The branch main has been updated by dchagin: URL: https://cgit.FreeBSD.org/src/commit/?id=07c0b6e535c5c5bdbbb562a04e21a1a4d039b942
commit 07c0b6e535c5c5bdbbb562a04e21a1a4d039b942 Author: Dmitry Chagin <[email protected]> AuthorDate: 2023-05-29 08:19:41 +0000 Commit: Dmitry Chagin <[email protected]> CommitDate: 2023-05-29 08:19:41 +0000 vfs: Retire kern_alternate_path() as unused anymore From now a non-native ABI should use pwd_altroot() ability to tell to the namei() its root directory to dynamically reroots lookups. Differential Revision: https://reviews.freebsd.org/D40093 MFC after: 2 month --- sys/kern/vfs_lookup.c | 114 -------------------------------------------------- sys/sys/syscallsubr.h | 2 - 2 files changed, 116 deletions(-) diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c index 593e1e487c6f..c813296b4931 100644 --- a/sys/kern/vfs_lookup.c +++ b/sys/kern/vfs_lookup.c @@ -1597,117 +1597,3 @@ NDVALIDATE_impl(struct nameidata *ndp, int line) } #endif - -/* - * Determine if there is a suitable alternate filename under the specified - * prefix for the specified path. If the create flag is set, then the - * alternate prefix will be used so long as the parent directory exists. - * This is used by the various compatibility ABIs so that Linux binaries prefer - * files under /compat/linux for example. The chosen path (whether under - * the prefix or under /) is returned in a kernel malloc'd buffer pointed - * to by pathbuf. The caller is responsible for free'ing the buffer from - * the M_TEMP bucket if one is returned. - */ -int -kern_alternate_path(const char *prefix, const char *path, enum uio_seg pathseg, - char **pathbuf, int create, int dirfd) -{ - struct nameidata nd, ndroot; - char *ptr, *buf, *cp; - size_t len, sz; - int error; - - buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK); - *pathbuf = buf; - - /* Copy the prefix into the new pathname as a starting point. */ - len = strlcpy(buf, prefix, MAXPATHLEN); - if (len >= MAXPATHLEN) { - *pathbuf = NULL; - free(buf, M_TEMP); - return (EINVAL); - } - sz = MAXPATHLEN - len; - ptr = buf + len; - - /* Append the filename to the prefix. */ - if (pathseg == UIO_SYSSPACE) - error = copystr(path, ptr, sz, &len); - else - error = copyinstr(path, ptr, sz, &len); - - if (error) { - *pathbuf = NULL; - free(buf, M_TEMP); - return (error); - } - - /* Only use a prefix with absolute pathnames. */ - if (*ptr != '/') { - error = EINVAL; - goto keeporig; - } - - if (dirfd != AT_FDCWD) { - /* - * We want the original because the "prefix" is - * included in the already opened dirfd. - */ - bcopy(ptr, buf, len); - return (0); - } - - /* - * We know that there is a / somewhere in this pathname. - * Search backwards for it, to find the file's parent dir - * to see if it exists in the alternate tree. If it does, - * and we want to create a file (cflag is set). We don't - * need to worry about the root comparison in this case. - */ - - if (create) { - for (cp = &ptr[len] - 1; *cp != '/'; cp--); - *cp = '\0'; - - NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, buf); - error = namei(&nd); - *cp = '/'; - if (error != 0) - goto keeporig; - } else { - NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, buf); - - error = namei(&nd); - if (error != 0) - goto keeporig; - - /* - * We now compare the vnode of the prefix to the one - * vnode asked. If they resolve to be the same, then we - * ignore the match so that the real root gets used. - * This avoids the problem of traversing "../.." to find the - * root directory and never finding it, because "/" resolves - * to the emulation root directory. This is expensive :-( - */ - NDINIT(&ndroot, LOOKUP, FOLLOW, UIO_SYSSPACE, prefix); - - /* We shouldn't ever get an error from this namei(). */ - error = namei(&ndroot); - if (error == 0) { - if (nd.ni_vp == ndroot.ni_vp) - error = ENOENT; - - NDFREE_PNBUF(&ndroot); - vrele(ndroot.ni_vp); - } - } - - NDFREE_PNBUF(&nd); - vrele(nd.ni_vp); - -keeporig: - /* If there was an error, use the original path name. */ - if (error) - bcopy(ptr, buf, len); - return (error); -} diff --git a/sys/sys/syscallsubr.h b/sys/sys/syscallsubr.h index 9486135b9ce2..64f1b16f92b9 100644 --- a/sys/sys/syscallsubr.h +++ b/sys/sys/syscallsubr.h @@ -94,8 +94,6 @@ int kern_accessat(struct thread *td, int fd, const char *path, enum uio_seg pathseg, int flags, int mode); int kern_adjtime(struct thread *td, struct timeval *delta, struct timeval *olddelta); -int kern_alternate_path(const char *prefix, const char *path, - enum uio_seg pathseg, char **pathbuf, int create, int dirfd); int kern_bindat(struct thread *td, int dirfd, int fd, struct sockaddr *sa); int kern_break(struct thread *td, uintptr_t *addr); int kern_cap_ioctls_limit(struct thread *td, int fd, u_long *cmds,
