On 04/04/2024 20:22, Sahil Siddiq wrote: > 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. > > Link: https://lore.kernel.org/bpf/2da44d24-74ae-a564-1764-afccf395eeec@xxxxxxxxxxxxx/T/#t > Closes: https://github.com/libbpf/bpftool/issues/100 > Fixes: 2a36c26fe3b8 ("bpftool: Support bpffs mountpoint as pin path for prog loadall") > > 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. > > Signed-off-by: Sahil Siddiq <icegambit91@xxxxxxxxx> Tested-by: Quentin Monnet <qmo@xxxxxxxxxx> Reviewed-by: Quentin Monnet <qmo@xxxxxxxxxx> Thank you!
