Jiri Olsa 752bcf80f5 bpftool: Fix prog dump by tag ... Lance reported an issue with bpftool not being able to dump program if there are more programs loaded and you want to dump any but the first program, like: # bpftool prog 28: kprobe name trace_req_start tag 1dfc28ba8b3dd597 gpl loaded_at 2019-01-18T17:02:40+1100 uid 0 xlated 112B jited 109B memlock 4096B map_ids 13 29: kprobe name trace_req_compl tag 5b6a5ecc6030a683 gpl loaded_at 2019-01-18T17:02:40+1100 uid 0 xlated 928B jited 575B memlock 4096B map_ids 13,14 # bpftool prog dum jited tag 1dfc28ba8b3dd597 0: push %rbp 1: mov %rsp,%rbp ... # bpftool prog dum jited tag 5b6a5ecc6030a683 Error: can't get prog info (29): Bad address The problem is in the prog_fd_by_tag function not cleaning the struct bpf_prog_info before another request, so the previous program length is still in there and kernel assumes it needs to dump the program, which fails because there's no user pointer set. Moving the struct bpf_prog_info declaration into the loop, so it gets cleaned before each query. Fixes: 71bb428fe2 ("tools: bpf: add bpftool") Reported-by: Lance Digby <ldigby@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>		2019-01-23 09:52:12 +01:00
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bpftool	bpftool: Fix prog dump by tag	2019-01-23 09:52:12 +01:00
.gitignore	tools/bpftool: ignore build products	2018-07-26 02:50:26 +02:00
bpf_asm.c
bpf_dbg.c	bpf: fix uninitialized variable in bpf tools	2018-04-26 22:23:02 +02:00
bpf_exp.l	bpf: fix cbpf parser bug for octal numbers	2018-06-03 07:46:55 -07:00
bpf_exp.y
bpf_jit_disasm.c	tools/bpf_jit_disasm: silence a static checker warning	2018-01-18 22:15:37 +01:00
Makefile	bpf: fix for lex/yacc build error with gcc-5	2018-04-25 23:27:46 +02:00
Makefile.helpers	tools: bpf: build and install man page for eBPF helpers from bpftool/	2018-07-12 18:55:53 +02:00