[ Upstream commit 29eb315427 ]
ym needs to be free when ym->cmd != SIOCYAMSMCS.
Fixes: 0781168e23 ("yam: fix a missing-check bug")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
commit efe4186e6a upstream.
When a 6pack device is detaching, the sixpack_close() will act to cleanup
necessary resources. Although del_timer_sync() in sixpack_close()
won't return if there is an active timer, one could use mod_timer() in
sp_xmit_on_air() to wake up timer again by calling userspace syscall such
as ax25_sendmsg(), ax25_connect() and ax25_ioctl().
This unexpected waked handler, sp_xmit_on_air(), realizes nothing about
the undergoing cleanup and may still call pty_write() to use driver layer
resources that have already been released.
One of the possible race conditions is shown below:
(USE) | (FREE)
ax25_sendmsg() |
ax25_queue_xmit() |
... |
sp_xmit() |
sp_encaps() | sixpack_close()
sp_xmit_on_air() | del_timer_sync(&sp->tx_t)
mod_timer(&sp->tx_t,...) | ...
| unregister_netdev()
| ...
(wait a while) | tty_release()
| tty_release_struct()
| release_tty()
sp_xmit_on_air() | tty_kref_put(tty_struct) //FREE
pty_write(tty_struct) //USE | ...
The corresponding fail log is shown below:
===============================================================
BUG: KASAN: use-after-free in __run_timers.part.0+0x170/0x470
Write of size 8 at addr ffff88800a652ab8 by task swapper/2/0
...
Call Trace:
...
queue_work_on+0x3f/0x50
pty_write+0xcd/0xe0pty_write+0xcd/0xe0
sp_xmit_on_air+0xb2/0x1f0
call_timer_fn+0x28/0x150
__run_timers.part.0+0x3c2/0x470
run_timer_softirq+0x3b/0x80
__do_softirq+0xf1/0x380
...
This patch reorders the del_timer_sync() after the unregister_netdev()
to avoid UAF bugs. Because the unregister_netdev() is well synchronized,
it flushs out any pending queues, waits the refcount of net_device
decreases to zero and removes net_device from kernel. There is not any
running routines after executing unregister_netdev(). Therefore, we could
not arouse timer from userspace again.
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
[ Upstream commit 04d80663f6 ]
Currently, with an unknown recv_type, mwifiex_usb_recv
just return -1 without restoring the skb. Next time
mwifiex_usb_rx_complete is invoked with the same skb,
calling skb_put causes skb_over_panic.
The bug is triggerable with a compromised/malfunctioning
usb device. After applying the patch, skb_over_panic
no longer shows up with the same input.
Attached is the panic report from fuzzing.
skbuff: skb_over_panic: text:000000003bf1b5fa
len:2048 put:4 head:00000000dd6a115b data:000000000a9445d8
tail:0x844 end:0x840 dev:<NULL>
kernel BUG at net/core/skbuff.c:109!
invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 PID: 198 Comm: in:imklog Not tainted 5.6.0 #60
RIP: 0010:skb_panic+0x15f/0x161
Call Trace:
<IRQ>
? mwifiex_usb_rx_complete+0x26b/0xfcd [mwifiex_usb]
skb_put.cold+0x24/0x24
mwifiex_usb_rx_complete+0x26b/0xfcd [mwifiex_usb]
__usb_hcd_giveback_urb+0x1e4/0x380
usb_giveback_urb_bh+0x241/0x4f0
? __hrtimer_run_queues+0x316/0x740
? __usb_hcd_giveback_urb+0x380/0x380
tasklet_action_common.isra.0+0x135/0x330
__do_softirq+0x18c/0x634
irq_exit+0x114/0x140
smp_apic_timer_interrupt+0xde/0x380
apic_timer_interrupt+0xf/0x20
</IRQ>
Reported-by: Brendan Dolan-Gavitt <brendandg@nyu.edu>
Signed-off-by: Zekun Shen <bruceshenzk@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/YX4CqjfRcTa6bVL+@Zekuns-MBP-16.fios-router.home
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
commit be81992f90 upstream.
In case a guest isn't consuming incoming network traffic as fast as it
is coming in, xen-netback is buffering network packages in unlimited
numbers today. This can result in host OOM situations.
Commit f48da8b14d ("xen-netback: fix unlimited guest Rx internal
queue and carrier flapping") meant to introduce a mechanism to limit
the amount of buffered data by stopping the Tx queue when reaching the
data limit, but this doesn't work for cases like UDP.
When hitting the limit don't queue further SKBs, but drop them instead.
