Daniel Borkmann
de8f3a83b0
bpf: add meta pointer for direct access ...
This work enables generic transfer of metadata from XDP into skb. The
basic idea is that we can make use of the fact that the resulting skb
must be linear and already comes with a larger headroom for supporting
bpf_xdp_adjust_head(), which mangles xdp->data. Here, we base our work
on a similar principle and introduce a small helper bpf_xdp_adjust_meta()
for adjusting a new pointer called xdp->data_meta. Thus, the packet has
a flexible and programmable room for meta data, followed by the actual
packet data. struct xdp_buff is therefore laid out that we first point
to data_hard_start, then data_meta directly prepended to data followed
by data_end marking the end of packet. bpf_xdp_adjust_head() takes into
account whether we have meta data already prepended and if so, memmove()s
this along with the given offset provided there's enough room.
xdp->data_meta is optional and programs are not required to use it. The
rationale is that when we process the packet in XDP (e.g. as DoS filter),
we can push further meta data along with it for the XDP_PASS case, and
give the guarantee that a clsact ingress BPF program on the same device
can pick this up for further post-processing. Since we work with skb
there, we can also set skb->mark, skb->priority or other skb meta data
out of BPF, thus having this scratch space generic and programmable
allows for more flexibility than defining a direct 1:1 transfer of
potentially new XDP members into skb (it's also more efficient as we
don't need to initialize/handle each of such new members). The facility
also works together with GRO aggregation. The scratch space at the head
of the packet can be multiple of 4 byte up to 32 byte large. Drivers not
yet supporting xdp->data_meta can simply be set up with xdp->data_meta
as xdp->data + 1 as bpf_xdp_adjust_meta() will detect this and bail out,
such that the subsequent match against xdp->data for later access is
guaranteed to fail.
The verifier treats xdp->data_meta/xdp->data the same way as we treat
xdp->data/xdp->data_end pointer comparisons. The requirement for doing
the compare against xdp->data is that it hasn't been modified from it's
original address we got from ctx access. It may have a range marking
already from prior successful xdp->data/xdp->data_end pointer comparisons
though.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-26 13:36:44 -07:00
bpf: add meta pointer for direct access
2017-09-26 13:36:44 -07:00
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-09-12 11:30:56 -07:00
ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES.
2017-08-22 18:43:23 -07:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
2017-03-02 08:42:34 +01:00
bpf: one perf event close won't free bpf program attached by another perf event
2017-09-20 14:10:29 -07:00
gcov: support GCC 7.1
2017-05-12 15:57:15 -07:00
genirq: Fix cpumask check in __irq_startup_managed()
2017-09-16 20:20:56 +02:00
livepatch: Fix stacking of patches with respect to RCU
2017-06-20 10:42:19 +02:00
mm: treewide: remove GFP_TEMPORARY allocation flag
2017-09-13 18:53:16 -07:00
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-09-12 11:30:56 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
2017-09-07 21:00:52 -07:00
treewide: make "nr_cpu_ids" unsigned
2017-09-08 18:26:48 -07:00
sched/wait: Introduce wakeup boomark in wake_up_page_bit
2017-09-14 09:56:18 -07:00
drivers/pps: aesthetic tweaks to PPS-related content
2017-09-08 18:26:51 -07:00
This includes 3 minor fixes.
2017-09-20 06:38:07 -10:00
fs: make the buf argument to __kernel_write a void pointer
2017-09-04 19:05:15 -04:00
async: Adjust system_state checks
2017-05-23 10:01:37 +02:00
audit: update the function comments
2017-09-05 09:46:59 -04:00
ipc: mqueue: Replace timespec with timespec64
2017-09-03 20:21:24 -04:00
Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
2017-05-03 11:05:15 -07:00
Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
2017-05-03 11:05:15 -07:00
audit/stable-4.13 PR 20170816
2017-08-16 16:48:34 -07:00
audit: kernel generated netlink traffic should have a portid of 0
2017-05-02 10:16:05 -04:00
Merge branch 'work.ipc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-09-14 17:37:26 -07:00
semtimedop(): move compat to native
2017-07-15 20:46:47 -04:00
Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-09-04 13:53:53 -07:00
PM / CPU: replace raw_notifier with atomic_notifier
2017-07-31 13:09:49 +02:00
kdump: protect vmcoreinfo data under the crash memory
2017-07-12 16:26:00 -07:00
doc: ReSTify credentials.txt
2017-05-18 10:30:19 -06:00
sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>
