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It is best to avoid any extra overhead associated with bio completion.
DM core will indirectly call a DM target's .end_io if it is defined.
In the case of DM linear, there is no need to do so (for every bio that
completes) if CONFIG_DM_ZONED is not enabled.
Avoiding an extra indirect call for every bio completion is very
important for ensuring DM linear doesn't incur more overhead that
further widens the performance gap between dm-linear and raw block
devices.
Fixes: 0be12c1c7fce7 ("dm linear: add support for zoned block devices")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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On systems with OF_IMAP_OLDWORLD_MAC set in of_irq_workarounds, the
devicetree interrupt parsing code is different, causing unit tests of
devicetree interrupt nodes to fail. Due to a bug in unittest code, which
tries to dereference an uninitialized pointer, this results in a crash.
OF: /testcase-data/phandle-tests/consumer-a: arguments longer than property
Unable to handle kernel paging request for data at address 0x00bc616e
Faulting instruction address: 0xc08e9468
Oops: Kernel access of bad area, sig: 11 [#1]
BE PREEMPT PowerMac
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.72-rc1-yocto-standard+ #1
task: cf8e0000 task.stack: cf8da000
NIP: c08e9468 LR: c08ea5bc CTR: c08ea5ac
REGS: cf8dbb50 TRAP: 0300 Not tainted (4.14.72-rc1-yocto-standard+)
MSR: 00001032 <ME,IR,DR,RI> CR: 82004044 XER: 00000000
DAR: 00bc616e DSISR: 40000000
GPR00: c08ea5bc cf8dbc00 cf8e0000 c13ca517 c13ca517 c13ca8a0 00000066 00000002
GPR08: 00000063 00bc614e c0b05865 000affff 82004048 00000000 c00047f0 00000000
GPR16: c0a80000 c0a9cc34 c13ca517 c0ad1134 05ffffff 000affff c0b05860 c0abeef8
GPR24: cecec278 cecec278 c0a8c4d0 c0a885e0 c13ca8a0 05ffffff c13ca8a0 c13ca517
NIP [c08e9468] device_node_gen_full_name+0x30/0x15c
LR [c08ea5bc] device_node_string+0x190/0x3c8
Call Trace:
[cf8dbc00] [c007f670] trace_hardirqs_on_caller+0x118/0x1fc (unreliable)
[cf8dbc40] [c08ea5bc] device_node_string+0x190/0x3c8
[cf8dbcb0] [c08eb794] pointer+0x25c/0x4d0
[cf8dbd00] [c08ebcbc] vsnprintf+0x2b4/0x5ec
[cf8dbd60] [c08ec00c] vscnprintf+0x18/0x48
[cf8dbd70] [c008e268] vprintk_store+0x4c/0x22c
[cf8dbda0] [c008ecac] vprintk_emit+0x94/0x130
[cf8dbdd0] [c008ff54] printk+0x5c/0x6c
[cf8dbe10] [c0b8ddd4] of_unittest+0x2220/0x26f8
[cf8dbea0] [c0004434] do_one_initcall+0x4c/0x184
[cf8dbf00] [c0b4534c] kernel_init_freeable+0x13c/0x1d8
[cf8dbf30] [c0004814] kernel_init+0x24/0x118
[cf8dbf40] [c0013398] ret_from_kernel_thread+0x5c/0x64
The problem was observed when running a qemu test for the g3beige machine
with devicetree unittests enabled.
Disable interrupt node tests on affected systems to avoid both false
unittest failures and the crash.
With this patch in place, unittest on the affected system passes with
the following message.
dt-test ### end of unittest - 144 passed, 0 failed
Fixes: 53a42093d96ef ("of: Add device tree selftests")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
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Commit 57e94c8b974db2d83c60e1139c89a70806abbea0 caused cros-ec keyboard events
be truncated on many chromebooks so that Left and Right keys on Column 12 were
always 0. Use ret as memcpy len to fix this.
The old code was using ec_dev->event_size, which is the event payload/data size
excluding event_type header, for the length of the memcpy operation. Use ret
as memcpy length to avoid the off by one and copy the whole msg->data.
Fixes: 57e94c8b974d ("mfd: cros-ec: Increase maximum mkbp event size")
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Tested-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Emil Karlson <jekarlson@gmail.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
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If dm-linear or dm-flakey are layered on top of a partition of a zoned
block device, remapping of the start sector and write pointer position
of the zones reported by a report zones BIO must be modified to account
for the target table entry mapping (start offset within the device and
entry mapping with the dm device). If the target's backing device is a
partition of a whole disk, the start sector on the physical device of
the partition must also be accounted for when modifying the zone
information. However, dm_remap_zone_report() was not considering this
last case, resulting in incorrect zone information remapping with
targets using disk partitions.
Fix this by calculating the target backing device start sector using
the position of the completed report zones BIO and the unchanged
position and size of the original report zone BIO. With this value
calculated, the start sector and write pointer position of the target
zones can be correctly remapped.
Fixes: 10999307c14e ("dm: introduce dm_remap_zone_report()")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Commit 7e6358d244e47 ("dm: fix various targets to dm_register_target
after module __init resources created") inadvertently introduced this
bug when it moved dm_register_target() after the call to KMEM_CACHE().
Fixes: 7e6358d244e47 ("dm: fix various targets to dm_register_target after module __init resources created")
Cc: stable@vger.kernel.org
Signed-off-by: Shenghui Wang <shhuiw@foxmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Commit 64bc06bb32ee broke buffered writes to journaled files (chattr
+j): we'll try to journal the buffer heads of the page being written to
in gfs2_iomap_journaled_page_done. However, the iomap code no longer
creates buffer heads, so we'll BUG() in gfs2_page_add_databufs. Fix
that by creating buffer heads ourself when needed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
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Arnd Bergmann reported that turning on -Wvla found a new (unintended) VLA usage:
arch/x86/mm/pgtable.c: In function 'pgd_alloc':
include/linux/build_bug.h:29:45: error: ISO C90 forbids variable length array 'u_pmds' [-Werror=vla]
arch/x86/mm/pgtable.c:190:34: note: in expansion of macro 'static_cpu_has'
#define PREALLOCATED_USER_PMDS (static_cpu_has(X86_FEATURE_PTI) ? \
^~~~~~~~~~~~~~
arch/x86/mm/pgtable.c:431:16: note: in expansion of macro 'PREALLOCATED_USER_PMDS'
pmd_t *u_pmds[PREALLOCATED_USER_PMDS];
^~~~~~~~~~~~~~~~~~~~~~
Use the actual size of the array that is used for X86_FEATURE_PTI,
which is known at build time, instead of the variable size.
