Daniel Borkmann says:
====================
pull-request: bpf-next 2023-11-21
We've added 85 non-merge commits during the last 12 day(s) which contain
a total of 63 files changed, 4464 insertions(+), 1484 deletions(-).
The main changes are:
1) Huge batch of verifier changes to improve BPF register bounds logic
and range support along with a large test suite, and verifier log
improvements, all from Andrii Nakryiko.
2) Add a new kfunc which acquires the associated cgroup of a task within
a specific cgroup v1 hierarchy where the latter is identified by its id,
from Yafang Shao.
3) Extend verifier to allow bpf_refcount_acquire() of a map value field
obtained via direct load which is a use-case needed in sched_ext,
from Dave Marchevsky.
4) Fix bpf_get_task_stack() helper to add the correct crosstask check
for the get_perf_callchain(), from Jordan Rome.
5) Fix BPF task_iter internals where lockless usage of next_thread()
was wrong. The rework also simplifies the code, from Oleg Nesterov.
6) Fix uninitialized tail padding via LIBBPF_OPTS_RESET, and another
fix for certain BPF UAPI structs to fix verifier failures seen
in bpf_dynptr usage, from Yonghong Song.
7) Add BPF selftest fixes for map_percpu_stats flakes due to per-CPU BPF
memory allocator not being able to allocate per-CPU pointer successfully,
from Hou Tao.
8) Add prep work around dynptr and string handling for kfuncs which
is later going to be used by file verification via BPF LSM and fsverity,
from Song Liu.
9) Improve BPF selftests to update multiple prog_tests to use ASSERT_*
macros, from Yuran Pereira.
10) Optimize LPM trie lookup to check prefixlen before walking the trie,
from Florian Lehner.
11) Consolidate virtio/9p configs from BPF selftests in config.vm file
given they are needed consistently across archs, from Manu Bretelle.
12) Small BPF verifier refactor to remove register_is_const(),
from Shung-Hsi Yu.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (85 commits)
selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in vmlinux
selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bpf_obj_id
selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bind_perm
selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bpf_tcp_ca
selftests/bpf: reduce verboseness of reg_bounds selftest logs
bpf: bpf_iter_task_next: use next_task(kit->task) rather than next_task(kit->pos)
bpf: bpf_iter_task_next: use __next_thread() rather than next_thread()
bpf: task_group_seq_get_next: use __next_thread() rather than next_thread()
bpf: emit frameno for PTR_TO_STACK regs if it differs from current one
bpf: smarter verifier log number printing logic
bpf: omit default off=0 and imm=0 in register state log
bpf: emit map name in register state if applicable and available
bpf: print spilled register state in stack slot
bpf: extract register state printing
bpf: move verifier state printing code to kernel/bpf/log.c
bpf: move verbose_linfo() into kernel/bpf/log.c
bpf: rename BPF_F_TEST_SANITY_STRICT to BPF_F_TEST_REG_INVARIANTS
bpf: Remove test for MOVSX32 with offset=32
selftests/bpf: add iter test requiring range x range logic
veristat: add ability to set BPF_F_TEST_SANITY_STRICT flag with -r flag
...
====================
Link: https://lore.kernel.org/r/20231122000500.28126-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In the spirit of failing early, timeout on unbounded loops that take
longer than 20 ticks to complete. Such loops are to ensure that objects
created are already visible so tests can proceed without any issues.
If a test setup takes more than 20 ticks to see an object, there's
definetely something wrong.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20231117171208.2066136-6-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We have observed a lot of lock contention and test instability when running with >8 cores.
Enough to actually make the tests run slower than with fewer cores.
Cap the maximum cores of parallel tdc to 4 which showed in testing to
be a reasonable number for efficiency and stability in different kernel
config scenarios.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20231117171208.2066136-2-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 29f834aa32 ("net_sched: sch_fq: add 3 bands and WRR
scheduling") introduces multiple traffic bands, and per-band maximum
packet count.
Per-band limits ensures that packets in one class cannot fill the
entire qdisc and so cause DoS to the traffic in the other classes.
Verify this behavior:
1. set the limit to 10 per band
2. send 20 pkts on band A: verify that 10 are queued, 10 dropped
3. send 20 pkts on band A: verify that 0 are queued, 20 dropped
4. send 20 pkts on band B: verify that 10 are queued, 10 dropped
Packets must remain queued for a period to trigger this behavior.
Use SO_TXTIME to store packets for 100 msec.
The test reuses existing upstream test infra. The script is a fork of
cmsg_time.sh. The scripts call cmsg_sender.
The test extends cmsg_sender with two arguments:
* '-P' SO_PRIORITY
There is a subtle difference between IPv4 and IPv6 stack behavior:
PF_INET/IP_TOS sets IP header bits and sk_priority
PF_INET6/IPV6_TCLASS sets IP header bits BUT NOT sk_priority
* '-n' num pkts
Send multiple packets in quick succession.
I first attempted a for loop in the script, but this is too slow in
virtualized environments, causing flakiness as the 100ms timeout is
reached and packets are dequeued.
Also do not wait for timestamps to be queued unless timestamps are
requested.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20231116203449.2627525-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reduce verboseness of test_progs' output in reg_bounds set of tests with
two changes.
First, instead of each different operator (<, <=, >, ...) being it's own
subtest, combine all different ops for the same (x, y, init_t, cond_t)
values into single subtest. Instead of getting 6 subtests, we get one
generic one, e.g.:
#192/53 reg_bounds_crafted/(s64)[0xffffffffffffffff; 0] (s64)<op> 0xffffffff00000000:OK
Second, for random generated test cases, treat all of them as a single
test to eliminate very verbose output with random values in them. So now
we'll just get one line per each combination of (init_t, cond_t),
instead of 6 x 25 = 150 subtests before this change:
#225 reg_bounds_rand_consts_s32_s32:OK
Given we reduce verboseness so much, it makes sense to do a bit more
random testing, so we also bump default number of random tests to 100,
up from 25. This doesn't increase runtime significantly, especially in
parallelized mode.
With all the above changes we still make sure that we have all the
information necessary for reproducing test case if it happens to fail.
That includes reporting random seed and specific operator that is
failing. Those will only be printed to console if related test/subtest
fails, so it doesn't have any added verboseness implications.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231120180452.145849-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of always printing numbers as either decimals (and in some
cases, like for "imm=%llx", in hexadecimals), decide the form based on
actual values. For numbers in a reasonably small range (currently,
[0, U16_MAX] for unsigned values, and [S16_MIN, S16_MAX] for signed ones),
emit them as decimals. In all other cases, even for signed values,
emit them in hexadecimals.
For large values hex form is often times way more useful: it's easier to
see an exact difference between 0xffffffff80000000 and 0xffffffff7fffffff,
than between 18446744071562067966 and 18446744071562067967, as one
particular example.
Small values representing small pointer offsets or application
constants, on the other hand, are way more useful to be represented in
decimal notation.
Adjust reg_bounds register state parsing logic to take into account this
change.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231118034623.3320920-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Simplify BPF verifier log further by omitting default (and frequently
irrelevant) off=0 and imm=0 parts for non-SCALAR_VALUE registers. As can
be seen from fixed tests, this is often a visual noise for PTR_TO_CTX
register and even for PTR_TO_PACKET registers.
Omitting default values follows the rest of register state logic: we
omit default values to keep verifier log succinct and to highlight
interesting state that deviates from default one. E.g., we do the same
for var_off, when it's unknown, which gives no additional information.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231118034623.3320920-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In complicated real-world applications, whenever debugging some
verification error through verifier log, it often would be very useful
to see map name for PTR_TO_MAP_VALUE register. Usually this needs to be
inferred from key/value sizes and maybe trying to guess C code location,
but it's not always clear.
Given verifier has the name, and it's never too long, let's just emit it
for ptr_to_map_key, ptr_to_map_value, and const_ptr_to_map registers. We
reshuffle the order a bit, so that map name, key size, and value size
appear before offset and immediate values, which seems like a more
logical order.
Current output:
R1_w=map_ptr(map=array_map,ks=4,vs=8,off=0,imm=0)
But we'll get rid of useless off=0 and imm=0 parts in the next patch.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231118034623.3320920-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Test that PCI reset works correctly by verifying that only the expected
reset methods are supported and that after issuing the reset the ifindex
of the port changes.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sockets used by udpgso_bench_tx aren't always ready when
udpgso_bench_tx transmits packets. This issue is more prevalent in -rt
kernels, but can occur in both. Replace the hacky sleep calls with a
function that checks whether the ports in the namespace are ready for
use.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Lucas Karpinski <lkarpins@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Leverage parallel tests in kselftests using all the available cpus.
We tested this in tuxsuite and locally extensively and it seems it's ready for prime time.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
While running tdc tests in parallel it can race over the module loading
done by tc and fail the run with random errors.
So avoid this by preloading all modules before running tdc in kselftests.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As mentioned in the TC Workshop 0x17, our recent changes to tdc broke
downstream CI systems like tuxsuite. The issue is the classic problem
with rcu/workqueue objects where you can miss them if not enough wall time
has passed. The latter is subjective to the system and kernel config,
in my machine could be nanoseconds while in another could be microseconds
or more.
In order to make the suite deterministic, poll for the existence
of the objects in a reasonable manner. Talking netlink directly is the
the best solution in order to avoid paying the cost of multiple
'fork()' calls, so introduce a netlink based setup routine using
pyroute2. We leave the iproute2 one as a fallback when pyroute2 is not
available.
Also rework the iproute2 side to mimic the netlink routine where it
creates DEV0 as the peer of DEV1 and moves DEV1 into the net namespace.
This way when the namespace is deleted DEV0 is also deleted
automatically, leaving no margin for resource leaks.
Another bonus of this change is that our setup time sped up by a factor
of 2 when using netlink.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This argument would bypass the net namespace creation and run the test in
the root namespace, even if nsPlugin was specified.
Drop it as it's the same as commenting out the nsPlugin from a test and adds
additional complexity to the plugin code.
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from Paolo Abeni:
"Including fixes from BPF and netfilter.
Current release - regressions:
- core: fix undefined behavior in netdev name allocation
- bpf: do not allocate percpu memory at init stage
- netfilter: nf_tables: split async and sync catchall in two
functions
- mptcp: fix possible NULL pointer dereference on close
Current release - new code bugs:
- eth: ice: dpll: fix initial lock status of dpll
Previous releases - regressions:
- bpf: fix precision backtracking instruction iteration
- af_unix: fix use-after-free in unix_stream_read_actor()
- tipc: fix kernel-infoleak due to uninitialized TLV value
- eth: bonding: stop the device in bond_setup_by_slave()
- eth: mlx5:
- fix double free of encap_header
- avoid referencing skb after free-ing in drop path
- eth: hns3: fix VF reset
- eth: mvneta: fix calls to page_pool_get_stats
Previous releases - always broken:
- core: set SOCK_RCU_FREE before inserting socket into hashtable
- bpf: fix control-flow graph checking in privileged mode
- eth: ppp: limit MRU to 64K
- eth: stmmac: avoid rx queue overrun
- eth: icssg-prueth: fix error cleanup on failing initialization
- eth: hns3: fix out-of-bounds access may occur when coalesce info is
read via debugfs
- eth: cortina: handle large frames
Misc:
- selftests: gso: support CONFIG_MAX_SKB_FRAGS up to 45"
* tag 'net-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (78 commits)
macvlan: Don't propagate promisc change to lower dev in passthru
net: sched: do not offload flows with a helper in act_ct
net/mlx5e: Check return value of snprintf writing to fw_version buffer for representors
net/mlx5e: Check return value of snprintf writing to fw_version buffer
net/mlx5e: Reduce the size of icosq_str
net/mlx5: Increase size of irq name buffer
net/mlx5e: Update doorbell for port timestamping CQ before the software counter
net/mlx5e: Track xmit submission to PTP WQ after populating metadata map
net/mlx5e: Avoid referencing skb after free-ing in drop path of mlx5e_sq_xmit_wqe
net/mlx5e: Don't modify the peer sent-to-vport rules for IPSec offload
net/mlx5e: Fix pedit endianness
net/mlx5e: fix double free of encap_header in update funcs
net/mlx5e: fix double free of encap_header
net/mlx5: Decouple PHC .adjtime and .adjphase implementations
net/mlx5: DR, Allow old devices to use multi destination FTE
net/mlx5: Free used cpus mask when an IRQ is released
Revert "net/mlx5: DR, Supporting inline WQE when possible"
bpf: Do not allocate percpu memory at init stage
net: Fix undefined behavior in netdev name allocation
dt-bindings: net: ethernet-controller: Fix formatting error
...
Alexei Starovoitov says:
====================
pull-request: bpf 2023-11-15
We've added 7 non-merge commits during the last 6 day(s) which contain
a total of 9 files changed, 200 insertions(+), 49 deletions(-).
The main changes are:
1) Do not allocate bpf specific percpu memory unconditionally, from Yonghong.
2) Fix precision backtracking instruction iteration, from Andrii.
3) Fix control flow graph checking, from Andrii.
4) Fix xskxceiver selftest build, from Anders.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Do not allocate percpu memory at init stage
selftests/bpf: add more test cases for check_cfg()
bpf: fix control-flow graph checking in privileged mode
selftests/bpf: add edge case backtracking logic test
bpf: fix precision backtracking instruction iteration
bpf: handle ldimm64 properly in check_cfg()
selftests: bpf: xskxceiver: ksft_print_msg: fix format type error
====================
Link: https://lore.kernel.org/r/20231115214949.48854-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a simple verifier test that requires deriving reg bounds for one
register from another register that's not a constant. This is
a realistic example of iterating elements of an array with fixed maximum
number of elements, but smaller actual number of elements.
This small example was an original motivation for doing this whole patch
set in the first place, yes.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-14-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new flag -r (--test-sanity), similar to -t (--test-states), to add
extra BPF program flags when loading BPF programs.
This allows to use veristat to easily catch sanity violations in
production BPF programs.
reg_bounds tests are also enforcing BPF_F_TEST_SANITY_STRICT flag now.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-13-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sure to set BPF_F_TEST_SANITY_STRICT program flag by default across
most verifier tests (and a bunch of others that set custom prog flags).
There are currently two tests that do fail validation, if enforced
strictly: verifier_bounds/crossing_64_bit_signed_boundary_2 and
verifier_bounds/crossing_32_bit_signed_boundary_2. To accommodate them,
we teach test_loader a flag negation:
__flag(!<flagname>) will *clear* specified flag, allowing easy opt-out.
We apply __flag(!BPF_F_TEST_SANITY_STRICT) to these to tests.
Also sprinkle BPF_F_TEST_SANITY_STRICT everywhere where we already set
test-only BPF_F_TEST_RND_HI32 flag, for completeness.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-12-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Now that verifier supports range vs range bounds adjustments, validate
that by checking each generated range against every other generated
range, across all supported operators (everything by JSET).
We also add few cases that were problematic during development either
for verifier or for selftest's range tracking implementation.
Note that we utilize the same trick with splitting everything into
multiple independent parallelizable tests, but init_t and cond_t. This
brings down verification time in parallel mode from more than 8 hours
down to less that 1.5 hours. 106 million cases were successfully
validate for range vs range logic, in addition to about 7 million range
vs const cases, added in earlier patch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-10-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add test to validate BPF verifier's register range bounds tracking logic.
The main bulk is a lot of auto-generated tests based on a small set of
seed values for lower and upper 32 bits of full 64-bit values.
Currently we validate only range vs const comparisons, but the idea is
to start validating range over range comparisons in subsequent patch set.
When setting up initial register ranges we treat registers as one of
u64/s64/u32/s32 numeric types, and then independently perform conditional
comparisons based on a potentially different u64/s64/u32/s32 types. This
tests lots of tricky cases of deriving bounds information across
different numeric domains.
Given there are lots of auto-generated cases, we guard them behind
SLOW_TESTS=1 envvar requirement, and skip them altogether otherwise.
With current full set of upper/lower seed value, all supported
comparison operators and all the combinations of u64/s64/u32/s32 number
domains, we get about 7.7 million tests, which run in about 35 minutes
on my local qemu instance without parallelization. But we also split
those tests by init/cond numeric types, which allows to rely on
test_progs's parallelization of tests with `-j` option, getting run time
down to about 5 minutes on 8 cores. It's still something that shouldn't
be run during normal test_progs run. But we can run it a reasonable
time, and so perhaps a nightly CI test run (once we have it) would be
a good option for this.
We also add a small set of tricky conditions that came up during
development and triggered various bugs or corner cases in either
selftest's reimplementation of range bounds logic or in verifier's logic
itself. These are fast enough to be run as part of normal test_progs
test run and are great for a quick sanity checking.
Let's take a look at test output to understand what's going on:
$ sudo ./test_progs -t reg_bounds_crafted
#191/1 reg_bounds_crafted/(u64)[0; 0xffffffff] (u64)< 0:OK
...
#191/115 reg_bounds_crafted/(u64)[0; 0x17fffffff] (s32)< 0:OK
...
#191/137 reg_bounds_crafted/(u64)[0xffffffff; 0x100000000] (u64)== 0:OK
Each test case is uniquely and fully described by this generated string.
E.g.: "(u64)[0; 0x17fffffff] (s32)< 0". This means that we
initialize a register (R6) in such a way that verifier knows that it can
have a value in [(u64)0; (u64)0x17fffffff] range. Another
register (R7) is also set up as u64, but this time a constant (zero in
this case). They then are compared using 32-bit signed < operation.
Resulting TRUE/FALSE branches are evaluated (including cases where it's
known that one of the branches will never be taken, in which case we
validate that verifier also determines this as a dead code). Test
validates that verifier's final register state matches expected state
based on selftest's own reg_state logic, implemented from scratch for
cross-checking purposes.
These test names can be conveniently used for further debugging, and if -vv
verboseness is requested we can get a corresponding verifier log (with
mark_precise logs filtered out as irrelevant and distracting). Example below is
slightly redacted for brevity, omitting irrelevant register output in
some places, marked with [...].
$ sudo ./test_progs -a 'reg_bounds_crafted/(u32)[0; U32_MAX] (s32)< -1' -vv
...
VERIFIER LOG:
========================
func#0 @0
0: R1=ctx(off=0,imm=0) R10=fp0
0: (05) goto pc+2
3: (85) call bpf_get_current_pid_tgid#14 ; R0_w=scalar()
4: (bc) w6 = w0 ; R0_w=scalar() R6_w=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
5: (85) call bpf_get_current_pid_tgid#14 ; R0_w=scalar()
6: (bc) w7 = w0 ; R0_w=scalar() R7_w=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
7: (b4) w1 = 0 ; R1_w=0
8: (b4) w2 = -1 ; R2=4294967295
9: (ae) if w6 < w1 goto pc-9
9: R1=0 R6=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
10: (2e) if w6 > w2 goto pc-10
10: R2=4294967295 R6=scalar(smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
11: (b4) w1 = -1 ; R1_w=4294967295
12: (b4) w2 = -1 ; R2_w=4294967295
13: (ae) if w7 < w1 goto pc-13 ; R1_w=4294967295 R7=4294967295
14: (2e) if w7 > w2 goto pc-14
14: R2_w=4294967295 R7=4294967295
15: (bc) w0 = w6 ; [...] R6=scalar(id=1,smin=0,smax=umax=4294967295,var_off=(0x0; 0xffffffff))
16: (bc) w0 = w7 ; [...] R7=4294967295
17: (ce) if w6 s< w7 goto pc+3 ; R6=scalar(id=1,smin=0,smax=umax=4294967295,smin32=-1,var_off=(0x0; 0xffffffff)) R7=4294967295
18: (bc) w0 = w6 ; [...] R6=scalar(id=1,smin=0,smax=umax=4294967295,smin32=-1,var_off=(0x0; 0xffffffff))
19: (bc) w0 = w7 ; [...] R7=4294967295
20: (95) exit
from 17 to 21: [...]
21: (bc) w0 = w6 ; [...] R6=scalar(id=1,smin=umin=umin32=2147483648,smax=umax=umax32=4294967294,smax32=-2,var_off=(0x80000000; 0x7fffffff))
22: (bc) w0 = w7 ; [...] R7=4294967295
23: (95) exit
from 13 to 1: [...]
1: [...]
1: (b7) r0 = 0 ; R0_w=0
2: (95) exit
processed 24 insns (limit 1000000) max_states_per_insn 0 total_states 2 peak_states 2 mark_read 1
=====================
Verifier log above is for `(u32)[0; U32_MAX] (s32)< -1` use cases, where u32
range is used for initialization, followed by signed < operator. Note
how we use w6/w7 in this case for register initialization (it would be
R6/R7 for 64-bit types) and then `if w6 s< w7` for comparison at
instruction #17. It will be `if R6 < R7` for 64-bit unsigned comparison.
Above example gives a good impression of the overall structure of a BPF
programs generated for reg_bounds tests.
In the future, this "framework" can be extended to test not just
conditional jumps, but also arithmetic operations. Adding randomized
testing is another possibility.
Some implementation notes. We basically have our own generics-like
operations on numbers, where all the numbers are stored in u64, but how
they are interpreted is passed as runtime argument enum num_t. Further,
`struct range` represents a bounds range, and those are collected
together into a minimal `struct reg_state`, which collects range bounds
across all four numberical domains: u64, s64, u32, s64.
Based on these primitives and `enum op` representing possible
conditional operation (<, <=, >, >=, ==, !=), there is a set of generic
helpers to perform "range arithmetics", which is used to maintain struct
reg_state. We simulate what verifier will do for reg bounds of R6 and R7
registers using these range and reg_state primitives. Simulated
information is used to determine branch taken conclusion and expected
exact register state across all four number domains.
Implementation of "range arithmetics" is more generic than what verifier
is currently performing: it allows range over range comparisons and
adjustments. This is the intended end goal of this patch set overall and verifier
logic is enhanced in subsequent patches in this series to handle range
vs range operations, at which point selftests are extended to validate
these conditions as well. For now it's range vs const cases only.
Note that tests are split into multiple groups by their numeric types
for initialization of ranges and for comparison operation. This allows
to use test_progs's -j parallelization to speed up tests, as we now have
16 groups of parallel running tests. Overall reduction of running time
that allows is pretty good, we go down from more than 30 minutes to
slightly less than 5 minutes running time.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://lore.kernel.org/r/20231112010609.848406-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Running the mp_join selftest manually with the following command line:
./mptcp_join.sh -z -C
leads to some failures:
002 fastclose server test
# ...
rtx [fail] got 1 MP_RST[s] TX expected 0
# ...
rstrx [fail] got 1 MP_RST[s] RX expected 0
The problem is really in the wrong expectations for the RST checks
implied by the csum validation. Note that the same check is repeated
explicitly in the same test-case, with the correct expectation and
pass successfully.
Address the issue explicitly setting the correct expectation for
the failing checks.
Reported-by: Xiumei Mu <xmu@redhat.com>
Fixes: 6bf41020b7 ("selftests: mptcp: update and extend fastclose test-cases")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-5-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add selftests for cgroup1 hierarchy.
The result as follows,
$ tools/testing/selftests/bpf/test_progs --name=cgroup1_hierarchy
#36/1 cgroup1_hierarchy/test_cgroup1_hierarchy:OK
#36/2 cgroup1_hierarchy/test_root_cgid:OK
#36/3 cgroup1_hierarchy/test_invalid_level:OK
#36/4 cgroup1_hierarchy/test_invalid_cgid:OK
#36/5 cgroup1_hierarchy/test_invalid_hid:OK
#36/6 cgroup1_hierarchy/test_invalid_cgrp_name:OK
#36/7 cgroup1_hierarchy/test_invalid_cgrp_name2:OK
#36/8 cgroup1_hierarchy/test_sleepable_prog:OK
#36 cgroup1_hierarchy:OK
Summary: 1/8 PASSED, 0 SKIPPED, 0 FAILED
Besides, I also did some stress test similar to the patch #2 in this
series, as follows (with CONFIG_PROVE_RCU_LIST enabled):
- Continuously mounting and unmounting named cgroups in some tasks,
for example:
cgrp_name=$1
while true
do
mount -t cgroup -o none,name=$cgrp_name none /$cgrp_name
umount /$cgrp_name
done
- Continuously run this selftest concurrently,
while true; do ./test_progs --name=cgroup1_hierarchy; done
They can ran successfully without any RCU warnings in dmesg.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231111090034.4248-7-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Include the current pid in the classid cgroup path. This way, different
testers relying on classid-based configurations will have distinct classid
cgroup directories, enabling them to run concurrently. Additionally, we
leverage the current pid as the classid, ensuring unique identification.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231111090034.4248-4-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
If the net_cls subsystem is already mounted, attempting to mount it again
in setup_classid_environment() will result in a failure with the error code
EBUSY. Despite this, tmpfs will have been successfully mounted at
/sys/fs/cgroup/net_cls. Consequently, the /sys/fs/cgroup/net_cls directory
will be empty, causing subsequent setup operations to fail.
Here's an error log excerpt illustrating the issue when net_cls has already
been mounted at /sys/fs/cgroup/net_cls prior to running
setup_classid_environment():
- Before that change
$ tools/testing/selftests/bpf/test_progs --name=cgroup_v1v2
test_cgroup_v1v2:PASS:server_fd 0 nsec
test_cgroup_v1v2:PASS:client_fd 0 nsec
test_cgroup_v1v2:PASS:cgroup_fd 0 nsec
test_cgroup_v1v2:PASS:server_fd 0 nsec
run_test:PASS:skel_open 0 nsec
run_test:PASS:prog_attach 0 nsec
test_cgroup_v1v2:PASS:cgroup-v2-only 0 nsec
(cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup.procs
(cgroup_helpers.c:540: errno: No such file or directory) Opening cgroup classid: /sys/fs/cgroup/net_cls/cgroup-test-work-dir/net_cls.classid
run_test:PASS:skel_open 0 nsec
run_test:PASS:prog_attach 0 nsec
(cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup-test-work-dir/cgroup.procs
run_test:FAIL:join_classid unexpected error: 1 (errno 2)
test_cgroup_v1v2:FAIL:cgroup-v1v2 unexpected error: -1 (errno 2)
(cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup.procs
#44 cgroup_v1v2:FAIL
Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED
- After that change
$ tools/testing/selftests/bpf/test_progs --name=cgroup_v1v2
#44 cgroup_v1v2:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231111090034.4248-3-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull LoongArch updates from Huacai Chen:
- support PREEMPT_DYNAMIC with static keys
- relax memory ordering for atomic operations
- support BPF CPU v4 instructions for LoongArch
- some build and runtime warning fixes
* tag 'loongarch-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
selftests/bpf: Enable cpu v4 tests for LoongArch
LoongArch: BPF: Support signed mod instructions
LoongArch: BPF: Support signed div instructions
LoongArch: BPF: Support 32-bit offset jmp instructions
LoongArch: BPF: Support unconditional bswap instructions
LoongArch: BPF: Support sign-extension mov instructions
LoongArch: BPF: Support sign-extension load instructions
LoongArch: Add more instruction opcodes and emit_* helpers
LoongArch/smp: Call rcutree_report_cpu_starting() earlier
LoongArch: Relax memory ordering for atomic operations
LoongArch: Mark __percpu functions as always inline
LoongArch: Disable module from accessing external data directly
LoongArch: Support PREEMPT_DYNAMIC with static keys
With latest clang18 (main branch of llvm-project repo), when building bpf selftests,
[~/work/bpf-next (master)]$ make -C tools/testing/selftests/bpf LLVM=1 -j
The following compilation error happens:
fatal error: error in backend: Branch target out of insn range
...
Stack dump:
0. Program arguments: clang -g -Wall -Werror -D__TARGET_ARCH_x86 -mlittle-endian
-I/home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/include
-I/home/yhs/work/bpf-next/tools/testing/selftests/bpf -I/home/yhs/work/bpf-next/tools/include/uapi
-I/home/yhs/work/bpf-next/tools/testing/selftests/usr/include -idirafter
/home/yhs/work/llvm-project/llvm/build.18/install/lib/clang/18/include -idirafter /usr/local/include
-idirafter /usr/include -Wno-compare-distinct-pointer-types -DENABLE_ATOMICS_TESTS -O2 --target=bpf
-c progs/pyperf180.c -mcpu=v3 -o /home/yhs/work/bpf-next/tools/testing/selftests/bpf/pyperf180.bpf.o
1. <eof> parser at end of file
2. Code generation
...
The compilation failure only happens to cpu=v2 and cpu=v3. cpu=v4 is okay
since cpu=v4 supports 32-bit branch target offset.
The above failure is due to upstream llvm patch [1] where some inlining behavior
are changed in clang18.
To workaround the issue, previously all 180 loop iterations are fully unrolled.
The bpf macro __BPF_CPU_VERSION__ (implemented in clang18 recently) is used to avoid
unrolling changes if cpu=v4. If __BPF_CPU_VERSION__ is not available and the
compiler is clang18, the unrollng amount is unconditionally reduced.
[1] 1a2e77cf9e
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20231110193644.3130906-1-yonghong.song@linux.dev
When BPF program is verified in privileged mode, BPF verifier allows
bounded loops. This means that from CFG point of view there are
definitely some back-edges. Original commit adjusted check_cfg() logic
to not detect back-edges in control flow graph if they are resulting
from conditional jumps, which the idea that subsequent full BPF
verification process will determine whether such loops are bounded or
not, and either accept or reject the BPF program. At least that's my
reading of the intent.
Unfortunately, the implementation of this idea doesn't work correctly in
all possible situations. Conditional jump might not result in immediate
back-edge, but just a few unconditional instructions later we can arrive
at back-edge. In such situations check_cfg() would reject BPF program
even in privileged mode, despite it might be bounded loop. Next patch
adds one simple program demonstrating such scenario.
To keep things simple, instead of trying to detect back edges in
privileged mode, just assume every back edge is valid and let subsequent
BPF verification prove or reject bounded loops.
Note a few test changes. For unknown reason, we have a few tests that
are specified to detect a back-edge in a privileged mode, but looking at
their code it seems like the right outcome is passing check_cfg() and
letting subsequent verification to make a decision about bounded or not
bounded looping.
Bounded recursion case is also interesting. The example should pass, as
recursion is limited to just a few levels and so we never reach maximum
number of nested frames and never exhaust maximum stack depth. But the
way that max stack depth logic works today it falsely detects this as
exceeding max nested frame count. This patch series doesn't attempt to
fix this orthogonal problem, so we just adjust expected verifier failure.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Fixes: 2589726d12 ("bpf: introduce bounded loops")
Reported-by: Hao Sun <sunhao.th@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231110061412.2995786-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a dedicated selftests to try to set up conditions to have a state
with same first and last instruction index, but it actually is a loop
3->4->1->2->3. This confuses mark_chain_precision() if verifier doesn't
take into account jump history.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231110002638.4168352-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
ldimm64 instructions are 16-byte long, and so have to be handled
appropriately in check_cfg(), just like the rest of BPF verifier does.
This has implications in three places:
- when determining next instruction for non-jump instructions;
- when determining next instruction for callback address ldimm64
instructions (in visit_func_call_insn());
- when checking for unreachable instructions, where second half of
ldimm64 is expected to be unreachable;
We take this also as an opportunity to report jump into the middle of
ldimm64. And adjust few test_verifier tests accordingly.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Reported-by: Hao Sun <sunhao.th@gmail.com>
Fixes: 475fb78fbf ("bpf: verifier (add branch/goto checks)")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231110002638.4168352-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Crossbuilding selftests/bpf for architecture arm64, format specifies
type error show up like.
xskxceiver.c:912:34: error: format specifies type 'int' but the argument
has type '__u64' (aka 'unsigned long long') [-Werror,-Wformat]
ksft_print_msg("[%s] expected meta_count [%d], got meta_count [%d]\n",
~~
%llu
__func__, pkt->pkt_nb, meta->count);
^~~~~~~~~~~
xskxceiver.c:929:55: error: format specifies type 'unsigned long long' but
the argument has type 'u64' (aka 'unsigned long') [-Werror,-Wformat]
ksft_print_msg("Frag invalid addr: %llx len: %u\n", addr, len);
~~~~ ^~~~
Fixing the issues by casting to (unsigned long long) and changing the
specifiers to be %llu from %d and %u, since with u64s it might be %llx
or %lx, depending on architecture.
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Link: https://lore.kernel.org/r/20231109174328.1774571-1-anders.roxell@linaro.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch demonstrates that verifier changes earlier in this series
result in bpf_refcount_acquire(mapval->stashed_kptr) passing
verification. The added test additionally validates that stashing a kptr
in mapval and - in a separate BPF program - refcount_acquiring the kptr
without unstashing works as expected at runtime.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20231107085639.3016113-7-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test added in this patch exercises the logic fixed in the previous
patch in this series. Before the previous patch's changes,
bpf_refcount_acquire accepts MAYBE_NULL local kptrs; after the change
the verifier correctly rejects the such a call.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20231107085639.3016113-3-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
