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<title>user/sven/linux.git/include/linux, branch v4.14.281</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2022-05-25T06:41:22Z</updated>
<entry>
<title>Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""</title>
<updated>2022-05-25T06:41:22Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-28T18:37:05Z</published>
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<id>urn:sha1:aaf166f37eb6bb55d81c3e40a2a460c8875c8813</id>
<content type='text'>
commit 901c7280ca0d5e2b4a8929fbe0bfb007ac2a6544 upstream.

Halil Pasic points out [1] that the full revert of that commit (revert
in bddac7c1e02b), and that a partial revert that only reverts the
problematic case, but still keeps some of the cleanups is probably
better.  ￼

And that partial revert [2] had already been verified by Oleksandr
Natalenko to also fix the issue, I had just missed that in the long
discussion.

So let's reinstate the cleanups from commit aa6f8dcbab47 ("swiotlb:
rework "fix info leak with DMA_FROM_DEVICE""), and effectively only
revert the part that caused problems.

Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1]
Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2]
Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3]
Suggested-by: Halil Pasic &lt;pasic@linux.ibm.com&gt;
Tested-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Cc: Christoph Hellwig" &lt;hch@lst.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[OP: backport to 4.14: apply swiotlb_tbl_map_single() changes in lib/swiotlb.c]
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>swiotlb: fix info leak with DMA_FROM_DEVICE</title>
<updated>2022-05-25T06:41:22Z</updated>
<author>
<name>Halil Pasic</name>
<email>pasic@linux.ibm.com</email>
</author>
<published>2022-02-11T01:12:52Z</published>
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<content type='text'>
commit ddbd89deb7d32b1fbb879f48d68fda1a8ac58e8e upstream.

The problem I'm addressing was discovered by the LTP test covering
cve-2018-1000204.

A short description of what happens follows:
1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO
   interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV
   and a corresponding dxferp. The peculiar thing about this is that TUR
   is not reading from the device.
2) In sg_start_req() the invocation of blk_rq_map_user() effectively
   bounces the user-space buffer. As if the device was to transfer into
   it. Since commit a45b599ad808 ("scsi: sg: allocate with __GFP_ZERO in
   sg_build_indirect()") we make sure this first bounce buffer is
   allocated with GFP_ZERO.
3) For the rest of the story we keep ignoring that we have a TUR, so the
   device won't touch the buffer we prepare as if the we had a
   DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device
   and the  buffer allocated by SG is mapped by the function
   virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here
   scatter-gather and not scsi generics). This mapping involves bouncing
   via the swiotlb (we need swiotlb to do virtio in protected guest like
   s390 Secure Execution, or AMD SEV).
4) When the SCSI TUR is done, we first copy back the content of the second
   (that is swiotlb) bounce buffer (which most likely contains some
   previous IO data), to the first bounce buffer, which contains all
   zeros.  Then we copy back the content of the first bounce buffer to
   the user-space buffer.
5) The test case detects that the buffer, which it zero-initialized,
  ain't all zeros and fails.

One can argue that this is an swiotlb problem, because without swiotlb
we leak all zeros, and the swiotlb should be transparent in a sense that
it does not affect the outcome (if all other participants are well
behaved).

Copying the content of the original buffer into the swiotlb buffer is
the only way I can think of to make swiotlb transparent in such
scenarios. So let's do just that if in doubt, but allow the driver
to tell us that the whole mapped buffer is going to be overwritten,
in which case we can preserve the old behavior and avoid the performance
impact of the extra bounce.

Signed-off-by: Halil Pasic &lt;pasic@linux.ibm.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
[OP: backport to 4.14: apply swiotlb_tbl_map_single() changes in lib/swiotlb.c]
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: Fix features skip in for_each_netdev_feature()</title>
<updated>2022-05-18T07:18:05Z</updated>
<author>
<name>Tariq Toukan</name>
<email>tariqt@nvidia.com</email>
</author>
<published>2022-05-04T08:09:14Z</published>
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<id>urn:sha1:39eb33b68f9ca8dbca94771cd8b1d29648229bb3</id>
<content type='text'>
[ Upstream commit 85db6352fc8a158a893151baa1716463d34a20d0 ]

The find_next_netdev_feature() macro gets the "remaining length",
not bit index.
Passing "bit - 1" for the following iteration is wrong as it skips
the adjacent bit. Pass "bit" instead.