[ mingo: Squashed original fix with followup fix to avoid bisection breakage, wrote new changelog. ]
Reported-by: Arnd Bergmann <arnd@arndb.de>
Original-written-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Fixes: 1be3f247c288 ("x86/mm: Avoid VLA in pgd_alloc()")
Link: http://lkml.kernel.org/r/20181008235434.GA35035@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Remove the leftover pglist_data::numabalancing_migrate_lock and its
initialization, we stopped using this lock with:
efaffc5e40ae ("mm, sched/numa: Remove rate-limiting of automatic NUMA balancing migration")
[ mingo: Rewrote the changelog. ]
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux-MM <linux-mm@kvack.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1538824999-31230-1-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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While the DOC at the beginning of lib/bitmap.c explicitly states that
"The number of valid bits in a given bitmap does _not_ need to be an
exact multiple of BITS_PER_LONG.", some of the bitmap operations do
indeed access BITS_PER_LONG portions of the provided bitmap no matter
the size of the provided bitmap. For example, if bitmap_intersects()
is provided with an 8 bit bitmap the operation will access
BITS_PER_LONG bits from the provided bitmap. While the operation
ensures that these extra bits do not affect the result, the memory
is still accessed.
The capacity bitmasks (CBMs) are typically stored in u32 since they
can never exceed 32 bits. A few instances exist where a bitmap_*
operation is performed on a CBM by simply pointing the bitmap operation
to the stored u32 value.
The consequence of this pattern is that some bitmap_* operations will
access out-of-bounds memory when interacting with the provided CBM. This
is confirmed with a KASAN test that reports:
BUG: KASAN: stack-out-of-bounds in __bitmap_intersects+0xa2/0x100
and
BUG: KASAN: stack-out-of-bounds in __bitmap_weight+0x58/0x90
Fix this by moving any CBM provided to a bitmap operation needing
BITS_PER_LONG to an 'unsigned long' variable.
[ tglx: Changed related function arguments to unsigned long and got rid
of the _cbm extra step ]
Fixes: 72d505056604 ("x86/intel_rdt: Add utilities to test pseudo-locked region possibility")
Fixes: 49f7b4efa110 ("x86/intel_rdt: Enable setting of exclusive mode")
Fixes: d9b48c86eb38 ("x86/intel_rdt: Display resource groups' allocations' size in bytes")
Fixes: 95f0b77efa57 ("x86/intel_rdt: Initialize new resource group with sane defaults")
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/69a428613a53f10e80594679ac726246020ff94f.1538686926.git.reinette.chatre@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Replace "fallthru" with a proper "fall through" annotation.
This fix is part of the ongoing efforts to enabling
-Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Replace "fallthru" with a proper "fall through" annotation.
This fix is part of the ongoing efforts to enabling
-Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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arch/sparc/vdso/Makefile is a replica of arch/x86/entry/vdso/Makefile.
Clean-up the Makefile in the same way as I did for x86:
- Remove unnecessary export
- Put the generated linker script to $(obj)/ instead of $(src)/
- Simplify cmd_vdso2c
The corresponding x86 commits are:
- 61615faf0a89 ("x86/build/vdso: Remove unnecessary export in Makefile")
- 1742ed2088cc ("x86/build/vdso: Put generated linker scripts to $(obj)/")
- c5fcdbf15523 ("x86/build/vdso: Simplify 'cmd_vdso2c'")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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A null check before a kfree is redundant, so remove it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In the quest to remove all stack VLA usage from the kernel[1], this
allocates a fixed size array for the maximum number of cookies and
adds a runtime sanity check.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1
RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Use the of_get_child_by_name() helper instead of open coding searching
for the '/options' node. This removes directly accessing the name
pointer as well.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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On Sun Ultra 5, it happens that the dot clock is not set up properly for
some videomodes. For example, if we set the videomode "r1024x768x60" in
the firmware, Linux would incorrectly set a videomode with refresh rate
180Hz when booting (suprisingly, my LCD monitor can display it, although
display quality is very low).
The reason is this: Older mach64 cards set the divider in the register
VCLK_POST_DIV. The register has four 2-bit fields (the field that is
actually used is specified in the lowest two bits of the register
CLOCK_CNTL). The 2 bits select divider "1, 2, 4, 8". On newer mach64 cards,
there's another bit added - the top four bits of PLL_EXT_CNTL extend the
divider selection, so we have possible dividers "1, 2, 4, 8, 3, 5, 6, 12".
The Linux driver clears the top four bits of PLL_EXT_CNTL and never sets
them, so it can work regardless if the card supports them. However, the
sparc64 firmware may set these extended dividers during boot - and the
mach64 driver detects incorrect dot clock in this case.
This patch makes the driver read the additional divider bit from
PLL_EXT_CNTL and calculate the initial refresh rate properly.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Ville Syrjälä <syrjala@sci.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The commit ca460b3c9627 ("percpu: introduce bitmap metadata blocks")
introduced bitmap metadata blocks. These metadata blocks are allocated
whenever a new chunk is created, but they are never freed. Fix it.
Fixes: ca460b3c9627 ("percpu: introduce bitmap metadata blocks")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dennis Zhou <dennis@kernel.org>
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When reflinking sub-file ranges, a data corruption can occur when
the source file range includes a partial EOF block. This shares the
unknown data beyond EOF into the second file at a position inside
EOF, exposing stale data in the second file.
XFS only supports whole block sharing, but we still need to
support whole file reflink correctly. Hence if the reflink
request includes the last block of the souce file, only proceed with
the reflink operation if it lands at or past the destination file's
current EOF. If it lands within the destination file EOF, reject the
entire request with -EINVAL and make the caller go the hard way.
This avoids the data corruption vector, but also avoids disruption
of returning EINVAL to userspace for the common case of whole file
cloning.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
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A deduplication data corruption is Exposed by fstests generic/505 on
XFS. It is caused by extending the block match range to include the
partial EOF block, but then allowing unknown data beyond EOF to be
considered a "match" to data in the destination file because the
comparison is only made to the end of the source file. This corrupts
the destination file when the source extent is shared with it.
