem is 82017e26e515 ("compiler.h:
> update definition of unreachable()") (upstream commit fe0640eb30b7).
> Reverting the commit fixes the problem.
>
> Kernel 4.17 dropped support for older versions of gcc in upstream commit
> cafa0010cd51 ("Raise the minimum required gcc version to 4.6"). This
> was not backported to 4.14 since that would go against the stable kernel
> rules.
>
> Upstream commit 815f0ddb346c ("include/linux/compiler*.h: make
> compiler-*.h mutually exclusive") was a fix for cafa0010cd51. This was
> not backported to 4.14.
>
> Upstream commit fe0640eb30b7 ("compiler.h: update definition of
> unreachable()") was a fix for 815f0ddb346c. This is the commit that was
> backported to 4.14. But it only fixed a problem introduced in the other
> commits, and without those commits, it ends up introducing a problem
> instead of fixing one. So I recommend reverting that patch in 4.14,
> which will enable old gcc to compile 4.14 again. If I understand
> correctly, I believe that clang will still be able to compile 4.14 with
> the patch reverted, although I haven't tried to compile with clang.
>
> The problematic commit is not present in 4.9.x, 4.4.x, 3.18.x, or 3.16.x.
CC: Nick Desaulniers <ndesaulniers@google.com>
CC: Tony Battersby <tonyb@cybernetics.com>,
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 0aa69fd32a5f766e997ca8ab4723c5a1146efa8b ]
For the upcoming removal of buffer heads in XFS we need to keep track of
the number of outstanding writeback requests per page. For this we need
to know if bio_add_page merged a region with the previous bvec or not.
Instead of adding additional arguments this refactors bio_add_page to
be implemented using three lower level helpers which users like XFS can
use directly if they care about the merge decisions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.
The minimum encryption key size for LE connections is 56 bits and to
align LE with BR/EDR, enforce 56 bits of minimum encryption key size for
BR/EDR connections as well.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 59ea6d06cfa9247b586a695c21f94afa7183af74 upstream.
When fixing the race conditions between the coredump and the mmap_sem
holders outside the context of the process, we focused on
mmget_not_zero()/get_task_mm() callers in 04f5866e41fb70 ("coredump: fix
race condition between mmget_not_zero()/get_task_mm() and core
dumping"), but those aren't the only cases where the mmap_sem can be
taken outside of the context of the process as Michal Hocko noticed
while backporting that commit to older -stable kernels.
If mmgrab() is called in the context of the process, but then the
mm_count reference is transferred outside the context of the process,
that can also be a problem if the mmap_sem has to be taken for writing
through that mm_count reference.
khugepaged registration calls mmgrab() in the context of the process,
but the mmap_sem for writing is taken later in the context of the
khugepaged kernel thread.
collapse_huge_page() after taking the mmap_sem for writing doesn't
modify any vma, so it's not obvious that it could cause a problem to the
coredump, but it happens to modify the pmd in a way that breaks an
invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page()
needs the mmap_sem for writing just to block concurrent page faults that
call pmd_trans_huge_lock().
Specifically the invariant that "!pmd_trans_huge()" cannot become a
"pmd_trans_huge()" doesn't hold while collapse_huge_page() runs.
The coredump will call __get_user_pages() without mmap_sem for reading,
which eventually can invoke a lockless page fault which will need a
functional pmd_trans_huge_lock().
So collapse_huge_page() needs to use mmget_still_valid() to check it's
not running concurrently with the coredump... as long as the coredump
can invoke page faults without holding the mmap_sem for reading.
This has "Fixes: khugepaged" to facilitate backporting, but in my view
it's more a bug in the coredump code that will eventually have to be
rewritten to stop invoking page faults without the mmap_sem for reading.
So the long term plan is still to drop all mmget_still_valid().
Link: http://lkml.kernel.org/r/20190607161558.32104-1-aarcange@redhat.com
Fixes: ba76149f47d8 ("thp: khugepaged")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.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>
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commit 78f4e932f7760d965fb1569025d1576ab77557c5 upstream.
