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[ Upstream commit d4eaa2837851db2bfed572898bfc17f9a9f9151e ]
For kvmalloc'ed data object that contains sensitive information like
cryptographic keys, we need to make sure that the buffer is always cleared
before freeing it. Using memset() alone for buffer clearing may not
provide certainty as the compiler may compile it away. To be sure, the
special memzero_explicit() has to be used.
This patch introduces a new kvfree_sensitive() for freeing those sensitive
data objects allocated by kvmalloc(). The relevant places where
kvfree_sensitive() can be used are modified to use it.
Fixes: 4f0882491a14 ("KEYS: Avoid false positive ENOMEM error on key read")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Link: http://lkml.kernel.org/r/20200407200318.11711-1-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 594cc251fdd0d231d342d88b2fdff4bc42fb0690 upstream.
Originally, the rule used to be that you'd have to do access_ok()
separately, and then user_access_begin() before actually doing the
direct (optimized) user access.
But experience has shown that people then decide not to do access_ok()
at all, and instead rely on it being implied by other operations or
similar. Which makes it very hard to verify that the access has
actually been range-checked.
If you use the unsafe direct user accesses, hardware features (either
SMAP - Supervisor Mode Access Protection - on x86, or PAN - Privileged
Access Never - on ARM) do force you to use user_access_begin(). But
nothing really forces the range check.
By putting the range check into user_access_begin(), we actually force
people to do the right thing (tm), and the range check vill be visible
near the actual accesses. We have way too long a history of people
trying to avoid them.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit e9d7144597b10ff13ff2264c059f7d4a7fbc89ac upstream
Intel uses the same family/model for several CPUs. Sometimes the
stepping must be checked to tell them apart.
On x86 there can be at most 16 steppings. Add a steppings bitmask to
x86_cpu_id and a X86_MATCH_VENDOR_FAMILY_MODEL_STEPPING_FEATURE macro
and support for matching against family/model/stepping.
[ bp: Massage.
tglx: Lightweight variant for backporting ]
Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 6dd912f82680761d8fb6b1bb274a69d4c7010988 ]
Syzkaller again found a path to a kernel crash through bad gso input:
a packet with gso size exceeding len.
These packets are dropped in tcp_gso_segment and udp[46]_ufo_fragment.
But they may affect gso size calculations earlier in the path.
Now that we have thlen as of commit 9274124f023b ("net: stricter
validation of untrusted gso packets"), check gso_size at entry too.
Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 83fc5dd57f86c3ec7d6d22565a6ff6c948853b64 upstream.
The definitions of MMC_IOC_CMD and of MMC_IOC_MULTI_CMD rely on
MMC_BLOCK_MAJOR:
#define MMC_IOC_CMD _IOWR(MMC_BLOCK_MAJOR, 0, struct mmc_ioc_cmd)
#define MMC_IOC_MULTI_CMD _IOWR(MMC_BLOCK_MAJOR, 1, struct mmc_ioc_multi_cmd)
However, MMC_BLOCK_MAJOR is defined in linux/major.h and
linux/mmc/ioctl.h did not include it.
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200511161902.191405-1-Jerome.Pouiller@silabs.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 4946ea5c1237036155c3b3a24f049fd5f849f8f6 upstream.
>> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
extern const char *const pptp_msg_name(u_int16_t msg);
^~~~~~
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 4c559f15efcc ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 4c559f15efcc43b996f4da528cd7f9483aaca36d upstream.
Dan Carpenter says: "Smatch complains that the value for "cmd" comes
from the network and can't be trusted."
Add pptp_msg_name() helper function that checks for the array boundary.
Fixes: f09943fefe6b ("[NETFILTER]: nf_conntrack/nf_nat: add PPTP helper port")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 29e4276667e24ee6b91d9f91064d8fda9a210ea1 upstream.
s/xfrm_state_offload/xfrm_user_offload/
Fixes: d77e38e612a ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: Antony Antony <antony@phenome.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit c85f4abe66bea0b5db8d28d55da760c4fe0a0301 upstream.