XFS only supports whole block dedupe, but we still need to appear to
support whole file dedupe correctly. Hence if the dedupe request
includes the last block of the souce file, don't include it in the
actual XFS dedupe operation. If the rest of the range dedupes
successfully, then report the partial last block as deduped, too, so
that userspace sees it as a successful dedupe rather than return
EINVAL because we can't dedupe unaligned blocks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
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Reproducer, assuming 2M of hugetlbfs available:
Hugetlbfs mounted, size=2M and option user=testuser
# mount | grep ^hugetlbfs
hugetlbfs on /dev/hugepages type hugetlbfs (rw,pagesize=2M,user=dan)
# sysctl vm.nr_hugepages=1
vm.nr_hugepages = 1
# grep Huge /proc/meminfo
AnonHugePages: 0 kB
ShmemHugePages: 0 kB
HugePages_Total: 1
HugePages_Free: 1
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
Hugetlb: 2048 kB
Code:
#include <sys/mman.h>
#include <stddef.h>
#define SIZE 2*1024*1024
int main()
{
void *ptr;
ptr = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_HUGETLB | MAP_ANONYMOUS, -1, 0);
madvise(ptr, SIZE, MADV_DONTDUMP);
madvise(ptr, SIZE, MADV_DODUMP);
}
Compile and strace:
mmap(NULL, 2097152, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB, -1, 0) = 0x7ff7c9200000
madvise(0x7ff7c9200000, 2097152, MADV_DONTDUMP) = 0
madvise(0x7ff7c9200000, 2097152, MADV_DODUMP) = -1 EINVAL (Invalid argument)
hugetlbfs pages have VM_DONTEXPAND in the VmFlags driver pages based on
author testing with analysis from Florian Weimer[1].
The inclusion of VM_DONTEXPAND into the VM_SPECIAL defination was a
consequence of the large useage of VM_DONTEXPAND in device drivers.
A consequence of [2] is that VM_DONTEXPAND marked pages are unable to be
marked DODUMP.
A user could quite legitimately madvise(MADV_DONTDUMP) their hugetlbfs
memory for a while and later request that madvise(MADV_DODUMP) on the same
memory. We correct this omission by allowing madvice(MADV_DODUMP) on
hugetlbfs pages.
[1] https://stackoverflow.com/questions/52548260/madvisedodump-on-the-same-ptr-size-as-a-successful-madvisedontdump-fails-wit
[2] commit 0103bd16fb90 ("mm: prepare VM_DONTDUMP for using in drivers")
Link: http://lkml.kernel.org/r/20180930054629.29150-1-daniel@linux.ibm.com
Link: https://lists.launchpad.net/maria-discuss/msg05245.html
Fixes: 0103bd16fb90 ("mm: prepare VM_DONTDUMP for using in drivers")
Reported-by: Kenneth Penza <kpenza@gmail.com>
Signed-off-by: Daniel Black <daniel@linux.ibm.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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In dlm_init_lockres() we access and modify res->tracking and
dlm->tracking_list without holding dlm->track_lock. This can cause list
corruptions and can end up in kernel panic.
Fix this by locking res->tracking and dlm->tracking_list with
dlm->track_lock instead of dlm->spinlock.
Link: http://lkml.kernel.org/r/1529951192-4686-1-git-send-email-ashish.samant@oracle.com
Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Reviewed-by: Changwei Ge <ge.changwei@h3c.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Acked-by: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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do_shrink_slab() returns unsigned long value, and the placing into int
variable cuts high bytes off. Then we compare ret and 0xfffffffe (since
SHRINK_EMPTY is converted to ret type).
Thus a large number of objects returned by do_shrink_slab() may be
interpreted as SHRINK_EMPTY, if low bytes of their value are equal to
0xfffffffe. Fix that by declaration ret as unsigned long in these
functions.
Link: http://lkml.kernel.org/r/153813407177.17544.14888305435570723973.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reported-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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5dd0b16cdaff ("mm/vmstat: Make NR_TLB_REMOTE_FLUSH_RECEIVED available even
on UP") made the availability of the NR_TLB_REMOTE_FLUSH* counters inside
the kernel unconditional to reduce #ifdef soup, but (either to avoid
showing dummy zero counters to userspace, or because that code was missed)
didn't update the vmstat_array, meaning that all following counters would
be shown with incorrect values.
This only affects kernel builds with
CONFIG_VM_EVENT_COUNTERS=y && CONFIG_DEBUG_TLBFLUSH=y && CONFIG_SMP=n.
Link: http://lkml.kernel.org/r/20181001143138.95119-2-jannh@google.com
Fixes: 5dd0b16cdaff ("mm/vmstat: Make NR_TLB_REMOTE_FLUSH_RECEIVED available even on UP")
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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7a9cdebdcc17 ("mm: get rid of vmacache_flush_all() entirely") removed the
VMACACHE_FULL_FLUSHES statistics, but didn't remove the corresponding
entry in vmstat_text. This causes an out-of-bounds access in
vmstat_show().
Luckily this only affects kernels with CONFIG_DEBUG_VM_VMACACHE=y, which
is probably very rare.
Link: http://lkml.kernel.org/r/20181001143138.95119-1-jannh@google.com
Fixes: 7a9cdebdcc17 ("mm: get rid of vmacache_flush_all() entirely")
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Currently, you can use /proc/self/task/*/stack to cause a stack walk on
a task you control while it is running on another CPU. That means that
the stack can change under the stack walker. The stack walker does
have guards against going completely off the rails and into random
kernel memory, but it can interpret random data from your kernel stack
as instruction pointers and stack pointers. This can cause exposure of
kernel stack contents to userspace.
Restrict the ability to inspect kernel stacks of arbitrary tasks to root
in order to prevent a local attacker from exploiting racy stack unwinding
to leak kernel task stack contents. See the added comment for a longer
rationale.
There don't seem to be any users of this userspace API that can't
gracefully bail out if reading from the file fails. Therefore, I believe
that this change is unlikely to break things. In the case that this patch
does end up needing a revert, the next-best solution might be to fake a
single-entry stack based on wchan.
Link: http://lkml.kernel.org/r/20180927153316.200286-1-jannh@google.com
Fixes: 2ec220e27f50 ("proc: add /proc/*/stack")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ken Chen <kenchen@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
ARM64 architecture also supports 32MB and 512MB HugeTLB page sizes. This
just adds mmap() system call argument encoding for them.
Link: http://lkml.kernel.org/r/1537841300-6979-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
split_huge_page_to_list() fails on HugeTLB pages. I was experimenting
with moving 32MB contig HugeTLB pages on arm64 (with a debug patch
applied) and hit the following stack trace when the kernel crashed.
[ 3732.462797] Call trace:
[ 3732.462835] split_huge_page_to_list+0x3b0/0x858
[ 3732.462913] migrate_pages+0x728/0xc20
[ 3732.462999] soft_offline_page+0x448/0x8b0
[ 3732.463097] __arm64_sys_madvise+0x724/0x850
[ 3732.463197] el0_svc_handler+0x74/0x110
[ 3732.463297] el0_svc+0x8/0xc
[ 3732.463347] Code: d1000400 f90b0e60 f2fbd5a2 a94982a1 (f9000420)
When unmap_and_move[_huge_page]() fails due to lack of memory, the
splitting should happen only for transparent huge pages not for HugeTLB
pages. PageTransHuge() returns true for both THP and HugeTLB pages.
Hence the conditonal check should test PagesHuge() flag to make sure that
given pages is not a HugeTLB one.
