linux-stable.git, branch v5.2.17 Linux kernel stable tree Linux 5.2.17 2019-09-21T05:18:51+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2019-09-21T05:18:51+00:00 5e408889e4af03a27b77cf4635934fefb9f4afab 






vfs: Fix refcounting of filenames in fs_parser
2019-09-21T05:18:51+00:00

David Howells
dhowells@redhat.com

2019-03-25T16:38:22+00:00

12434939ba58717e0259ffe7375f9aa7a5f1c0b8

commit 7cdfa44227b0d8842d46a775cebe4311150cb8f2 upstream.

Fix an overput in which filename_lookup() unconditionally drops a ref to
the filename it was given, but this isn't taken account of in the caller,
fs_lookup_param().

Addresses-Coverity-ID: 1443811 ("Use after free")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit 7cdfa44227b0d8842d46a775cebe4311150cb8f2 upstream.

Fix an overput in which filename_lookup() unconditionally drops a ref to
the filename it was given, but this isn't taken account of in the caller,
fs_lookup_param().

Addresses-Coverity-ID: 1443811 ("Use after free")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








media: technisat-usb2: break out of loop at end of buffer
2019-09-21T05:18:50+00:00

Sean Young
sean@mess.org

2019-07-03T14:52:39+00:00

d4911cc1f4b663f5a19707610aa7623d9f94c78a

commit 0c4df39e504bf925ab666132ac3c98d6cbbe380b upstream.

Ensure we do not access the buffer beyond the end if no 0xff byte
is encountered.

Reported-by: syzbot+eaaaf38a95427be88f4b@syzkaller.appspotmail.com
Signed-off-by: Sean Young <sean@mess.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit 0c4df39e504bf925ab666132ac3c98d6cbbe380b upstream.

Ensure we do not access the buffer beyond the end if no 0xff byte
is encountered.

Reported-by: syzbot+eaaaf38a95427be88f4b@syzkaller.appspotmail.com
Signed-off-by: Sean Young <sean@mess.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








floppy: fix usercopy direction
2019-09-21T05:18:50+00:00

Jann Horn
jannh@google.com

2019-03-26T22:03:48+00:00

19ad4c4fe19c57acc3add672c5ece6563b26ad43

commit 52f6f9d74f31078964ca1574f7bb612da7877ac8 upstream.

As sparse points out, these two copy_from_user() should actually be
copy_to_user().

Fixes: 229b53c9bf4e ("take floppy compat ioctls to sodding floppy.c")
Cc: stable@vger.kernel.org
Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit 52f6f9d74f31078964ca1574f7bb612da7877ac8 upstream.

As sparse points out, these two copy_from_user() should actually be
copy_to_user().

Fixes: 229b53c9bf4e ("take floppy compat ioctls to sodding floppy.c")
Cc: stable@vger.kernel.org
Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








ovl: fix regression caused by overlapping layers detection
2019-09-21T05:18:50+00:00

Amir Goldstein
amir73il@gmail.com

2019-07-12T12:24:34+00:00

d7aa8c546ab97b9011f805042b3647693fce107f

commit 0be0bfd2de9dfdd2098a9c5b14bdd8f739c9165d upstream.

Once upon a time, commit 2cac0c00a6cd ("ovl: get exclusive ownership on
upper/work dirs") in v4.13 added some sanity checks on overlayfs layers.
This change caused a docker regression. The root cause was mount leaks
by docker, which as far as I know, still exist.

To mitigate the regression, commit 85fdee1eef1a ("ovl: fix regression
caused by exclusive upper/work dir protection") in v4.14 turned the
mount errors into warnings for the default index=off configuration.

Recently, commit 146d62e5a586 ("ovl: detect overlapping layers") in
v5.2, re-introduced exclusive upper/work dir checks regardless of
index=off configuration.

This changes the status quo and mount leak related bug reports have
started to re-surface. Restore the status quo to fix the regressions.
To clarify, index=off does NOT relax overlapping layers check for this
ovelayfs mount. index=off only relaxes exclusive upper/work dir checks
with another overlayfs mount.

To cover the part of overlapping layers detection that used the
exclusive upper/work dir checks to detect overlap with self upper/work
dir, add a trap also on the work base dir.

Link: https://github.com/moby/moby/issues/34672
Link: https://lore.kernel.org/linux-fsdevel/20171006121405.GA32700@veci.piliscsaba.szeredi.hu/
Link: https://github.com/containers/libpod/issues/3540
Fixes: 146d62e5a586 ("ovl: detect overlapping layers")
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Tested-by: Colin Walters <walters@verbum.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit 0be0bfd2de9dfdd2098a9c5b14bdd8f739c9165d upstream.