Fix use after free when user user space request uobject concurrently for
the same object, within the RCU grace period.
In that case, remove_handle_idr_uobject() is called twice and we will have
an extra put on the uobject which cause use after free. Fix it by leaving
the uobject write locked after it was removed from the idr.
Call to rdma_lookup_put_uobject with UVERBS_LOOKUP_DESTROY instead of
UVERBS_LOOKUP_WRITE will do the work.
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 1381 at lib/refcount.c:28 refcount_warn_saturate+0xfe/0x1a0
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 1381 Comm: syz-executor.0 Not tainted 5.5.0-rc3 #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x94/0xce
panic+0x234/0x56f
__warn+0x1cc/0x1e1
report_bug+0x200/0x310
fixup_bug.part.11+0x32/0x80
do_error_trap+0xd3/0x100
do_invalid_op+0x31/0x40
invalid_op+0x1e/0x30
RIP: 0010:refcount_warn_saturate+0xfe/0x1a0
Code: 0f 0b eb 9b e8 23 f6 6d ff 80 3d 6c d4 19 03 00 75 8d e8 15 f6 6d ff 48 c7 c7 c0 02 55 bd c6 05 57 d4 19 03 01 e8 a2 58 49 ff <0f> 0b e9 6e ff ff ff e8 f6 f5 6d ff 80 3d 42 d4 19 03 00 0f 85 5c
RSP: 0018:ffffc90002df7b98 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88810f6a193c RCX: ffffffffba649009
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811b0283cc
RBP: 0000000000000003 R08: ffffed10236060e3 R09: ffffed10236060e3
R10: 0000000000000001 R11: ffffed10236060e2 R12: ffff88810f6a193c
R13: ffffc90002df7d60 R14: 0000000000000000 R15: ffff888116ae6a08
uverbs_uobject_put+0xfd/0x140
__uobj_perform_destroy+0x3d/0x60
ib_uverbs_close_xrcd+0x148/0x170
ib_uverbs_write+0xaa5/0xdf0
__vfs_write+0x7c/0x100
vfs_write+0x168/0x4a0
ksys_write+0xc8/0x200
do_syscall_64+0x9c/0x390
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b49
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f759d122c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000073bfa8 RCX: 0000000000465b49
RDX: 000000000000000c RSI: 0000000020000080 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f759d1236bc
R13: 00000000004ca27c R14: 000000000070de40 R15: 00000000ffffffff
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: 0x39400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
Fixes: 7452a3c745a2 ("IB/uverbs: Allow RDMA_REMOVE_DESTROY to work concurrently with disassociate")
Link: https://lore.kernel.org/r/20200527135534.482279-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 4377748c7b5187c3342a60fa2ceb60c8a57a8488 ]
drivers/hwmon/amd_energy.c:195:15: error: invalid operands to binary expression ('void' and 'int')
(channel - data->nr_cpus));
~~~~~~~~~^~~~~~~~~~~~~~~~~
include/asm-generic/topology.h:51:42: note: expanded from macro 'cpumask_of_node'
#define cpumask_of_node(node) ((void)node, cpu_online_mask)
^~~~
include/linux/cpumask.h:618:72: note: expanded from macro 'cpumask_first_and'
#define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
^~~~~
Fixes: f0b848ce6fe9 ("cpumask: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask")
Fixes: 8abee9566b7e ("hwmon: Add amd_energy driver to report energy counters")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200527134623.930247-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6988f31d558aa8c744464a7f6d91d34ada48ad12 ]
Replace superfluous VM_BUG_ON() with comment about correct usage.
Technically reverts commit 1d148e218a0d ("mm: add VM_BUG_ON_PAGE() to
page_mapcount()"), but context lines have changed.
Function isolate_migratepages_block() runs some checks out of lru_lock
when choose pages for migration. After checking PageLRU() it checks
extra page references by comparing page_count() and page_mapcount().
