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  1. Apr 16, 2022
    • Minchan Kim's avatar
      mm: fix unexpected zeroed page mapping with zram swap · e914d8f0
      Minchan Kim authored 
      Two processes under CLONE_VM cloning, user process can be corrupted by
seeing zeroed page unexpectedly.

      CPU A                        CPU B

  do_swap_page                do_swap_page
  SWP_SYNCHRONOUS_IO path     SWP_SYNCHRONOUS_IO path
  swap_readpage valid data
    swap_slot_free_notify
      delete zram entry
                              swap_readpage zeroed(invalid) data
                              pte_lock
                              map the *zero data* to userspace
                              pte_unlock
  pte_lock
  if (!pte_same)
    goto out_nomap;
  pte_unlock
  return and next refault will
  read zeroed data

The swap_slot_free_notify is bogus for CLONE_VM case since it doesn't
increase the refcount of swap slot at copy_mm so it couldn't catch up
whether it's safe or not to discard data from backing device.  In the
case, only the lock it could rely on to synchronize swap slot freeing is
page table lock.  Thus, this patch gets rid of the swap_slot_free_notify
function.  With this patch, CPU A will see correct data.

      CPU A                        CPU B

  do_swap_page                do_swap_page
  SWP_SYNCHRONOUS_IO path     SWP_SYNCHRONOUS_IO path
                              swap_readpage original data
                              pte_lock
                              map the original data
                              swap_free
                                swap_range_free
                                  bd_disk->fops->swap_slot_free_notify
  swap_readpage read zeroed data
                              pte_unlock
  pte_lock
  if (!pte_same)
    goto out_nomap;
  pte_unlock
  return
  on next refault will see mapped data by CPU B

The concern of the patch would increase memory consumption since it
could keep wasted memory with compressed form in zram as well as
uncompressed form in address space.  However, most of cases of zram uses
no readahead and do_swap_page is followed by swap_free so it will free
the compressed form from in zram quickly.

Link: https://lkml.kernel.org/r/YjTVVxIAsnKAXjTd@google.com
Fixes: 0bcac06f

 ("mm, swap: skip swapcache for swapin of synchronous device")
Reported-by: default avatarIvan Babrou <ivan@cloudflare.com>
Tested-by: default avatarIvan Babrou <ivan@cloudflare.com>
Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: David Hildenbrand <david@redhat.com>
Cc: <stable@vger.kernel.org>	[4.14+]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e914d8f0
    • Juergen Gross's avatar
      mm, page_alloc: fix build_zonerefs_node() · e553f62f
      Juergen Gross authored 
      Since commit 6aa303de ("mm, vmscan: only allocate and reclaim from
zones with pages managed by the buddy allocator") only zones with free
memory are included in a built zonelist.  This is problematic when e.g.
all memory of a zone has been ballooned out when zonelists are being
rebuilt.

The decision whether to rebuild the zonelists when onlining new memory
is done based on populated_zone() returning 0 for the zone the memory
will be added to.  The new zone is added to the zonelists only, if it
has free memory pages (managed_zone() returns a non-zero value) after
the memory has been onlined.  This implies, that onlining memory will
always free the added pages to the allocator immediately, but this is
not true in all cases: when e.g. running as a Xen guest the onlined new
memory will be added only to the ballooned memory list, it will be freed
only when the guest is being ballooned up afterwards.

Another problem with using managed_zone() for the decision whether a
zone is being added to the zonelists is, that a zone with all memory
used will in fact be removed from all zonelists in case the zonelists
happen to be rebuilt.

Use populated_zone() when building a zonelist as it has been done before
that commit.

There was a report that QubesOS (based on Xen) is hitting this problem.
Xen has switched to use the zone device functionality in kernel 5.9 and
QubesOS wants to use memory hotplugging for guests in order to be able
to start a guest with minimal memory and expand it as needed.  This was
the report leading to the patch.

Link: https://lkml.kernel.org/r/20220407120637.9035-1-jgross@suse.com
Fixes: 6aa303de

 ("mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator")
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reported-by: default avatarMarek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: default avatarWei Yang <richard.weiyang@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e553f62f
    • Marco Elver's avatar
      mm, kfence: support kmem_dump_obj() for KFENCE objects · 2dfe63e6
      Marco Elver authored 
      Calling kmem_obj_info() via kmem_dump_obj() on KFENCE objects has been
producing garbage data due to the object not actually being maintained
by SLAB or SLUB.

Fix this by implementing __kfence_obj_info() that copies relevant
information to struct kmem_obj_info when the object was allocated by
KFENCE; this is called by a common kmem_obj_info(), which also calls the
slab/slub/slob specific variant now called __kmem_obj_info().

For completeness, kmem_dump_obj() now displays if the object was
allocated by KFENCE.

Link: https://lore.kernel.org/all/20220323090520.GG16885@xsang-OptiPlex-9020/
Link: https://lkml.kernel.org/r/20220406131558.3558585-1-elver@google.com
Fixes: b89fb5ef ("mm, kfence: insert KFENCE hooks for SLUB")
Fixes: d3fb45f3

 ("mm, kfence: insert KFENCE hooks for SLAB")
Signed-off-by: default avatarMarco Elver <elver@google.com>
Reviewed-by: default avatarHyeonggon Yoo <42.hyeyoo@gmail.com>
Reported-by: default avatarkernel test robot <oliver.sang@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>	[slab]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2dfe63e6
    • Vincenzo Frascino's avatar
      kasan: fix hw tags enablement when KUNIT tests are disabled · b1add418
      Vincenzo Frascino authored 
      Kasan enables hw tags via kasan_enable_tagging() which based on the mode
passed via kernel command line selects the correct hw backend.
kasan_enable_tagging() is meant to be invoked indirectly via the cpu
features framework of the architectures that support these backends.
Currently the invocation of this function is guarded by
CONFIG_KASAN_KUNIT_TEST which allows the enablement of the correct backend
only when KUNIT tests are enabled in the kernel.