In order to be able to tell Rx packages have been dropped increment the
rx_dropped statistics counter in this case.
It should be noted that the old solution to continue queueing SKBs had
the additional problem of an overflow of the 32-bit rx_queue_len value
would result in intermittent Tx queue enabling.
This is part of XSA-392
Fixes: f48da8b14d ("xen-netback: fix unlimited guest Rx internal queue and carrier flapping")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
commit 6032046ec4 upstream.
Commit 1d5d485239 ("xen-netback: require fewer guest Rx slots when
not using GSO") introduced a security problem in netback, as an
interface would only be regarded to be stalled if no slot is available
in the rx queue ring page. In case the SKB at the head of the queued
requests will need more than one rx slot and only one slot is free the
stall detection logic will never trigger, as the test for that is only
looking for at least one slot to be free.
Fix that by testing for the needed number of slots instead of only one
slot being available.
In order to not have to take the rx queue lock that often, store the
number of needed slots in the queue data. As all SKB dequeue operations
happen in the rx queue kernel thread this is safe, as long as the
number of needed slots is accessed via READ/WRITE_ONCE() only and
updates are always done with the rx queue lock held.
Add a small helper for obtaining the number of free slots.
This is part of XSA-392
Fixes: 1d5d485239 ("xen-netback: require fewer guest Rx slots when not using GSO")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
[ Upstream commit 481221775d ]
Zero-initialize memory for new map's value in function nsim_bpf_map_alloc
since it may cause a potential kernel information leak issue, as follows:
1. nsim_bpf_map_alloc calls nsim_map_alloc_elem to allocate elements for
a new map.
2. nsim_map_alloc_elem uses kmalloc to allocate map's value, but doesn't
zero it.
3. A user application can use IOCTL BPF_MAP_LOOKUP_ELEM to get specific
element's information in the map.
4. The kernel function map_lookup_elem will call bpf_map_copy_value to get
the information allocated at step-2, then use copy_to_user to copy to the
user buffer.
This can only leak information for an array map.
Fixes: 395cacb5f1 ("netdevsim: bpf: support fake map offload")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Haimin Zhang <tcs.kernel@gmail.com>
Link: https://lore.kernel.org/r/20211215111530.72103-1-tcs.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Honglin Li <honglinli@tencent.com>
commit 38fa5479b4 upstream
fix CVE-2022-36123
The .brk section has the same properties as .bss: it is an alloc-only
section and should be cleared before being used.
Not doing so is especially a problem for Xen PV guests, as the
hypervisor will validate page tables (check for writable page tables
and hypervisor private bits) before accepting them to be used.
Make sure .brk is initially zero by letting clear_bss() clear the brk
area, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220630071441.28576-3-jgross@suse.com
Signed-off-by: Xinghui Li <korantli@tencent.com>
commit 00b5f37189 upstream
fix CVE-2022-2153
When kvm_irq_delivery_to_apic_fast() is called with APIC_DEST_SELF
shorthand, 'src' must not be NULL. Crash the VM with KVM_BUG_ON()
instead of crashing the host.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220325132140.25650-3-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Xinghui Li <korantli@tencent.com>
commit 9f46c187e2 upstream.
fix CVE-2022-1789
With shadow paging enabled, the INVPCID instruction results in a call
to kvm_mmu_invpcid_gva. If INVPCID is executed with CR0.PG=0, the
invlpg callback is not set and the result is a NULL pointer dereference.
Fix it trivially by checking for mmu->invlpg before every call.
There are other possibilities:
- check for CR0.PG, because KVM (like all Intel processors after P5)
flushes guest TLB on CR0.PG changes so that INVPCID/INVLPG are a
nop with paging disabled
- check for EFER.LMA, because KVM syncs and flushes when switching
MMU contexts outside of 64-bit mode
All of these are tricky, go for the simple solution. This is CVE-2022-1789.
Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Xinghui Li <korantli@tencent.com>
commit 046545a661 upstream.
When an uncorrected memory error is consumed there is a race between the CMCI from the memory controller reporting an uncorrected error with a UCNA signature, and the core reporting and SRAR signature machine check when the data is about to be consumed.
If the CMCI wins that race, the page is marked poisoned when
uc_decode_notifier() calls memory_failure() and the machine check processing code finds the page already poisoned. It calls
kill_accessing_process() to make sure a SIGBUS is sent. But returns the wrong error code.