Fixes: 3b89ea9c5902 ("net: Fix for_each_netdev_feature on Big endian")
Signed-off-by: Tariq Toukan &lt;tariqt@nvidia.com&gt;
Reviewed-by: Gal Pressman &lt;gal@nvidia.com&gt;
Link: https://lore.kernel.org/r/20220504080914.1918-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>hex2bin: make the function hex_to_bin constant-time</title>
<updated>2022-05-12T10:17:06Z</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2022-04-25T12:07:48Z</published>
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<id>urn:sha1:98d80ee7e50837e601692f5514a81e311c8339ec</id>
<content type='text'>
commit e5be15767e7e284351853cbaba80cde8620341fb upstream.

The function hex2bin is used to load cryptographic keys into device
mapper targets dm-crypt and dm-integrity.  It should take constant time
independent on the processed data, so that concurrently running
unprivileged code can't infer any information about the keys via
microarchitectural convert channels.

This patch changes the function hex_to_bin so that it contains no
branches and no memory accesses.

Note that this shouldn't cause performance degradation because the size
of the new function is the same as the size of the old function (on
x86-64) - and the new function causes no branch misprediction penalties.

I compile-tested this function with gcc on aarch64 alpha arm hppa hppa64
i386 ia64 m68k mips32 mips64 powerpc powerpc64 riscv sh4 s390x sparc32
sparc64 x86_64 and with clang on aarch64 arm hexagon i386 mips32 mips64
powerpc powerpc64 s390x sparc32 sparc64 x86_64 to verify that there are
no branches in the generated code.

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>etherdevice: Adjust ether_addr* prototypes to silence -Wstringop-overead</title>
<updated>2022-04-27T11:15:28Z</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2022-02-12T17:14:49Z</published>
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<id>urn:sha1:ab4d82d4d94f649721b0460948d747a0a5b88ee0</id>
<content type='text'>
commit 2618a0dae09ef37728dab89ff60418cbe25ae6bd upstream.

With GCC 12, -Wstringop-overread was warning about an implicit cast from
char[6] to char[8]. However, the extra 2 bytes are always thrown away,
alignment doesn't matter, and the risk of hitting the edge of unallocated
memory has been accepted, so this prototype can just be converted to a
regular char *. Silences:

net/core/dev.c: In function ‘bpf_prog_run_generic_xdp’: net/core/dev.c:4618:21: warning: ‘ether_addr_equal_64bits’ reading 8 bytes from a region of size 6 [-Wstringop-overread]
 4618 |         orig_host = ether_addr_equal_64bits(eth-&gt;h_dest, &gt; skb-&gt;dev-&gt;dev_addr);
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/core/dev.c:4618:21: note: referencing argument 1 of type ‘const u8[8]’ {aka ‘const unsigned char[8]’}
net/core/dev.c:4618:21: note: referencing argument 2 of type ‘const u8[8]’ {aka ‘const unsigned char[8]’}
In file included from net/core/dev.c:91: include/linux/etherdevice.h:375:20: note: in a call to function ‘ether_addr_equal_64bits’
  375 | static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
      |                    ^~~~~~~~~~~~~~~~~~~~~~~

Reported-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Tested-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Link: https://lore.kernel.org/netdev/20220212090811.uuzk6d76agw2vv73@pengutronix.de
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Khem Raj &lt;raj.khem@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning</title>
<updated>2022-04-20T07:08:30Z</updated>
<author>
<name>Waiman Long</name>
<email>longman@redhat.com</email>
</author>
<published>2022-04-08T20:09:01Z</published>
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<id>urn:sha1:45ac758ee0eec41bed41434dc800d698ac912fbf</id>
<content type='text'>
commit a431dbbc540532b7465eae4fc8b56a85a9fc7d17 upstream.

The gcc 12 compiler reports a "'mem_section' will never be NULL" warning
on the following code:

    static inline struct mem_section *__nr_to_section(unsigned long nr)
    {
    #ifdef CONFIG_SPARSEMEM_EXTREME
        if (!mem_section)
                return NULL;
    #endif
        if (!mem_section[SECTION_NR_TO_ROOT(nr)])
                return NULL;
       :

It happens with CONFIG_SPARSEMEM_EXTREME off.  The mem_section definition
is

    #ifdef CONFIG_SPARSEMEM_EXTREME
    extern struct mem_section **mem_section;
    #else
    extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
    #endif

In the !CONFIG_SPARSEMEM_EXTREME case, mem_section is a static
2-dimensional array and so the check "!mem_section[SECTION_NR_TO_ROOT(nr)]"
doesn't make sense.

Fix this warning by moving the "!mem_section[SECTION_NR_TO_ROOT(nr)]"
check up inside the CONFIG_SPARSEMEM_EXTREME block and adding an
explicit NR_SECTION_ROOTS check to make sure that there is no
out-of-bound array access.