This inconsistency was introduced in commit:

  ed6d7444 ("kasan: test: support async (again) and asymm modes for HW_TAGS")

... and prevents to enable MTE on arm64 when KUNIT tests for kasan hw_tags are
disabled.

Fix the issue making sure that the CONFIG_KASAN_KUNIT_TEST guard does not
prevent the correct invocation of kasan_enable_tagging().

Link: https://lkml.kernel.org/r/20220408124323.10028-1-vincenzo.frascino@arm.com
Fixes: ed6d7444

 ("kasan: test: support async (again) and asymm modes for HW_TAGS")
Signed-off-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: default avatarAndrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b1add418
    • Zqiang's avatar
      irq_work: use kasan_record_aux_stack_noalloc() record callstack · 25934fcf
      Zqiang authored 
      On PREEMPT_RT kernel and KASAN is enabled.  the kasan_record_aux_stack()
may call alloc_pages(), and the rt-spinlock will be acquired, if currently
in atomic context, will trigger warning:

  BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 239, name: bootlogd
  Preemption disabled at:
  [<ffffffffbab1a531>] rt_mutex_slowunlock+0xa1/0x4e0
  CPU: 3 PID: 239 Comm: bootlogd Tainted: G        W 5.17.1-rt17-yocto-preempt-rt+ #105
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
  Call Trace:
     __might_resched.cold+0x13b/0x173
     rt_spin_lock+0x5b/0xf0
     get_page_from_freelist+0x20c/0x1610
     __alloc_pages+0x25e/0x5e0
     __stack_depot_save+0x3c0/0x4a0
     kasan_save_stack+0x3a/0x50
     __kasan_record_aux_stack+0xb6/0xc0
     kasan_record_aux_stack+0xe/0x10
     irq_work_queue_o...
      25934fcf
    • Axel Rasmussen's avatar
      mm/secretmem: fix panic when growing a memfd_secret · f9b141f9
      Axel Rasmussen authored 
      

When one tries to grow an existing memfd_secret with ftruncate, one gets
a panic [1].  For example, doing the following reliably induces the
panic:

    fd = memfd_secret();

    ftruncate(fd, 10);
    ptr = mmap(NULL, 10, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
    strcpy(ptr, "123456789");

    munmap(ptr, 10);
    ftruncate(fd, 20);

The basic reason for this is, when we grow with ftruncate, we call down
into simple_setattr, and then truncate_inode_pages_range, and eventually
we try to zero part of the memory.  The normal truncation code does this
via the direct map (i.e., it calls page_address() and hands that to
memset()).

For memfd_secret though, we specifically don't map our pages via the
direct map (i.e.  we call set_direct_map_invalid_noflush() on every
fault).  So the address returned by page_address() isn't useful, and
when we try to memset() with it we panic.

This patch avoids the panic by implementing a custom setattr for
memfd_secret, which detects resizes specifically (setting the size for
the first time works just fine, since there are no existing pages to try
to zero), and rejects them with EINVAL.

One could argue growing should be supported, but I think that will
require a significantly more lengthy change.  So, I propose a minimal
fix for the benefit of stable kernels, and then perhaps to extend
memfd_secret to support growing in a separate patch.

[1]:

  BUG: unable to handle page fault for address: ffffa0a889277028
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD afa01067 P4D afa01067 PUD 83f909067 PMD 83f8bf067 PTE 800ffffef6d88060
  Oops: 0002 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
  CPU: 0 PID: 281 Comm: repro Not tainted 5.17.0-dbg-DEV #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  RIP: 0010:memset_erms+0x9/0x10
  Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01
  RSP: 0018:ffffb932c09afbf0 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffffda63c4249dc0 RCX: 0000000000000fd8
  RDX: 0000000000000fd8 RSI: 0000000000000000 RDI: ffffa0a889277028
  RBP: ffffb932c09afc00 R08: 0000000000001000 R09: ffffa0a889277028
  R10: 0000000000020023 R11: 0000000000000000 R12: ffffda63c4249dc0
  R13: ffffa0a890d70d98 R14: 0000000000000028 R15: 0000000000000fd8
  FS:  00007f7294899580(0000) GS:ffffa0af9bc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffa0a889277028 CR3: 0000000107ef6006 CR4: 0000000000370ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? zero_user_segments+0x82/0x190
   truncate_inode_partial_folio+0xd4/0x2a0
   truncate_inode_pages_range+0x380/0x830
   truncate_setsize+0x63/0x80
   simple_setattr+0x37/0x60
   notify_change+0x3d8/0x4d0
   do_sys_ftruncate+0x162/0x1d0
   __x64_sys_ftruncate+0x1c/0x20
   do_syscall_64+0x44/0xa0
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  Modules linked in: xhci_pci xhci_hcd virtio_net net_failover failover virtio_blk virtio_balloon uhci_hcd ohci_pci ohci_hcd evdev ehci_pci ehci_hcd 9pnet_virtio 9p netfs 9pnet
  CR2: ffffa0a889277028

[lkp@intel.com: secretmem_iops can be static]
Signed-off-by: default avatarkernel test robot <lkp@intel.com>
[axelrasmussen@google.com: return EINVAL]

Link: https://lkml.kernel.org/r/20220324210909.1843814-1-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220412193023.279320-1-axelrasmussen@google.com


Signed-off-by: default avatarAxel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f9b141f9
    • Hugh Dickins's avatar
      tmpfs: fix regressions from wider use of ZERO_PAGE · 1bdec44b
      Hugh Dickins authored 
      Chuck Lever reported fsx-based xfstests generic 075 091 112 127 failing
when 5.18-rc1 NFS server exports tmpfs: bisected to recent tmpfs change.

