Guillaume Nault
9afe690185
tcp: fix rejected syncookies due to stale timestamps ...
[ Upstream commit 04d26e7b159a396372646a480f4caa166d1b6720 ]
If no synflood happens for a long enough period of time, then the
synflood timestamp isn't refreshed and jiffies can advance so much
that time_after32() can't accurately compare them any more.
Therefore, we can end up in a situation where time_after32(now,
last_overflow + HZ) returns false, just because these two values are
too far apart. In that case, the synflood timestamp isn't updated as
it should be, which can trick tcp_synq_no_recent_overflow() into
rejecting valid syncookies.
For example, let's consider the following scenario on a system
with HZ=1000:
* The synflood timestamp is 0, either because that's the timestamp
of the last synflood or, more commonly, because we're working with
a freshly created socket.
* We receive a new SYN, which triggers synflood protection. Let's say
that this happens when jiffies == 2147484649 (that is,
'synflood timestamp' + HZ + 2^31 + 1).
* Then tcp_synq_overflow() doesn't update the synflood timestamp,
because time_after32(2147484649, 1000) returns false.
With:
- 2147484649: the value of jiffies, aka. 'now'.
- 1000: the value of 'last_overflow' + HZ.
* A bit later, we receive the ACK completing the 3WHS. But
cookie_v[46]_check() rejects it because tcp_synq_no_recent_overflow()
says that we're not under synflood. That's because
time_after32(2147484649, 120000) returns false.
With:
- 2147484649: the value of jiffies, aka. 'now'.
- 120000: the value of 'last_overflow' + TCP_SYNCOOKIE_VALID.
Of course, in reality jiffies would have increased a bit, but this
condition will last for the next 119 seconds, which is far enough
to accommodate for jiffie's growth.
Fix this by updating the overflow timestamp whenever jiffies isn't
within the [last_overflow, last_overflow + HZ] range. That shouldn't
have any performance impact since the update still happens at most once
per second.
Now we're guaranteed to have fresh timestamps while under synflood, so
tcp_synq_no_recent_overflow() can safely use it with time_after32() in
such situations.
Stale timestamps can still make tcp_synq_no_recent_overflow() return
the wrong verdict when not under synflood. This will be handled in the
next patch.
For 64 bits architectures, the problem was introduced with the
conversion of ->tw_ts_recent_stamp to 32 bits integer by commit
cca9bab1b7cca9bab1b71da177e4c3
2019-12-18 16:08:43 +01:00
can: af_can: export can_sock_destruct()
2019-11-13 10:42:33 +01:00
libceph: add function that clears osd client's abort_err
2019-09-16 12:06:23 +02:00
clk: add include guard to clk-conf.h
2019-09-17 10:27:46 -07:00
net: dsa: sja1105: Fix sleeping while atomic in .port_hwtstamp_set
2019-10-02 12:19:53 -04:00
Char/Misc driver patches for 5.4-rc1
2019-09-18 11:14:31 -07:00
gpiolib: Initialize the hardware with a callback
2019-10-15 01:18:46 +02:00
chrome platform changes for v5.4
2019-09-19 14:14:28 -07:00
Merge branch 'next' into for-linus
2019-09-16 09:56:27 -07:00
mailbox: mediatek: cmdq: clear the event in cmdq initial flow
2019-09-17 00:40:05 -05:00
mfd: rk808: Fix RK818 ID template
2019-12-17 19:56:49 +01:00
net/mlx5: Fix flow counter list auto bits struct
2019-10-29 16:27:17 -07:00
dma-mapping updates for 5.4:
2019-09-19 13:27:23 -07:00
This pull-request contains the following changes for MTD:
2019-09-21 10:59:54 -07:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
dmaengine: imx-sdma: fix size check for sdma script_number
2019-10-14 13:33:44 +05:30
RDMA subsystem updates for 5.4
2019-09-21 10:26:24 -07:00
exit/exec: Seperate mm_release()
2019-11-29 10:10:10 +01:00
drm main pull for 5.4-rc1
2019-09-19 16:24:24 -07:00
soundwire: stream: make stream name a const pointer
2019-09-04 14:57:28 +05:30
SUNRPC: Destroy the back channel when we destroy the host transport
2019-10-30 12:04:35 -04:00
USB changes for 5.4-rc1
2019-09-18 10:33:46 -07:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
bitmap.h: fix kernel-doc warning and typo
2019-10-14 15:04:01 -07:00
lib: introduce copy_struct_from_user() helper
2019-10-01 15:45:03 +02:00
block: Delay default elevator initialization
2019-09-05 19:52:34 -06:00
for-5.4/post-2019-09-24
2019-09-24 16:31:50 -07:00
bpf: Change size to u64 for bpf_map_{area_alloc, charge_init}()
2019-10-31 21:41:33 +01:00
kprobes: Prohibit probing on BUG() and WARN() address
2019-09-05 10:15:16 +02:00
Merge branches 'clk-init-destroy', 'clk-doc', 'clk-imx' and 'clk-allwinner' into clk-next
2019-09-19 15:31:27 -07:00
We have a small collection of core framework updates this time, mostly around
2019-09-20 15:45:07 -07:00
mm, compaction: raise compaction priority after it withdrawns
2019-09-24 15:54:10 -07:00
futex: Move futex exit handling into futex code
2019-11-29 10:10:08 +01:00
include/linux/compiler.h: fix Oops for Clang-compiled kernels
2019-09-08 14:53:58 +02:00
compiler_attributes.h: Add 'fallthrough' pseudo keyword for switch/case use
2019-10-11 09:26:05 -07:00
Make use of gcc 9's "asm inline()" (Rasmus Villemoes):
2019-09-21 09:47:19 -07:00
driver-core: add include guard to linux/container.h
2019-09-04 13:38:26 +02:00
cpu/speculation: Uninline and export CPU mitigations helpers
2019-11-04 12:22:02 +01:00
cpufreq: Use per-policy frequency QoS
2019-10-21 02:05:21 +02:00
Power management updates for 5.4-rc1
2019-09-17 19:15:14 -07:00
cpumask: nicer for_each_cpumask_and() signature
2019-09-25 17:51:40 -07:00
selinux/stable-5.4 PR 20190917
2019-09-23 11:21:04 -07:00
USB changes for 5.4-rc1
2019-09-18 10:33:46 -07:00
dma-mapping updates for 5.4:
2019-09-19 13:27:23 -07:00
dynamic_debug: provide dynamic_hex_dump stub
2019-10-22 12:54:44 -07:00
x86, efi: Never relocate kernel below lowest acceptable address
2019-10-31 09:40:19 +01:00
block: Introduce elevator features
2019-09-05 19:52:33 -06:00
symbol namespaces: revert to previous __ksymtab name scheme
2019-10-18 15:32:52 +02:00
bpf: Fix use after free in subprog's jited symbol removal
2019-10-22 11:26:09 -07:00
compat_ioctl: add compat_ptr_ioctl()
2019-12-17 19:55:30 +01:00
fuse update for 5.4
2019-09-25 09:55:59 -07:00
futex: Add mutex around futex exit
2019-11-29 10:10:13 +01:00
net: fix sk_page_frag() recursion from memory reclaim
2019-10-28 16:17:31 -07:00
Linux 5.3-rc7
2019-09-05 11:40:54 +02:00
HID: core: Add printk_once variants to hid_warn() etc
2019-09-18 15:58:13 +02:00
libnvdimm fixes v5.4-rc1
2019-09-29 10:33:41 -07:00
mm: introduce page_size()
2019-09-24 15:54:08 -07:00
hwmon: Fix HWMON_P_MIN_ALARM mask
2019-10-02 06:36:50 -07:00
- First round of vmbus hibernation support from Dexuan Cui.
