linux.git/tools/bpf/bpftool/common.c, branch v4.20

tools: bpftool: pass an argument to silence open_obj_pinned()

2018-11-09T07:20:52+00:00

Function open_obj_pinned() prints error messages when it fails to open a
link in the BPF virtual file system. However, in some occasions it is
not desirable to print an error, for example when we parse all links
under the bpffs root, and the error is due to some paths actually being
symbolic links.

Example output:

    # ls -l /sys/fs/bpf/
    lrwxrwxrwx 1 root root 0 Oct 18 19:00 ip -> /sys/fs/bpf/tc/
    drwx------ 3 root root 0 Oct 18 19:00 tc
    lrwxrwxrwx 1 root root 0 Oct 18 19:00 xdp -> /sys/fs/bpf/tc/

    # bpftool --bpffs prog show
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    Error: bpf obj get (/sys/fs/bpf): Permission denied

    # strace -e bpf bpftool --bpffs prog show
    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/ip", bpf_fd=0}, 72) = -1 EACCES (Permission denied)
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/xdp", bpf_fd=0}, 72) = -1 EACCES (Permission denied)
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    ...

To fix it, pass a bool as a second argument to the function, and prevent
it from printing an error when the argument is set to true.

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

tools: bpftool: prevent infinite loop in get_fdinfo()

2018-11-09T07:20:52+00:00

Function getline() returns -1 on failure to read a line, thus creating
an infinite loop in get_fdinfo() if the key is not found. Fix it by
calling the function only as long as we get a strictly positive return
value.

Found by copying the code for a key which is not always present...

Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")
Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

tools: bpftool: use 4 context mode for the NFP disasm

2018-10-18T20:16:02+00:00

The nfp driver is currently always JITing the BPF for 4 context/thread
mode of the NFP flow processors.  Tell this to the disassembler,
otherwise some registers may be incorrectly decoded.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Jiong Wang 
Signed-off-by: Daniel Borkmann

tools: bpftool: add map create command

2018-10-15T23:39:21+00:00

Add a way of creating maps from user space.  The command takes
as parameters most of the attributes of the map creation system
call command.  After map is created its pinned to bpffs.  This makes
it possible to easily and dynamically (without rebuilding programs)
test various corner cases related to map creation.

Map type names are taken from bpftool's array used for printing.
In general these days we try to make use of libbpf type names, but
there are no map type names in libbpf as of today.

As with most features I add the motivation is testing (offloads) :)

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Signed-off-by: Alexei Starovoitov

Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net

2018-07-25T02:21:58+00:00

tools/bpftool: Fix segfault case regarding 'pin' arguments

2018-07-20T08:16:54+00:00

Arguments of 'pin' subcommand should be checked
at the very beginning of do_pin_any().
Otherwise segfault errors can occur when using
'map pin' or 'prog pin' commands, so fix it.

  # bpftool prog pin id
  Segmentation fault

Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")
Reviewed-by: Jakub Kicinski 
Reported-by: Taehee Yoo 
Signed-off-by: Taeung Song 
Signed-off-by: Daniel Borkmann

tools: bpftool: drop unnecessary Author comments

2018-06-30T23:01:50+00:00

Drop my author comments, those are from the early days of
bpftool and make little sense in tree, where we have quite
a few people contributing and git to attribute the work.

While at it bump some copyrights.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Signed-off-by: Daniel Borkmann

tools: bpftool: add simple perf event output reader

2018-05-04T21:41:04+00:00

Users of BPF sooner or later discover perf_event_output() helpers
and BPF_MAP_TYPE_PERF_EVENT_ARRAY.  Dumping this array type is
not possible, however, we can add simple reading of perf events.
Create a new event_pipe subcommand for maps, this sub command
will only work with BPF_MAP_TYPE_PERF_EVENT_ARRAY maps.

Parts of the code from samples/bpf/trace_output_user.c.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Acked-by: Alexei Starovoitov 
Signed-off-by: Daniel Borkmann

tools: bpftool: move get_possible_cpus() to common code

2018-05-04T21:41:04+00:00

Move the get_possible_cpus() function to shared code.  No functional
changes.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Reviewed-by: Jiong Wang 
Signed-off-by: Daniel Borkmann

tools: bpftool: fix compilation with older headers

2018-03-06T21:51:00+00:00

Compilation of bpftool on a distro that lacks eBPF support in the installed
kernel headers fails with:

common.c: In function ‘is_bpffs’:
common.c:96:40: error: ‘BPF_FS_MAGIC’ undeclared (first use in this function)
  return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
                                        ^
Fix this the same way it is already in tools/lib/bpf/libbpf.c and
tools/lib/api/fs/fs.c.

Signed-off-by: Jiri Benc 
Signed-off-by: Daniel Borkmann