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Anatoly continues to find issues with fuzzed squashfs images.
This time, corrupt, missing, or undersized data for the page filling
wasn't checked for, because the squashfs_{copy,read}_cache() functions
did the squashfs_copy_data() call without checking the resulting data
size.
Which could result in the page cache pages being incompletely filled in,
and no error indication to the user space reading garbage data.
So make a helper function for the "fill in pages" case, because the
exact same incomplete sequence existed in two places.
[ I should have made a squashfs branch for these things, but I didn't
intend to start doing them in the first place.
My historical connection through cramfs is why I got into looking at
these issues at all, and every time I (continue to) think it's a
one-off.
Because _this_ time is always the last time. Right? - Linus ]
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Amit Pundir and Youling in parallel reported crashes with recent
mainline kernels running Android:
F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
F DEBUG : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key
F DEBUG : Revision: '0'
F DEBUG : ABI: 'arm'
F DEBUG : pid: 2261, tid: 2261, name: zygote >>> zygote <<<
F DEBUG : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008
... <snip> ...
F DEBUG : backtrace:
F DEBUG : #00 pc 00001c04 /system/lib/libc.so (memset+48)
F DEBUG : #01 pc 0010c513 /system/lib/libart.so (create_mspace_with_base+82)
F DEBUG : #02 pc 0015c601 /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40)
F DEBUG : #03 pc 0015c3ed /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string<char, std::__ 1::char_traits<char>, std::__1::allocator<char>> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36)
...
This was bisected back to commit bfd40eaff5ab ("mm: fix
vma_is_anonymous() false-positives").
create_mspace_with_base() in the trace above, utilizes ashmem, and with
ashmem, for shared mappings we use shmem_zero_setup(), which sets the
vma->vm_ops to &shmem_vm_ops. But for private ashmem mappings nothing
sets the vma->vm_ops.
Looking at the problematic patch, it seems to add a requirement that one
call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be
used. Using the dummy_vm_ops seem to triggger SIGBUS when traversing
unmapped pages.
Thus, this patch adds a call to vma_set_anonymous() for ashmem private
mappings and seems to avoid the reported problem.
Fixes: bfd40eaff5ab ("mm: fix vma_is_anonymous() false-positives")
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Colin Cross <ccross@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Reported-by: Amit Pundir <amit.pundir@linaro.org>
Reported-by: Youling 257 <youling257@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit bfd40eaff5ab ("mm: fix vma_is_anonymous() false-positives") made
newly allocated vma's have a dummy vm_ops field so that they wouldn't be
mistaken for anonymous mappings, and if you wanted an anonymous vma you
had to explicitly say so by calling "vma_set_anonymous()" on it.
However, it missed the two special vmas that ia64 processes have: the
register backing store and the NaT page. So they wouldn't actually act
like anonymous ranges, and page faults on them caused a SIGBUS rather
than the creation of a new anon page in them.
That obviously will make any ia64 binary very unhappy indeed, and the
boot fails early.
Fixes: bfd40eaff5ab ("mm: fix vma_is_anonymous() false-positives")
Reported-by: Tony Luck <tony.luck@intel.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull audit fix from Paul Moore:
"A single small audit fix to guard against memory allocation failures
when logging information about a kernel module load.
It's small, easy to understand, and self-contained; while nothing is
zero risk, this should be pretty low"
* tag 'audit-pr-20180731' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: fix potential null dereference 'context->module.name'
Pull SCSI fixes from James Bottomley:
"Nine fixes, five in the qla2xxx driver, the most serious of which is
the uninitialized list head crash which can be observed in most
systems under a sufficiently loaded low memory environment.
The two sg fixes are minor but obvious and two target ones which seem
reasonable but not high impact"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: qla2xxx: Return error when TMF returns
scsi: qla2xxx: Fix ISP recovery on unload
scsi: qla2xxx: Fix driver unload by shutting down chip
scsi: qla2xxx: Fix NPIV deletion by calling wait_for_sess_deletion
scsi: qla2xxx: Fix unintialized List head crash
scsi: sg: update comment for blk_get_request()
scsi: sg: fix minor memory leak in error path
scsi: libiscsi: fix possible NULL pointer dereference in case of TMF
scsi: target: iscsi: cxgbit: fix max iso npdu calculation
The variable 'context->module.name' may be null pointer when
kmalloc return null, so it's better to check it before using
to avoid null dereference.
Another one more thing this patch does is using kstrdup instead
of (kmalloc + strcpy), and signal a lost record via audit_log_lost.
Cc: stable@vger.kernel.org # 4.11
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull virtio fixes from Michael Tsirkin:
"Some bugfixes that seem important and safe enough to merge at the last
minute"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_balloon: fix another race between migration and ballooning
tools/virtio: add kmalloc_array stub
tools/virtio: add dma barrier stubs
Propagate the task management completion status properly to avoid
unnecessary waits for commands to complete.