Console log looks like this:
[34775.674296] mce: Uncorrected hardware memory error in user-access at 3710b3400 [34775.675413] Memory failure: 0x3710b3: recovery action for dirty LRU page: Recovered [34775.690310] Memory failure: 0x3710b3: already hardware poisoned [34775.696247] Memory failure: 0x3710b3: Sending SIGBUS to einj_mem_uc:361438 due to hardware memory corruption [34775.706072] mce: Memory error not recovered
kill_accessing_process() is supposed to return -EHWPOISON to notify that SIGBUS is already set to the process and kill_me_maybe() doesn't have to send it again. But current code simply fails to do this, so fix it to make sure to work as intended. This change avoids the noise message "Memory error not recovered" and skips duplicate SIGBUSs.
[tony.luck@intel.com: reword some parts of commit message]
Link: https://lkml.kernel.org/r/20220113231117.1021405-1-naoya.horiguchi@linux.dev
Fixes: a3f5d80ea4 ("mm,hwpoison: send SIGBUS with error virutal address")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Youquan Song <youquan.song@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 3376136300 upstream.
When any of the copy functions in arch/x86/lib/copy_user_64.S take a
fault, the fixup code copies the remaining byte count from %ecx to %edx
and unconditionally jumps to .Lcopy_user_handle_tail to continue the
copy in case any more bytes can be copied.
If the fault was #PF this may copy more bytes (because the page fault
handler might have fixed the fault). But when the fault is a machine
check the original copy code will have copied all the way to the poisoned
cache line. So .Lcopy_user_handle_tail will just take another machine
check for no good reason.
Every code path to .Lcopy_user_handle_tail comes from an exception fixup
path, so add a check there to check the trap type (in %eax) and simply
return the count of remaining bytes if the trap was a machine check.
Doing this reduces the number of machine checks taken during synthetic
tests from four to three.
As well as reducing the number of machine checks, this also allows
Skylake generation Xeons to recover some cases that currently fail. The
is because REP; MOVSB is only recoverable when source and destination
are well aligned and the byte count is large. That useless call to
.Lcopy_user_handle_tail may violate one or more of these conditions and
generate a fatal machine check.
[ Tony: Add more details to commit message. ]
[ bp: Fixup comment.
Also, another tip patchset which is adding straight-line speculation
mitigation changes the "ret" instruction to an all-caps macro "RET".
But, since gas is case-insensitive, use "RET" in the newly added asm block
already in order to simplify tip branch merging on its way upstream.
]
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/YcTW5dh8yTGucDd+@agluck-desk2.amr.corp.intel.com
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit bc1bb416bb upstream
if we run into a short copy and ->write_end() refuses to advance at all,
use the amount we'd managed to copy for the next iteration to handle.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 690658471b upstream
Fixes to the iterator code to handle faults that are not on page
boundaries mean that the special case for machine check during copy from
user is no longer needed.
For a full list of those fixes, see the output of:
git log --oneline v5.14 ^v5.13 -- lib/iov_iter.c
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210818002942.1607544-4-tony.luck@intel.com
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit a6e3cf70b7 upstream
Sending a SIGBUS for a copy from user is not the correct semantic.
System calls should return -EFAULT (or a short count for write(2)).
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210818002942.1607544-3-tony.luck@intel.com
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 81065b35e2 upstream
There are two cases for machine check recovery:
1) The machine check was triggered by ring3 (application) code.
This is the simpler case. The machine check handler simply queues
work to be executed on return to user. That code unmaps the page
from all users and arranges to send a SIGBUS to the task that
triggered the poison.
2) The machine check was triggered in kernel code that is covered by
an exception table entry. In this case the machine check handler
still queues a work entry to unmap the page, etc. but this will
not be called right away because the #MC handler returns to the
fix up code address in the exception table entry.
Problems occur if the kernel triggers another machine check before the
return to user processes the first queued work item.
Specifically, the work is queued using the ->mce_kill_me callback
structure in the task struct for the current thread. Attempting to queue
a second work item using this same callback results in a loop in the
linked list of work functions to call. So when the kernel does return to
user, it enters an infinite loop processing the same entry for ever.
There are some legitimate scenarios where the kernel may take a second
machine check before returning to the user.
1) Some code (e.g. futex) first tries a get_user() with page faults
disabled. If this fails, the code retries with page faults enabled
expecting that this will resolve the page fault.
2) Copy from user code retries a copy in byte-at-time mode to check
whether any additional bytes can be copied.
On the other side of the fence are some bad drivers that do not check
the return value from individual get_user() calls and may access
multiple user addresses without noticing that some/all calls have
failed.
Fix by adding a counter (current->mce_count) to keep track of repeated
machine checks before task_work() is called. First machine check saves
the address information and calls task_work_add(). Subsequent machine
checks before that task_work call back is executed check that the address
is in the same page as the first machine check (since the callback will
offline exactly one page).