Adric Blake reported the following warning during suspend-resume:
Enabling non-boot CPUs ...
x86: Booting SMP configuration:
smpboot: Booting Node 0 Processor 1 APIC 0x2
unchecked MSR access error: WRMSR to 0x10f (tried to write 0x0000000000000000) \
at rIP: 0xffffffff8d267924 (native_write_msr+0x4/0x20)
Call Trace:
intel_set_tfa
intel_pmu_cpu_starting
? x86_pmu_dead_cpu
x86_pmu_starting_cpu
cpuhp_invoke_callback
? _raw_spin_lock_irqsave
notify_cpu_starting
start_secondary
secondary_startup_64
microcode: sig=0x806ea, pf=0x80, revision=0x96
microcode: updated to revision 0xb4, date = 2019-04-01
CPU1 is up
The MSR in question is MSR_TFA_RTM_FORCE_ABORT and that MSR is emulated
by microcode. The log above shows that the microcode loader callback
happens after the PMU restoration, leading to the conjecture that
because the microcode hasn't been updated yet, that MSR is not present
yet, leading to the #GP.
Add a microcode loader-specific hotplug vector which comes before
the PERF vectors and thus executes earlier and makes sure the MSR is
present.
Fixes: 400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort")
Reported-by: Adric Blake <promarbler14@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: x86@kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=203637
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 18fa84a2db0e15b02baa5d94bdb5bd509175d2f6 upstream.
A PF_EXITING task can stay associated with an offline css. If such
task calls task_get_css(), it can get stuck indefinitely. This can be
triggered by BSD process accounting which writes to a file with
PF_EXITING set when racing against memcg disable as in the backtrace
at the end.
After this change, task_get_css() may return a css which was already
offline when the function was called. None of the existing users are
affected by this change.
INFO: rcu_sched self-detected stall on CPU
INFO: rcu_sched detected stalls on CPUs/tasks:
...
NMI backtrace for cpu 0
...
Call Trace:
<IRQ>
dump_stack+0x46/0x68
nmi_cpu_backtrace.cold.2+0x13/0x57
nmi_trigger_cpumask_backtrace+0xba/0xca
rcu_dump_cpu_stacks+0x9e/0xce
rcu_check_callbacks.cold.74+0x2af/0x433
update_process_times+0x28/0x60
tick_sched_timer+0x34/0x70
__hrtimer_run_queues+0xee/0x250
hrtimer_interrupt+0xf4/0x210
smp_apic_timer_interrupt+0x56/0x110
apic_timer_interrupt+0xf/0x20
</IRQ>
RIP: 0010:balance_dirty_pages_ratelimited+0x28f/0x3d0
...
btrfs_file_write_iter+0x31b/0x563
__vfs_write+0xfa/0x140
__kernel_write+0x4f/0x100
do_acct_process+0x495/0x580
acct_process+0xb9/0xdb
do_exit+0x748/0xa00
do_group_exit+0x3a/0xa0
get_signal+0x254/0x560
do_signal+0x23/0x5c0
exit_to_usermode_loop+0x5d/0xa0
prepare_exit_to_usermode+0x53/0x80
retint_user+0x8/0x8
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v4.2+
Fixes: ec438699a9ae ("cgroup, block: implement task_get_css() and use it in bio_associate_current()")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream.
Some TCP peers announce a very small MSS option in their SYN and/or
SYN/ACK messages.
This forces the stack to send packets with a very high network/cpu
overhead.
Linux has enforced a minimal value of 48. Since this value includes
the size of TCP options, and that the options can consume up to 40
bytes, this means that each segment can include only 8 bytes of payload.
In some cases, it can be useful to increase the minimal value
to a saner value.
We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility
reasons.
Note that TCP_MAXSEG socket option enforces a minimal value
of (TCP_MIN_MSS). David Miller increased this minimal value
in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.")
from 64 to 88.
We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS.
CVE-2019-11479 -- tcp mss hardcoded to 48
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit f070ef2ac66716357066b683fb0baf55f8191a2e upstream.
Jonathan Looney reported that a malicious peer can force a sender
to fragment its retransmit queue into tiny skbs, inflating memory
usage and/or overflow 32bit counters.
TCP allows an application to queue up to sk_sndbuf bytes,
so we need to give some allowance for non malicious splitting
of retransmit queue.
A new SNMP counter is added to monitor how many times TCP
did not allow to split an skb if the allowance was exceeded.
Note that this counter might increase in the case applications
use SO_SNDBUF socket option to lower sk_sndbuf.