Link: http://lkml.kernel.org/r/1537798495-4996-1-git-send-email-anshuman.khandual@arm.com
Fixes: 94723aafb9 ("mm: unclutter THP migration")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
This uses ERR_CAST() instead of an open-coded cast, as it is casting
across structure pointers, which upsets __randomize_layout:
ipc/shm.c: In function `shm_lock':
ipc/shm.c:209:9: note: randstruct: casting between randomized structure pointer types (ssa): `struct shmid_kernel' and `struct kern_ipc_perm'
return (void *)ipcp;
^~~~~~~~~~~~
Link: http://lkml.kernel.org/r/20180919180722.GA15073@beast
Fixes: 82061c57ce93 ("ipc: drop ipc_lock()")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
get_user_pages_fast() will return negative value if no pages were pinned,
then be converted to a unsigned, which is compared to zero, giving the
wrong result.
Link: http://lkml.kernel.org/r/20180921095015.26088-1-yuehaibing@huawei.com
Fixes: 09e35a4a1ca8 ("mm/gup_benchmark: handle gup failures")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
A transparent huge page is represented by a single entry on an LRU list.
Therefore, we can only make unevictable an entire compound page, not
individual subpages.
If a user tries to mlock() part of a huge page, we want the rest of the
page to be reclaimable.
We handle this by keeping PTE-mapped huge pages on normal LRU lists: the
PMD on border of VM_LOCKED VMA will be split into PTE table.
Introduction of THP migration breaks[1] the rules around mlocking THP
pages. If we had a single PMD mapping of the page in mlocked VMA, the
page will get mlocked, regardless of PTE mappings of the page.
For tmpfs/shmem it's easy to fix by checking PageDoubleMap() in
remove_migration_pmd().
Anon THP pages can only be shared between processes via fork(). Mlocked
page can only be shared if parent mlocked it before forking, otherwise CoW
will be triggered on mlock().
For Anon-THP, we can fix the issue by munlocking the page on removing PTE
migration entry for the page. PTEs for the page will always come after
mlocked PMD: rmap walks VMAs from oldest to newest.
Test-case:
#include <unistd.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <linux/mempolicy.h>
#include <numaif.h>
int main(void)
{
unsigned long nodemask = 4;
void *addr;
addr = mmap((void *)0x20000000UL, 2UL << 20, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_LOCKED, -1, 0);
if (fork()) {
wait(NULL);
return 0;
}
mlock(addr, 4UL << 10);
mbind(addr, 2UL << 20, MPOL_PREFERRED | MPOL_F_RELATIVE_NODES,
&nodemask, 4, MPOL_MF_MOVE);
return 0;
}
[1] https://lkml.kernel.org/r/CAOMGZ=G52R-30rZvhGxEbkTw7rLLwBGadVYeo--iizcD3upL3A@mail.gmail.com
Link: http://lkml.kernel.org/r/20180917133816.43995-1-kirill.shutemov@linux.intel.com
Fixes: 616b8371539a ("mm: thp: enable thp migration in generic path")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [4.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
ocfs2_duplicate_clusters_by_page() may crash if one of the extent's pages
is dirty. When a page has not been written back, it is still in dirty
state. If ocfs2_duplicate_clusters_by_page() is called against the dirty
page, the crash happens.
To fix this bug, we can just unlock the page and wait until the page until
its not dirty.
The following is the backtrace:
kernel BUG at /root/code/ocfs2/refcounttree.c:2961!
[exception RIP: ocfs2_duplicate_clusters_by_page+822]
__ocfs2_move_extent+0x80/0x450 [ocfs2]
? __ocfs2_claim_clusters+0x130/0x250 [ocfs2]
ocfs2_defrag_extent+0x5b8/0x5e0 [ocfs2]
__ocfs2_move_extents_range+0x2a4/0x470 [ocfs2]
ocfs2_move_extents+0x180/0x3b0 [ocfs2]
? ocfs2_wait_for_recovery+0x13/0x70 [ocfs2]
ocfs2_ioctl_move_extents+0x133/0x2d0 [ocfs2]
ocfs2_ioctl+0x253/0x640 [ocfs2]
do_vfs_ioctl+0x90/0x5f0
SyS_ioctl+0x74/0x80
do_syscall_64+0x74/0x140
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Once we find the page is dirty, we do not wait until it's clean, rather we
use write_one_page() to write it back
Link: http://lkml.kernel.org/r/20180829074740.9438-1-lchen@suse.com
[lchen@suse.com: update comments]
Link: http://lkml.kernel.org/r/20180830075041.14879-1-lchen@suse.com
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Larry Chen <lchen@suse.com>
Acked-by: Changwei Ge <ge.changwei@h3c.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
When fixing an issue with PMD sharing and migration, it was discovered via
code inspection that other callers of huge_pmd_unshare potentially have an
issue with cache and tlb flushing.
Use the routine adjust_range_if_pmd_sharing_possible() to calculate worst
case ranges for mmu notifiers. Ensure that this range is flushed if
huge_pmd_unshare succeeds and unmaps a PUD_SUZE area.
Link: http://lkml.kernel.org/r/20180823205917.16297-3-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
The page migration code employs try_to_unmap() to try and unmap the source
page. This is accomplished by using rmap_walk to find all vmas where the
page is mapped. This search stops when page mapcount is zero. For shared
PMD huge pages, the page map count is always 1 no matter the number of
mappings. Shared mappings are tracked via the reference count of the PMD
page. Therefore, try_to_unmap stops prematurely and does not completely
unmap all mappings of the source page.
This problem can result is data corruption as writes to the original
source page can happen after contents of the page are copied to the target
page. Hence, data is lost.
This problem was originally seen as DB corruption of shared global areas
after a huge page was soft offlined due to ECC memory errors. DB
developers noticed they could reproduce the issue by (hotplug) offlining
memory used to back huge pages. A simple testcase can reproduce the
problem by creating a shared PMD mapping (note that this must be at least
PUD_SIZE in size and PUD_SIZE aligned (1GB on x86)), and using
migrate_pages() to migrate process pages between nodes while continually
writing to the huge pages being migrated.
To fix, have the try_to_unmap_one routine check for huge PMD sharing by
calling huge_pmd_unshare for hugetlbfs huge pages. If it is a shared
mapping it will be 'unshared' which removes the page table entry and drops
the reference on the PMD page. After this, flush caches and TLB.
mmu notifiers are called before locking page tables, but we can not be
sure of PMD sharing until page tables are locked. Therefore, check for
the possibility of PMD sharing before locking so that notifiers can
prepare for the worst possible case.