Between these two checks page could be removed from lru, freed and taken
by slab.
As a result this race triggers VM_BUG_ON(PageSlab()) in page_mapcount().
Race window is tiny. For certain workload this happens around once a
year.
page:ffffea0105ca9380 count:1 mapcount:0 mapping:ffff88ff7712c180 index:0x0 compound_mapcount: 0
flags: 0x500000000008100(slab|head)
raw: 0500000000008100 dead000000000100 dead000000000200 ffff88ff7712c180
raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(PageSlab(page))
------------[ cut here ]------------
kernel BUG at ./include/linux/mm.h:628!
invalid opcode: 0000 [#1] SMP NOPTI
CPU: 77 PID: 504 Comm: kcompactd1 Tainted: G W 4.19.109-27 #1
Hardware name: Yandex T175-N41-Y3N/MY81-EX0-Y3N, BIOS R05 06/20/2019
RIP: 0010:isolate_migratepages_block+0x986/0x9b0
The code in isolate_migratepages_block() was added in commit
119d6d59dcc0 ("mm, compaction: avoid isolating pinned pages") before
adding VM_BUG_ON into page_mapcount().
This race has been predicted in 2015 by Vlastimil Babka (see link
below).
[akpm@linux-foundation.org: comment tweaks, per Hugh]
Fixes: 1d148e218a0d ("mm: add VM_BUG_ON_PAGE() to page_mapcount()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/159032779896.957378.7852761411265662220.stgit@buzz
Link: https://lore.kernel.org/lkml/557710E1.6060103@suse.cz/
Link: https://lore.kernel.org/linux-mm/158937872515.474360.5066096871639561424.stgit@buzz/T/ (v1)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b15e62631c5f19fea9895f7632dae9c1b27fe0cd ]
When a new action is installed, firstuse field of 'tcf_t' is explicitly set
to 0. Value of zero means "new action, not yet used"; as a packet hits the
action, 'firstuse' is stamped with the current jiffies value.
tcf_tm_dump() should return 0 for firstuse if action has not yet been hit.
Fixes: 48d8ee1694dd ("net sched actions: aggregate dumping of actions timeinfo")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 17d00e839d3b592da9659c1977d45f85b77f986a ]
When FW response to commands is very slow and all command entries in
use are waiting for completion we can have a race where commands can get
timeout before they get out of the queue and handled. Timeout
completion on uninitialized command will cause releasing command's
buffers before accessing it for initialization and then we will get NULL
pointer exception while trying access it. It may also cause releasing
buffers of another command since we may have timeout completion before
even allocating entry index for this command.
Add entry handling completion to avoid this race.
Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit d1f129470e6cb79b8b97fecd12689f6eb49e27fe ]
Add a tracepoint to track received ACKs that are discarded due to being
outside of the Tx window.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 1194c4133195dfcb6c5fc0935d54bbed872a5285 ]
Add the Hyper-V _DSM command set to the white list of NVDIMM command
sets.
This command set is documented at http://www.uefi.org/RFIC_LIST
(see "Virtual NVDIMM 0x1901").
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6fc4dbcf0276279d488c5fbbfabe94734134f4fa ]
The function padata_reorder will use a timer when it cannot progress
while completed jobs are outstanding (pd->reorder_objects > 0). This
is suboptimal as if we do end up using the timer then it would have
introduced a gratuitous delay of one second.
In fact we can easily distinguish between whether completed jobs
are outstanding and whether we can make progress. All we have to
do is look at the next pqueue list.
This patch does that by replacing pd->processed with pd->cpu so
that the next pqueue is more accessible.
A work queue is used instead of the original try_again to avoid
hogging the CPU.
Note that we don't bother removing the work queue in
padata_flush_queues because the whole premise is broken. You
cannot flush async crypto requests so it makes no sense to even
try. A subsequent patch will fix it by replacing it with a ref
counting scheme.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[dj: - adjust context
- corrected setup_timer -> timer_setup to delete hunk
- skip padata_flush_queues() hunk, function already removed
in 4.19]
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit a9a3ed1eff3601b63aea4fb462d8b3b92c7c1e7e upstream.