Expected worst case is four machine checks before moving on (e.g. one
user access with page faults disabled, then a repeat to the same address
with page faults enabled ... repeat in copy tail bytes). Just in case
there is some code that loops forever enforce a limit of 10.
[ bp: Massage commit message, drop noinstr, fix typo, extend panic
messages. ]
Fixes: 5567d11c21 ("x86/mce: Send #MC singal from task work")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/YT/IJ9ziLqmtqEPu@agluck-desk2.amr.corp.intel.com
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit cf4e6d52f5 upstream
Retrieve and print retry_rd_err_log registers like the earlier change:
commit e80634a75a ("EDAC, skx: Retrieve and print retry_rd_err_log registers")
This is a little trickier than on Skylake because of potential
interference with BIOS use of the same registers. The default
behavior is to ignore these registers.
A module parameter retry_rd_err_log(default=0) controls the mode of operation:
- 0=off : Default.
- 1=bios : Linux doesn't reset any control bits, but just reports values.
This is "no harm" mode, but it may miss reporting some data.
- 2=linux: Linux tries to take control and resets mode bits,
clears valid/UC bits after reading. This should be
more reliable (especially if BIOS interference is reduced
by disabling eMCA reporting mode in BIOS setup).
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20210818175701.1611513-3-tony.luck@intel.com
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
compare to down_read_killable, down_read is better and closer to
upstream newer function mmap_read_lock semantic.
The issues backporting patch:
mm,hwpoison: send SIGBUS with error virutal address
commit a3f5d80ea4 upstream
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit a3f5d80ea4 upstream
Now an action required MCE in already hwpoisoned address surely sends a
SIGBUS to current process, but the SIGBUS doesn't convey error virtual
address. That's not optimal for hwpoison-aware applications.
To fix the issue, make memory_failure() call kill_accessing_process(),
that does pagetable walk to find the error virtual address. It could find
multiple virtual addresses for the same error page, and it seems hard to
tell which virtual address is correct one. But that's rare and sending
incorrect virtual address could be better than no address. So let's
report the first found virtual address for now.
[naoya.horiguchi@nec.com: fix walk_page_range() return]
Link: https://lkml.kernel.org/r/20210603051055.GA244241@hori.linux.bs1.fc.nec.co.jp
Link: https://lkml.kernel.org/r/20210521030156.2612074-4-nao.horiguchi@gmail.com
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Aili Yao <yaoaili@kingsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jue Wang <juew@google.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit ea6d063010 upstream
Currently me_huge_page() temporary unlocks page to perform some actions
then locks it again later. My testcase (which calls hard-offline on
some tail page in a hugetlb, then accesses the address of the hugetlb
range) showed that page allocation code detects this page lock on buddy
page and printed out "BUG: Bad page state" message.
check_new_page_bad() does not consider a page with __PG_HWPOISON as bad
page, so this flag works as kind of filter, but this filtering doesn't
work in this case because the "bad page" is not the actual hwpoisoned
page. So stop locking page again. Actions to be taken depend on the
page type of the error, so page unlocking should be done in ->action()
callbacks. So let's make it assumed and change all existing callbacks
that way.
Link: https://lkml.kernel.org/r/20210609072029.74645-1-nao.horiguchi@gmail.com
Fixes: commit 78bb920344 ("mm: hwpoison: dissolve in-use hugepage in unrecoverable memory error")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.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: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 47af12bae1 upstream
When memory_failure() is called with MF_ACTION_REQUIRED on the page that
has already been hwpoisoned, memory_failure() could fail to send SIGBUS
to the affected process, which results in infinite loop of MCEs.
Currently memory_failure() returns 0 if it's called for already
hwpoisoned page, then the caller, kill_me_maybe(), could return without
sending SIGBUS to current process. An action required MCE is raised
when the current process accesses to the broken memory, so no SIGBUS
means that the current process continues to run and access to the error
page again soon, so running into MCE loop.
This issue can arise for example in the following scenarios:
- Two or more threads access to the poisoned page concurrently. If
local MCE is enabled, MCE handler independently handles the MCE
events. So there's a race among MCE events, and the second or latter
threads fall into the situation in question.
- If there was a precedent memory error event and memory_failure() for
the event failed to unmap the error page for some reason, the
subsequent memory access to the error page triggers the MCE loop
situation.
To fix the issue, make memory_failure() return an error code when the
error page has already been hwpoisoned. This allows memory error
handler to control how it sends signals to userspace. And make sure
that any process touching a hwpoisoned page should get a SIGBUS even in
"already hwpoisoned" path of memory_failure() as is done in page fault
path.
