linux/tools/bpf/bpftool
Sahil Siddiq 478a535ae5 bpftool: Mount bpffs on provided dir instead of parent dir
When pinning programs/objects under PATH (eg: during "bpftool prog
loadall") the bpffs is mounted on the parent dir of PATH in the
following situations:
- the given dir exists but it is not bpffs.
- the given dir doesn't exist and the parent dir is not bpffs.

Mounting on the parent dir can also have the unintentional side-
effect of hiding other files located under the parent dir.

If the given dir exists but is not bpffs, then the bpffs should
be mounted on the given dir and not its parent dir.

Similarly, if the given dir doesn't exist and its parent dir is not
bpffs, then the given dir should be created and the bpffs should be
mounted on this new dir.

Fixes: 2a36c26fe3 ("bpftool: Support bpffs mountpoint as pin path for prog loadall")
Signed-off-by: Sahil Siddiq <icegambit91@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/2da44d24-74ae-a564-1764-afccf395eeec@isovalent.com/T/#t
Link: https://lore.kernel.org/bpf/20240404192219.52373-1-icegambit91@gmail.com

Closes: https://github.com/libbpf/bpftool/issues/100

Changes since v1:
 - Split "mount_bpffs_for_pin" into two functions.
   This is done to improve maintainability and readability.

Changes since v2:
- mount_bpffs_for_pin: rename to "create_and_mount_bpffs_dir".
- mount_bpffs_given_file: rename to "mount_bpffs_given_file".
- create_and_mount_bpffs_dir:
  - introduce "dir_exists" boolean.
  - remove new dir if "mnt_fs" fails.
- improve error handling and error messages.

Changes since v3:
- Rectify function name.
- Improve error messages and formatting.
- mount_bpffs_for_file:
  - Check if dir exists before block_mount check.

Changes since v4:
- Use strdup instead of strcpy.
- create_and_mount_bpffs_dir:
  - Use S_IRWXU instead of 0700.
- Improve error handling and formatting.
2024-04-04 15:37:12 -07:00
..
bash-completion bpftool: Add support for cgroup unix socket address hooks 2023-10-11 17:27:55 -07:00
Documentation bpftool: Clean-up typos, punctuation, list formatting in docs 2024-04-02 15:50:23 +02:00
skeleton bpftool: Fix missing pids during link show 2024-03-14 13:37:43 -07:00
.gitignore bpftool: Fix SPDX tag for Makefiles and .gitignore 2021-11-10 09:00:52 -08:00
btf_dumper.c bpftool: Fix printing of pointer value 2023-10-19 16:29:36 +02:00
btf.c bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() 2023-02-16 15:32:45 -08:00
cfg.c bpftool: Support printing opcodes and source file references in CFG 2023-04-05 21:27:27 -07:00
cfg.h bpftool: Support printing opcodes and source file references in CFG 2023-04-05 21:27:27 -07:00
cgroup.c bpftool: Add support for cgroup unix socket address hooks 2023-10-11 17:27:55 -07:00
common.c bpftool: Mount bpffs on provided dir instead of parent dir 2024-04-04 15:37:12 -07:00
feature.c bpf: improve error message for unsupported helper 2024-03-28 18:30:53 -07:00
gen.c bpftool: Use __typeof__() instead of typeof() in BPF skeleton 2024-04-02 16:20:49 +02:00
iter.c bpftool: Mount bpffs on provided dir instead of parent dir 2024-04-04 15:37:12 -07:00
jit_disasm.c bpftool: Fix spelling mistake "disasembler" -> "disassembler" 2022-10-26 18:20:22 -07:00
json_writer.c tools: bpftool: json: Fix backslash escape typo in jsonw_puts 2023-03-29 09:48:45 -07:00
json_writer.h tools: bpftool: json: Fix backslash escape typo in jsonw_puts 2023-03-29 09:48:45 -07:00
link.c bpftool: Display cookie for kprobe multi link 2024-01-23 16:05:28 -08:00
main.c bpftool: clean-up usage of libbpf_get_error() 2022-11-20 16:17:46 -08:00
main.h bpftool: Mount bpffs on provided dir instead of parent dir 2024-04-04 15:37:12 -07:00
Makefile bpftool: Clean up HOST_CFLAGS, HOST_LDFLAGS for bootstrap bpftool 2024-03-20 23:33:49 -07:00
map_perf_ring.c bpftool: Fix error message of strerror 2022-09-30 15:40:46 -07:00
map.c bpftool: Recognize arena map type 2024-03-11 15:37:24 -07:00
net.c bpftool: Extend net dump with netkit progs 2023-10-24 16:07:32 -07:00
netlink_dumper.c bpftool: Use consistent include paths for libbpf 2020-01-20 16:37:45 -08:00
netlink_dumper.h bpftool: Extend net dump with tcx progs 2023-07-19 10:07:28 -07:00
perf.c bpftool: fix perf help message 2023-08-11 20:54:29 -07:00
pids.c bpftool: Enable libbpf logs when loading pid_iter in debug mode 2024-03-19 23:12:22 -07:00
prog.c bpftool: Mount bpffs on provided dir instead of parent dir 2024-04-04 15:37:12 -07:00
struct_ops.c bpftool: Mount bpffs on provided dir instead of parent dir 2024-04-04 15:37:12 -07:00
tracelog.c bpftool, musl compat: Replace sys/fcntl.h by fcntl.h 2022-04-25 23:24:28 +02:00
xlated_dumper.c bpftool: Dump the kernel symbol's module name 2023-07-11 20:07:50 -07:00
xlated_dumper.h bpftool: Dump the kernel symbol's module name 2023-07-11 20:07:50 -07:00