2017-03-02 08:42:39 +01:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2017-09-11 18:34:47 -07:00
lib/extable.c: use bsearch() library function in search_extable()
2017-07-10 16:32:35 -07:00
selinux/stable-4.14 PR 20170831
2017-09-12 13:21:00 -07:00
futex: Remove duplicated code and fix undefined behaviour
2017-08-25 22:49:59 +02:00
kernel/groups.c: use sort library function
2017-07-10 16:32:34 -07:00
kernel/hung_task.c: defer showing held locks
2017-05-08 17:15:10 -07:00
jump_label: Provide hotplug context variants
2017-08-10 12:28:59 +02:00
kernel/kallsyms.c: replace all_var with IS_ENABLED(CONFIG_KALLSYMS_ALL)
2017-07-10 16:32:34 -07:00
kcmp: add KCMP_EPOLL_TFD mode to compare epoll target files
2017-07-12 16:26:01 -07:00
kcov: support compat processes
2017-09-08 18:26:51 -07:00
kdump: protect vmcoreinfo data under the crash memory
2017-07-12 16:26:00 -07:00
x86/mm, kexec: Allow kexec to be used with SME
2017-07-18 11:38:04 +02:00
kexec_file: adjust declaration of kexec_purgatory
2017-07-12 16:26:02 -07:00
kexec_file: adjust declaration of kexec_purgatory
2017-07-12 16:26:02 -07:00
kmod: move #ifdef CONFIG_MODULES wrapper to Makefile
2017-09-08 18:26:51 -07:00
kprobes: Ensure that jprobe probepoints are at function entry
2017-07-08 11:05:35 +02:00
kexec: move vmcoreinfo out of the kernel's .bss section
2017-07-12 16:25:59 -07:00
kernel/kthread.c: kthread_worker: don't hog the cpu
2017-08-31 16:33:15 -07:00
sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>
2017-03-02 08:42:39 +01:00
kmod: move #ifdef CONFIG_MODULES wrapper to Makefile
2017-09-08 18:26:51 -07:00
mm/device-public-memory: device memory cache coherent with CPU
2017-09-08 18:26:46 -07:00
module: fix ddebug_remove_module()
2017-07-25 15:08:32 +02:00
kernel/notifier.c: simplify expression
2017-02-24 17:46:56 -08:00
perf: Add PERF_RECORD_NAMESPACES to include namespaces related info
2017-03-13 15:57:41 -03:00
padata: Avoid nested calls to cpus_read_lock() in pcrypt_init_padata()
2017-05-26 10:10:37 +02:00
locking/refcounts, x86/asm: Implement fast refcount overflow protection
2017-08-17 10:40:26 +02:00
boot/param: Move next_arg() function to lib/cmdline.c for later reuse
2017-04-18 10:37:13 +02:00
pids: make task_tgid_nr_ns() safe
2017-08-21 12:47:31 -07:00
userns,pidns: Verify the userns for new pid namespaces
2017-07-20 07:43:58 -05:00
sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>
2017-03-02 08:42:39 +01:00
signal: Remove kernel interal si_code magic
2017-07-24 14:30:28 -05:00
Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-02 11:38:06 -07:00
seccomp: Implement SECCOMP_RET_KILL_PROCESS action
2017-08-14 13:46:50 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2017-09-11 18:34:47 -07:00
treewide: make "nr_cpu_ids" unsigned
2017-09-08 18:26:48 -07:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
2017-03-02 08:42:35 +01:00
sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags()
2017-04-11 09:06:32 +02:00
stacktrace/x86: add function for detecting reliable stack traces
2017-03-08 09:18:02 +01:00
stop_machine: Provide stop_machine_cpuslocked()
2017-05-26 10:10:36 +02:00
prctl: Allow local CAP_SYS_ADMIN changing exe_file
2017-07-20 07:46:07 -05:00
kernel/watchdog: split up config options
2017-07-12 16:26:02 -07:00
fs: fix kernel_write prototype
2017-09-04 19:05:15 -04:00
task_work: Replace spin_unlock_wait() with lock/unlock pair
2017-07-25 10:08:58 -07:00
taskstats: add e/u/stime for TGID command
2017-05-08 17:15:12 -07:00
torture: Fix typo suppressing CPU-hotplug statistics
2017-07-25 13:04:45 -07:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
2017-03-02 08:42:35 +01:00
sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>
2017-03-02 08:42:39 +01:00
ucount: Remove the atomicity from ucount->count
2017-03-06 15:26:37 -06:00
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
2017-03-02 08:42:31 +01:00
kmod: split out umh code into its own file
2017-09-08 18:26:50 -07:00
smp: Avoid using two cache lines for struct call_single_data
2017-08-29 15:14:38 +02:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>
2017-03-02 08:42:29 +01:00
userns,pidns: Verify the userns for new pid namespaces
2017-07-20 07:43:58 -05:00
sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>
2017-03-02 08:42:38 +01:00
sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
2017-03-03 01:45:36 +01:00
kernel/watchdog: Prevent false positives with turbo modes
2017-08-18 12:35:02 +02:00
kernel/watchdog: Prevent false positives with turbo modes
2017-08-18 12:35:02 +02:00
Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2017-09-06 21:59:31 -07:00
de8f3a83b0