Link: http://lkml.kernel.org/r/20180823205917.16297-2-mike.kravetz@oracle.com
[mike.kravetz@oracle.com: make _range_in_vma() a static inline]
Link: http://lkml.kernel.org/r/6063f215-a5c8-2f0c-465a-2c515ddc952d@oracle.com
Fixes: 39dde65c9940 ("shared page table for hugetlb page")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
When offloading the L3 and L4 csum computation on TX, we need to extract
the l3_proto from the ethtype, independently of the presence of a vlan
tag.
The actual driver uses skb->protocol as-is, resulting in packets with
the wrong L4 checksum being sent when there's a vlan tag in the packet
header and checksum offloading is enabled.
This commit makes use of vlan_protocol_get() to get the correct ethtype
regardless the presence of a vlan tag.
Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
In rawv6_send_hdrinc(), in order to avoid an extra dst_hold(), we
directly assign the dst to skb and set passed in dst to NULL to avoid
double free.
However, in error case, we free skb and then do stats update with the
dst pointer passed in. This causes use-after-free on the dst.
Fix it by taking rcu read lock right before dst could get released to
make sure dst does not get freed until the stats update is done.
Note: we don't have this issue in ipv4 cause dst is not used for stats
update in v4.
Syzkaller reported following crash:
BUG: KASAN: use-after-free in rawv6_send_hdrinc net/ipv6/raw.c:692 [inline]
BUG: KASAN: use-after-free in rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921
Read of size 8 at addr ffff8801d95ba730 by task syz-executor0/32088
CPU: 1 PID: 32088 Comm: syz-executor0 Not tainted 4.19.0-rc2+ #93
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113
print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
rawv6_send_hdrinc net/ipv6/raw.c:692 [inline]
rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921
inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
___sys_sendmsg+0x7fd/0x930 net/socket.c:2114
__sys_sendmsg+0x11d/0x280 net/socket.c:2152
__do_sys_sendmsg net/socket.c:2161 [inline]
__se_sys_sendmsg net/socket.c:2159 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f83756edc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f83756ee6d4 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 0000000020003840 RDI: 0000000000000004
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4b30 R14: 00000000004c90b1 R15: 0000000000000000
Allocated by task 32088:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554
dst_alloc+0xbb/0x1d0 net/core/dst.c:105
ip6_dst_alloc+0x35/0xa0 net/ipv6/route.c:353
ip6_rt_cache_alloc+0x247/0x7b0 net/ipv6/route.c:1186
ip6_pol_route+0x8f8/0xd90 net/ipv6/route.c:1895
ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2093
fib6_rule_lookup+0x277/0x860 net/ipv6/fib6_rules.c:122
ip6_route_output_flags+0x2c5/0x350 net/ipv6/route.c:2121
ip6_route_output include/net/ip6_route.h:88 [inline]
ip6_dst_lookup_tail+0xe27/0x1d60 net/ipv6/ip6_output.c:951
ip6_dst_lookup_flow+0xc8/0x270 net/ipv6/ip6_output.c:1079
rawv6_sendmsg+0x12d9/0x4630 net/ipv6/raw.c:905
inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
___sys_sendmsg+0x7fd/0x930 net/socket.c:2114
__sys_sendmsg+0x11d/0x280 net/socket.c:2152
__do_sys_sendmsg net/socket.c:2161 [inline]
__se_sys_sendmsg net/socket.c:2159 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 5356:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
__cache_free mm/slab.c:3498 [inline]
kmem_cache_free+0x83/0x290 mm/slab.c:3756
dst_destroy+0x267/0x3c0 net/core/dst.c:141
dst_destroy_rcu+0x16/0x19 net/core/dst.c:154
__rcu_reclaim kernel/rcu/rcu.h:236 [inline]
rcu_do_batch kernel/rcu/tree.c:2576 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline]
__rcu_process_callbacks kernel/rcu/tree.c:2847 [inline]
rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864
__do_softirq+0x30b/0xad8 kernel/softirq.c:292
Fixes: 1789a640f556 ("raw: avoid two atomics in xmit")
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Per ARC TLS ABI, r25 is designated TP (thread pointer register).
However so far kernel didn't do any special treatment, like setting up
usermode r25, even for CLONE_SETTLS. We instead relied on libc runtime
to do this, in say clone libc wrapper [1]. This was deliberate to keep
kernel ABI agnostic (userspace could potentially change TP, specially
for different ARC ISA say ARCompact vs. ARCv2 with different spare
registers etc)
However userspace setting up r25, after clone syscall opens a race, if
child is not scheduled and gets a signal instead. It starts off in
userspace not in clone but in a signal handler and anything TP sepcific
there such as pthread_self() fails which showed up with uClibc
testsuite nptl/tst-kill6 [2]
Fix this by having kernel populate r25 to TP value. So this locks in
ABI, but it was not going to change anyways, and fwiw is same for both
ARCompact (arc700 core) and ARCvs (HS3x cores)
[1] https://cgit.uclibc-ng.org/cgi/cgit/uclibc-ng.git/tree/libc/sysdeps/linux/arc/clone.S
[2] https://github.com/wbx-github/uclibc-ng-test/blob/master/test/nptl/tst-kill6.c
Fixes: ARC STAR 9001378481
Cc: stable@vger.kernel.org
Reported-by: Nikita Sobolev <sobolev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
|
|
A number of TC attributes are processed without proper validation
(e.g., length checks). Add a tca policy for all input attributes and use
when invoking nlmsg_parse.
The 2 Fixes tags below cover the latest additions. The other attributes
are a string (KIND), nested attribute (OPTIONS which does seem to have
validation in most cases), for dumps only or a flag.
Fixes: 5bc1701881e39 ("net: sched: introduce multichain support for filters")
Fixes: d47a6b0e7c492 ("net: sched: introduce ingress/egress block index attributes for qdisc")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Currently, rtnl_fdb_dump() assumes the family header is 'struct ifinfomsg',
which is not always true -- 'struct ndmsg' is used by iproute2 ('ip neigh').
The problem is, the function bails out early if nlmsg_parse() fails, which
does occur for iproute2 usage of 'struct ndmsg' because the payload length
is shorter than the family header alone (as 'struct ifinfomsg' is assumed).
This breaks backward compatibility with userspace -- nothing is sent back.
Some examples with iproute2 and netlink library for go [1]:
1) $ bridge fdb show
33:33:00:00:00:01 dev ens3 self permanent
01:00:5e:00:00:01 dev ens3 self permanent
33:33:ff:15:98:30 dev ens3 self permanent
This one works, as it uses 'struct ifinfomsg'.
fdb_show() @ iproute2/bridge/fdb.c
"""
.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
...
if (rtnl_dump_request(&rth, RTM_GETNEIGH, [...]