Link: https://lkml.kernel.org/r/20210521030156.2612074-3-nao.horiguchi@gmail.com
Signed-off-by: Aili Yao <yaoaili@kingsoft.com>
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jue Wang <juew@google.com>
Cc: Tony Luck <tony.luck@intel.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: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 171936ddaf upstream
Patch series "mm,hwpoison: fix sending SIGBUS for Action Required MCE", v5.
I wrote this patchset to materialize what I think is the current
allowable solution mentioned by the previous discussion [1]. I simply
borrowed Tony's mutex patch and Aili's return code patch, then I queued
another one to find error virtual address in the best effort manner. I
know that this is not a perfect solution, but should work for some
typical case.
[1]: https://lore.kernel.org/linux-mm/20210331192540.2141052f@alex-virtual-machine/
This patch (of 2):
There can be races when multiple CPUs consume poison from the same page.
The first into memory_failure() atomically sets the HWPoison page flag
and begins hunting for tasks that map this page. Eventually it
invalidates those mappings and may send a SIGBUS to the affected tasks.
But while all that work is going on, other CPUs see a "success" return
code from memory_failure() and so they believe the error has been
handled and continue executing.
Fix by wrapping most of the internal parts of memory_failure() in a
mutex.
[akpm@linux-foundation.org: make mf_mutex local to memory_failure()]
Link: https://lkml.kernel.org/r/20210521030156.2612074-1-nao.horiguchi@gmail.com
Link: https://lkml.kernel.org/r/20210521030156.2612074-2-nao.horiguchi@gmail.com
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Aili Yao <yaoaili@kingsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jue Wang <juew@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: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 8438b84ab4 upstream
Commit
fa92c58694 ("x86, mce: Support memory error recovery for both UCNA
and Deferred error in machine_check_poll")
added handling of UCNA and Deferred errors by adding them to the ring
for SRAO errors.
Later, commit
fd4cf79fcc ("x86/mce: Remove the MCE ring for Action Optional errors")
switched storage from the SRAO ring to the unified pool that is still
in use today. In order to only act on the intended errors, a filter
for MCE_AO_SEVERITY is used -- effectively removing handling of
UCNA/Deferred errors again.
Extend the severity filter to include UCNA/Deferred errors again.
Also, generalize the naming of the notifier from SRAO to UC to capture
the extended scope.
Note, that this change may cause a message like the following to appear,
as the same address may be reported as SRAO and as UCNA:
Memory failure: 0x5fe3284: already hardware poisoned
Technically, this is a return to previous behavior.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200103150722.20313-2-jschoenh@amazon.de
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit 8c4e93c362 upstream
There is plenty of space in the printk_context variable. Reserve one byte
there for the NMI context to be on the safe side.
It should never overflow. The BUG_ON(in_nmi() == NMI_MASK) in nmi_enter()
will trigger much earlier.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Link: https://lkml.kernel.org/r/20200505134100.681374113@linutronix.de
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
commit a501ab75e7 upstream.
There is a race in pty_write(). pty_write() can be called in parallel
with e.g. ioctl(TIOCSTI) or ioctl(TCXONC) which also inserts chars to
the buffer. Provided, tty_flip_buffer_push() in pty_write() is called
outside the lock, it can commit inconsistent tail. This can lead to out
of bounds writes and other issues. See the Link below.
To fix this, we have to introduce a new helper called
tty_insert_flip_string_and_push_buffer(). It does both
tty_insert_flip_string() and tty_flip_buffer_commit() under the port
lock. It also calls queue_work(), but outside the lock. See
71a174b39f (pty: do tty_flip_buffer_push without port->lock in
pty_write) for the reasons.
Keep the helper internal-only (in drivers' tty.h). It is not intended to
be used widely.
Link: https://seclists.org/oss-sec/2022/q2/155
Fixes: 71a174b39f (pty: do tty_flip_buffer_push without port->lock in pty_write)
Cc: 一只狗 <chennbnbnb@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220707082558.9250-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 716b105802 upstream.
We will need this new helper in the next patch.
Cc: Hillf Danton <hdanton@sina.com>
Cc: 一只狗 <chennbnbnb@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220707082558.9250-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 5db96ef23b upstream.
Since commit a9c3f68f3c (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). All
users were converted in the previous patches, so remove
tty_schedule_flip() completely while inlining its body into
tty_flip_buffer_push().
One less exported function.
For kabi compatibility, we don't drop tty_schedule_flip(), only modify
tty_flip_buffer_push() in our tk4.