Whilst nfsd_splice_action() does contain some questionable handling of
repeated pages, and Chuck was able to work around there, history from
Mark Hemment makes clear that there might be similar dangers elsewhere:
it was not a good idea for me to pass ZERO_PAGE down to unknown actors.

Revert shmem_file_read_iter() to using ZERO_PAGE for holes only when
iter_is_iovec(); in other cases, use the more natural iov_iter_zero()
instead of copy_page_to_iter().

We would use iov_iter_zero() throughout, but the x86 clear_user() is not
nearly so well optimized as copy to user (dd of 1T sparse tmpfs file
takes 57 seconds rather than 44 seconds).

And now pagecache_init() does not need to SetPageUptodate(ZERO_PAGE(0)):
which had caused boot failure on arm noMMU STM32F7 and STM32H7 boards

Link: https://lkml.kernel.org/r/9a978571-8648-e830-5735-1f4748ce2e30@google.com
Fixes: 56a8c8eb

 ("tmpfs: do not allocate pages on read")
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Reported-by: default avatarPatrice CHOTARD <patrice.chotard@foss.st.com>
Reported-by: default avatarChuck Lever III <chuck.lever@oracle.com>
Tested-by: default avatarChuck Lever III <chuck.lever@oracle.com>
Cc: Mark Hemment <markhemm@googlemail.com>
Cc: Patrice CHOTARD <patrice.chotard@foss.st.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1bdec44b
    • Joe Perches's avatar
      MAINTAINERS: Broadcom internal lists aren't maintainers · 7fbd166a
      Joe Perches authored 
      Convert the broadcom internal list M: and L: entries to R: as exploder
email addresses are neither maintainers nor mailing lists.

Reorder the entries as necessary.

Link: https://lkml.kernel.org/r/04eb301f5b3adbefdd78e76657eff0acb3e3d87f.camel@perches.com


Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7fbd166a
  3. Apr 15, 2022
    • Linus Torvalds's avatar
      Merge tag 's390-5.18-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux · 115acbb5
      Linus Torvalds authored 
      Pull s390 fixes from Heiko Carstens:

 - Convert current_stack_pointer to a register alias like it is assumed
   if ARCH_HAS_CURRENT_STACK_POINTER is selected. The existing
   implementation as a function breaks CONFIG_HARDENED_USERCOPY
   sanity-checks

 - Get rid of -Warray-bounds warning within kexec code

 - Add minimal IBM z16 support by reporting a proper elf platform, and
   adding compile options

 - Update defconfigs

* tag 's390-5.18-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: enable CONFIG_HARDENED_USERCOPY in debug_defconfig
  s390: current_stack_pointer shouldn't be a function
  s390: update defconfigs
  s390/kexec: silence -Warray-bounds warning
  s390: allow to compile with z16 optimizations
  s390: add z16 elf platform
      115acbb5
    • Linus Torvalds's avatar
      Merge tag 'net-5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net · d20339fa
      Linus Torvalds authored 
      Pull networking fixes from Paolo Abeni:
 "Including fixes from wireless and netfilter.

  Current release - regressions:

   - smc: fix af_ops of child socket pointing to released memory

   - wifi: ath9k: fix usage of driver-private space in tx_info

  Previous releases - regressions:

   - ipv6: fix panic when forwarding a pkt with no in6 dev

   - sctp: use the correct skb for security_sctp_assoc_request

   - smc: fix NULL pointer dereference in smc_pnet_find_ib()

   - sched: fix initialization order when updating chain 0 head

   - phy: don't defer probe forever if PHY IRQ provider is missing

   - dsa: revert "net: dsa: setup master before ports"

   - dsa: felix: fix tagging protocol changes with multiple CPU ports

   - eth: ice:
      - fix use-after-free when freeing @rx_cpu_rmap
      - revert "iavf: fix deadlock occurrence during resetting VF
        interface"

   - eth: lan966x: stop processing the MAC entry is port is wrong

  Previous releases - always broken:

   - sched:
      - flower: fix parsing of ethertype following VLAN header
      - taprio: check if socket flags are valid

   - nfc: add flush_workqueue to prevent uaf

   - veth: ensure eth header is in skb's linear part

   - eth: stmmac: fix altr_tse_pcs function when using a fixed-link

   - eth: macb: restart tx only if queue pointer is lagging

   - eth: macvlan: fix leaking skb in source mode with nodst option"