"""
2) $ ip --family bridge neigh
RTNETLINK answers: Invalid argument
Dump terminated
This one fails, as it uses 'struct ndmsg'.
do_show_or_flush() @ iproute2/ip/ipneigh.c
"""
.n.nlmsg_type = RTM_GETNEIGH,
.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
"""
3) $ ./neighlist
< no output >
This one fails, as it uses 'struct ndmsg'-based.
neighList() @ netlink/neigh_linux.go
"""
req := h.newNetlinkRequest(unix.RTM_GETNEIGH, [...]
msg := Ndmsg{
"""
The actual breakage was introduced by commit 0ff50e83b512 ("net: rtnetlink:
bail out from rtnl_fdb_dump() on parse error"), because nlmsg_parse() fails
if the payload length (with the _actual_ family header) is less than the
family header length alone (which is assumed, in parameter 'hdrlen').
This is true in the examples above with struct ndmsg, with size and payload
length shorter than struct ifinfomsg.
However, that commit just intends to fix something under the assumption the
family header is indeed an 'struct ifinfomsg' - by preventing access to the
payload as such (via 'ifm' pointer) if the payload length is not sufficient
to actually contain it.
The assumption was introduced by commit 5e6d24358799 ("bridge: netlink dump
interface at par with brctl"), to support iproute2's 'bridge fdb' command
(not 'ip neigh') which indeed uses 'struct ifinfomsg', thus is not broken.
So, in order to unbreak the 'struct ndmsg' family headers and still allow
'struct ifinfomsg' to continue to work, check for the known message sizes
used with 'struct ndmsg' in iproute2 (with zero or one attribute which is
not used in this function anyway) then do not parse the data as ifinfomsg.
Same examples with this patch applied (or revert/before the original fix):
$ bridge fdb show
33:33:00:00:00:01 dev ens3 self permanent
01:00:5e:00:00:01 dev ens3 self permanent
33:33:ff:15:98:30 dev ens3 self permanent
$ ip --family bridge neigh
dev ens3 lladdr 33:33:00:00:00:01 PERMANENT
dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT
dev ens3 lladdr 33:33:ff:15:98:30 PERMANENT
$ ./neighlist
netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x33, 0x33, 0x0, 0x0, 0x0, 0x1}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}
netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x1, 0x0, 0x5e, 0x0, 0x0, 0x1}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}
netlink.Neigh{LinkIndex:2, Family:7, State:128, Type:0, Flags:2, IP:net.IP(nil), HardwareAddr:net.HardwareAddr{0x33, 0x33, 0xff, 0x15, 0x98, 0x30}, LLIPAddr:net.IP(nil), Vlan:0, VNI:0}
Tested on mainline (v4.19-rc6) and net-next (3bd09b05b068).
References:
[1] netlink library for go (test-case)
https://github.com/vishvananda/netlink
$ cat ~/go/src/neighlist/main.go
package main
import ("fmt"; "syscall"; "github.com/vishvananda/netlink")
func main() {
neighs, _ := netlink.NeighList(0, syscall.AF_BRIDGE)
for _, neigh := range neighs { fmt.Printf("%#v\n", neigh) }
}
$ export GOPATH=~/go
$ go get github.com/vishvananda/netlink
$ go build neighlist
$ ~/go/src/neighlist/neighlist
Thanks to David Ahern for suggestions to improve this patch.
Fixes: 0ff50e83b512 ("net: rtnetlink: bail out from rtnl_fdb_dump() on parse error")
Fixes: 5e6d24358799 ("bridge: netlink dump interface at par with brctl")
Reported-by: Aidan Obley <aobley@pivotal.io>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
In yam_ioctl(), the concrete ioctl command is firstly copied from the
user-space buffer 'ifr->ifr_data' to 'ioctl_cmd' and checked through the
following switch statement. If the command is not as expected, an error
code EINVAL is returned. In the following execution the buffer
'ifr->ifr_data' is copied again in the cases of the switch statement to
specific data structures according to what kind of ioctl command is
requested. However, after the second copy, no re-check is enforced on the
newly-copied command. Given that the buffer 'ifr->ifr_data' is in the user
space, a malicious user can race to change the command between the two
copies. This way, the attacker can inject inconsistent data and cause
undefined behavior.
This patch adds a re-check in each case of the switch statement if there is
a second copy in that case, to re-check whether the command obtained in the
second copy is the same as the one in the first copy. If not, an error code
EINVAL will be returned.
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Fixes the following Sparse warnings:
net/bpfilter/bpfilter_kern.c:62:21: warning: cast removes address space
of expression
net/bpfilter/bpfilter_kern.c:101:49: warning: Using plain integer as
NULL pointer
Signed-off-by: Shanthosh RK <shanthosh.rk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
In cxgb_extension_ioctl(), the command of the ioctl is firstly copied from
the user-space buffer 'useraddr' to 'cmd' and checked through the
switch statement. If the command is not as expected, an error code
EOPNOTSUPP is returned. In the following execution, i.e., the cases of the
switch statement, the whole buffer of 'useraddr' is copied again to a
specific data structure, according to what kind of command is requested.
However, after the second copy, there is no re-check on the newly-copied
command. Given that the buffer 'useraddr' is in the user space, a malicious
user can race to change the command between the two copies. By doing so,
the attacker can supply malicious data to the kernel and cause undefined
behavior.
This patch adds a re-check in each case of the switch statement if there is
a second copy in that case, to re-check whether the command obtained in the
second copy is the same as the one in the first copy. If not, an error code
EINVAL is returned.
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
When I wrote commit 468f6eafa6c4 ("bpf: fix 32-bit ALU op verification"), I
assumed that, in order to emulate 64-bit arithmetic with 32-bit logic, it
is sufficient to just truncate the output to 32 bits; and so I just moved
the register size coercion that used to be at the start of the function to
the end of the function.
That assumption is true for almost every op, but not for 32-bit right
shifts, because those can propagate information towards the least
significant bit. Fix it by always truncating inputs for 32-bit ops to 32
bits.
Also get rid of the coerce_reg_to_size() after the ALU op, since that has
no effect.
Fixes: 468f6eafa6c4 ("bpf: fix 32-bit ALU op verification")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
Fix a commit 8a8158c85e1e ("MIPS: memset.S: EVA & fault support for
small_memset") regression and remove assembly warnings:
arch/mips/lib/memset.S: Assembler messages:
arch/mips/lib/memset.S:243: Warning: Macro instruction expanded into multiple instructions in a branch delay slot
triggering with the CPU_DADDI_WORKAROUNDS option set and this code:
PTR_SUBU a2, t1, a0
jr ra
PTR_ADDIU a2, 1
This is because with that option in place the DADDIU instruction, which
the PTR_ADDIU CPP macro expands to, becomes a GAS macro, which in turn
expands to an LI/DADDU (or actually ADDIU/DADDU) sequence:
13c: 01a4302f dsubu a2,t1,a0
140: 03e00008 jr ra
144: 24010001 li at,1
148: 00c1302d daddu a2,a2,at
...