2019-09-24 12:36:31 -07:00
Merge branch 'i2c/for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
2019-09-24 16:48:02 -07:00
XArray updates for 5.4
2019-11-08 08:46:49 -08:00
net: remove unnecessary variables and callback
2019-10-24 14:53:49 -07:00
team: fix nested locking lockdep warning
2019-10-24 14:53:48 -07:00
net: remove unnecessary variables and callback
2019-10-24 14:53:49 -07:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
iommu/vt-d: Fix QI_DEV_IOTLB_PFSID and QI_DEV_EIOTLB_PFSID macros
2019-11-11 16:10:54 +01:00
Power management updates for 5.4-rc1
2019-09-17 19:15:14 -07:00
augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro
2019-09-25 17:51:39 -07:00
iomap: move the iomap_dio_rw ->end_io callback into a structure
2019-09-19 15:32:45 -07:00
jbd2: Fix possible overflow in jbd2_log_space_left()
2019-12-13 08:42:53 +01:00
kernel.h: Add non_block_start/end()
2019-09-07 04:28:05 -03:00
kernfs: fix ino wrap-around detection
2019-12-13 08:42:53 +01:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
kgdb: don't use a notifier to enter kgdb at panic; call directly
2019-09-25 17:51:40 -07:00
khugepaged: enable collapse pmd for pte-mapped THP
2019-09-24 15:54:11 -07:00
Bugfixes: unwinding of KVM_CREATE_VM failure,
2019-11-12 13:19:15 -08:00
leds: core: Fix leds.h structure documentation
2019-10-08 22:05:58 +02:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
include: mdio: Add driver data helpers
2019-09-05 12:32:05 +02:00
mm, memcg: make scan aggression always exclude protection
2019-10-07 15:47:20 -07:00
mm/memory_hotplug: fix try_offline_node()
2019-11-15 18:34:00 -08:00
Revert "Revert "mm, thp: restore node-local hugepage allocations""
2019-09-28 14:05:38 -07:00
libnvdimm fixes v5.4-rc1
2019-09-29 10:33:41 -07:00
net: phy: micrel: Update KSZ87xx PHY name
2019-10-17 16:31:52 -07:00
net: phy: fix write to mii-ctrl1000 register
2019-10-04 18:11:08 -07:00
rfkill: allocate static minor
2019-12-13 08:43:18 +01:00
mm: thp: handle page cache THP correctly in PageTransCompoundMap
2019-11-06 08:28:58 -08:00
mm: thp: handle page cache THP correctly in PageTransCompoundMap
2019-11-06 08:28:58 -08:00
fork: improve error message for corrupted page tables
2019-09-25 17:51:40 -07:00
mm/mmu_notifiers: annotate with might_sleep()
2019-09-07 04:28:04 -03:00
mm: thp: extract split_queue_* into a struct
2019-09-24 15:54:11 -07:00
Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
2019-09-27 19:37:27 -07:00
inet: protect against too small mtu values.
2019-12-18 16:08:17 +01:00
netfilter: remove CONFIG_NETFILTER checks from headers.
2019-09-13 12:47:36 +02:00
netfilter: move nf_bridge_frag_data struct definition to a more appropriate header.
2019-09-13 12:35:33 +02:00
netfilter: move nf_bridge_frag_data struct definition to a more appropriate header.
2019-09-13 12:35:33 +02:00
NFS: Refactor nfs_instantiate() for dentry referencing callers
2019-09-20 15:15:24 -04:00
gpio: of: Make of_gpio_simple_xlate() private
2019-09-11 14:46:02 +01:00
padata: remove cpu_index from the parallel_queue
2019-09-13 21:15:41 +10:00
mm: thp: handle page cache THP correctly in PageTransCompoundMap
2019-11-06 08:28:58 -08:00
mm, page_owner: rename flag indicating that page is allocated
2019-10-14 15:04:00 -07:00
mm: page cache: store only head pages in i_pages
2019-09-24 15:54:08 -07:00
pagewalk: separate function pointers from iterator data
2019-09-07 04:28:04 -03:00
pci-v5.4-changes
2019-09-23 19:16:01 -07:00
pci-v5.4-changes
2019-09-23 19:16:01 -07:00
perf/headers: Fix spelling s/EACCESS/EACCES/, s/privilidge/privilege/
2019-10-28 11:02:01 +01:00
net: phy: extract pause mode
2019-10-04 18:11:08 -07:00
net: fixed_phy: Add forward declaration for struct gpio_desc;
2019-09-05 11:54:14 +02:00
driver core: platform: Add platform_get_irq_byname_optional()
2019-10-07 12:52:44 +02:00
PM: QoS: Drop frequency QoS types from device PM QoS
2019-10-21 02:05:21 +02:00
posix-cpu-timers: Always clear head pointer on dequeue
2019-09-05 21:16:22 +02:00
lib/hexdump: make print_hex_dump_bytes() a nop on !DEBUG builds
2019-09-25 17:51:39 -07:00
pwm: Ensure pwm_apply_state() doesn't modify the state argument
2019-09-21 03:25:10 +02:00
quota: Check that quota is not dirty before release
2019-12-17 19:56:43 +01:00
radix tree: Remove radix_tree_iter_find
2019-11-01 22:26:34 -04:00
vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
2019-09-12 21:05:34 -04:00
augmented rbtree: rework the RB_DECLARE_CALLBACKS macro definition
2019-09-25 17:51:39 -07:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-16 17:25:49 -07:00
tasks, sched/core: With a grace period after finish_task_switch(), remove unnecessary code
2019-09-25 17:42:29 +02:00
reset: fix reset_control_ops kerneldoc comment
2019-10-28 12:18:23 +01:00
reset: fix reset_control_get_exclusive kerneldoc comment
2019-10-24 10:26:33 +02:00
cifs: Add support for root file systems
2019-09-16 11:43:38 -05:00
futex: Add mutex around futex exit
2019-11-29 10:10:13 +01:00
efi/efi_test: Lock down /dev/efi_test and require CAP_SYS_ADMIN
2019-10-31 09:40:21 +01:00
vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
2019-09-12 21:05:34 -04:00
mm: shrinker: make shrinker not depend on memcg kmem
2019-09-24 15:54:11 -07:00
udp: drop skb extensions before marking skb stateless
2019-11-22 09:28:46 -08:00
net: skmsg: fix TLS 1.3 crash with full sk_msg
2019-12-04 22:31:01 +01:00
mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
2019-10-07 15:47:20 -07:00
net: increase SOMAXCONN to 4096
2019-10-31 14:01:40 -07:00
net: stmmac: implement support for passive mode converters via dt
2019-09-11 15:27:09 +01:00
lib/string: Make memzero_explicit() inline instead of external
2019-10-08 13:27:05 +02:00
mm: introduce MADV_PAGEOUT
2019-09-25 17:51:41 -07:00
swiotlb: Split size parameter to map/unmap APIs
2019-09-11 12:34:29 +02:00
ipc: fix sparc64 ipc() wrapper
2019-09-07 21:42:25 +02:00
sysfs: Fixes __BIN_ATTR_WO() macro
2019-10-02 10:06:45 +02:00
block: centralize PI remapping logic to the block layer
2019-09-17 20:03:49 -06:00
tcp: add rcu protection around tp->fastopen_rsk
2019-10-13 10:13:08 -07:00
uaccess: add missing __must_check attributes
2019-09-25 17:51:40 -07:00
tcp: fix rejected syncookies due to stale timestamps
2019-12-18 16:08:43 +01:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-16 17:25:49 -07:00
efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing
2019-10-07 15:24:36 +02:00
uaccess: implement a proper unsafe_copy_to_user() and switch filldir over to it
2019-10-07 12:56:48 -07:00
vsock/virtio: remove unused 'work' field from 'struct virtio_vsock_pkt'
2019-10-28 04:25:04 -04:00
mm/vmalloc: modify struct vmap_area to reduce its size
2019-09-24 15:54:10 -07:00
w1: add 1-wire master driver for IP block found in SGI ASICs
2019-09-04 14:34:31 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-17 12:35:15 -07:00
workqueue: unconfine alloc/apply/free_workqueue_attrs()
2019-09-13 21:15:39 +10:00
xarray.h: fix kernel-doc warning
2019-10-14 15:04:01 -07:00
zpool: add malloc_support_movable to zpool_driver
2019-09-24 15:54:12 -07:00