* tag 'net-5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (52 commits)
  net: bcmgenet: Revert "Use stronger register read/writes to assure ordering"
  rtnetlink: Fix handling of disabled L3 stats in RTM_GETSTATS replies
  net: dsa: felix: fix tagging protocol changes with multiple CPU ports
  tun: annotate access to queue->trans_start
  nfc: nci: add flush_workqueue to prevent uaf
  net: dsa: realtek: don't parse compatible string for RTL8366S
  net: dsa: realtek: fix Kconfig to assure consistent driver linkage
  net: ftgmac100: access hardware register after clock ready
  Revert "net: dsa: setup master before ports"
  macvlan: Fix leaking skb in source mode with nodst option
  netfilter: nf_tables: nft_parse_register can return a negative value
  net: lan966x: Stop processing the MAC entry is port is wrong.
  net: lan966x: Fix when a port's upper is changed.
  net: lan966x: Fix IGMP snooping when frames have vlan tag
  net: lan966x: Update lan966x_ptp_get_nominal_value
  sctp: Initialize daddr on peeled off socket
  net/smc: Fix af_ops of child socket pointing to released memory
  net/smc: Fix NULL pointer dereference in smc_pnet_find_ib()
  net/smc: use memcpy instead of snprintf to avoid out of bounds read
  net: macb: Restart tx only if queue pointer is lagging
  ...
      d20339fa
    • Linus Torvalds's avatar
      Merge tag 'sound-5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound · b9b4c79e
      Linus Torvalds authored 
      Pull sound fixes from Takashi Iwai:
 "This became an unexpectedly large pull request due to various
  regression fixes in the previous kernels.

  The majority of fixes are a series of patches to address the
  regression at probe errors in devres'ed drivers, while there are yet
  more fixes for the x86 SG allocations and for USB-audio buffer
  management. In addition, a few HD-audio quirks and other small fixes
  are found"

* tag 'sound-5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (52 commits)
  ALSA: usb-audio: Limit max buffer and period sizes per time
  ALSA: memalloc: Add fallback SG-buffer allocations for x86
  ALSA: nm256: Don't call card private_free at probe error path
  ALSA: mtpav: Don't call card private_free at probe error path
  ALSA: rme9652: Fix the missing snd_card_free() call at probe error
  ALSA: hdspm: Fix the missing snd_card_free() call at probe error
  ALSA: hdsp: Fix the missing snd_card_free() call at probe error
  ALSA: oxygen: Fix the missing snd_card_free() call at probe error
  ALSA: lx6464es: Fix the missing snd_card_free() call at probe error
  ALSA: cmipci: Fix the missing snd_card_free() call at probe error
  ALSA: aw2: Fix the missing snd_card_free() call at probe error
  ALSA: als300: Fix the missing snd_card_free() call at probe error
  ALSA: lola: Fix the missing snd_card_free() call at probe error
  ALSA: bt87x: Fix the missing snd_card_free() call at probe error
  ALSA: sis7019: Fix the missing error handling
  ALSA: intel_hdmi: Fix the missing snd_card_free() call at probe error
  ALSA: via82xx: Fix the missing snd_card_free() call at probe error
  ALSA: sonicvibes: Fix the missing snd_card_free() call at probe error
  ALSA: rme96: Fix the missing snd_card_free() call at probe error
  ALSA: rme32: Fix the missing snd_card_free() call at probe error
  ...
      b9b4c79e
    • Linus Torvalds's avatar
      Merge tag 'for-5.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux · 722985e2
      Linus Torvalds authored 
      Pull btrfs fixes from David Sterba:
 "A few more code and warning fixes.

  There's one feature ioctl removal patch slated for 5.18 that did not
  make it to the main pull request. It's just a one-liner and the ioctl
  has a v2 that's in use for a long time, no point to postpone it to
  5.19.

  Late update:

   - remove balance v1 ioctl, superseded by v2 in 2012

  Fixes:

   - add back cgroup attribution for compressed writes

   - add super block write start/end annotations to asynchronous balance

   - fix root reference count on an error handling path

   - in zoned mode, activate zone at the chunk allocation time to avoid
     ENOSPC due to timing issues

   - fix delayed allocation accounting for direct IO

  Warning fixes:

   - simplify assertion condition in zoned check

   - remove an unused variable"

* tag 'for-5.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix btrfs_submit_compressed_write cgroup attribution
  btrfs: fix root ref counts in error handling in btrfs_get_root_ref
  btrfs: zoned: activate block group only for extent allocation
  btrfs: return allocated block group from do_chunk_alloc()
  btrfs: mark resumed async balance as writing
  btrfs: remove support of balance v1 ioctl
  btrfs: release correct delalloc amount in direct IO write path
  btrfs: remove unused variable in btrfs_{start,write}_dirty_block_groups()
  btrfs: zoned: remove redundant condition in btrfs_run_delalloc_range
      722985e2
    • Linus Torvalds's avatar
      Merge tag 'fscache-fixes-20220413' of... · ec9c57a7
      Linus Torvalds authored 
      Merge tag 'fscache-fixes-20220413' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache fixes from David Howells:
 "Here's a collection of fscache and cachefiles fixes and misc small
  cleanups. The two main fixes are:

   - Add a missing unmark of the inode in-use mark in an error path.

   - Fix a KASAN slab-out-of-bounds error when setting the xattr on a
     cachefiles volume due to the wrong length being given to memcpy().