Correct this by switching off the `noreorder' assembly mode and letting
GAS schedule this jump's delay slot, as there is nothing special about
it that would require manual scheduling. With this change in place
correct code is produced:
13c: 01a4302f dsubu a2,t1,a0
140: 24010001 li at,1
144: 03e00008 jr ra
148: 00c1302d daddu a2,a2,at
...
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 8a8158c85e1e ("MIPS: memset.S: EVA & fault support for small_memset")
Patchwork: https://patchwork.linux-mips.org/patch/20833/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: stable@vger.kernel.org # 4.17+
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Only use the mapped IP to find inline frames, but keep using the
unmapped IP for the callchain cursor. This ensures we properly show the
unmapped IP when displaying a frame we received via the
dso__parse_addr_inlines API for a module which does not contain
sufficient debug symbols to show the srcline.
This is another follow-up to commit 19610184693c ("perf script: Show
virtual addresses instead of offsets").
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Fixes: 19610184693c ("perf script: Show virtual addresses instead of offsets")
Link: http://lkml.kernel.org/r/20180926135207.30263-2-milian.wolff@kdab.com
Link: http://lkml.kernel.org/r/20181002073949.3297-1-milian.wolff@kdab.com
[ Squashed a fix from Milian for a problem reported by Ravi, fixed up space damage ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The functions vbin_printf() and bstr_printf() are used by trace_printk() to
try to keep the overhead down during printing. trace_printk() uses
vbin_printf() at the time of execution, as it only scans the fmt string to
record the printf values into the buffer, and then uses vbin_printf() to do
the conversions to print the string based on the format and the saved
values in the buffer.
This is an issue for dereferenced pointers, as before commit 841a915d20c7b,
the processing of the pointer could happen some time after the pointer value
was recorded (reading the trace buffer). This means the processing of the
value at a later time could show different results, or even crash the
system, if the pointer no longer existed.
Commit 841a915d20c7b addressed this by processing dereferenced pointers at
the time of execution and save the result in the ring buffer as a string.
The bstr_printf() would then treat these pointers as normal strings, and
print the value. But there was an off-by-one bug here, where after
processing the argument, it move the pointer only "strlen(arg)" which made
the arg pointer not point to the next argument in the ring buffer, but
instead point to the nul character of the last argument. This causes any
values after a dereferenced pointer to be corrupted.
Cc: stable@vger.kernel.org
Fixes: 841a915d20c7b ("vsprintf: Do not have bprintf dereference pointers")
Reported-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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When building in ClearLinux using 'make PYTHON=python3' with gcc 8.2.1
it fails with:
GEN /tmp/build/perf/python/perf.so
In file included from /usr/include/python3.7m/Python.h:126,
from /git/linux/tools/perf/util/python.c:2:
/usr/include/python3.7m/import.h:58:24: error: redundant redeclaration of ‘_PyImport_AddModuleObject’ [-Werror=redundant-decls]
PyAPI_FUNC(PyObject *) _PyImport_AddModuleObject(PyObject *, PyObject *);
^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/python3.7m/import.h:47:24: note: previous declaration of ‘_PyImport_AddModuleObject’ was here
PyAPI_FUNC(PyObject *) _PyImport_AddModuleObject(PyObject *name,
^~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
error: command 'gcc' failed with exit status 1
And indeed there is a redundant declaration in that Python.h file, one
with parameter names and the other without, so just add
-Wno-error=redundant-decls to the python setup instructions.
Now perf builds with gcc in ClearLinux with the following Dockerfile:
# docker.io/acmel/linux-perf-tools-build-clearlinux:latest
FROM docker.io/clearlinux:latest
MAINTAINER Arnaldo Carvalho de Melo <acme@kernel.org>
RUN swupd update && \
swupd bundle-add sysadmin-basic-dev
RUN mkdir -m 777 -p /git /tmp/build/perf /tmp/build/objtool /tmp/build/linux && \
groupadd -r perfbuilder && \
useradd -m -r -g perfbuilder perfbuilder && \
chown -R perfbuilder.perfbuilder /tmp/build/ /git/
USER perfbuilder
COPY rx_and_build.sh /
ENV EXTRA_MAKE_ARGS=PYTHON=python3
ENTRYPOINT ["/rx_and_build.sh"]
Now to figure out why the build fails with clang, that is present in the
above container as detected by the rx_and_build.sh script:
clang version 6.0.1 (tags/RELEASE_601/final)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/sbin
make: Entering directory '/git/linux/tools/perf'
BUILD: Doing 'make -j4' parallel build
HOSTCC /tmp/build/perf/fixdep.o
HOSTLD /tmp/build/perf/fixdep-in.o
LINK /tmp/build/perf/fixdep
Auto-detecting system features:
... dwarf: [ OFF ]
... dwarf_getlocations: [ OFF ]
... glibc: [ OFF ]
... gtk2: [ OFF ]
... libaudit: [ OFF ]
... libbfd: [ OFF ]
... libelf: [ OFF ]
... libnuma: [ OFF ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ OFF ]
... libpython: [ OFF ]
... libslang: [ OFF ]
... libcrypto: [ OFF ]
... libunwind: [ OFF ]
... libdw-dwarf-unwind: [ OFF ]
... zlib: [ OFF ]
... lzma: [ OFF ]
... get_cpuid: [ OFF ]
... bpf: [ OFF ]
Makefile.config:331: *** No gnu/libc-version.h found, please install glibc-dev[el]. Stop.
make[1]: *** [Makefile.perf:206: sub-make] Error 2
make: *** [Makefile:70: all] Error 2
make: Leaving directory '/git/linux/tools/perf'
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thiago Macieira <thiago.macieira@intel.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-c3khb9ac86s00qxzjrueomme@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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With commit 2ea626306810 ("powerpc/topology: Get topology for shared
processors at boot"), kdump kernel on shared LPAR may crash.
The necessary conditions are
- Shared LPAR with at least 2 nodes having memory and CPUs.
- Memory requirement for kdump kernel must be met by the first N-1
nodes where there are at least N nodes with memory and CPUs.
Example numactl of such a machine.
$ numactl -H
available: 5 nodes (0,2,5-7)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 2 cpus:
node 2 size: 255 MB
node 2 free: 189 MB
node 5 cpus: 24 25 26 27 28 29 30 31
node 5 size: 4095 MB
node 5 free: 4024 MB
node 6 cpus: 0 1 2 3 4 5 6 7 16 17 18 19 20 21 22 23
node 6 size: 6353 MB
node 6 free: 5998 MB
node 7 cpus: 8 9 10 11 12 13 14 15 32 33 34 35 36 37 38 39
node 7 size: 7640 MB
node 7 free: 7164 MB
node distances:
node 0 2 5 6 7
0: 10 40 40 40 40
2: 40 10 40 40 40
5: 40 40 10 40 40
6: 40 40 40 10 20
7: 40 40 40 20 10
Steps to reproduce.
1. Load / start kdump service.
2. Trigger a kdump (for example : echo c > /proc/sysrq-trigger)
When booting a kdump kernel with 2048M:
kexec: Starting switchover sequence.
I'm in purgatory
Using 1TB segments
hash-mmu: Initializing hash mmu with SLB
Linux version 4.19.0-rc5-master+ (srikar@linux-xxu6) (gcc version 4.8.5 (SUSE Linux)) #1 SMP Thu Sep 27 19:45:00 IST 2018
Found initrd at 0xc000000009e70000:0xc00000000ae554b4
Using pSeries machine description
-----------------------------------------------------
ppc64_pft_size = 0x1e
phys_mem_size = 0x88000000
dcache_bsize = 0x80
icache_bsize = 0x80
cpu_features = 0x000000ff8f5d91a7
possible = 0x0000fbffcf5fb1a7
always = 0x0000006f8b5c91a1
cpu_user_features = 0xdc0065c2 0xef000000
mmu_features = 0x7c006001
firmware_features = 0x00000007c45bfc57
htab_hash_mask = 0x7fffff
physical_start = 0x8000000
-----------------------------------------------------
numa: NODE_DATA [mem 0x87d5e300-0x87d67fff]
numa: NODE_DATA(0) on node 6
numa: NODE_DATA [mem 0x87d54600-0x87d5e2ff]
Top of RAM: 0x88000000, Total RAM: 0x88000000
Memory hole size: 0MB
Zone ranges:
DMA [mem 0x0000000000000000-0x0000000087ffffff]
DMA32 empty
Normal empty
Movable zone start for each node
Early memory node ranges
node 6: [mem 0x0000000000000000-0x0000000087ffffff]
Could not find start_pfn for node 0
Initmem setup node 0 [mem 0x0000000000000000-0x0000000000000000]
On node 0 totalpages: 0
Initmem setup node 6 [mem 0x0000000000000000-0x0000000087ffffff]
On node 6 totalpages: 34816
Unable to handle kernel paging request for data at address 0x00000060
Faulting instruction address: 0xc000000008703a54
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 11 PID: 1 Comm: swapper/11 Not tainted 4.19.0-rc5-master+ #1
NIP: c000000008703a54 LR: c000000008703a38 CTR: 0000000000000000
REGS: c00000000b673440 TRAP: 0380 Not tainted (4.19.0-rc5-master+)
MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 24022022 XER: 20000002
CFAR: c0000000086fc238 IRQMASK: 0
GPR00: c000000008703a38 c00000000b6736c0 c000000009281900 0000000000000000
GPR04: 0000000000000000 0000000000000000 fffffffffffff001 c00000000b660080
GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000220
GPR12: 0000000000002200 c000000009e51400 0000000000000000 0000000000000008
GPR16: 0000000000000000 c000000008c152e8 c000000008c152a8 0000000000000000
GPR20: c000000009422fd8 c000000009412fd8 c000000009426040 0000000000000008
GPR24: 0000000000000000 0000000000000000 c000000009168bc8 c000000009168c78
GPR28: c00000000b126410 0000000000000000 c00000000916a0b8 c00000000b126400
NIP [c000000008703a54] bus_add_device+0x84/0x1e0
LR [c000000008703a38] bus_add_device+0x68/0x1e0
Call Trace:
[c00000000b6736c0] [c000000008703a38] bus_add_device+0x68/0x1e0 (unreliable)
[c00000000b673740] [c000000008700194] device_add+0x454/0x7c0
[c00000000b673800] [c00000000872e660] __register_one_node+0xb0/0x240
[c00000000b673860] [c00000000839a6bc] __try_online_node+0x12c/0x180
[c00000000b673900] [c00000000839b978] try_online_node+0x58/0x90
[c00000000b673930] [c0000000080846d8] find_and_online_cpu_nid+0x158/0x190
[c00000000b673a10] [c0000000080848a0] numa_update_cpu_topology+0x190/0x580
[c00000000b673c00] [c000000008d3f2e4] smp_cpus_done+0x94/0x108
[c00000000b673c70] [c000000008d5c00c] smp_init+0x174/0x19c
[c00000000b673d00] [c000000008d346b8] kernel_init_freeable+0x1e0/0x450
[c00000000b673dc0] [c0000000080102e8] kernel_init+0x28/0x160
[c00000000b673e30] [c00000000800b65c] ret_from_kernel_thread+0x5c/0x80
Instruction dump:
60000000 60000000 e89e0020 7fe3fb78 4bff87d5 60000000 7c7d1b79 4082008c
e8bf0050 e93e0098 3b9f0010 2fa50000 <e8690060> 38630018 419e0114 7f84e378
---[ end trace 593577668c2daa65 ]---
However a regular kernel with 4096M (2048 gets reserved for crash
kernel) boots properly.
Unlike regular kernels, which mark all available nodes as online,
kdump kernel only marks just enough nodes as online and marks the rest
as offline at boot. However kdump kernel boots with all available
CPUs. With Commit 2ea626306810 ("powerpc/topology: Get topology for
shared processors at boot"), all CPUs are onlined on their respective
nodes at boot time. try_online_node() tries to online the offline
nodes but fails as all needed subsystems are not yet initialized.
As part of fix, detect and skip early onlining of a offline node.
Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot")
Reported-by: Pavithra Prakash <pavrampu@in.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Recently we implemented show_user_instructions() which dumps the code
around the NIP when a user space process dies with an unhandled
signal. This was modelled on the x86 code, and we even went so far as
to implement the exact same bug, namely that if the user process
crashed with its NIP pointing into the kernel we will dump kernel text
to dmesg. eg:
bad-bctr[2996]: segfault (11) at c000000000010000 nip c000000000010000 lr 12d0b0894 code 1
bad-bctr[2996]: code: fbe10068 7cbe2b78 7c7f1b78 fb610048 38a10028 38810020 fb810050 7f8802a6
bad-bctr[2996]: code: 3860001c f8010080 48242371 60000000 <7c7b1b79> 4082002c e8010080 eb610048
This was discovered on x86 by Jann Horn and fixed in commit
342db04ae712 ("x86/dumpstack: Don't dump kernel memory based on usermode RIP").
Fix it by checking the adjusted NIP value (pc) and number of
instructions against USER_DS, and bail if we fail the check, eg:
bad-bctr[2969]: segfault (11) at c000000000010000 nip c000000000010000 lr 107930894 code 1
bad-bctr[2969]: Bad NIP, not dumping instructions.
Fixes: 88b0fe175735 ("powerpc: Add show_user_instructions()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|