| Message ID | 20121213112342.720ddc6d@notabene.brown (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Dec 13, 2012 at 11:23:42AM +1100, NeilBrown wrote: > > The is_subdirectory() function checks if a given 'child' is a subdirectory > of the given 'parent'. > However it always fails if 'parent' == "/" (because 'child' doesn't begin > with 'parent' followed by "/"). > > So change is_subdirectory() to special-case "/". Might be slightly more elegant to deal with this as a case of a parent directory with a terminating "/" rather than as a special case, and that might make this a little more robust. E.g.: size_t l = strlen(parent); while (l && parent[l-1] == '/') l--; return (l <= strlen(child)) && strncmp(parent, child, l) == 0 && (child[l] == '/' || child[l] == '\0'); ? --b. > > subexport() also tests if one directory is a subdirectory of the > other, and contains the same bug. So change it to use is_subdirectory(). > > Finally, move is_subdirectory() and related path_matches() and > export_matches() earlier in the file to avoid a forward-reference. > > This patch fixes a bug wherein if you export "/" with 'crossmnt', the > crossmnt flag is ineffective and you can only access the root > filesystem, not any descendants. > > Signed-off-by: NeilBrown <neilb@suse.de> > > diff --git a/utils/mountd/cache.c b/utils/mountd/cache.c > index 3853bb6..45012be 100644 > --- a/utils/mountd/cache.c > +++ b/utils/mountd/cache.c > @@ -343,6 +343,30 @@ static char *next_mnt(void **v, char *p) > return me->mnt_dir; > } > > +static int is_subdirectory(char *child, char *parent) > +{ > + size_t l = strlen(parent); > + > + if (strcmp(parent, "/") == 0) > + return 1; > + > + return strcmp(child, parent) == 0 > + || (strncmp(child, parent, l) == 0 && child[l] == '/'); > +} > + > +static int path_matches(nfs_export *exp, char *path) > +{ > + if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) > + return is_subdirectory(path, exp->m_export.e_path); > + return strcmp(path, exp->m_export.e_path) == 0; > +} > + > +static int > +export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) > +{ > + return path_matches(exp, path) && client_matches(exp, dom, ai); > +} > + > /* True iff e1 is a child of e2 and e2 has crossmnt set: */ > static bool subexport(struct exportent *e1, struct exportent *e2) > { > @@ -350,8 +374,7 @@ static bool subexport(struct exportent *e1, struct exportent *e2) > size_t l2 = strlen(p2); > > return e2->e_flags & NFSEXP_CROSSMOUNT > - && strncmp(p1, p2, l2) == 0 > - && p1[l2] == '/'; > + && is_subdirectory(p1, p2); > } > > struct parsed_fsid { > @@ -752,27 +775,6 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex > return qword_eol(f); > } > > -static int is_subdirectory(char *child, char *parent) > -{ > - size_t l = strlen(parent); > - > - return strcmp(child, parent) == 0 > - || (strncmp(child, parent, l) == 0 && child[l] == '/'); > -} > - > -static int path_matches(nfs_export *exp, char *path) > -{ > - if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) > - return is_subdirectory(path, exp->m_export.e_path); > - return strcmp(path, exp->m_export.e_path) == 0; > -} > - > -static int > -export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) > -{ > - return path_matches(exp, path) && client_matches(exp, dom, ai); > -} > - > static nfs_export * > lookup_export(char *dom, char *path, struct addrinfo *ai) > { -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/12/12 19:23, NeilBrown wrote: > > The is_subdirectory() function checks if a given 'child' is a subdirectory > of the given 'parent'. > However it always fails if 'parent' == "/" (because 'child' doesn't begin > with 'parent' followed by "/"). > > So change is_subdirectory() to special-case "/". > > subexport() also tests if one directory is a subdirectory of the > other, and contains the same bug. So change it to use is_subdirectory(). > > Finally, move is_subdirectory() and related path_matches() and > export_matches() earlier in the file to avoid a forward-reference. > > This patch fixes a bug wherein if you export "/" with 'crossmnt', the > crossmnt flag is ineffective and you can only access the root > filesystem, not any descendants. > > Signed-off-by: NeilBrown <neilb@suse.de> Committed... steved. > > diff --git a/utils/mountd/cache.c b/utils/mountd/cache.c > index 3853bb6..45012be 100644 > --- a/utils/mountd/cache.c > +++ b/utils/mountd/cache.c > @@ -343,6 +343,30 @@ static char *next_mnt(void **v, char *p) > return me->mnt_dir; > } > > +static int is_subdirectory(char *child, char *parent) > +{ > + size_t l = strlen(parent); > + > + if (strcmp(parent, "/") == 0) > + return 1; > + > + return strcmp(child, parent) == 0 > + || (strncmp(child, parent, l) == 0 && child[l] == '/'); > +} > + > +static int path_matches(nfs_export *exp, char *path) > +{ > + if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) > + return is_subdirectory(path, exp->m_export.e_path); > + return strcmp(path, exp->m_export.e_path) == 0; > +} > + > +static int > +export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) > +{ > + return path_matches(exp, path) && client_matches(exp, dom, ai); > +} > + > /* True iff e1 is a child of e2 and e2 has crossmnt set: */ > static bool subexport(struct exportent *e1, struct exportent *e2) > { > @@ -350,8 +374,7 @@ static bool subexport(struct exportent *e1, struct exportent *e2) > size_t l2 = strlen(p2); > > return e2->e_flags & NFSEXP_CROSSMOUNT > - && strncmp(p1, p2, l2) == 0 > - && p1[l2] == '/'; > + && is_subdirectory(p1, p2); > } > > struct parsed_fsid { > @@ -752,27 +775,6 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex > return qword_eol(f); > } > > -static int is_subdirectory(char *child, char *parent) > -{ > - size_t l = strlen(parent); > - > - return strcmp(child, parent) == 0 > - || (strncmp(child, parent, l) == 0 && child[l] == '/'); > -} > - > -static int path_matches(nfs_export *exp, char *path) > -{ > - if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) > - return is_subdirectory(path, exp->m_export.e_path); > - return strcmp(path, exp->m_export.e_path) == 0; > -} > - > -static int > -export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) > -{ > - return path_matches(exp, path) && client_matches(exp, dom, ai); > -} > - > static nfs_export * > lookup_export(char *dom, char *path, struct addrinfo *ai) > { > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/utils/mountd/cache.c b/utils/mountd/cache.c index 3853bb6..45012be 100644 --- a/utils/mountd/cache.c +++ b/utils/mountd/cache.c @@ -343,6 +343,30 @@ static char *next_mnt(void **v, char *p) return me->mnt_dir; } +static int is_subdirectory(char *child, char *parent) +{ + size_t l = strlen(parent); + + if (strcmp(parent, "/") == 0) + return 1; + + return strcmp(child, parent) == 0 + || (strncmp(child, parent, l) == 0 && child[l] == '/'); +} + +static int path_matches(nfs_export *exp, char *path) +{ + if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) + return is_subdirectory(path, exp->m_export.e_path); + return strcmp(path, exp->m_export.e_path) == 0; +} + +static int +export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) +{ + return path_matches(exp, path) && client_matches(exp, dom, ai); +} + /* True iff e1 is a child of e2 and e2 has crossmnt set: */ static bool subexport(struct exportent *e1, struct exportent *e2) { @@ -350,8 +374,7 @@ static bool subexport(struct exportent *e1, struct exportent *e2) size_t l2 = strlen(p2); return e2->e_flags & NFSEXP_CROSSMOUNT - && strncmp(p1, p2, l2) == 0 - && p1[l2] == '/'; + && is_subdirectory(p1, p2); } struct parsed_fsid { @@ -752,27 +775,6 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex return qword_eol(f); } -static int is_subdirectory(char *child, char *parent) -{ - size_t l = strlen(parent); - - return strcmp(child, parent) == 0 - || (strncmp(child, parent, l) == 0 && child[l] == '/'); -} - -static int path_matches(nfs_export *exp, char *path) -{ - if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) - return is_subdirectory(path, exp->m_export.e_path); - return strcmp(path, exp->m_export.e_path) == 0; -} - -static int -export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai) -{ - return path_matches(exp, path) && client_matches(exp, dom, ai); -} - static nfs_export * lookup_export(char *dom, char *path, struct addrinfo *ai) {
The is_subdirectory() function checks if a given 'child' is a subdirectory of the given 'parent'. However it always fails if 'parent' == "/" (because 'child' doesn't begin with 'parent' followed by "/"). So change is_subdirectory() to special-case "/". subexport() also tests if one directory is a subdirectory of the other, and contains the same bug. So change it to use is_subdirectory(). Finally, move is_subdirectory() and related path_matches() and export_matches() earlier in the file to avoid a forward-reference. This patch fixes a bug wherein if you export "/" with 'crossmnt', the crossmnt flag is ineffective and you can only access the root filesystem, not any descendants. Signed-off-by: NeilBrown <neilb@suse.de>