  In addition, there's the removal of an unused parameter, removal of an
  unused Kconfig option, conditionalising a bit of procfs-related stuff
  and some doc fixes"

* tag 'fscache-fixes-20220413' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache: remove FSCACHE_OLD_API Kconfig option
  fscache: Use wrapper fscache_set_cache_state() directly when relinquishing
  fscache: Move fscache_cookies_seq_ops specific code under CONFIG_PROC_FS
  fscache: Remove the cookie parameter from fscache_clear_page_bits()
  docs: filesystems: caching/backend-api.rst: fix an object withdrawn API
  docs: filesystems: caching/backend-api.rst: correct two relinquish APIs use
  cachefiles: Fix KASAN slab-out-of-bounds in cachefiles_set_volume_xattr
  cachefiles: unmark inode in use in error path
      ec9c57a7
  5. Apr 14, 2022
  7. Apr 13, 2022
    • Lin Ma's avatar
      nfc: nci: add flush_workqueue to prevent uaf · ef27324e
      Lin Ma authored 
      Our detector found a concurrent use-after-free bug when detaching an
NCI device. The main reason for this bug is the unexpected scheduling
between the used delayed mechanism (timer and workqueue).

The race can be demonstrated below:

Thread-1                           Thread-2
                                 | nci_dev_up()
                                 |   nci_open_device()
                                 |     __nci_request(nci_reset_req)
                                 |       nci_send_cmd
                                 |         queue_work(cmd_work)
nci_unregister_device()          |
  nci_close_device()             | ...
    del_timer_sync(cmd_timer)[1] |
...                              | Worker
nci_free_device()                | nci_cmd_work()
  kfree(ndev)[3]                 |   mod_timer(cmd_timer)[2]

In short, the cleanup routine thought that the cmd_timer has already
been detached by [1] but the mod_timer can re-attach the timer [2], even
it is already released [3], resulting in UAF.

This UAF is easy to trigger, crash trace by POC is like below

[   66.703713] ==================================================================
[   66.703974] BUG: KASAN: use-after-free in enqueue_timer+0x448/0x490
[   66.703974] Write of size 8 at addr ffff888009fb7058 by task kworker/u4:1/33
[   66.703974]
[   66.703974] CPU: 1 PID: 33 Comm: kworker/u4:1 Not tainted 5.18.0-rc2 #5
[   66.703974] Workqueue: nfc2_nci_cmd_wq nci_cmd_work
[   66.703974] Call Trace:
[   66.703974]  <TASK>
[   66.703974]  dump_stack_lvl+0x57/0x7d
[   66.703974]  print_report.cold+0x5e/0x5db
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  kasan_report+0xbe/0x1c0
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  enqueue_timer+0x448/0x490
[   66.703974]  __mod_timer+0x5e6/0xb80
[   66.703974]  ? mark_held_locks+0x9e/0xe0
[   66.703974]  ? try_to_del_timer_sync+0xf0/0xf0
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x17b/0x410
[   66.703974]  ? queue_work_on+0x61/0x80
[   66.703974]  ? lockdep_hardirqs_on+0xbf/0x130
[   66.703974]  process_one_work+0x8bb/0x1510
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   66.703974]  ? pwq_dec_nr_in_flight+0x230/0x230
[   66.703974]  ? rwlock_bug.part.0+0x90/0x90
[   66.703974]  ? _raw_spin_lock_irq+0x41/0x50
[   66.703974]  worker_thread+0x575/0x1190
[   66.703974]  ? process_one_work+0x1510/0x1510
[   66.703974]  kthread+0x2a0/0x340
[   66.703974]  ? kthread_complete_and_exit+0x20/0x20
[   66.703974]  ret_from_fork+0x22/0x30
[   66.703974]  </TASK>
[   66.703974]
[   66.703974] Allocated by task 267:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  __kasan_kmalloc+0x81/0xa0
[   66.703974]  nci_allocate_device+0xd3/0x390
[   66.703974]  nfcmrvl_nci_register_dev+0x183/0x2c0
[   66.703974]  nfcmrvl_nci_uart_open+0xf2/0x1dd
[   66.703974]  nci_uart_tty_ioctl+0x2c3/0x4a0
[   66.703974]  tty_ioctl+0x764/0x1310
[   66.703974]  __x64_sys_ioctl+0x122/0x190
[   66.703974]  do_syscall_64+0x3b/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   66.703974]
[   66.703974] Freed by task 406:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  kasan_set_track+0x21/0x30
[   66.703974]  kasan_set_free_info+0x20/0x30
[   66.703974]  __kasan_slab_free+0x108/0x170
[   66.703974]  kfree+0xb0/0x330
[   66.703974]  nfcmrvl_nci_unregister_dev+0x90/0xd0
[   66.703974]  nci_uart_tty_close+0xdf/0x180
[   66.703974]  tty_ldisc_kill+0x73/0x110
[   66.703974]  tty_ldisc_hangup+0x281/0x5b0
[   66.703974]  __tty_hangup.part.0+0x431/0x890
[   66.703974]  tty_release+0x3a8/0xc80
[   66.703974]  __fput+0x1f0/0x8c0
[   66.703974]  task_work_run+0xc9/0x170
[   66.703974]  exit_to_user_mode_prepare+0x194/0x1a0
[   66.703974]  syscall_exit_to_user_mode+0x19/0x50
[   66.703974]  do_syscall_64+0x48/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae

To fix the UAF, this patch adds flush_workqueue() to ensure the
nci_cmd_work is finished before the following del_timer_sync.
This combination will promise the timer is actually detached.

