Konstantin Belousov
2018-Sep-21 13:48 UTC
Constraints in libmap(32).conf do not work as expected, possible bug in rtld-elf
On Tue, Sep 11, 2018 at 10:47:58PM +0200, Andreas Longwitz wrote:> Thanks very much for answer ! > > Now I use the following libmap32.conf: > > ## php52 > [/usr/local/php52/lib/php/20060613/mysql.so] > /usr/local/lib/mysql /usr/local/lib32/mysql > [/usr/local/php52/] > /usr/local/lib /usr/local/lib32 > > > I am having problem understanding what do you mean by step1/step2. The > > refobj reference that you cache in the patch, comes into load_object() > > as the pointer to the object which initiate the load_object() call. It > > is NULL for preloaded objects, otherwise it is not. > > So, could you, please, explain where does it get passed as NULL in your > > case ? > > Ok, I try to explain better: > > step1 means: call of lm_find() in rtld.c (line 1500) and first argument > is refobj->path, which is used in libmap.c to find the correct entry in > the lmp_list. > > step2 means: call of lm_findn() in rtld.c (line 2834) when called from > search_library_path(). In this case the first argument is NULL and in > libmap.c this means "$DEFAULT" entry in the lmp_list. Please notice that > after reading libmap32.conf in lm_init() the entry $DEFAULT in the > lmp_list does not exist, when all mappings are defined with constraints.Can you try this instead ? diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c index dfd0388478f..83d5e28e287 100644 --- a/libexec/rtld-elf/rtld.c +++ b/libexec/rtld-elf/rtld.c @@ -125,7 +125,7 @@ static void objlist_remove(Objlist *, Obj_Entry *); static int open_binary_fd(const char *argv0, bool search_in_path); static int parse_args(char* argv[], int argc, bool *use_pathp, int *fdp); static int parse_integer(const char *); -static void *path_enumerate(const char *, path_enum_proc, void *); +static void *path_enumerate(const char *, path_enum_proc, const char *, void *); static void print_usage(const char *argv0); static void release_object(Obj_Entry *); static int relocate_object_dag(Obj_Entry *root, bool bind_now, @@ -140,7 +140,8 @@ static int rtld_dirname(const char *, char *); static int rtld_dirname_abs(const char *, char *); static void *rtld_dlopen(const char *name, int fd, int mode); static void rtld_exit(void); -static char *search_library_path(const char *, const char *, int *); +static char *search_library_path(const char *, const char *, const char *, + int *); static char *search_library_pathfds(const char *, const char *, int *); static const void **get_program_var_addr(const char *, RtldLockState *); static void set_program_var(const char *, const void *); @@ -1576,8 +1577,7 @@ gnu_hash(const char *s) static char * find_library(const char *xname, const Obj_Entry *refobj, int *fdp) { - char *pathname; - char *name; + char *name, *pathname, *refobj_path; bool nodeflib, objgiven; objgiven = refobj != NULL; @@ -1597,6 +1597,7 @@ find_library(const char *xname, const Obj_Entry *refobj, int *fdp) } dbg(" Searching for \"%s\"", name); + refobj_path = objgiven ? refobj->path : NULL; /* * If refobj->rpath != NULL, then refobj->runpath is NULL. Fall @@ -1605,52 +1606,61 @@ find_library(const char *xname, const Obj_Entry *refobj, int *fdp) * nodeflib. */ if (objgiven && refobj->rpath != NULL && ld_library_path_rpath) { - pathname = search_library_path(name, ld_library_path, fdp); + pathname = search_library_path(name, ld_library_path, + refobj_path, fdp); if (pathname != NULL) return (pathname); if (refobj != NULL) { - pathname = search_library_path(name, refobj->rpath, fdp); + pathname = search_library_path(name, refobj->rpath, + refobj_path, fdp); if (pathname != NULL) return (pathname); } pathname = search_library_pathfds(name, ld_library_dirs, fdp); if (pathname != NULL) return (pathname); - pathname = search_library_path(name, gethints(false), fdp); + pathname = search_library_path(name, gethints(false), + refobj_path, fdp); if (pathname != NULL) return (pathname); - pathname = search_library_path(name, ld_standard_library_path, fdp); + pathname = search_library_path(name, ld_standard_library_path, + refobj_path, fdp); if (pathname != NULL) return (pathname); } else { nodeflib = objgiven ? refobj->z_nodeflib : false; if (objgiven) { - pathname = search_library_path(name, refobj->rpath, fdp); + pathname = search_library_path(name, refobj->rpath, + refobj->path, fdp); if (pathname != NULL) return (pathname); } if (objgiven && refobj->runpath == NULL && refobj != obj_main) { - pathname = search_library_path(name, obj_main->rpath, fdp); + pathname = search_library_path(name, obj_main->rpath, + refobj_path, fdp); if (pathname != NULL) return (pathname); } - pathname = search_library_path(name, ld_library_path, fdp); + pathname = search_library_path(name, ld_library_path, + refobj_path, fdp); if (pathname != NULL) return (pathname); if (objgiven) { - pathname = search_library_path(name, refobj->runpath, fdp); + pathname = search_library_path(name, refobj->runpath, + refobj_path, fdp); if (pathname != NULL) return (pathname); } pathname = search_library_pathfds(name, ld_library_dirs, fdp); if (pathname != NULL) return (pathname); - pathname = search_library_path(name, gethints(nodeflib), fdp); + pathname = search_library_path(name, gethints(nodeflib), + refobj_path, fdp); if (pathname != NULL) return (pathname); if (objgiven && !nodeflib) { pathname = search_library_path(name, - ld_standard_library_path, fdp); + ld_standard_library_path, refobj_path, fdp); if (pathname != NULL) return (pathname); } @@ -1845,8 +1855,9 @@ gethints(bool nostdlib) hargs.request = RTLD_DI_SERINFOSIZE; hargs.serinfo = &hmeta; - path_enumerate(ld_standard_library_path, fill_search_info, &sargs); - path_enumerate(hints, fill_search_info, &hargs); + path_enumerate(ld_standard_library_path, fill_search_info, NULL, + &sargs); + path_enumerate(hints, fill_search_info, NULL, &hargs); SLPinfo = xmalloc(smeta.dls_size); hintinfo = xmalloc(hmeta.dls_size); @@ -1864,8 +1875,9 @@ gethints(bool nostdlib) hargs.serpath = &hintinfo->dls_serpath[0]; hargs.strspace = (char *)&hintinfo->dls_serpath[hmeta.dls_cnt]; - path_enumerate(ld_standard_library_path, fill_search_info, &sargs); - path_enumerate(hints, fill_search_info, &hargs); + path_enumerate(ld_standard_library_path, fill_search_info, NULL, + &sargs); + path_enumerate(hints, fill_search_info, NULL, &hargs); /* * Now calculate the difference between two sets, by excluding @@ -2974,7 +2986,8 @@ rtld_exit(void) * callback on the result. */ static void * -path_enumerate(const char *path, path_enum_proc callback, void *arg) +path_enumerate(const char *path, path_enum_proc callback, + const char *refobj_path, void *arg) { const char *trans; if (path == NULL) @@ -2986,7 +2999,7 @@ path_enumerate(const char *path, path_enum_proc callback, void *arg) char *res; len = strcspn(path, ":;"); - trans = lm_findn(NULL, path, len); + trans = lm_findn(refobj_path, path, len); if (trans) res = callback(trans, strlen(trans), arg); else @@ -3045,7 +3058,8 @@ try_library_path(const char *dir, size_t dirlen, void *param) } static char * -search_library_path(const char *name, const char *path, int *fdp) +search_library_path(const char *name, const char *path, + const char *refobj_path, int *fdp) { char *p; struct try_library_args arg; @@ -3059,7 +3073,7 @@ search_library_path(const char *name, const char *path, int *fdp) arg.buflen = PATH_MAX; arg.fd = -1; - p = path_enumerate(path, try_library_path, &arg); + p = path_enumerate(path, try_library_path, refobj_path, &arg); *fdp = arg.fd; free(arg.buffer); @@ -3776,12 +3790,12 @@ do_search_info(const Obj_Entry *obj, int request, struct dl_serinfo *info) _info.dls_size = __offsetof(struct dl_serinfo, dls_serpath); _info.dls_cnt = 