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20211122111648.30379-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 8e12784444 upstream.
powerpc/32: Fix overread/overwrite of thread_struct via ptrace
The ptrace PEEKUSR/POKEUSR (aka PEEKUSER/POKEUSER) API allows a process
to read/write registers of another process.
To get/set a register, the API takes an index into an imaginary address
space called the "USER area", where the registers of the process are
laid out in some fashion.
The kernel then maps that index to a particular register in its own data
structures and gets/sets the value.
The API only allows a single machine-word to be read/written at a time.
So 4 bytes on 32-bit kernels and 8 bytes on 64-bit kernels.
The way floating point registers (FPRs) are addressed is somewhat
complicated, because double precision float values are 64-bit even on
32-bit CPUs. That means on 32-bit kernels each FPR occupies two
word-sized locations in the USER area. On 64-bit kernels each FPR
occupies one word-sized location in the USER area.
Internally the kernel stores the FPRs in an array of u64s, or if VSX is
enabled, an array of pairs of u64s where one half of each pair stores
the FPR. Which half of the pair stores the FPR depends on the kernel's
endianness.
To handle the different layouts of the FPRs depending on VSX/no-VSX and
big/little endian, the TS_FPR() macro was introduced.
Unfortunately the TS_FPR() macro does not take into account the fact
that the addressing of each FPR differs between 32-bit and 64-bit
kernels. It just takes the index into the "USER area" passed from
userspace and indexes into the fp_state.fpr array.
On 32-bit there are 64 indexes that address FPRs, but only 32 entries in
the fp_state.fpr array, meaning the user can read/write 256 bytes past
the end of the array. Because the fp_state sits in the middle of the
thread_struct there are various fields than can be overwritten,
including some pointers. As such it may be exploitable.
It has also been observed to cause systems to hang or otherwise
misbehave when using gdbserver, and is probably the root cause of this
report which could not be easily reproduced:
https://lore.kernel.org/linuxppc-dev/dc38afe9-6b78-f3f5-666b-986939e40fc6@keymile.com/
Rather than trying to make the TS_FPR() macro even more complicated to
fix the bug, or add more macros, instead add a special-case for 32-bit
kernels. This is more obvious and hopefully avoids a similar bug
happening again in future.
Note that because 32-bit kernels never have VSX enabled the code doesn't
need to consider TS_FPRWIDTH/OFFSET at all. Add a BUILD_BUG_ON() to
ensure that 32-bit && VSX is never enabled.
Fixes: 87fec0514f ("powerpc: PTRACE_PEEKUSR/PTRACE_POKEUSER of FPR registers in little endian builds")
Cc: stable@vger.kernel.org # v3.13+
Reported-by: Ariel Miculas <ariel.miculas@belden.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220609133245.573565-1-mpe@ellerman.id.au
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 4caae58406 upstream.
The device-mapper framework provides a mechanism to mark targets as
immutable (and hence fail table reloads that try to change the target
type). Add the DM_TARGET_IMMUTABLE flag to the dm-verity target's
feature flags to prevent switching the verity target with a different
target type.
Fixes: a4ffc15219 ("dm: add verity target")
Cc: stable@vger.kernel.org
Signed-off-by: Sarthak Kukreti <sarthakkukreti@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 543ce63b66 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: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit d270453a0d upstream.
There are destructive operations such as nfcmrvl_fw_dnld_abort and
gpio_free in nfcmrvl_nci_unregister_dev. The resources such as firmware,
gpio and so on could be destructed while the upper layer functions such as
nfcmrvl_fw_dnld_start and nfcmrvl_nci_recv_frame is executing, which leads
to double-free, use-after-free and null-ptr-deref bugs.
There are three situations that could lead to double-free bugs.
The first situation is shown below:
(Thread 1) | (Thread 2)
nfcmrvl_fw_dnld_start |
... | nfcmrvl_nci_unregister_dev
release_firmware() | nfcmrvl_fw_dnld_abort
kfree(fw) //(1) | fw_dnld_over
| release_firmware
... | kfree(fw) //(2)
| ...
The second situation is shown below:
(Thread 1) | (Thread 2)
nfcmrvl_fw_dnld_start |
... |
mod_timer |
(wait a time) |
fw_dnld_timeout | nfcmrvl_nci_unregister_dev
fw_dnld_over | nfcmrvl_fw_dnld_abort
release_firmware | fw_dnld_over
kfree(fw) //(1) | release_firmware
... | kfree(fw) //(2)
The third situation is shown below:
(Thread 1) | (Thread 2)
nfcmrvl_nci_recv_frame |
if(..->fw_download_in_progress)|
nfcmrvl_fw_dnld_recv_frame |
queue_work |
|
fw_dnld_rx_work | nfcmrvl_nci_unregister_dev
fw_dnld_over | nfcmrvl_fw_dnld_abort
release_firmware | fw_dnld_over
kfree(fw) //(1) | release_firmware
| kfree(fw) //(2)
The firmware struct is deallocated in position (1) and deallocated
in position (2) again.