Fixes: 6a2968aa

 ("NFC: basic NCI protocol implementation")
Signed-off-by: default avatarLin Ma <linma@zju.edu.cn>
Reviewed-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ef27324e
    • Alvin Šipraga's avatar
      net: dsa: realtek: don't parse compatible string for RTL8366S · 8e925de6
      Alvin Šipraga authored 
      This switch is not even supported, but if someone were to actually put
this compatible string "realtek,rtl8366s" in their device tree, they
would be greeted with a kernel panic because the probe function would
dereference NULL. So let's just remove it.

Link: https://lore.kernel.org/all/CACRpkdYdKZs0WExXc3=0yPNOwP+oOV60HRz7SRoGjZvYHaT=1g@mail.gmail.com/


Signed-off-by: default avatarAlvin Šipraga <alsi@bang-olufsen.dk>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8e925de6
    • Alvin Šipraga's avatar
      net: dsa: realtek: fix Kconfig to assure consistent driver linkage · 2511e0c8
      Alvin Šipraga authored 
      The kernel test robot reported a build failure:

or1k-linux-ld: drivers/net/dsa/realtek/realtek-smi.o:(.rodata+0x16c): undefined reference to `rtl8366rb_variant'

... with the following build configuration:

CONFIG_NET_DSA_REALTEK=y
CONFIG_NET_DSA_REALTEK_SMI=y
CONFIG_NET_DSA_REALTEK_RTL8365MB=y
CONFIG_NET_DSA_REALTEK_RTL8366RB=m

The problem here is that the realtek-smi interface driver gets built-in,
while the rtl8366rb switch subdriver gets built as a module, hence the
symbol rtl8366rb_variant is not reachable when defining the OF device
table in the interface driver.

The Kconfig dependencies don't help in this scenario because they just
say that the subdriver(s) depend on at least one interface driver. In
fact, the subdrivers don't depend on the interface drivers at all, and
can even be built even in their absence. Somewhat strangely, the
interface drivers can also be built in the absence of any subdriver,
BUT, if a subdriver IS enabled, then it must be reachable according to
the linkage of the interface driver: effectively what the IS_REACHABLE()
macro achieves. If it is not reachable, the above kind of linker error
will be observed.

Rather than papering over the above build error by simply using
IS_REACHABLE(), we can do a little better and admit that it is actually
the interface drivers that have a dependency on the subdrivers. So this
patch does exactly that. Specifically, we ensure that:

1. The interface drivers' Kconfig symbols must have a value no greater
   than the value of any subdriver Kconfig symbols.

2. The subdrivers should by default enable both interface drivers, since
   most users probably want at least one of them; those interface
   drivers can be explicitly disabled however.

What this doesn't do is prevent a user from building only a subdriver,
without any interface driver. To that end, add an additional line of
help in the menu to guide users in the right direction.

Link: https://lore.kernel.org/all/202204110757.XIafvVnj-lkp@intel.com/


Reported-by: default avatarkernel test robot <lkp@intel.com>
Fixes: aac94001

 ("net: dsa: realtek: add new mdio interface for drivers")
Signed-off-by: default avatarAlvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2511e0c8
    • David S. Miller's avatar
      Merge tag 'wireless-2022-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless · dad32cfe
      David S. Miller authored 
      

Kalle Valo says:

====================
wireless fixes for v5.18

First set of fixes for v5.18. Maintainers file updates, two
compilation warning fixes, one revert for ath11k and smaller fixes to
drivers and stack. All the usual stuff.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      dad32cfe
    • Dylan Hung's avatar
      net: ftgmac100: access hardware register after clock ready · 3d250452
      Dylan Hung authored 
      AST2600 MAC register 0x58 is writable only when the MAC clock is
enabled.  Usually, the MAC clock is enabled by the bootloader so
register 0x58 is set normally when the bootloader is involved.  To make
ast2600 ftgmac100 work without the bootloader, postpone the register
write until the clock is ready.

Fixes: 137d23ce

 ("net: ftgmac100: Fix Aspeed ast2600 TX hang issue")
Signed-off-by: default avatarDylan Hung <dylan_hung@aspeedtech.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3d250452
    • Vladimir Oltean's avatar
      Revert "net: dsa: setup master before ports" · 762c2998
      Vladimir Oltean authored 
      This reverts commit 11fd667d.

dsa_slave_change_mtu() updates the MTU of the DSA master and of the
associated CPU port, but only if it detects a change to the master MTU.

The blamed commit in the Fixes: tag below addressed a regression where
dsa_slave_change_mtu() would return early and not do anything due to
ds->ops->port_change_mtu() not being implemented.

However, that commit also had the effect that the master MTU got set up
to the correct value by dsa_master_setup(), but the associated CPU port's
MTU did not get updated. This causes breakage for drivers that rely on
the ->port_change_mtu() DSA call to account for the tagging overhead on
the CPU port, and don't set up the initial MTU during the setup phase.

Things actually worked before because they were in a fragile equilibrium
where dsa_slave_change_mtu() was called before dsa_master_setup() was.
So dsa_slave_change_mtu() could actually detect a change and update the
CPU port MTU too.

Restore the code to the way things used to work by reverting the reorder
of dsa_tree_setup_master() and dsa_tree_setup_ports(). That change did
not have a concrete motivation going for it anyway, it just looked
better.

Fixes: 066dfc42

 ("Revert "net: dsa: stop updating master MTU from master.c"")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      762c2998
    • Martin Willi's avatar
      macvlan: Fix leaking skb in source mode with nodst option · e16b8598
      Martin Willi authored 
      The MACVLAN receive handler clones skbs to all matching source MACVLAN
interfaces, before it passes the packet along to match on destination
based MACVLANs.