... or the odyssey of trying to disable the stack protector for the
function which generates the stack canary value.
The whole story started with Sergei reporting a boot crash with a kernel
built with gcc-10:
Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
Call Trace:
dump_stack
panic
? start_secondary
__stack_chk_fail
start_secondary
secondary_startup_64
-—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary
This happens because gcc-10 tail-call optimizes the last function call
in start_secondary() - cpu_startup_entry() - and thus emits a stack
canary check which fails because the canary value changes after the
boot_init_stack_canary() call.
To fix that, the initial attempt was to mark the one function which
generates the stack canary with:
__attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)
however, using the optimize attribute doesn't work cumulatively
as the attribute does not add to but rather replaces previously
supplied optimization options - roughly all -fxxx options.
The key one among them being -fno-omit-frame-pointer and thus leading to
not present frame pointer - frame pointer which the kernel needs.
The next attempt to prevent compilers from tail-call optimizing
the last function call cpu_startup_entry(), shy of carving out
start_secondary() into a separate compilation unit and building it with
-fno-stack-protector, was to add an empty asm("").
This current solution was short and sweet, and reportedly, is supported
by both compilers but we didn't get very far this time: future (LTO?)
optimization passes could potentially eliminate this, which leads us
to the third attempt: having an actual memory barrier there which the
compiler cannot ignore or move around etc.
That should hold for a long time, but hey we said that about the other
two solutions too so...
Reported-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Kalle Valo <kvalo@codeaurora.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d upstream.
The rawmidi core allows user to resize the runtime buffer via ioctl,
and this may lead to UAF when performed during concurrent reads or
writes: the read/write functions unlock the runtime lock temporarily
during copying form/to user-space, and that's the race window.
This patch fixes the hole by introducing a reference counter for the
runtime buffer read/write access and returns -EBUSY error when the
resize is performed concurrently against read/write.
Note that the ref count field is a simple integer instead of
refcount_t here, since the all contexts accessing the buffer is
basically protected with a spinlock, hence we need no expensive atomic
ops. Also, note that this busy check is needed only against read /
write functions, and not in receive/transmit callbacks; the race can
happen only at the spinlock hole mentioned in the above, while the
whole function is protected for receive / transmit callbacks.
Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/CAFcO6XMWpUVK_yzzCpp8_XP7+=oUpQvuBeCbMffEDkpe8jWrfg@mail.gmail.com
Link: https://lore.kernel.org/r/s5heerw3r5z.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 9d82973e032e246ff5663c9805fbb5407ae932e3 upstream.
Due to a bug-report that was compiler-dependent, I updated one of my
machines to gcc-10. That shows a lot of new warnings. Happily they
seem to be mostly the valid kind, but it's going to cause a round of
churn for getting rid of them..
This is the really low-hanging fruit of removing a couple of zero-sized
arrays in some core code. We have had a round of these patches before,
and we'll have many more coming, and there is nothing special about
these except that they were particularly trivial, and triggered more
warnings than most.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 01b2bafe57b19d9119413f138765ef57990921ce upstream.
Aside from good practice, this avoids a warning from gcc 10:
./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds]
997 | ((type *)(__mptr - offsetof(type, member))); })
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’
493 | container_of(ptr, type, member)
| ^~~~~~~~~~~~
./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’
275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list)
| ^~~~~~~~~~
./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’
281 | (dev) != global_to_pnp_dev(&pnp_global); \
| ^~~~~~~~~~~~~~~~~
arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’
189 | pnp_for_each_dev(dev) {
Because the common code doesn't cast the starting list_head to the
containing struct.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[ rjw: Whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ]
gcc-10 warns around a suspicious access to an empty struct member:
net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc':
net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds]
1522 | memset(&ct->__nfct_init_offset[0], 0,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from net/netfilter/nf_conntrack_core.c:37:
include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset'
90 | u8 __nfct_init_offset[0];
| ^~~~~~~~~~~~~~~~~~
The code is correct but a bit unusual. Rework it slightly in a way that
does not trigger the warning, using an empty struct instead of an empty
array. There are probably more elegant ways to do this, but this is the
smallest change.
Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 24adbc1676af4e134e709ddc7f34cf2adc2131e4 ]
We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100%
overhead in tcp_set_rcvlowat()
This works well when skb->len/skb->truesize ratio is bigger than 0.5
But if we receive packets with small MSS, we can end up in a situation
where not enough bytes are available in the receive queue to satisfy
RCVLOWAT setting.
As our sk_rcvbuf limit is hit, we send zero windows in ACK packets,
preventing remote peer from sending more data.
Even autotuning does not help, because it only triggers at the time
user process drains the queue. If no EPOLLIN is generated, this
can not happen.
Note poll() has a similar issue, after commit
c7004482e8dc ("tcp: Respect SO_RCVLOWAT in tcp_poll().")
Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 9274124f023b5c56dc4326637d4f787968b03607 ]
Syzkaller again found a path to a kernel crash through bad gso input:
a packet with transport header extending beyond skb_headlen(skb).
Tighten validation at kernel entry:
- Verify that the transport header lies within the linear section.
To avoid pulling linux/tcp.h, verify just sizeof tcphdr.
tcp_gso_segment will call pskb_may_pull (th->doff * 4) before use.
- Match the gso_type against the ip_proto found by the flow dissector.
Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 30b2f0be23fb40e58d0ad2caf8702c2a44cda2e1 upstream.
commit 08a5bdde3812 ("mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED")
Fixed a bug where we failed to take into account a
nullfunc frame can be either non-QoS or QoS. It turns out
there is at least one more bug in
ieee80211_sta_tx_notify(), introduced in
commit 7b6ddeaf27ec ("mac80211: use QoS NDP for AP probing"),
where we forgot to check for the QoS variant and so
assumed the QoS nullfunc frame never went out
Fix this by adding a helper ieee80211_is_any_nullfunc()
which consolidates the check for non-QoS and QoS nullfunc
frames. Replace existing compound conditionals and add a
couple more missing checks for QoS variant.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200114055940.18502-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit e537654b7039aacfe8ae629d49655c0e5692ad44 ]
Implement a resource managed strongly uncachable ioremap function.
Cc: <stable@vger.kernel.org> # v4.19+
Tested-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Tuowen Zhao <ztuowen@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 8063f761cd7c17fc1d0018728936e0c33a25388a upstream.
The qed_chain data structure was modified in
commit 1a4a69751f4d ("qed: Chain support for external PBL") to support
receiving an external pbl (due to iWARP FW requirements).
The pages pointed to by the pbl are allocated in qed_chain_alloc
and their virtual address are stored in an virtual addresses array to
enable accessing and freeing the data. The physical addresses however
weren't stored and were accessed directly from the external-pbl
during free.
Destroy-qp flow, leads to freeing the external pbl before the chain is
freed, when the chain is freed it tries accessing the already freed
external pbl, leading to a use-after-free. Therefore we need to store
the physical addresses in additional to the virtual addresses in a
new data structure.
Fixes: 1a4a69751f4d ("qed: Chain support for external PBL")
Signed-off-by: Michal Kalderon <mkalderon@marvell.com>
Signed-off-by: Yuval Bason <ybason@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 23cf1ee1f1869966b75518c59b5cbda4c6c92450 upstream.
Utilize the xpo_release_rqst transport method to ensure that each
rqstp's svc_rdma_recv_ctxt object is released even when the server
cannot return a Reply for that rqstp.
Without this fix, each RPC whose Reply cannot be sent leaks one
svc_rdma_recv_ctxt. This is a 2.5KB structure, a 4KB DMA-mapped
Receive buffer, and any pages that might be part of the Reply
message.