CVE-2019-11478 : tcp_fragment, prevent fragmenting a packet when the
socket is already using more than half the allowed space
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff upstream.
Jonathan Looney reported that TCP can trigger the following crash
in tcp_shifted_skb() :
BUG_ON(tcp_skb_pcount(skb) < pcount);
This can happen if the remote peer has advertized the smallest
MSS that linux TCP accepts : 48
An skb can hold 17 fragments, and each fragment can hold 32KB
on x86, or 64KB on PowerPC.
This means that the 16bit witdh of TCP_SKB_CB(skb)->tcp_gso_segs
can overflow.
Note that tcp_sendmsg() builds skbs with less than 64KB
of payload, so this problem needs SACK to be enabled.
SACK blocks allow TCP to coalesce multiple skbs in the retransmit
queue, thus filling the 17 fragments to maximal capacity.
CVE-2019-11477 -- u16 overflow of TCP_SKB_CB(skb)->tcp_gso_segs
Backport notes, provided by Joao Martins <joao.m.martins@oracle.com>
v4.15 or since commit 737ff314563 ("tcp: use sequence distance to
detect reordering") had switched from the packet-based FACK tracking and
switched to sequence-based.
v4.14 and older still have the old logic and hence on
tcp_skb_shift_data() needs to retain its original logic and have
@fack_count in sync. In other words, we keep the increment of pcount with
tcp_skb_pcount(skb) to later used that to update fack_count. To make it
more explicit we track the new skb that gets incremented to pcount in
@next_pcount, and we get to avoid the constant invocation of
tcp_skb_pcount(skb) all together.
Fixes: 832d11c5cd07 ("tcp: Try to restore large SKBs while SACK processing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 89a4aac0ab0e6f5eea10d7bf4869dd15c3de2cd4 upstream.
In the case of a normal sync update, the preparation of framebuffers (be
it calling drm_atomic_helper_prepare_planes() or doing setups with
drm_framebuffer_get()) are performed in the new_state and the respective
cleanups are performed in the old_state.
In the case of async updates, the preparation is also done in the
new_state but the cleanups are done in the new_state (because updates
are performed in place, i.e. in the current state).
The current code blocks async udpates when the fb is changed, turning
async updates into sync updates, slowing down cursor updates and
introducing regressions in igt tests with errors of type:
"CRITICAL: completed 97 cursor updated in a period of 30 flips, we
expect to complete approximately 15360 updates, with the threshold set
at 7680"
Fb changes in async updates were prevented to avoid the following scenario:
- Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1
- Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2
- Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 (wrong)
Where we have a single call to prepare fb2 but double cleanup call to fb2.
To solve the above problems, instead of blocking async fb changes, we
place the old framebuffer in the new_state object, so when the code
performs cleanups in the new_state it will cleanup the old_fb and we
will have the following scenario instead:
- Async update, oldfb = NULL, newfb = fb1, prepare fb1, no cleanup
- Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb1
- Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2
Where calls to prepare/cleanup are balanced.
Cc: <stable@vger.kernel.org> # v4.14+
Fixes: 25dc194b34dd ("drm: Block fb changes for async plane updates")
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190603165610.24614-6-helen.koike@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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connections"
This reverts commit 2fa7a155b25160696cd77cdd995536cf5e172e20 which is
commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.
Lots of people have reported issues with this patch, and as there does
not seem to be a fix going into Linus's kernel tree any time soon,
revert the commit in the stable trees so as to get people's machines
working properly again.
Reported-by: Vasily Khoruzhick <anarsoul@gmail.com>
Reported-by: Hans de Goede <hdegoede@redhat.com>
Cc: Jeremy Cline <jeremy@jcline.org>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 347ab9480313737c0f1aaa08e8f2e1a791235535 ]
This patch fixes deadlock warning if removing PWM device
when CONFIG_PROVE_LOCKING is enabled.
This issue can be reproceduced by the following steps on
the R-Car H3 Salvator-X board if the backlight is disabled:
# cd /sys/class/pwm/pwmchip0
# echo 0 > export
# ls
device export npwm power pwm0 subsystem uevent unexport
# cd device/driver
# ls
bind e6e31000.pwm uevent unbind
# echo e6e31000.pwm > unbind
[ 87.659974] ======================== |
