generic_permission (9) - Linux Manuals

generic_permission: check for access rights on a Posix-like filesystem

Command to display generic_permission manual in Linux: $ man 9 generic_permission

NAME

generic_permission - check for access rights on a Posix-like filesystem

SYNOPSIS

int generic_permission(struct inode * inode, int mask);

ARGUMENTS

inode

: inode to check access rights for

mask

: right to check for (MAY_READ, MAY_WRITE, MAY_EXEC, ...)

DESCRIPTION

Used to check for read/write/execute permissions on a file. We use "fsuid" for this, letting us set arbitrary permissions for filesystem access without changing the "normal" uids which are used for other things.

generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk request cannot be satisfied (eg. requires blocking or too much complexity). It would then be called again in ref-walk mode.