The leak is infrequent unless the network fabric is unreliable or
Kerberos is in use, as GSS sequence window overruns, which result
in connection loss, are more common on fast transports.
Fixes: 3a88092ee319 ("svcrdma: Preserve Receive buffer until svc_rdma_sendto")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit e28b4fc652c1830796a4d3e09565f30c20f9a2cf upstream.
I hit this while testing nfsd-5.7 with kernel memory debugging
enabled on my server:
Mar 30 13:21:45 klimt kernel: BUG: unable to handle page fault for address: ffff8887e6c279a8
Mar 30 13:21:45 klimt kernel: #PF: supervisor read access in kernel mode
Mar 30 13:21:45 klimt kernel: #PF: error_code(0x0000) - not-present page
Mar 30 13:21:45 klimt kernel: PGD 3601067 P4D 3601067 PUD 87c519067 PMD 87c3e2067 PTE 800ffff8193d8060
Mar 30 13:21:45 klimt kernel: Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
Mar 30 13:21:45 klimt kernel: CPU: 2 PID: 1933 Comm: nfsd Not tainted 5.6.0-rc6-00040-g881e87a3c6f9 #1591
Mar 30 13:21:45 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015
Mar 30 13:21:45 klimt kernel: RIP: 0010:svc_rdma_post_chunk_ctxt+0xab/0x284 [rpcrdma]
Mar 30 13:21:45 klimt kernel: Code: c1 83 34 02 00 00 29 d0 85 c0 7e 72 48 8b bb a0 02 00 00 48 8d 54 24 08 4c 89 e6 48 8b 07 48 8b 40 20 e8 5a 5c 2b e1 41 89 c6 <8b> 45 20 89 44 24 04 8b 05 02 e9 01 00 85 c0 7e 33 e9 5e 01 00 00
Mar 30 13:21:45 klimt kernel: RSP: 0018:ffffc90000dfbdd8 EFLAGS: 00010286
Mar 30 13:21:45 klimt kernel: RAX: 0000000000000000 RBX: ffff8887db8db400 RCX: 0000000000000030
Mar 30 13:21:45 klimt kernel: RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000246
Mar 30 13:21:45 klimt kernel: RBP: ffff8887e6c27988 R08: 0000000000000000 R09: 0000000000000004
Mar 30 13:21:45 klimt kernel: R10: ffffc90000dfbdd8 R11: 00c068ef00000000 R12: ffff8887eb4e4a80
Mar 30 13:21:45 klimt kernel: R13: ffff8887db8db634 R14: 0000000000000000 R15: ffff8887fc931000
Mar 30 13:21:45 klimt kernel: FS: 0000000000000000(0000) GS:ffff88885bd00000(0000) knlGS:0000000000000000
Mar 30 13:21:45 klimt kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8 CR3: 000000081b72e002 CR4: 00000000001606e0
Mar 30 13:21:45 klimt kernel: Call Trace:
Mar 30 13:21:45 klimt kernel: ? svc_rdma_vec_to_sg+0x7f/0x7f [rpcrdma]
Mar 30 13:21:45 klimt kernel: svc_rdma_send_write_chunk+0x59/0xce [rpcrdma]
Mar 30 13:21:45 klimt kernel: svc_rdma_sendto+0xf9/0x3ae [rpcrdma]
Mar 30 13:21:45 klimt kernel: ? nfsd_destroy+0x51/0x51 [nfsd]
Mar 30 13:21:45 klimt kernel: svc_send+0x105/0x1e3 [sunrpc]
Mar 30 13:21:45 klimt kernel: nfsd+0xf2/0x149 [nfsd]
Mar 30 13:21:45 klimt kernel: kthread+0xf6/0xfb
Mar 30 13:21:45 klimt kernel: ? kthread_queue_delayed_work+0x74/0x74
Mar 30 13:21:45 klimt kernel: ret_from_fork+0x3a/0x50
Mar 30 13:21:45 klimt kernel: Modules linked in: ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue ib_umad ib_ipoib mlx4_ib sb_edac x86_pkg_temp_thermal iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel glue_helper crypto_simd cryptd pcspkr rpcrdma i2c_i801 rdma_ucm lpc_ich mfd_core ib_iser rdma_cm iw_cm ib_cm mei_me raid0 libiscsi mei sg scsi_transport_iscsi ioatdma wmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter nfsd nfs_acl lockd auth_rpcgss grace sunrpc ip_tables xfs libcrc32c mlx4_en sd_mod sr_mod cdrom mlx4_core crc32c_intel igb nvme i2c_algo_bit ahci i2c_core libahci nvme_core dca libata t10_pi qedr dm_mirror dm_region_hash dm_log dm_mod dax qede qed crc8 ib_uverbs ib_core
Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8
Mar 30 13:21:45 klimt kernel: ---[ end trace 87971d2ad3429424 ]---
It's absolutely not safe to use resources pointed to by the @send_wr
argument of ib_post_send() _after_ that function returns. Those
resources are typically freed by the Send completion handler, which
can run before ib_post_send() returns.
Thus the trace points currently around ib_post_send() in the
server's RPC/RDMA transport are a hazard, even when they are
disabled. Rearrange them so that they touch the Work Request only
_before_ ib_post_send() is invoked.
Fixes: bd2abef33394 ("svcrdma: Trace key RDMA API events")
Fixes: 4201c7464753 ("svcrdma: Introduce svc_rdma_send_ctxt")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 467d12f5c7842896d2de3ced74e4147ee29e97c8 upstream.
QEMU has a funny new build error message when I use the upstream kernel
headers:
CC block/file-posix.o
In file included from /home/cborntra/REPOS/qemu/include/qemu/timer.h:4,
from /home/cborntra/REPOS/qemu/include/qemu/timed-average.h:29,
from /home/cborntra/REPOS/qemu/include/block/accounting.h:28,
from /home/cborntra/REPOS/qemu/include/block/block_int.h:27,
from /home/cborntra/REPOS/qemu/block/file-posix.c:30:
/usr/include/linux/swab.h: In function `__swab':
/home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:34: error: "sizeof" is not defined, evaluates to 0 [-Werror=undef]
20 | #define BITS_PER_LONG (sizeof (unsigned long) * BITS_PER_BYTE)
| ^~~~~~
/home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:41: error: missing binary operator before token "("
20 | #define BITS_PER_LONG (sizeof (unsigned long) * BITS_PER_BYTE)
| ^
cc1: all warnings being treated as errors
make: *** [/home/cborntra/REPOS/qemu/rules.mak:69: block/file-posix.o] Error 1
rm tests/qemu-iotests/socket_scm_helper.o
This was triggered by commit d5767057c9a ("uapi: rename ext2_swab() to
swab() and share globally in swab.h"). That patch is doing
#include <asm/bitsperlong.h>
but it uses BITS_PER_LONG.
The kernel file asm/bitsperlong.h provide only __BITS_PER_LONG.
Let us use the __ variant in swap.h
Link: http://lkml.kernel.org/r/20200213142147.17604-1-borntraeger@de.ibm.com
Fixes: d5767057c9a ("uapi: rename ext2_swab() to swab() and share globally in swab.h")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit b6467ab142b708dd076f6186ca274f14af379c72 upstream.
Check that the resolved slot (somewhat confusingly named 'start') is a
valid/allocated slot before doing the final comparison to see if the
specified gfn resides in the associated slot. The resolved slot can be
invalid if the binary search loop terminated because the search index
was incremented beyond the number of used slots.
This bug has existed since the binary search algorithm was introduced,
but went unnoticed because KVM statically allocated memory for the max
number of slots, i.e. the access would only be truly out-of-bounds if
all possible slots were allocated and the specified gfn was less than
the base of the lowest memslot. Commit 36947254e5f98 ("KVM: Dynamically
size memslot array based on number of used slots") eliminated the "all
possible slots allocated" condition and made the bug embarrasingly easy
to hit.