Fixes: faef62d13463 ("[SCSI] qla2xxx: Fix Task Management command asynchronous handling")
Cc: <stable@vger.kernel.org>
Signed-off-by: Anil Gurumurthy <anil.gurumurthy@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The audit_filter_rules() function in auditsc.c compared the session ID
with the credentials of the current task, while it should use the
credentials of the task given to audit_filter_rules() as a parameter
(tsk).
GitHub issue:
https://github.com/linux-audit/audit-kernel/issues/82
Fixes: 8fae47705685 ("audit: add support for session ID user filter")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
[PM: not user visible, dropped stable]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull ACPI fixes from Rafael Wysocki:
"These fix a recent ACPICA regression affecting control method
execution at the table level and an earlier hibernation regression in
the ACPI driver for Intel SoCs (LPSS) that was missed by a previous
fix in this cycle.
Specifics:
- Fix a recent ACPICA regression introduced by a previous fix that
caused control method execution at the table level to be mishandled
by mistake (Erik Schmauss).
- Fix a hibernation regression from the 4.15 cycle in the ACPI driver
for Intel SoCs (LPSS) that caused the platform firmware to be
confused during resume from hibernation by the driver's PM quirks
which was fixed for system-wide suspend/resume (ACPI S3) earlier in
this cycle, but that previous fix missed the hibernation (ACPI S4)
case (Rafael Wysocki)"
* tag 'acpi-urgent-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPICA: AML Parser: ignore control method status in module-level code
ACPI / LPSS: Avoid PM quirks on suspend and resume from hibernation
Kernel panic when with high memory pressure, calltrace looks like,
PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java"
#0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb
#1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942
#2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30
#3 [ffff881ec7ed7778] oops_end at ffffffff816902c8
#4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46
#5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc
#6 [ffff881ec7ed7838] __node_set at ffffffff81680300
#7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f
#8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5
#9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8
[exception RIP: _raw_spin_lock_irqsave+47]
RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046
RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8
RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008
RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098
R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
It happens in the pagefault and results in double pagefault
during compacting pages when memory allocation fails.
Analysed the vmcore, the page leads to second pagefault is corrupted
with _mapcount=-256, but private=0.
It's caused by the race between migration and ballooning, and lock
missing in virtballoon_migratepage() of virtio_balloon driver.
This patch fix the bug.
Fixes: e22504296d4f64f ("virtio_balloon: introduce migration primitives to balloon pages")
Cc: stable@vger.kernel.org
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Huang Chong <huang.chong@zte.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
During unload process, the chip can encounter problem where a FW dump would
be captured. For this case, the full reset sequence will be skip to bring
the chip back to full operational state.
Fixes: e315cd28b9ef ("[SCSI] qla2xxx: Code changes for qla data structure refactoring")
Cc: <stable@vger.kernel.org>
Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use the existing audit_log_session_info() function rather than
hardcoding its functionality.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull networking fixes from David Miller:
"Several smallish fixes, I don't think any of this requires another -rc
but I'll leave that up to you:
1) Don't leak uninitialzed bytes to userspace in xfrm_user, from Eric
Dumazet.
2) Route leak in xfrm_lookup_route(), from Tommi Rantala.
3) Premature poll() returns in AF_XDP, from Björn Töpel.
4) devlink leak in netdevsim, from Jakub Kicinski.
5) Don't BUG_ON in fib_compute_spec_dst, the condition can
legitimately happen. From Lorenzo Bianconi.
6) Fix some spectre v1 gadgets in generic socket code, from Jeremy
Cline.
7) Don't allow user to bind to out of range multicast groups, from
Dmitry Safonov with a follow-up by Dmitry Safonov.
8) Fix metrics leak in fib6_drop_pcpu_from(), from Sabrina Dubroca"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits)
netlink: Don't shift with UB on nlk->ngroups
net/ipv6: fix metrics leak
xen-netfront: wait xenbus state change when load module manually
can: ems_usb: Fix memory leak on ems_usb_disconnect()
openvswitch: meter: Fix setting meter id for new entries
netlink: Do not subscribe to non-existent groups
NET: stmmac: align DMA stuff to largest cache line length
tcp_bbr: fix bw probing to raise in-flight data for very small BDPs
net: socket: Fix potential spectre v1 gadget in sock_is_registered
net: socket: fix potential spectre v1 gadget in socketcall
net: mdio-mux: bcm-iproc: fix wrong getter and setter pair
ipv4: remove BUG_ON() from fib_compute_spec_dst
enic: handle mtu change for vf properly
net: lan78xx: fix rx handling before first packet is send
nfp: flower: fix port metadata conversion bug
bpf: use GFP_ATOMIC instead of GFP_KERNEL in bpf_parse_prog()
bpf: fix bpf_skb_load_bytes_relative pkt length check
perf build: Build error in libbpf missing initialization
net: ena: Fix use of uninitialized DMA address bits field
bpf: btf: Use exact btf value_size match in map_check_btf()
...