kernel/linux.git/samples/bpf, branch v4.20.5

samples: bpf: fix: error handling regarding kprobe_events

2019-01-26T08:20:42+00:00

[ Upstream commit 5a863813216ce79e16a8c1503b2543c528b778b6 ] Currently, kprobe_events failure won't be handled properly. Due to calling system() indirectly to write to kprobe_events, it can't be identified whether an error is derived from kprobe or system. // buf = "echo '%c:%s %s' >> /s/k/d/t/kprobe_events" err = system(buf); if (err < 0) { printf("failed to create kprobe .."); return -1; } For example, running ./tracex7 sample in ext4 partition, "echo p:open_ctree open_ctree >> /s/k/d/t/kprobe_events" gets 256 error code system() failure. => The error comes from kprobe, but it's not handled correctly. According to man of system(3), it's return value just passes the termination status of the child shell rather than treating the error as -1. (don't care success) Which means, currently it's not working as desired. (According to the upper code snippet) ex) running ./tracex7 with ext4 env. # Current Output sh: echo: I/O error failed to open event open_ctree # Desired Output failed to create kprobe 'open_ctree' error 'No such file or directory' The problem is, error can't be verified whether from child ps or system. But using write() directly can verify the command failure, and it will treat all error as -1. So I suggest using write() directly to 'kprobe_events' rather than calling system(). Signed-off-by: Daniel T. Lee Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin

bpf, tracex3_user: erase "ARRAY_SIZE" redefined

2018-10-04T14:31:57+00:00

There is a warning when compiling bpf sample programs in sample/bpf: make -C /home/foo/bpf/samples/bpf/../../tools/lib/bpf/ RM='rm -rf' LDFLAGS= srctree=/home/foo/bpf/samples/bpf/../../ O= HOSTCC /home/foo/bpf/samples/bpf/tracex3_user.o /home/foo/bpf/samples/bpf/tracex3_user.c:20:0: warning: "ARRAY_SIZE" redefined #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) In file included from /home/foo/bpf/samples/bpf/tracex3_user.c:18:0: ./tools/testing/selftests/bpf/bpf_util.h:48:0: note: this is the location of the previous definition # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) Signed-off-by: Bo YU Signed-off-by: Daniel Borkmann

samples/bpf: extend test_cgrp2_attach2 test to use per-cpu cgroup storage

2018-10-01T14:18:33+00:00

This commit extends the test_cgrp2_attach2 test to cover per-cpu cgroup storage. Bpf program will use shared and per-cpu cgroup storages simultaneously, so a better coverage of corresponding core code will be achieved. Expected output: $ ./test_cgrp2_attach2 Attached DROP prog. This ping in cgroup /foo should fail... ping: sendmsg: Operation not permitted Attached DROP prog. This ping in cgroup /foo/bar should fail... ping: sendmsg: Operation not permitted Attached PASS prog. This ping in cgroup /foo/bar should pass... Detached PASS from /foo/bar while DROP is attached to /foo. This ping in cgroup /foo/bar should fail... ping: sendmsg: Operation not permitted Attached PASS from /foo/bar and detached DROP from /foo. This ping in cgroup /foo/bar should pass... ### override:PASS ### multi:PASS Signed-off-by: Roman Gushchin Acked-by: Song Liu Cc: Daniel Borkmann Cc: Alexei Starovoitov Signed-off-by: Daniel Borkmann

samples/bpf: fix compilation failure

2018-09-21T20:51:16+00:00

following commit: commit d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") added struct bpf_flow_keys which conflicts with the struct with same name in sockex2_kern.c and sockex3_kern.c similar to commit: commit 534e0e52bc23 ("samples/bpf: fix a compilation failure") we tried the rename it "flow_keys" but it also conflicted with struct having same name in include/net/flow_dissector.h. Hence renaming the struct to "flow_key_record". Also, this commit doesn't fix the compilation error completely because the similar struct is present in sockex3_kern.c. Hence renaming it in both files sockex3_user.c and sockex3_kern.c Signed-off-by: Prashant Bhole Acked-by: Song Liu Signed-off-by: Daniel Borkmann

samples/bpf: fix a compilation failure

2018-09-18T15:50:02+00:00

samples/bpf build failed with the following errors: $ make samples/bpf/ ... HOSTCC samples/bpf/sockex3_user.o /data/users/yhs/work/net-next/samples/bpf/sockex3_user.c:16:8: error: redefinition of ‘struct bpf_flow_keys’ struct bpf_flow_keys { ^ In file included from /data/users/yhs/work/net-next/samples/bpf/sockex3_user.c:4:0: ./usr/include/linux/bpf.h:2338:9: note: originally defined here struct bpf_flow_keys *flow_keys; ^ make[3]: *** [samples/bpf/sockex3_user.o] Error 1 Commit d58e468b1112d ("flow_dissector: implements flow dissector BPF hook") introduced struct bpf_flow_keys in include/uapi/linux/bpf.h and hence caused the naming conflict with samples/bpf/sockex3_user.c. The fix is to rename struct bpf_flow_keys in samples/bpf/sockex3_user.c to flow_keys to avoid the conflict. Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann

samples/bpf: remove duplicated includes

2018-09-18T15:49:33+00:00

Remove duplicated includes. Signed-off-by: YueHaibing Acked-by: Yonghong Song Signed-off-by: Daniel Borkmann

samples/bpf: xdpsock, minor fixes

2018-08-31T23:36:08+00:00

- xsks_map size was fixed to 4, changed it MAX_SOCKS - Remove redundant definition of MAX_SOCKS in xdpsock_user.c - In dump_stats(), add NULL check for xsks[i] Signed-off-by: Prashant Bhole Acked-by: Björn Töpel Signed-off-by: Daniel Borkmann

bpf: add TCP_SAVE_SYN/TCP_SAVED_SYN sample program

2018-08-31T23:36:04+00:00

Sample program which shows TCP_SAVE_SYN/TCP_SAVED_SYN usage example: bpf program which is doing TOS/TCLASS reflection (server would reply with a same TOS/TCLASS as client). Signed-off-by: Nikita V. Shirokov Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann

samples/bpf: add -c/--copy -z/--zero-copy flags to xdpsock

2018-08-29T19:25:53+00:00

The -c/--copy -z/--zero-copy flags enforces either copy or zero-copy mode. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov

samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM

2018-08-16T19:55:32+00:00

It is common XDP practice to unload/deattach the XDP bpf program, when the XDP sample program is Ctrl-C interrupted (SIGINT) or killed (SIGTERM). The samples/bpf programs xdp_redirect_cpu and xdp_rxq_info, forgot to trap signal SIGTERM (which is the default signal used by the kill command). This was discovered by Red Hat QA, which automated scripts depend on killing the XDP sample program after a timeout period. Fixes: fad3917e361b ("samples/bpf: add cpumap sample program xdp_redirect_cpu") Fixes: 0fca931a6f21 ("samples/bpf: program demonstrating access to xdp_rxq_info") Reported-by: Jean-Tsung Hsiao Signed-off-by: Jesper Dangaard Brouer Acked-by: Yonghong Song Signed-off-by: Daniel Borkmann