Re: [PATCH 1/3] fs_parser: handle parameters that can be empty and don't have a value
From: Christian Brauner <brauner@kernel.org>
Date: 2024-03-01 13:31:54
Also in:
linux-fsdevel, linux-unionfs, lkml
On Thu, Feb 29, 2024 at 04:30:08PM +0000, Luis Henriques wrote:
quoted hunk ↗ jump to hunk
Currently, only parameters that have the fs_parameter_spec 'type' set to NULL are handled as 'flag' types. However, parameters that have the 'fs_param_can_be_empty' flag set and their value is NULL should also be handled as 'flag' type, as their type is set to 'fs_value_is_flag'. Signed-off-by: Luis Henriques <redacted> --- fs/fs_parser.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/fs/fs_parser.c b/fs/fs_parser.c index edb3712dcfa5..53f6cb98a3e0 100644 --- a/fs/fs_parser.c +++ b/fs/fs_parser.c@@ -119,7 +119,8 @@ int __fs_parse(struct p_log *log, /* Try to turn the type we were given into the type desired by the * parameter and give an error if we can't. */ - if (is_flag(p)) { + if (is_flag(p) || + (!param->string && (p->flags & fs_param_can_be_empty))) { if (param->type != fs_value_is_flag) return inval_plog(log, "Unexpected value for '%s'", param->key);
If the parameter was derived from FSCONFIG_SET_STRING in fsconfig() then param->string is guaranteed to not be NULL. So really this is only about: FSCONFIG_SET_FD FSCONFIG_SET_BINARY FSCONFIG_SET_PATH FSCONFIG_SET_PATH_EMPTY and those values being used without a value. What filesystem does this? I don't see any. The tempting thing to do here is to to just remove fs_param_can_be_empty from every helper that isn't fs_param_is_string() until we actually have a filesystem that wants to use any of the above as flags. Will lose a lot of code that isn't currently used.