linux-stable.git/Documentation, branch linux-4.9.y

arm64: errata: Remove AES hwcap for COMPAT tasks

2022-11-03T14:49:15+00:00

commit 44b3834b2eed595af07021b1c64e6f9bc396398b upstream.

Cortex-A57 and Cortex-A72 have an erratum where an interrupt that
occurs between a pair of AES instructions in aarch32 mode may corrupt
the ELR. The task will subsequently produce the wrong AES result.

The AES instructions are part of the cryptographic extensions, which are
optional. User-space software will detect the support for these
instructions from the hwcaps. If the platform doesn't support these
instructions a software implementation should be used.

Remove the hwcap bits on affected parts to indicate user-space should
not use the AES instructions.

Acked-by: Ard Biesheuvel 
Signed-off-by: James Morse 
Link: https://lore.kernel.org/r/20220714161523.279570-3-james.morse@arm.com
Signed-off-by: Will Deacon 
[florian: resolved conflicts in arch/arm64/tools/cpucaps and cpu_errata.c]
Signed-off-by: Florian Fainelli 
Signed-off-by: Greg Kroah-Hartman

iio: ABI: Fix wrong format of differential capacitance channel ABI.

2022-10-26T11:15:41+00:00

[ Upstream commit 1efc41035f1841acf0af2bab153158e27ce94f10 ]

in_ only occurs once in these attributes.

Fixes: 0baf29d658c7 ("staging:iio:documentation Add abi docs for capacitance adcs.")
Signed-off-by: Jonathan Cameron 
Reviewed-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20220626122938.582107-3-jic23@kernel.org
Signed-off-by: Sasha Levin

ARM: dts: fix Moxa SDIO 'compatible', remove 'sdhci' misnomer

2022-10-26T11:15:34+00:00

[ Upstream commit 02181e68275d28cab3c3f755852770367f1bc229 ]

Driver moxart-mmc.c has .compatible = "moxa,moxart-mmc".

But moxart .dts/.dtsi and the documentation file moxa,moxart-dma.txt
contain compatible = "moxa,moxart-sdhci".

Change moxart .dts/.dtsi files and moxa,moxart-dma.txt to match the driver.

Replace 'sdhci' with 'mmc' in names too, since SDHCI is a different
controller from FTSDC010.

Suggested-by: Arnd Bergmann 
Signed-off-by: Sergei Antonov 
Cc: Jonas Jensen 
Link: https://lore.kernel.org/r/20220907175341.1477383-1-saproj@gmail.com'
Signed-off-by: Arnd Bergmann 
Signed-off-by: Sasha Levin

x86/bugs: Add "unknown" reporting for MMIO Stale Data

2022-09-05T08:23:56+00:00

commit 7df548840c496b0141fb2404b889c346380c2b22 upstream.

Older Intel CPUs that are not in the affected processor list for MMIO
Stale Data vulnerabilities currently report "Not affected" in sysfs,
which may not be correct. Vulnerability status for these older CPUs is
unknown.

Add known-not-affected CPUs to the whitelist. Report "unknown"
mitigation status for CPUs that are not in blacklist, whitelist and also
don't enumerate MSR ARCH_CAPABILITIES bits that reflect hardware
immunity to MMIO Stale Data vulnerabilities.

Mitigation is not deployed when the status is unknown.

  [ bp: Massage, fixup. ]

Fixes: 8d50cdf8b834 ("x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data")
Suggested-by: Andrew Cooper 
Suggested-by: Tony Luck 
Signed-off-by: Pawan Gupta 
Signed-off-by: Borislav Petkov 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/a932c154772f2121794a5f2eded1a11013114711.1657846269.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

ipv4: Fix data-races around sysctl_ip_dynaddr.

2022-07-21T18:40:31+00:00

[ Upstream commit e49e4aff7ec19b2d0d0957ee30e93dade57dab9e ]

While reading sysctl_ip_dynaddr, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

cipso: Fix data-races around sysctl.

2022-07-21T18:40:31+00:00

[ Upstream commit dd44f04b9214adb68ef5684ae87a81ba03632250 ]

While reading cipso sysctl variables, they can be changed concurrently.
So, we need to add READ_ONCE() to avoid data-races.

Fixes: 446fda4f2682 ("[NetLabel]: CIPSOv4 engine")
Signed-off-by: Kuniyuki Iwashima 
Acked-by: Paul Moore 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

iio: adc: vf610: fix conversion mode sysfs node name

2022-07-02T14:17:15+00:00

[ Upstream commit f1a633b15cd5371a2a83f02c513984e51132dd68 ]

The documentation missed the "in_" prefix for this IIO_SHARED_BY_DIR
entry.

Fixes: bf04c1a367e3 ("iio: adc: vf610: implement configurable conversion modes")
Signed-off-by: Baruch Siach 
Acked-by: Haibo Chen 
Link: https://lore.kernel.org/r/560dc93fafe5ef7e9a409885fd20b6beac3973d8.1653900626.git.baruch@tkos.co.il
Signed-off-by: Jonathan Cameron 
Signed-off-by: Sasha Levin

Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""

2022-06-25T09:45:19+00:00

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 
Tested-by: Oleksandr Natalenko 
Cc: Christoph Hellwig 
Signed-off-by: Linus Torvalds 
[OP: backport to 4.14: apply swiotlb_tbl_map_single() changes in lib/swiotlb.c]
Signed-off-by: Ovidiu Panait 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

swiotlb: fix info leak with DMA_FROM_DEVICE

2022-06-25T09:45:19+00:00

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 
Signed-off-by: Christoph Hellwig 
[OP: backport to 4.14: apply swiotlb_tbl_map_single() changes in lib/swiotlb.c]
Signed-off-by: Ovidiu Panait 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

random: fix sysctl documentation nits

2022-06-25T09:45:12+00:00

commit 069c4ea6871c18bd368f27756e0f91ffb524a788 upstream.

A semicolon was missing, and the almost-alphabetical-but-not ordering
was confusing, so regroup these by category instead.

Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman