- 24 Aug, 2021 24 commits
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Kumar Kartikeya Dwivedi authored
This adds support for retrieval and printing for devmap_xmit total and mutli mode tracepoint. For multi mode, we keep a hash map entry for each redirection stream, such that we can dynamically add and remove entries on output. The from_match and to_match will be set by individual samples when setting up the XDP program on these devices. The multi mode tracepoint is also handy for xdp_redirect_map_multi, where up to 32 devices can be specified. Also add samples_init_pre_load macro to finally set up the resized maps and mmap them in place for low overhead stats retrieval. Signed-off-by:
Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by:
Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210821002010.845777-12-memxor@gmail.com
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Kumar Kartikeya Dwivedi authored
This adds support for the devmap_xmit tracepoint, and its multi device variant that can be used to obtain streams for each individual net_device to net_device redirection. This is useful for decomposing total xmit stats in xdp_monitor. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This consolidates retrieval and printing into the XDP sample helper. For the kthread stats, it expands xdp_stats separately with its own per-CPU stats. For cpumap enqueue, we display FROM->TO stats also with its per-CPU stats. The help out explains in detail the various aspects of the output. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
These are invoked in two places, when the XDP frame or SKB (for generic XDP) enqueued to the ptr_ring (cpumap_enqueue) and when kthread processes the frame after invoking the CPUMAP program for it (returning stats for the batch). We use cpumap_map_id to filter on the map_id as a way to avoid printing incorrect stats for parallel sessions of xdp_redirect_cpu. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This implements the retrieval and printing, as well the help output. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This would allow us to store stats for each XDP action, including their per-CPU counts. Consolidating this here allows all redirect samples to detect xdp_exception events. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This implements per-errno reporting (for the ones we explicitly recognize), adds some help output, and implements the stats retrieval and printing functions. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This adds the shared BPF file that will be used going forward for sharing tracepoint programs among XDP redirect samples. Since vmlinux.h conflicts with tools/include for READ_ONCE/WRITE_ONCE and ARRAY_SIZE, they are copied in to xdp_sample.bpf.h along with other helpers that will be required. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
This file implements some common helpers to consolidate differences in features and functionality between the various XDP samples and give them a consistent look, feel, and reporting capabilities. This commit only adds support for receive statistics, which does not rely on any tracepoint, but on the XDP program installed on the device by each XDP redirect sample. Some of the key features are: * A concise output format accompanied by helpful text explaining its fields. * An elaborate output format building upon the concise one, and folding out details in case of errors and staying out of view otherwise. * Printing driver names for devices redirecting packets. * Getting mac address for interface. * Printing summarized total statistics for the entire session. * Ability to dynamically switch between concise and verbose mode, using SIGQUIT (Ctrl + \). In later patches, the support will be extended for each tracepoint with its own custom output in concise and verbose mode. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
Instead of copying the whole header in, just add the struct definitions we need for now. In the future it can be synced as a copy of in-tree header if required. Signed-off-by:
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Kumar Kartikeya Dwivedi authored
cookie_uid_helper_example.c: In function ‘main’: cookie_uid_helper_example.c:178:69: warning: ‘ -j ACCEPT’ directive writing 10 bytes into a region of size between 8 and 58 [-Wformat-overflow=] 178 | sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", | ^~~~~~~~~~ /home/kkd/src/linux/samples/bpf/cookie_uid_helper_example.c:178:9: note: ‘sprintf’ output between 53 and 103 bytes into a destination of size 100 178 | sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 179 | file); | ~~~~~ Fix by using snprintf and a sufficiently sized buffer. tracex4_user.c:35:15: warning: ‘write’ reading 12 bytes from a region of size 11 [-Wstringop-overread] 35 | key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ Use size as 11. Signed-off-by: -
Andrey Ignatov authored
Fix a verifier bug found by smatch static checker in [0]. This problem has never been seen in prod to my best knowledge. Fixing it still seems to be a good idea since it's hard to say for sure whether it's possible or not to have a scenario where a combination of convert_ctx_access() and a narrow load would lead to an out of bound write. When narrow load is handled, one or two new instructions are added to insn_buf array, but before it was only checked that cnt >= ARRAY_SIZE(insn_buf) And it's safe to add a new instruction to insn_buf[cnt++] only once. The second try will lead to out of bound write. And this is what can happen if `shift` is set. Fix it by making sure that if the BPF_RSH instruction has to be added in addition to BPF_AND then there is enough space for two more instructions in insn_buf. The full report [0] is below: kernel/bpf/verifier.c:12304 convert_ctx_accesses() warn: offset 'cnt' incremented past end of array kernel/bpf/verifier.c:12311 convert_ctx_accesses() warn: offset 'cnt' incremented past end of array kernel/bpf/verifier.c 12282 12283 insn->off = off & ~(size_default - 1); 12284 insn->code = BPF_LDX | BPF_MEM | size_code; 12285 } 12286 12287 target_size = 0; 12288 cnt = convert_ctx_access(type, insn, insn_buf, env->prog, 12289 &target_size); 12290 if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf) || ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Bounds check. 12291 (ctx_field_size && !target_size)) { 12292 verbose(env, "bpf verifier is misconfigured\n"); 12293 return -EINVAL; 12294 } 12295 12296 if (is_narrower_load && size < target_size) { 12297 u8 shift = bpf_ctx_narrow_access_offset( 12298 off, size, size_default) * 8; 12299 if (ctx_field_size <= 4) { 12300 if (shift) 12301 insn_buf[cnt++] = BPF_ALU32_IMM(BPF_RSH, ^^^^^ increment beyond end of array 12302 insn->dst_reg, 12303 shift); --> 12304 insn_buf[cnt++] = BPF_ALU32_IMM(BPF_AND, insn->dst_reg, ^^^^^ out of bounds write 12305 (1 << size * 8) - 1); 12306 } else { 12307 if (shift) 12308 insn_buf[cnt++] = BPF_ALU64_IMM(BPF_RSH, 12309 insn->dst_reg, 12310 shift); 12311 insn_buf[cnt++] = BPF_ALU64_IMM(BPF_AND, insn->dst_reg, ^^^^^^^^^^^^^^^ Same. 12312 (1ULL << size * 8) - 1); 12313 } 12314 } 12315 12316 new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt); 12317 if (!new_prog) 12318 return -ENOMEM; 12319 12320 delta += cnt - 1; 12321 12322 /* keep walking new program and skip insns we just inserted */ 12323 env->prog = new_prog; 12324 insn = new_prog->insnsi + i + delta; 12325 } 12326 12327 return 0; 12328 } [0] https://lore.kernel.org/bpf/20210817050843.GA21456@kili/ v1->v2: - clarify that problem was only seen by static checker but not in prod; Fixes: 46f53a65 ("bpf: Allow narrow loads with offset > 0") Reported-by:Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
Andrey Ignatov <rdna@fb.com> Signed-off-by:
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Alexei Starovoitov authored
Xu Liu says: ==================== We'd like to be able to identify netns from sk_msg hooks to accelerate local process communication form different netns. ==================== Signed-off-by: -
Xu Liu authored
Add test to use get_netns_cookie() from BPF_PROG_TYPE_SK_MSG. Signed-off-by:
Xu Liu <liuxu623@gmail.com> Signed-off-by:
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Xu Liu authored
We'd like to be able to identify netns from sk_msg hooks to accelerate local process communication form different netns. Signed-off-by:
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Alexei Starovoitov authored
Li Zhijian says: ==================== Fix a few issues reported by 0Day/LKP during runing selftests/bpf. Changelog: V2: - folded previous similar standalone patch to [1/5], and add acked tag from Song Liu - add acked tag to [2/5], [3/5] from Song Liu - [4/5]: move test_bpftool.py to TEST_PROGS_EXTENDED, files in TEST_GEN_PROGS_EXTENDED are generated by make. Otherwise, it will break out-of-tree install: 'make O=/kselftest-build SKIP_TARGETS= V=1 -C tools/testing/selftests install INSTALL_PATH=/kselftest-install' - [5/5]: new patch ==================== Signed-off-by: -
Li Zhijian authored
This would happend when we run the tests after install kselftests root@lkp-skl-d01 ~# /kselftests/run_kselftest.sh -t bpf:test_doc_build.sh TAP version 13 1..1 # selftests: bpf: test_doc_build.sh perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = (unset), LC_ALL = (unset), LC_ADDRESS = "en_US.UTF-8", LC_NAME = "en_US.UTF-8", LC_MONETARY = "en_US.UTF-8", LC_PAPER = "en_US.UTF-8", LC_IDENTIFICATION = "en_US.UTF-8", LC_TELEPHONE = "en_US.UTF-8", LC_MEASUREMENT = "en_US.UTF-8", LC_TIME = "en_US.UTF-8", LC_NUMERIC = "en_US.UTF-8", LANG = "en_US.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). # skip: bpftool files not found! # ok 1 selftests: bpf: test_doc_build.sh # SKIP Signed-off-by:Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by:
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Li Zhijian authored
test_bpftool.sh relies on bpftool and test_bpftool.py. 'make install' will install bpftool to INSTALL_PATH/bpf/bpftool, and export it to PATH so that it can be used after installing. Signed-off-by:
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Li Zhijian authored
For 'make run_tests': selftests will build bpftool into tools/testing/selftests/bpf/tools/sbin/bpftool by default. ================== root@lkp-skl-d01 /opt/rootfs/v5.14-rc4# make -C tools/testing/selftests/bpf run_tests make: Entering directory '/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf' MKDIR include MKDIR libbpf MKDIR bpftool [...] GEN /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/tools/build/bpftool/profiler.skel.h CC /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/tools/build/bpftool/prog.o GEN /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/tools/build/bpftool/pid_iter.skel.h CC /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/tools/build/bpftool/pids.o LINK /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/tools/build/bpftool/bpftool INSTALL bpftool GEN vmlinux.h [...] # test_feature_dev_json (test_bpftool.TestBpftool) ... ERROR # test_feature_kernel (test_bpftool.TestBpftool) ... ERROR # test_feature_kernel_full (test_bpftool.TestBpftool) ... ERROR # test_feature_kernel_full_vs_not_full (test_bpftool.TestBpftool) ... ERROR # test_feature_macros (test_bpftool.TestBpftool) ... Error: bug: failed to retrieve CAP_BPF status: Invalid argument # ERROR # # ====================================================================== # ERROR: test_feature_dev_json (test_bpftool.TestBpftool) # ---------------------------------------------------------------------- # Traceback (most recent call last): # File "/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/test_bpftool.py", line 57, in wrapper # return f(*args, iface, **kwargs) # File "/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/test_bpftool.py", line 82, in test_feature_dev_json # res = bpftool_json(["feature", "probe", "dev", iface]) # File "/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/test_bpftool.py", line 42, in bpftool_json # res = _bpftool(args) # File "/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/test_bpftool.py", line 34, in _bpftool # return subprocess.check_output(_args) # File "/usr/lib/python3.7/subprocess.py", line 395, in check_output # **kwargs).stdout # File "/usr/lib/python3.7/subprocess.py", line 487, in run # output=stdout, stderr=stderr) # subprocess.CalledProcessError: Command '['bpftool', '-j', 'feature', 'probe', 'dev', 'dummy0']' returned non-zero exit status 255. # ================== Signed-off-by:
Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20210820015556.23276-4-lizhijian@cn.fujitsu.com
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Li Zhijian authored
Previously, it fails as below: ------------- root@lkp-skl-d01 /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf# ./test_doc_build.sh ++ realpath --relative-to=/opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf ./test_doc_build.sh + SCRIPT_REL_PATH=test_doc_build.sh ++ dirname test_doc_build.sh + SCRIPT_REL_DIR=. ++ realpath /opt/rootfs/v5.14-rc4/tools/testing/selftests/bpf/./../../../../ + KDIR_ROOT_DIR=/opt/rootfs/v5.14-rc4 + cd /opt/rootfs/v5.14-rc4 + for tgt in docs docs-clean + make -s -C /opt/rootfs/v5.14-rc4/. docs make: *** No rule to make target 'docs'. Stop. + for tgt in docs docs-clean + make -s -C /opt/rootfs/v5.14-rc4/. docs-clean make: *** No rule to make target 'docs-clean'. Stop. ----------- Reported-by:
kernel test robot <lkp@intel.com> Signed-off-by:
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Li Zhijian authored
0Day robot observed that it's easily timeout on a heavy load host. ------------------- # selftests: bpf: test_maps # Fork 1024 tasks to 'test_update_delete' # Fork 1024 tasks to 'test_update_delete' # Fork 100 tasks to 'test_hashmap' # Fork 100 tasks to 'test_hashmap_percpu' # Fork 100 tasks to 'test_hashmap_sizes' # Fork 100 tasks to 'test_hashmap_walk' # Fork 100 tasks to 'test_arraymap' # Fork 100 tasks to 'test_arraymap_percpu' # Failed sockmap unexpected timeout not ok 3 selftests: bpf: test_maps # exit=1 # selftests: bpf: test_lru_map # nr_cpus:8 ------------------- Since this test will be scheduled by 0Day to a random host that could have only a few cpus(2-8), enlarge the timeout to avoid a false NG report. In practice, i tried to pin it to only one cpu by 'taskset 0x01 ./test_maps', and knew 10S is likely enough, but i still perfer to a larger value 30. Reported-by:
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Yucong Sun authored
This patch extends wait time in timer_mim. As observed in slow CI environment, it is possible to have interrupt/preemption long enough to cause the test to fail, almost 1 failure in 5 runs. Signed-off-by:
Yucong Sun <fallentree@fb.com> Signed-off-by:
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Alexei Starovoitov authored
Dave Marchevsky says: ==================== The cgroup_bpf struct has a few arrays (effective, progs, and flags) of size MAX_BPF_ATTACH_TYPE. These are meant to separate progs by their attach type, currently represented by the bpf_attach_type enum. There are some bpf_attach_type values which are not valid attach types for cgroup bpf programs. Programs with these attach types will never be handled by cgroup_bpf_{attach,detach} and thus will never be held in cgroup_bpf structs. Even if such programs did make it into their reserved slot in those arrays, they would never be executed. Accordingly we can migrate to a new internal cgroup_bpf-specific enum for these arrays, saving some bytes per cgroup and making it more obvious which BPF programs belong there. netns_bpf_attach_type is an existing example of this pattern, let's do similar for cgroup_bpf. v1->v2: Address Daniel's comments * Reverse xmas tree ordering for def changes * Helper macro to reduce to_cgroup_bpf_attach_type boilerplate * checkpatch.pl complains: "ERROR: Macros with complex values should be enclosed in parentheses". Found some existing macros (do 'git grep "define case"') which get same complaint. Think it's fine to keep as-is since it's immediately undef'd. * Remove CG_BPF_ prefix from cgroup_bpf_attach_type * Although I agree that the prefix is redundant, the de-prefixed names feel a bit too 'general' given the internal use of the enum. e.g. when someone sees CGROUP_INET6_BIND it's not obvious that it should only be used in certain ways internally. * Don't feel strongly about this, just my thoughts as a noob to the internals. * Rebase onto latest bpf-next/master * No significant conflicts, some small boilerplate adjustments needed to catch up to Andrii's "bpf: Refactor BPF_PROG_RUN_ARRAY family of macros into functions" change ==================== Signed-off-by: -
Dave Marchevsky authored
Add an enum (cgroup_bpf_attach_type) containing only valid cgroup_bpf attach types and a function to map bpf_attach_type values to the new enum. Inspired by netns_bpf_attach_type. Then, migrate cgroup_bpf to use cgroup_bpf_attach_type wherever possible. Functionality is unchanged as attach_type_to_prog_type switches in bpf/syscall.c were preventing non-cgroup programs from making use of the invalid cgroup_bpf array slots. As a result struct cgroup_bpf uses 504 fewer bytes relative to when its arrays were sized using MAX_BPF_ATTACH_TYPE. bpf_cgroup_storage is notably not migrated as struct bpf_cgroup_storage_key is part of uapi and contains a bpf_attach_type member which is not meant to be opaque. Similarly, bpf_cgroup_link continues to report its bpf_attach_type member to userspace via fdinfo and bpf_link_info. To ease disambiguation, bpf_attach_type variables are renamed from 'type' to 'atype' when changed to cgroup_bpf_attach_type. Signed-off-by:
Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by:
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- 23 Aug, 2021 1 commit
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Jiang Wang authored
Commit 94531cfc ("af_unix: Add unix_stream_proto for sockmap") introduced a bug for af_unix SEQPACKET type. In unix_shutdown, the unhash function will call prot->unhash(), which is NULL for SEQPACKET. And kernel will panic. On ARM32, it will show following messages: (it likely affects x86 too). Fix the bug by checking the prot->unhash is NULL or not first. Kernel log: <--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = 2fba1ffb *pgd=00000000 Internal error: Oops: 80000005 [#1] PREEMPT SMP THUMB2 Modules linked in: CPU: 1 PID: 1999 Comm: falkon Tainted: G W 5.14.0-rc5-01175-g94531cfc-dirty #9240 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) PC is at 0x0 LR is at unix_shutdown+0x81/0x1a8 pc : [<00000000>] lr : [<c08f3311>] psr: 600f0013 sp : e45aff70 ip : e463a3c0 fp : beb54f04 r10: 00000125 r9 : e45ae000 r8 : c4a56664 r7 : 00000001 r6 : c4a56464 r5 : 00000001 r4 : c4a56400 r3 : 00000000 r2 : c5a6b180 r1 : 00000000 r0 : c4a56400 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 50c5387d Table: 05aa804a DAC: 00000051 Register r0 information: slab PING start c4a56400 pointer offset 0 Register r1 information: NULL pointer Register r2 information: slab task_struct start c5a6b180 pointer offset 0 Register r3 information: NULL pointer Register r4 information: slab PING start c4a56400 pointer offset 0 Register r5 information: non-paged memory Register r6 information: slab PING start c4a56400 pointer offset 100 Register r7 information: non-paged memory Register r8 information: slab PING start c4a56400 pointer offset 612 Register r9 information: non-slab/vmalloc memory Register r10 information: non-paged memory Register r11 information: non-paged memory Register r12 information: slab filp start e463a3c0 pointer offset 0 Process falkon (pid: 1999, stack limit = 0x9ec48895) Stack: (0xe45aff70 to 0xe45b0000) ff60: e45ae000 c5f26a00 00000000 00000125 ff80: c0100264 c07f7fa3 beb54f04 fffffff7 00000001 e6f3fc0e b5e5e9ec beb54ec4 ffa0: b5da0ccc c010024b b5e5e9ec beb54ec4 0000000f 00000000 00000000 beb54ebc ffc0: b5e5e9ec beb54ec4 b5da0ccc 00000125 beb54f58 00785238 beb5529c beb54f04 ffe0: b5da1e24 beb54eac b301385c b62b6ee8 600f0030 0000000f 00000000 00000000 [<c08f3311>] (unix_shutdown) from [<c07f7fa3>] (__sys_shutdown+0x2f/0x50) [<c07f7fa3>] (__sys_shutdown) from [<c010024b>] (__sys_trace_return+0x1/0x16) Exception stack(0xe45affa8 to 0xe45afff0) Fixes: 94531cfc ("af_unix: Add unix_stream_proto for sockmap") Reported-by:
Dmitry Osipenko <digetx@gmail.com> Signed-off-by:
Jiang Wang <jiang.wang@bytedance.com> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Tested-by:
Kuniyuki Iwashima <kuniyu@amazon.co.jp> Link: https://lore.kernel.org/bpf/20210821180738.1151155-1-jiang.wang@bytedance.com
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- 19 Aug, 2021 7 commits
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Prankur Gupta authored
Adding selftests for the newly added functionality to call bpf_setsockopt() and bpf_getsockopt() from setsockopt BPF programs. Test Details: 1. BPF Program Checks for changes in IPV6_TCLASS(SOL_IPV6) via setsockopt If the cca for the socket is not cubic do nothing If the newly set value for IPV6_TCLASS is 45 (0x2d) (as per our use-case) then change the cc from cubic to reno 2. User Space Program Creates an AF_INET6 socket and set the cca for that to be "cubic" Attach the program and set the IPV6_TCLASS to 0x2d using setsockopt Verify the cca for the socket changed to reno Signed-off-by:
Prankur Gupta <prankgup@fb.com> Signed-off-by:
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Prankur Gupta authored
Add logic to call bpf_setsockopt() and bpf_getsockopt() from setsockopt BPF programs. An example use case is when the user sets the IPV6_TCLASS socket option, we would also like to change the tcp-cc for that socket. We don't have any use case for calling bpf_setsockopt() from supposedly read- only sys_getsockopt(), so it is made available to BPF_CGROUP_SETSOCKOPT only at this point. Signed-off-by:
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Stanislav Fomichev authored
Same as previous patch but for the keys. memdup_bpfptr is renamed to kvmemdup_bpfptr (and converted to kvmalloc). Signed-off-by:
Stanislav Fomichev <sdf@google.com> Signed-off-by:
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Stanislav Fomichev authored
Use kvmalloc/kvfree for temporary value when manipulating a map via syscall. kmalloc might not be sufficient for percpu maps where the value is big (and further multiplied by hundreds of CPUs). Can be reproduced with netcnt test on qemu with "-smp 255". Signed-off-by:
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Yucong Sun authored
This patch adds a 1ms delay to reduce flakyness of the test. Signed-off-by:
Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210819163609.2583758-1-fallentree@fb.com
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Yonghong Song authored
Andrii reported that libbpf CI hit the following oops when running selftest send_signal: [ 1243.160719] BUG: kernel NULL pointer dereference, address: 0000000000000030 [ 1243.161066] #PF: supervisor read access in kernel mode [ 1243.161066] #PF: error_code(0x0000) - not-present page [ 1243.161066] PGD 0 P4D 0 [ 1243.161066] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 1243.161066] CPU: 1 PID: 882 Comm: new_name Tainted: G O 5.14.0-rc5 #1 [ 1243.161066] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [ 1243.161066] RIP: 0010:bpf_overflow_handler+0x9a/0x1e0 [ 1243.161066] Code: 5a 84 c0 0f 84 06 01 00 00 be 66 02 00 00 48 c7 c7 6d 96 07 82 48 8b ab 18 05 00 00 e8 df 55 eb ff 66 90 48 8d 75 48 48 89 e7 <ff> 55 30 41 89 c4 e8 fb c1 f0 ff 84 c0 0f 84 94 00 00 00 e8 6e 0f [ 1243.161066] RSP: 0018:ffffc900000c0d80 EFLAGS: 00000046 [ 1243.161066] RAX: 0000000000000002 RBX: ffff8881002e0dd0 RCX: 00000000b4b47cf8 [ 1243.161066] RDX: ffffffff811dcb06 RSI: 0000000000000048 RDI: ffffc900000c0d80 [ 1243.161066] RBP: 0000000000000000 R08: 0000000000000000 R09: 1a9d56bb00000000 [ 1243.161066] R10: 0000000000000001 R11: 0000000000080000 R12: 0000000000000000 [ 1243.161066] R13: ffffc900000c0e00 R14: ffffc900001c3c68 R15: 0000000000000082 [ 1243.161066] FS: 00007fc0be2d3380(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 [ 1243.161066] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1243.161066] CR2: 0000000000000030 CR3: 0000000104f8e000 CR4: 00000000000006e0 [ 1243.161066] Call Trace: [ 1243.161066] <IRQ> [ 1243.161066] __perf_event_overflow+0x4f/0xf0 [ 1243.161066] perf_swevent_hrtimer+0x116/0x130 [ 1243.161066] ? __lock_acquire+0x378/0x2730 [ 1243.161066] ? __lock_acquire+0x372/0x2730 [ 1243.161066] ? lock_is_held_type+0xd5/0x130 [ 1243.161066] ? find_held_lock+0x2b/0x80 [ 1243.161066] ? lock_is_held_type+0xd5/0x130 [ 1243.161066] ? perf_event_groups_first+0x80/0x80 [ 1243.161066] ? perf_event_groups_first+0x80/0x80 [ 1243.161066] __hrtimer_run_queues+0x1a3/0x460 [ 1243.161066] hrtimer_interrupt+0x110/0x220 [ 1243.161066] __sysvec_apic_timer_interrupt+0x8a/0x260 [ 1243.161066] sysvec_apic_timer_interrupt+0x89/0xc0 [ 1243.161066] </IRQ> [ 1243.161066] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 1243.161066] RIP: 0010:finish_task_switch+0xaf/0x250 [ 1243.161066] Code: 31 f6 68 90 2a 09 81 49 8d 7c 24 18 e8 aa d6 03 00 4c 89 e7 e8 12 ff ff ff 4c 89 e7 e8 ca 9c 80 00 e8 35 af 0d 00 fb 4d 85 f6 <58> 74 1d 65 48 8b 04 25 c0 6d 01 00 4c 3b b0 a0 04 00 00 74 37 f0 [ 1243.161066] RSP: 0018:ffffc900001c3d18 EFLAGS: 00000282 [ 1243.161066] RAX: 000000000000031f RBX: ffff888104cf4980 RCX: 0000000000000000 [ 1243.161066] RDX: 0000000000000000 RSI: ffffffff82095460 RDI: ffffffff820adc4e [ 1243.161066] RBP: ffffc900001c3d58 R08: 0000000000000001 R09: 0000000000000001 [ 1243.161066] R10: 0000000000000001 R11: 0000000000080000 R12: ffff88813bd2bc80 [ 1243.161066] R13: ffff8881002e8000 R14: ffff88810022ad80 R15: 0000000000000000 [ 1243.161066] ? finish_task_switch+0xab/0x250 [ 1243.161066] ? finish_task_switch+0x70/0x250 [ 1243.161066] __schedule+0x36b/0xbb0 [ 1243.161066] ? _raw_spin_unlock_irqrestore+0x2d/0x50 [ 1243.161066] ? lockdep_hardirqs_on+0x79/0x100 [ 1243.161066] schedule+0x43/0xe0 [ 1243.161066] pipe_read+0x30b/0x450 [ 1243.161066] ? wait_woken+0x80/0x80 [ 1243.161066] new_sync_read+0x164/0x170 [ 1243.161066] vfs_read+0x122/0x1b0 [ 1243.161066] ksys_read+0x93/0xd0 [ 1243.161066] do_syscall_64+0x35/0x80 [ 1243.161066] entry_SYSCALL_64_after_hwframe+0x44/0xae The oops can also be reproduced with the following steps: ./vmtest.sh -s # at qemu shell cd /root/bpf && while true; do ./test_progs -t send_signal Further analysis showed that the failure is introduced with commit b89fbfbb ("bpf: Implement minimal BPF perf link"). With the above commit, the following scenario becomes possible: cpu1 cpu2 hrtimer_interrupt -> bpf_overflow_handler (due to closing link_fd) bpf_perf_link_release -> perf_event_free_bpf_prog -> perf_event_free_bpf_handler -> WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler) event->prog = NULL bpf_prog_run(event->prog, &ctx) In the above case, the event->prog is NULL for bpf_prog_run, hence causing oops. To fix the issue, check whether event->prog is NULL or not. If it is, do not call bpf_prog_run. This seems working as the above reproducible step runs more than one hour and I didn't see any failures. Fixes: b89fbfbb ("bpf: Implement minimal BPF perf link") Signed-off-by:
Yonghong Song <yhs@fb.com> Signed-off-by:
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Daniel Borkmann authored
The BPF interpreter as well as x86-64 BPF JIT were both in line by allowing up to 33 tail calls (however odd that number may be!). Recently, this was changed for the interpreter to reduce it down to 32 with the assumption that this should have been the actual limit "which is in line with the behavior of the x86 JITs" according to b61a28cf ("bpf: Fix off-by-one in tail call count limiting"). Paul recently reported: I'm a bit surprised by this because I had previously tested the tail call limit of several JIT compilers and found it to be 33 (i.e., allowing chains of up to 34 programs). I've just extended a test program I had to validate this again on the x86-64 JIT, and found a limit of 33 tail calls again [1]. Also note we had previously changed the RISC-V and MIPS JITs to allow up to 33 tail calls [2, 3], for consistency with other JITs and with the interpreter. We had decided to increase these two to 33 rather than decrease the other JITs to 32 for backward compatibility, though that probably doesn't matter much as I'd expect few people to actually use 33 tail calls. [1] https://github.com/pchaigno/tail-call-bench/commit/ae7887482985b4b1745c9b2ef7ff9ae506c82886 [2] 96bc4432 ("bpf, riscv: Limit to 33 tail calls") [3] e49e6f6d ("bpf, mips: Limit to 33 tail calls") Therefore, revert b61a28cf to re-align interpreter to limit a maximum of 33 tail calls. While it is unlikely to hit the limit for the vast majority, programs in the wild could one way or another depend on this, so lets rather be a bit more conservative, and lets align the small remainder of JITs to 33. If needed in future, this limit could be slightly increased, but not decreased. Fixes: b61a28cf ("bpf: Fix off-by-one in tail call count limiting") Reported-by:
Paul Chaignon <paul@cilium.io> Signed-off-by:
Johan Almbladh <johan.almbladh@anyfinetworks.com> Acked-by:
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- 18 Aug, 2021 3 commits
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Xu Liu authored
Add test to use get_netns_cookie() from BPF_PROG_TYPE_SOCK_OPS. Signed-off-by:
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Xu Liu authored
We'd like to be able to identify netns from sockops hooks to accelerate local process communication form different netns. Signed-off-by:
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Grant Seltzer authored
This patch renames a documentation libbpf.rst to index.rst. In order for readthedocs.org to pick this file up and properly build the documentation site. It also changes the title type of the ABI subsection in the naming convention doc. This is so that readthedocs.org doesn't treat this section as a separate document. Signed-off-by:
Grant Seltzer <grantseltzer@gmail.com> Signed-off-by:
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- 17 Aug, 2021 5 commits
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Colin Ian King authored
The variable allow is being initialized with a value that is never read, it is being updated later on. The assignment is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by:Colin Ian King <colin.king@canonical.com> Signed-off-by:
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Andrii Nakryiko authored
Yonghong Song says: ==================== The bpf selftest send_signal() is flaky for its subtests trying to send signals in softirq/nmi context. To reduce flakiness, the signal-targetted process priority is boosted, which should minimize preemption of that process and improve the possibility that the underlying task in softirq/nmi context is the bpf_send_signal() wanted task. Patch #1 did a refactoring to use ASSERT_* instead of old CHECK macros. Patch #2 did actual change of boosting priority. Changelog: v1 -> v2: remove skip logic where the underlying task in interrupt context is not the intended one. ==================== Signed-off-by: -
Yonghong Song authored
libbpf CI has reported send_signal test is flaky although I am not able to reproduce it in my local environment. But I am able to reproduce with on-demand libbpf CI ([1]). Through code analysis, the following is possible reason. The failed subtest runs bpf program in softirq environment. Since bpf_send_signal() only sends to a fork of "test_progs" process. If the underlying current task is not "test_progs", bpf_send_signal() will not be triggered and the subtest will fail. To reduce the chances where the underlying process is not the intended one, this patch boosted scheduling priority to -20 (highest allowed by setpriority() call). And I did 10 runs with on-demand libbpf CI with this patch and I didn't observe any failures. [1] https://github.com/libbpf/libbpf/actions/workflows/ondemand.ymlSigned-off-by:
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Yonghong Song authored
Replace CHECK in send_signal.c with ASSERT_* macros as ASSERT_* macros are generally preferred. There is no funcitonality change. Signed-off-by:
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Andrii Nakryiko authored
Yucong Sun says: ==================== This short series adds two new switches to test_progs, "-a" and "-d", adding support for both exact string matching, as well as '*' wildcards. It also cleans up the output to make it possible to generate allowlist/denylist using common cli tools. ==================== Signed-off-by:
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