Once upon a time, commit 2cac0c00a6cd ("ovl: get exclusive ownership on
upper/work dirs") in v4.13 added some sanity checks on overlayfs layers.
This change caused a docker regression. The root cause was mount leaks
by docker, which as far as I know, still exist.

To mitigate the regression, commit 85fdee1eef1a ("ovl: fix regression
caused by exclusive upper/work dir protection") in v4.14 turned the
mount errors into warnings for the default index=off configuration.

Recently, commit 146d62e5a586 ("ovl: detect overlapping layers") in
v5.2, re-introduced exclusive upper/work dir checks regardless of
index=off configuration.

This changes the status quo and mount leak related bug reports have
started to re-surface. Restore the status quo to fix the regressions.
To clarify, index=off does NOT relax overlapping layers check for this
ovelayfs mount. index=off only relaxes exclusive upper/work dir checks
with another overlayfs mount.

To cover the part of overlapping layers detection that used the
exclusive upper/work dir checks to detect overlap with self upper/work
dir, add a trap also on the work base dir.

Link: https://github.com/moby/moby/issues/34672
Link: https://lore.kernel.org/linux-fsdevel/20171006121405.GA32700@veci.piliscsaba.szeredi.hu/
Link: https://github.com/containers/libpod/issues/3540
Fixes: 146d62e5a586 ("ovl: detect overlapping layers")
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Tested-by: Colin Walters <walters@verbum.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








Revert "arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}"
2019-09-21T05:18:50+00:00

Will Deacon
will@kernel.org

2019-08-22T13:58:37+00:00

52f2aba47d7143cbddac33929e605a7d3022631b

commit d0b7a302d58abe24ed0f32a0672dd4c356bb73db upstream.

This reverts commit 24fe1b0efad4fcdd32ce46cffeab297f22581707.

Commit 24fe1b0efad4fcdd ("arm64: Remove unnecessary ISBs from
set_{pte,pmd,pud}") removed ISB instructions immediately following updates
to the page table, on the grounds that they are not required by the
architecture and a DSB alone is sufficient to ensure that subsequent data
accesses use the new translation:

  DDI0487E_a, B2-128:

  | ... no instruction that appears in program order after the DSB
  | instruction can alter any state of the system or perform any part of
  | its functionality until the DSB completes other than:
  |
  | * Being fetched from memory and decoded
  | * Reading the general-purpose, SIMD and floating-point,
  |   Special-purpose, or System registers that are directly or indirectly
  |   read without causing side-effects.

However, the same document also states the following:

  DDI0487E_a, B2-125:

  | DMB and DSB instructions affect reads and writes to the memory system
  | generated by Load/Store instructions and data or unified cache
  | maintenance instructions being executed by the PE. Instruction fetches
  | or accesses caused by a hardware translation table access are not
  | explicit accesses.

which appears to claim that the DSB alone is insufficient.  Unfortunately,
some CPU designers have followed the second clause above, whereas in Linux
we've been relying on the first. This means that our mapping sequence:

	MOV	X0, <valid pte>
	STR	X0, [Xptep]	// Store new PTE to page table
	DSB	ISHST
	LDR	X1, [X2]	// Translates using the new PTE

can actually raise a translation fault on the load instruction because the
translation can be performed speculatively before the page table update and
then marked as "faulting" by the CPU. For user PTEs, this is ok because we
can handle the spurious fault, but for kernel PTEs and intermediate table
entries this results in a panic().

Revert the offending commit to reintroduce the missing barriers.

Cc: <stable@vger.kernel.org>
Fixes: 24fe1b0efad4fcdd ("arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}")
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit d0b7a302d58abe24ed0f32a0672dd4c356bb73db upstream.

This reverts commit 24fe1b0efad4fcdd32ce46cffeab297f22581707.

Commit 24fe1b0efad4fcdd ("arm64: Remove unnecessary ISBs from
set_{pte,pmd,pud}") removed ISB instructions immediately following updates
to the page table, on the grounds that they are not required by the
architecture and a DSB alone is sufficient to ensure that subsequent data
accesses use the new translation:

  DDI0487E_a, B2-128:

  | ... no instruction that appears in program order after the DSB
  | instruction can alter any state of the system or perform any part of
  | its functionality until the DSB completes other than:
  |
  | * Being fetched from memory and decoded
  | * Reading the general-purpose, SIMD and floating-point,
  |   Special-purpose, or System registers that are directly or indirectly
  |   read without causing side-effects.

However, the same document also states the following:

  DDI0487E_a, B2-125:

  | DMB and DSB instructions affect reads and writes to the memory system
  | generated by Load/Store instructions and data or unified cache
  | maintenance instructions being executed by the PE. Instruction fetches
  | or accesses caused by a hardware translation table access are not
  | explicit accesses.

which appears to claim that the DSB alone is insufficient.  Unfortunately,
some CPU designers have followed the second clause above, whereas in Linux
we've been relying on the first. This means that our mapping sequence:

	MOV	X0, <valid pte>
	STR	X0, [Xptep]	// Store new PTE to page table
	DSB	ISHST
	LDR	X1, [X2]	// Translates using the new PTE

can actually raise a translation fault on the load instruction because the
translation can be performed speculatively before the page table update and
then marked as "faulting" by the CPU. For user PTEs, this is ok because we
can handle the spurious fault, but for kernel PTEs and intermediate table
entries this results in a panic().

Revert the offending commit to reintroduce the missing barriers.

Cc: <stable@vger.kernel.org>
Fixes: 24fe1b0efad4fcdd ("arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}")
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








iommu/amd: Fix race in increase_address_space()
2019-09-21T05:18:50+00:00

Joerg Roedel
jroedel@suse.de

2019-09-06T08:39:54+00:00

785ca708a908b9c596ede852470ba28b8dc3e40b

[ Upstream commit 754265bcab78a9014f0f99cd35e0d610fcd7dfa7 ]

After the conversion to lock-less dma-api call the
increase_address_space() function can be called without any
locking. Multiple CPUs could potentially race for increasing
the address space, leading to invalid domain->mode settings
and invalid page-tables. This has been happening in the wild
under high IO load and memory pressure.

Fix the race by locking this operation. The function is
called infrequently so that this does not introduce
a performance regression in the dma-api path again.

Reported-by: Qian Cai <cai@lca.pw>
Fixes: 256e4621c21a ('iommu/amd: Make use of the generic IOVA allocator')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 754265bcab78a9014f0f99cd35e0d610fcd7dfa7 ]

After the conversion to lock-less dma-api call the
increase_address_space() function can be called without any
locking. Multiple CPUs could potentially race for increasing
the address space, leading to invalid domain->mode settings
and invalid page-tables. This has been happening in the wild
under high IO load and memory pressure.

Fix the race by locking this operation. The function is
called infrequently so that this does not introduce
a performance regression in the dma-api path again.

Reported-by: Qian Cai <cai@lca.pw>
Fixes: 256e4621c21a ('iommu/amd: Make use of the generic IOVA allocator')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>







iommu/amd: Flush old domains in kdump kernel
2019-09-21T05:18:49+00:00

Stuart Hayes
stuart.w.hayes@gmail.com

2019-09-05T17:09:48+00:00

ed52f6cf0e84ab34b2f1fa4bc865be941ec606cd

[ Upstream commit 36b7200f67dfe75b416b5281ed4ace9927b513bc ]

When devices are attached to the amd_iommu in a kdump kernel, the old device
table entries (DTEs), which were copied from the crashed kernel, will be
overwritten with a new domain number.  When the new DTE is written, the IOMMU
is told to flush the DTE from its internal cache--but it is not told to flush
the translation cache entries for the old domain number.

Without this patch, AMD systems using the tg3 network driver fail when kdump
tries to save the vmcore to a network system, showing network timeouts and
(sometimes) IOMMU errors in the kernel log.

This patch will flush IOMMU translation cache entries for the old domain when
a DTE gets overwritten with a new domain number.

Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Fixes: 3ac3e5ee5ed5 ('iommu/amd: Copy old trans table from old kernel')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 36b7200f67dfe75b416b5281ed4ace9927b513bc ]

When devices are attached to the amd_iommu in a kdump kernel, the old device
table entries (DTEs), which were copied from the crashed kernel, will be
overwritten with a new domain number.  When the new DTE is written, the IOMMU
is told to flush the DTE from its internal cache--but it is not told to flush
the translation cache entries for the old domain number.

Without this patch, AMD systems using the tg3 network driver fail when kdump
tries to save the vmcore to a network system, showing network timeouts and
(sometimes) IOMMU errors in the kernel log.

This patch will flush IOMMU translation cache entries for the old domain when
a DTE gets overwritten with a new domain number.

Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Fixes: 3ac3e5ee5ed5 ('iommu/amd: Copy old trans table from old kernel')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>







keys: Fix missing null pointer check in request_key_auth_describe()
2019-09-21T05:18:49+00:00

Hillf Danton
hdanton@sina.com

2019-09-02T12:37:29+00:00

24962eb0edd0b75ed5b053627d37c9e9337e08c6

[ Upstream commit d41a3effbb53b1bcea41e328d16a4d046a508381 ]

If a request_key authentication token key gets revoked, there's a window in
which request_key_auth_describe() can see it with a NULL payload - but it
makes no check for this and something like the following oops may occur:

	BUG: Kernel NULL pointer dereference at 0x00000038
	Faulting instruction address: 0xc0000000004ddf30
	Oops: Kernel access of bad area, sig: 11 [#1]
	...
	NIP [...] request_key_auth_describe+0x90/0xd0
	LR [...] request_key_auth_describe+0x54/0xd0
	Call Trace:
	[...] request_key_auth_describe+0x54/0xd0 (unreliable)
	[...] proc_keys_show+0x308/0x4c0
	[...] seq_read+0x3d0/0x540
	[...] proc_reg_read+0x90/0x110
	[...] __vfs_read+0x3c/0x70
	[...] vfs_read+0xb4/0x1b0
	[...] ksys_read+0x7c/0x130
	[...] system_call+0x5c/0x70

Fix this by checking for a NULL pointer when describing such a key.

Also make the read routine check for a NULL pointer to be on the safe side.

[DH: Modified to not take already-held rcu lock and modified to also check
 in the read routine]

Fixes: 04c567d9313e ("[PATCH] Keys: Fix race between two instantiators of a key")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit d41a3effbb53b1bcea41e328d16a4d046a508381 ]

If a request_key authentication token key gets revoked, there's a window in
which request_key_auth_describe() can see it with a NULL payload - but it
makes no check for this and something like the following oops may occur:

	BUG: Kernel NULL pointer dereference at 0x00000038
	Faulting instruction address: 0xc0000000004ddf30
	Oops: Kernel access of bad area, sig: 11 [#1]
	...
	NIP [...] request_key_auth_describe+0x90/0xd0
	LR [...] request_key_auth_describe+0x54/0xd0
	Call Trace:
	[...] request_key_auth_describe+0x54/0xd0 (unreliable)
	[...] proc_keys_show+0x308/0x4c0
	[...] seq_read+0x3d0/0x540
	[...] proc_reg_read+0x90/0x110
	[...] __vfs_read+0x3c/0x70
	[...] vfs_read+0xb4/0x1b0
	[...] ksys_read+0x7c/0x130
	[...] system_call+0x5c/0x70

Fix this by checking for a NULL pointer when describing such a key.

Also make the read routine check for a NULL pointer to be on the safe side.

[DH: Modified to not take already-held rcu lock and modified to also check
 in the read routine]

Fixes: 04c567d9313e ("[PATCH] Keys: Fix race between two instantiators of a key")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>







dmaengine: rcar-dmac: Fix DMACHCLR handling if iommu is mapped
2019-09-21T05:18:49+00:00

Yoshihiro Shimoda
yoshihiro.shimoda.uh@renesas.com

2019-09-02T11:44:03+00:00

16ed4b9b7bf79120ffdbef81eb0f598068d373cf

[ Upstream commit cf24aac38698bfa1d021afd3883df3c4c65143a4 ]

The commit 20c169aceb45 ("dmaengine: rcar-dmac: clear pertinence
number of channels") forgets to clear the last channel by
DMACHCLR in rcar_dmac_init() (and doesn't need to clear the first
channel) if iommu is mapped to the device. So, this patch fixes it
by using "channels_mask" bitfield.

Note that the hardware and driver don't support more than 32 bits
in DMACHCLR register anyway, so this patch should reject more than
32 channels in rcar_dmac_parse_of().

Fixes: 20c169aceb459575 ("dmaengine: rcar-dmac: clear pertinence number of channels")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1567424643-26629-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit cf24aac38698bfa1d021afd3883df3c4c65143a4 ]

The commit 20c169aceb45 ("dmaengine: rcar-dmac: clear pertinence
number of channels") forgets to clear the last channel by
DMACHCLR in rcar_dmac_init() (and doesn't need to clear the first
channel) if iommu is mapped to the device. So, this patch fixes it
by using "channels_mask" bitfield.

Note that the hardware and driver don't support more than 32 bits
in DMACHCLR register anyway, so this patch should reject more than
32 channels in rcar_dmac_parse_of().

Fixes: 20c169aceb459575 ("dmaengine: rcar-dmac: clear pertinence number of channels")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1567424643-26629-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>