0; - path_enumerate(obj->rpath, fill_search_info, &args); - path_enumerate(ld_library_path, fill_search_info, &args); - path_enumerate(obj->runpath, fill_search_info, &args); - path_enumerate(gethints(obj->z_nodeflib), fill_search_info, &args); + path_enumerate(obj->rpath, fill_search_info, NULL, &args); + path_enumerate(ld_library_path, fill_search_info, NULL, &args); + path_enumerate(obj->runpath, fill_search_info, NULL, &args); + path_enumerate(gethints(obj->z_nodeflib), fill_search_info, NULL, &args); if (!obj->z_nodeflib) - path_enumerate(ld_standard_library_path, fill_search_info, &args); + path_enumerate(ld_standard_library_path, fill_search_info, NULL, &args); if (request == RTLD_DI_SERINFOSIZE) { @@ -3801,25 +3815,25 @@ do_search_info(const Obj_Entry *obj, int request, struct dl_serinfo *info) args.strspace = (char *)&info->dls_serpath[_info.dls_cnt]; args.flags = LA_SER_RUNPATH; - if (path_enumerate(obj->rpath, fill_search_info, &args) != NULL) + if (path_enumerate(obj->rpath, fill_search_info, NULL, &args) != NULL) return (-1); args.flags = LA_SER_LIBPATH; - if (path_enumerate(ld_library_path, fill_search_info, &args) != NULL) + if (path_enumerate(ld_library_path, fill_search_info, NULL, &args) != NULL) return (-1); args.flags = LA_SER_RUNPATH; - if (path_enumerate(obj->runpath, fill_search_info, &args) != NULL) + if (path_enumerate(obj->runpath, fill_search_info, NULL, &args) != NULL) return (-1); args.flags = LA_SER_CONFIG; - if (path_enumerate(gethints(obj->z_nodeflib), fill_search_info, &args) + if (path_enumerate(gethints(obj->z_nodeflib), fill_search_info, NULL, &args) != NULL) return (-1); args.flags = LA_SER_DEFAULT; - if (!obj->z_nodeflib && - path_enumerate(ld_standard_library_path, fill_search_info, &args) != NULL) + if (!obj->z_nodeflib && path_enumerate(ld_standard_library_path, + fill_search_info, NULL, &args) != NULL) return (-1); return (0); }
Andreas Longwitz
2018-Sep-24 22:03 UTC
Constraints in libmap(32).conf do not work as expected, possible bug in rtld-elf
> > Can you try this instead ? >Yes I did on a server running FreeBSD 12.0-CURRENT (GENERIC) #0 r337452 and - after a trivial adaptation of your patch - on FreeBSD 10.4-STABLE #0 r337823 and everything works correct. My simple libmap32.conf now is: ## php52 [/usr/local/php52/] /usr/local/lib /usr/local/lib32 /usr/local/lib/mysql /usr/local/lib32/mysql [libc-client4.so.9] libssl.so.8 libssl.so.6 libcrypto.so.8 libcrypto.so.6 My test command "/usr/local/php52/bin/php -i" loads also all the shared objects in /usr/local/php52/lib/php/20060613: gettext.so iconv.so imap.so mbstring.so mcrypt.so mysql.so pcre.so session.so xml.so. Further ldd gives correct output for every mentioned file. I like to mention one thing concerning the source libmap.c. With the patch (yours or mine) and the libmap32.conf given above I see the following lmp_list when lm_fini() is called: lm_fini("1, $DEFAULT$" lml-Adresse 0x2826c208) lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib/mysql, t=/usr/local/lib32/mysql") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=libcrypto.so.8, t=libcrypto.so.6") lm_fini("f=libssl.so.8, t=libssl.so.6") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") lm_fini("1, libc-client4.so.9" lml-Adresse 0x2826c168) lm_fini("f=libcrypto.so.8, t=libcrypto.so.6") lm_fini("f=libssl.so.8, t=libssl.so.6") lm_fini("2, /usr/local/php52/" lml-Adresse 0x2826c068) lm_fini("f=/usr/local/lib/mysql, t=/usr/local/lib32/mysql") lm_fini("f=/usr/local/lib, t=/usr/local/lib32") So for $DEFAULTS we have a lot of identical entries. This comes from the TAILQ_INSERT_HEAD statement in lm_add(). I am not sure if this can be accepted or a check to avoid double entries in the list is better. One annotation to the script /etc/rc.d/ldconfig: I had expected that this script during boot creates clean files ld-elf(32).so.hints in /var/run. For 64 bit this is true, but for 32 bit not because ldconfig with flag -32 also has flag -m. Is this intended behaviour ? Andreas Longwitz