When using the MACVLAN nodst mode, passing the packet to destination based
MACVLANs is omitted and the handler returns with RX_HANDLER_CONSUMED.
However, the passed skb is not freed, leaking for any packet processed
with the nodst option.

Properly free the skb when consuming packets to fix that leak.

Fixes: 427f0c8c

 ("macvlan: Add nodst option to macvlan type source")
Signed-off-by: default avatarMartin Willi <martin@strongswan.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e16b8598
    • Takashi Iwai's avatar
      ALSA: usb-audio: Limit max buffer and period sizes per time · 24d0c9f0
      Takashi Iwai authored 
      In the previous fix, we increased the max buffer bytes from 1MB to 4MB
so that we can use bigger buffers for the modern HiFi devices with
higher rates, more channels and wider formats.  OTOH, extending this
has a concern that too big buffer is allowed for the lower rates, less
channels and narrower formats; when an application tries to allocate
as big buffer as possible, it'll lead to unexpectedly too huge size.

Also, we had a problem about the inconsistent max buffer and period
bytes for the implicit feedback mode when both streams have different
channels.  This was fixed by the (relatively complex) patch to reduce
the max buffer and period bytes accordingly.

This is an alternative fix for those, a patch to kill two birds with
one stone (*): instead of increasing the max buffer bytes blindly and
applying the reduction per channels, we simply use the hw constraints
for the buffer and period "time".  Meanwhile the max buffer and period
bytes are set unlimited instead.

Since the inconsistency of buffer (and period) bytes comes from the
difference of the channels in the tied streams, as long as we care
only about the buffer (and period) time, it doesn't matter; the buffer
time is same for different channels, although we still allow higher
buffer size.  Similarly, this will allow more buffer bytes for HiFi
devices while it also keeps the reasonable size for the legacy
devices, too.

As of this patch, the max period and buffer time are set to 1 and 2
seconds, which should be large enough for all possible use cases.

(*) No animals were harmed in the making of this patch.

Fixes: 98c27add ("ALSA: usb-audio: Cap upper limits of buffer/period bytes for implicit fb")
Fixes: fee2ec8c ("ALSA: usb-audio: Increase max buffer size")
Link: https://lore.kernel.org/r/20220412130740.18933-1-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      24d0c9f0
    • Takashi Iwai's avatar
      ALSA: memalloc: Add fallback SG-buffer allocations for x86 · 925ca893
      Takashi Iwai authored 
      The recent change for memory allocator replaced the SG-buffer handling
helper for x86 with the standard non-contiguous page handler.  This
works for most cases, but there is a corner case I obviously
overlooked, namely, the fallback of non-contiguous handler without
IOMMU.  When the system runs without IOMMU, the core handler tries to
use the continuous pages with a single SGL entry.  It works nicely for
most cases, but when the system memory gets fragmented, the large
allocation may fail frequently.

Ideally the non-contig handler could deal with the proper SG pages,
it's cumbersome to extend for now.  As a workaround, here we add new
types for (minimalistic) SG allocations, instead, so that the
allocator falls back to those types automatically when the allocation
with the standard API failed.

BTW, one better (but pretty minor) improvement from the previous
SG-buffer code is that this provides the proper mmap support without
the PCM's page fault handling.

Fixes: 2c95b92e ("ALSA: memalloc: Unify x86 SG-buffer handling (take#3)")
BugLink: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/2272
BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1198248
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220413054808.7547-1-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      925ca893
    • Linus Torvalds's avatar
      Merge tag 'hardening-v5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux · a1994480
      Linus Torvalds authored 
      Pull hardening fixes from Kees Cook:

 - latent_entropy: Use /dev/urandom instead of small GCC seed (Jason
   Donenfeld)

 - uapi/stddef.h: add missed include guards (Tadeusz Struk)

* tag 'hardening-v5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  gcc-plugins: latent_entropy: use /dev/urandom
  uapi/linux/stddef.h: Add include guards
      a1994480
    • Linus Torvalds's avatar
      Merge tag 'nfsd-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux · c1488c97
      Linus Torvalds authored 
      Pull nfsd fixes from Chuck Lever:

 - Fix a write performance regression

 - Fix crashes during request deferral on RDMA transports

* tag 'nfsd-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  SUNRPC: Fix the svc_deferred_event trace class
  SUNRPC: Fix NFSD's request deferral on RDMA transports
  nfsd: Clean up nfsd_file_put()
  nfsd: Fix a write performance regression
  SUNRPC: Return true/false (not 1/0) from bool functions
      c1488c97
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 453096eb
      Linus Torvalds authored 
      Pull kvm fixes from Paolo Bonzini:
 "x86:

   - Miscellaneous bugfixes

   - A small cleanup for the new workqueue code

   - Documentation syntax fix

  RISC-V:

   - Remove hgatp zeroing in kvm_arch_vcpu_put()

   - Fix alignment of the guest_hang() in KVM selftest

   - Fix PTE A and D bits in KVM selftest

   - Missing #include in vcpu_fp.c

  ARM:

   - Some PSCI fixes after introducing PSCIv1.1 and SYSTEM_RESET2

   - Fix the MMU write-lock not being taken on THP split

   - Fix mixed-width VM handling

   - Fix potential UAF when debugfs registration fails

   - Various selftest updates for all of the above"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (24 commits)
  KVM: x86: hyper-v: Avoid writing to TSC page without an active vCPU
  KVM: SVM: Do not activate AVIC for SEV-enabled guest
  Documentation: KVM: Add SPDX-License-Identifier tag
  selftests: kvm: add tsc_scaling_sync to .gitignore
  RISC-V: KVM: include missing hwcap.h into vcpu_fp
  KVM: selftests: riscv: Fix alignment of the guest_hang() function
  KVM: selftests: riscv: Set PTE A and D bits in VS-stage page table
  RISC-V: KVM: Don't clear hgatp CSR in kvm_arch_vcpu_put()
  selftests: KVM: Free the GIC FD when cleaning up in arch_timer
  selftests: KVM: Don't leak GIC FD across dirty log test iterations
  KVM: Don't create VM debugfs files outside of the VM directory
  KVM: selftests: get-reg-list: Add KVM_REG_ARM_FW_REG(3)
  KVM: avoid NULL pointer dereference in kvm_dirty_ring_push
  KVM: arm64: selftests: Introduce vcpu_width_config
  KVM: arm64: mixed-width check should be skipped for uninitialized vCPUs
  KVM: arm64: vgic: Remove unnecessary type castings
  KVM: arm64: Don't split hugepages outside of MMU write lock
  KVM: arm64: Drop unneeded minor version check from PSCI v1.x handler
  KVM: arm64: Actually prevent SMC64 SYSTEM_RESET2 from AArch32
  KVM: arm64: Generally disallow SMC64 for AArch32 guests
  ...
      453096eb
    • Linus Torvalds's avatar
      Merge tag 'media/v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media · 7083b89e
      Linus Torvalds authored 
      Pull media fixes from Mauro Carvalho Chehab:

 - a regression fix for si2157

 - a Kconfig dependency fix for imx-mipi-csis

 - fix the rockchip/rga driver probing logic

* tag 'media/v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: si2157: unknown chip version Si2147-A30 ROM 0x50
  media: platform: imx-mipi-csis: Add dependency on VIDEO_DEV
  media: rockchip/rga: do proper error checking in probe
      7083b89e
    • Mikulas Patocka's avatar
      stat: fix inconsistency between struct stat and struct compat_stat · 932aba1e
      Mikulas Patocka authored 
      struct stat (defined in arch/x86/include/uapi/asm/stat.h) has 32-bit
st_dev and st_rdev; struct compat_stat (defined in
arch/x86/include/asm/compat.h) has 16-bit st_dev and st_rdev followed by
a 16-bit padding.

This patch fixes struct compat_stat to match struct stat.

[ Historical note: the old x86 'struct stat' did have that 16-bit field
  that the compat layer had kept around, but it was changes back in 2003
  by "struct stat - support larger dev_t":

    https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=e95b2065677fe32512a597a79db94b77b90c968d



  and back in those days, the x86_64 port was still new, and separate
  from the i386 code, and had already picked up the old version with a
  16-bit st_dev field ]

Note that we can't change compat_dev_t because it is used by
compat_loop_info.

Also, if the st_dev and st_rdev values are 32-bit, we don't have to use
old_valid_dev to test if the value fits into them.  This fixes
-EOVERFLOW on filesystems that are on NVMe because NVMe uses the major
number 259.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      932aba1e
    • Jason A. Donenfeld's avatar
      gcc-plugins: latent_entropy: use /dev/urandom · c40160f2
      Jason A. Donenfeld authored 
      While the latent entropy plugin mostly doesn't derive entropy from
get_random_const() for measuring the call graph, when __latent_entropy is
applied to a constant, then it's initialized statically to output from
get_random_const(). In that case, this data is derived from a 64-bit
seed, which means a buffer of 512 bits doesn't really have that amount
of compile-time entropy.

This patch fixes that shortcoming by just buffering chunks of
/dev/urandom output and doling it out as requested.

At the same time, it's important that we don't break the use of
-frandom-seed, for people who want the runtime benefits of the latent
entropy plugin, while still having compile-time determinism. In that
case, we detect whether gcc's set_random_seed() has been called by
making a call to get_random_seed(noinit=true) in the plugin init
function, which is called after set_random_seed() is called but before
anything that calls get_random_seed(noinit=false), and seeing if it's
zero or not. If it's not zero, we're in deterministic mode, and so we
just generate numbers with a basic xorshift prng.

Note that we don't detect if -frandom-seed is being used using the
documented local_tick variable, because it's assigned via:
   local_tick = (unsigned) tv.tv_sec * 1000 + tv.tv_usec / 1000;
which may well overflow and become -1 on its own, and so isn't
reliable: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105171

[kees: The 256 byte rnd_buf size was chosen based on average (250),
 median (64), and std deviation (575) bytes of used entropy for a
 defconfig x86_64 build]

Fixes: 38addce8

 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220405222815.21155-1-Jason@zx2c4.com
      c40160f2
    • Jakub Kicinski's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf · 625e8cb8
      Jakub Kicinski authored 
      Pablo Neira Ayuso says:

====================
Netfilter fixes for net

1) Fix cgroupv2 from the input path, from Florian Westphal.

2) Fix incorrect return value of nft_parse_register(), from Antoine Tenart.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_tables: nft_parse_register can return a negative value
  netfilter: nft_socket: make cgroup match work in input too
====================

Link: https://lore.kernel.org/r/20220412094246.448055-1-pablo@netfilter.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      625e8cb8
  9. Apr 12, 2022