Link: https://lkml.kernel.org/r/20220331180246.2746210-1-longman@redhat.com
Fixes: 3e347261a80b ("sparsemem extreme implementation")
Signed-off-by: Waiman Long &lt;longman@redhat.com&gt;
Reported-by: Justin Forbes &lt;jforbes@redhat.com&gt;
Cc: "Kirill A . Shutemov" &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Rafael Aquini &lt;aquini@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>NFS: swap IO handling is slightly different for O_DIRECT IO</title>
<updated>2022-04-20T07:08:28Z</updated>
<author>
<name>NeilBrown</name>
<email>neilb@suse.de</email>
</author>
<published>2022-03-06T23:41:44Z</published>
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<id>urn:sha1:4e70b56438166c327301152776b0311374c936ee</id>
<content type='text'>
[ Upstream commit 64158668ac8b31626a8ce48db4cad08496eb8340 ]

1/ Taking the i_rwsem for swap IO triggers lockdep warnings regarding
   possible deadlocks with "fs_reclaim".  These deadlocks could, I believe,
   eventuate if a buffered read on the swapfile was attempted.

   We don't need coherence with the page cache for a swap file, and
   buffered writes are forbidden anyway.  There is no other need for
   i_rwsem during direct IO.  So never take it for swap_rw()

2/ generic_write_checks() explicitly forbids writes to swap, and
   performs checks that are not needed for swap.  So bypass it
   for swap_rw().

Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Signed-off-by: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>PCI: Reduce warnings on possible RW1C corruption</title>
<updated>2022-04-20T07:08:18Z</updated>
<author>
<name>Mark Tomlinson</name>
<email>mark.tomlinson@alliedtelesis.co.nz</email>
</author>
<published>2020-08-06T04:14:55Z</published>
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<id>urn:sha1:1c63f5ab2d5bd5ac606d4f5576f732d9fa704747</id>
<content type='text'>
[ Upstream commit 92c45b63ce22c8898aa41806e8d6692bcd577510 ]

For hardware that only supports 32-bit writes to PCI there is the
possibility of clearing RW1C (write-one-to-clear) bits. A rate-limited
messages was introduced by fb2659230120, but rate-limiting is not the best
choice here. Some devices may not show the warnings they should if another
device has just produced a bunch of warnings. Also, the number of messages
can be a nuisance on devices which are otherwise working fine.

Change the ratelimit to a single warning per bus. This ensures no bus is
'starved' of emitting a warning and also that there isn't a continuous
stream of warnings. It would be preferable to have a warning per device,
but the pci_dev structure is not available here, and a lookup from devfn
would be far too slow.

Suggested-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Fixes: fb2659230120 ("PCI: Warn on possible RW1C corruption for sub-32 bit config writes")
Link: https://lore.kernel.org/r/20200806041455.11070-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Mark Tomlinson &lt;mark.tomlinson@alliedtelesis.co.nz&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Reviewed-by: Rob Herring &lt;robh@kernel.org&gt;
Acked-by: Scott Branden &lt;scott.branden@broadcom.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>block: Add a helper to validate the block size</title>
<updated>2022-04-20T07:08:08Z</updated>
<author>
<name>Xie Yongji</name>
<email>xieyongji@bytedance.com</email>
</author>
<published>2021-10-26T14:40:12Z</published>
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<id>urn:sha1:cb55a760a24b1458e856141c43922e88bd1fbcd8</id>
<content type='text'>
commit 570b1cac477643cbf01a45fa5d018430a1fddbce upstream.

There are some duplicated codes to validate the block
size in block drivers. This limitation actually comes
from block layer, so this patch tries to add a new block
layer helper for that.

Signed-off-by: Xie Yongji &lt;xieyongji@bytedance.com&gt;
Link: https://lore.kernel.org/r/20211026144015.188-2-xieyongji@bytedance.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>netdevice: add the case if dev is NULL</title>
<updated>2022-04-20T07:08:08Z</updated>
<author>
<name>Yajun Deng</name>
<email>yajun.deng@linux.dev</email>
</author>
<published>2021-08-05T11:54:34Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=46291a4f2cdb817a7f7c991a9ec0d7a3882c2421'/>
<id>urn:sha1:46291a4f2cdb817a7f7c991a9ec0d7a3882c2421</id>
<content type='text'>
commit b37a466837393af72fe8bcb8f1436410f3f173f3 upstream.

Add the case if dev is NULL in dev_{put, hold}, so the caller doesn't
need to care whether dev is NULL or not.

Signed-off-by: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Pavel Machek &lt;pavel@denx.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