The crash trace triggered by POC is like below:
BUG: KASAN: double-free or invalid-free in fw_dnld_over
Call Trace:
kfree
fw_dnld_over
nfcmrvl_nci_unregister_dev
nci_uart_tty_close
tty_ldisc_kill
tty_ldisc_hangup
__tty_hangup.part.0
tty_release
...
What's more, there are also use-after-free and null-ptr-deref bugs
in nfcmrvl_fw_dnld_start. If we deallocate firmware struct, gpio or
set null to the members of priv->fw_dnld in nfcmrvl_nci_unregister_dev,
then, we dereference firmware, gpio or the members of priv->fw_dnld in
nfcmrvl_fw_dnld_start, the UAF or NPD bugs will happen.
This patch reorders destructive operations after nci_unregister_device
in order to synchronize between cleanup routine and firmware download
routine.
The nci_unregister_device is well synchronized. If the device is
detaching, the firmware download routine will goto error. If firmware
download routine is executing, nci_unregister_device will wait until
firmware download routine is finished.
Fixes: 3194c68701 ("NFC: nfcmrvl: add firmware download support")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit 3ac6487e58 upstream.
Norbert reported that it's possible to race sys_perf_event_open() such
that the looser ends up in another context from the group leader,
triggering many WARNs.
The move_group case checks for races against itself, but the
!move_group case doesn't, seemingly relying on the previous
group_leader->ctx == ctx check. However, that check is racy due to not
holding any locks at that time.
Therefore, re-check the result after acquiring locks and bailing
if they no longer match.
Additionally, clarify the not_move_group case from the
move_group-vs-move_group race.
Fixes: f63a8daa58 ("perf: Fix event->ctx locking")
Reported-by: Norbert Slusarek <nslusarek@gmx.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
commit eadb2f47a3 upstream.
KGDB and KDB allow read and write access to kernel memory, and thus
should be restricted during lockdown. An attacker with access to a
serial port (for example, via a hypervisor console, which some cloud
vendors provide over the network) could trigger the debugger so it is
important that the debugger respect the lockdown mode when/if it is
triggered.
Fix this by integrating lockdown into kdb's existing permissions
mechanism. Unfortunately kgdb does not have any permissions mechanism
(although it certainly could be added later) so, for now, kgdb is simply
and brutally disabled by immediately exiting the gdb stub without taking
any action.
For lockdowns established early in the boot (e.g. the normal case) then
this should be fine but on systems where kgdb has set breakpoints before
the lockdown is enacted than "bad things" will happen.
CVE: CVE-2022-21499
Co-developed-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tao Wu <tallwu@tencent.com>
Reviewed-by: Alex Shi <alexsshi@tencent.com>
Commit 42baefac63 upstream.
gnttab_end_foreign_access() is used to free a grant reference and
optionally to free the associated page. In case the grant is still in
use by the other side processing is being deferred. This leads to a
problem in case no page to be freed is specified by the caller: the
caller doesn't know that the page is still mapped by the other side
and thus should not be used for other purposes.
The correct way to handle this situation is to take an additional
reference to the granted page in case handling is being deferred and
to drop that reference when the grant reference could be freed
finally.
This requires that there are no users of gnttab_end_foreign_access()
left directly repurposing the granted page after the call, as this
might result in clobbered data or information leaks via the not yet
freed grant reference.
This is part of CVE-2022-23041 / XSA-396.
Reported-by: Simon Gaiser <simon@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit b0576cc9c6 upstream.
Instead of __get_free_pages() and free_pages() use alloc_pages_exact()
and free_pages_exact(). This is in preparation of a change of
gnttab_end_foreign_access() which will prohibit use of high-order
pages.
This is part of CVE-2022-23041 / XSA-396.
Reported-by: Simon Gaiser <simon@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit 1dbd11ca75 upstream.
Remove gnttab_query_foreign_access(), as it is unused and unsafe to
use.
All previous use cases assumed a grant would not be in use after
gnttab_query_foreign_access() returned 0. This information is useless
in best case, as it only refers to a situation in the past, which could
have changed already.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit 33172ab50a upstream.
It isn't enough to check whether a grant is still being in use by
calling gnttab_query_foreign_access(), as a mapping could be realized
by the other side just after having called that function.
In case the call was done in preparation of revoking a grant it is
better to do so via gnttab_try_end_foreign_access() and check the
success of that operation instead.
This is CVE-2022-23038 / part of XSA-396.
Reported-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit 4491001c2e upstream.
Bounce all data on the skbs to be transmitted into zeroed pages if the
backend is untrusted. This avoids leaking data present in the pages
shared with the backend but not part of the skb fragments. This
requires introducing a new helper in order to allocate skbs with a
size multiple of XEN_PAGE_SIZE so we don't leak contiguous data on the
granted pages.
Reporting whether the backend is to be trusted can be done using a
module parameter, or from the xenstore frontend path as set by the
toolstack when adding the device.
This is CVE-2022-33741, part of XSA-403.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit 307c8de2b0 upstream.
When allocating pages to be used for shared communication with the
backend always zero them, this avoids leaking unintended data present
on the pages.
This is CVE-2022-33740, part of XSA-403.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit 66e3531b33 upstream.
When calling gnttab_end_foreign_access_ref() the returned value must
be tested and the reaction to that value should be appropriate.
In case of failure in xennet_get_responses() the reaction should not be
to crash the system, but to disable the network device.
The calls in setup_netfront() can be replaced by calls of
gnttab_end_foreign_access(). While at it avoid double free of ring
pages and grant references via xennet_disconnect_backend() in this case.
This is CVE-2022-23042 / part of XSA-396.
Reported-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit 31185df7e2 upstream.
It isn't enough to check whether a grant is still being in use by
calling gnttab_query_foreign_access(), as a mapping could be realized
by the other side just after having called that function.
In case the call was done in preparation of revoking a grant it is
better to do so via gnttab_end_foreign_access_ref() and check the
success of that operation instead.
This is CVE-2022-23037 / part of XSA-396.
Reported-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit b27d47950e upstream.
The Xen netfront driver is still vulnerable for an attack via excessive
number of events sent by the backend. Fix that by using lateeoi event
channels.
For being able to detect the case of no rx responses being added while
the carrier is down a new lock is needed in order to update and test
rsp_cons and the number of seen unconsumed responses atomically.
This is part of XSA-391
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit a884daa61a upstream.
Today netfront will trust the backend to send only sane response data.
In order to avoid privilege escalations or crashes in case of malicious
backends verify the data to be within expected limits. Especially make
sure that the response always references an outstanding request.
Note that only the tx queue needs special id handling, as for the rx
queue the id is equal to the index in the ring page.
Introduce a new indicator for the device whether it is broken and let
the device stop working when it is set. Set this indicator in case the
backend sets any weird data.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit 21631d2d74 upstream.
The tx_skb_freelist elements are in a single linked list with the
request id used as link reference. The per element link field is in a
union with the skb pointer of an in use request.
Move the link reference out of the union in order to enable a later
reuse of it for requests which need a populated skb pointer.
Rename add_id_to_freelist() and get_id_from_freelist() to
add_id_to_list() and get_id_from_list() in order to prepare using
those for other lists as well. Define ~0 as value to indicate the end
of a list and place that value into the link for a request not being
on the list.
When freeing a skb zero the skb pointer in the request. Use a NULL
value of the skb pointer instead of skb_entry_is_link() for deciding
whether a request has a skb linked to it.
Remove skb_entry_set_link() and open code it instead as it is really
trivial now.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit 162081ec33 upstream.
In order to avoid a malicious backend being able to influence the local
processing of a request build the request locally first and then copy
it to the ring page. Any reading from the request influencing the
processing in the frontend needs to be done on the local instance.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
commit 8446066bf8 upstream.
In order to avoid problems in case the backend is modifying a response
on the ring page while the frontend has already seen it, just read the
response into a local buffer in one go and then operate on that buffer
only.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Commit 5cadd4bb1d upstream.
Instead of __get_free_pages() and free_pages() use alloc_pages_exact()
and free_pages_exact(). This is in preparation of a change of
gnttab_end_foreign_access() which will prohibit use of high-order
pages.
By using the local variable "order" instead of ring->intf->ring_order
in the error path of xen_9pfs_front_alloc_dataring() another bug is
fixed, as the error path can be entered before ring->intf->ring_order
is being set.
By using alloc_pages_exact() the size in bytes is specified for the
allocation, which fixes another bug for the case of
order < (PAGE_SHIFT - XEN_PAGE_SHIFT).
This is part of CVE-2022-23041 / XSA-396.
Reported-by: Simon Gaiser <simon@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: samuelliao <samuelliao@tencent.com>
Hangyu Hua