Fixes: 9c1a5d38780e6 ("kvm: optimize GFN to memslot lookup with large slots amount")
Reported-by: syzbot+d889b59b2bb87d4047a2@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200408064059.8957-2-sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit bdebd6a2831b6fab69eb85cee74a8ba77f1a1cc2 upstream.
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:
- not detecting pgoff<<PAGE_SHIFT overflow
- not detecting (pgoff<<PAGE_SHIFT)+usize overflow
- not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
vmalloc allocation
- comparing a potentially wildly out-of-bounds pointer with the end of
the vmalloc region
In particular, since commit fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.
This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.
To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().
In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.
Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit a07479147be03d2450376ebaff9ea1a0682f25d6 upstream.
This change removes the semi-colon from the devm_iio_device_register()
macro which seems to have been added by accident.
Fixes: 63b19547cc3d9 ("iio: Use macro magic to avoid manual assign of driver_module")
Signed-off-by: Lars Engebretsen <lars@engebretsen.ch>
Cc: <Stable@vger.kernel.org>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 9bacd256f1354883d3c1402655153367982bba49 ]
TCP stack is dumb in how it cooks its output packets.
Depending on MAX_HEADER value, we might chose a bad ending point
for the headers.
If we align the end of TCP headers to cache line boundary, we
make sure to always use the smallest number of cache lines,
which always help.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 917248144db5d7320655dbb41d3af0b8a0f3d589 upstream.
__kvm_map_gfn()'s call to gfn_to_pfn_memslot() is
* relatively expensive
* in certain cases (such as when done from atomic context) cannot be called
Stashing gfn-to-pfn mapping should help with both cases.
This is part of CVE-2019-3016.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 1eff70a9abd46f175defafd29bc17ad456f398a7 upstream.
kvm_vcpu_(un)map operates on gfns from any current address space.
In certain cases we want to make sure we are not mapping SMRAM
and for that we can use kvm_(un)map_gfn() that we are introducing
in this patch.
This is part of CVE-2019-3016.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit e45adf665a53df0db37f784ed87c6b57ddd81885 upstream.
In KVM, specially for nested guests, there is a dominant pattern of:
=> map guest memory -> do_something -> unmap guest memory
In addition to all this unnecessarily noise in the code due to boiler plate
code, most of the time the mapping function does not properly handle memory
that is not backed by "struct page". This new guest mapping API encapsulate
most of this boiler plate code and also handles guest memory that is not
backed by "struct page".
The current implementation of this API is using memremap for memory that is
not backed by a "struct page" which would lead to a huge slow-down if it
was used for high-frequency mapping operations. The API does not have any
effect on current setups where guest memory is backed by a "struct page".
Further patches are going to also introduce a pfn-cache which would
significantly improve the performance of the memremap case.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 4.19 as dependency of commit 1eff70a9abd4
"x86/kvm: Introduce kvm_(un)map_gfn()"]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit c780e86dd48ef6467a1146cf7d0fe1e05a635039 upstream.
KASAN is reporting that __blk_add_trace() has a use-after-free issue
when accessing q->blk_trace. Indeed the switching of block tracing (and
thus eventual freeing of q->blk_trace) is completely unsynchronized with
the currently running tracing and thus it can happen that the blk_trace
structure is being freed just while __blk_add_trace() works on it.
Protect accesses to q->blk_trace by RCU during tracing and make sure we
wait for the end of RCU grace period when shutting down tracing. Luckily
that is rare enough event that we can afford that. Note that postponing
the freeing of blk_trace to an RCU callback should better be avoided as
it could have unexpected user visible side-effects as debugfs files
would be still existing for a short while block tracing has been shut
down.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=205711
CC: stable@vger.kernel.org
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Tristan |
