diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Versions | 2 | ||||
| -rw-r--r-- | elf/dl-tunables.c | 58 | ||||
| -rw-r--r-- | elf/dl-tunables.h | 53 |
3 files changed, 72 insertions, 41 deletions
diff --git a/elf/Versions b/elf/Versions index 6abe9db8bd..c59facdbd7 100644 --- a/elf/Versions +++ b/elf/Versions @@ -72,6 +72,6 @@ ld { _dl_signal_error; _dl_catch_error; # Set value of a tunable. - __tunable_set_val; + __tunable_get_val; } } diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c index b6e6b3da52..76e8c5cae1 100644 --- a/elf/dl-tunables.c +++ b/elf/dl-tunables.c @@ -184,19 +184,17 @@ tunables_strtoul (const char *nptr) if ((__type) (__val) >= min && (__type) (val) <= max) \ { \ (__cur)->val.numval = val; \ - (__cur)->strval = strval; \ + (__cur)->initialized = true; \ } \ }) -/* Validate range of the input value and initialize the tunable CUR if it looks - good. */ static void -tunable_initialize (tunable_t *cur, const char *strval) +do_tunable_update_val (tunable_t *cur, const void *valp) { uint64_t val; if (cur->type.type_code != TUNABLE_TYPE_STRING) - val = tunables_strtoul (strval); + val = *((int64_t *) valp); switch (cur->type.type_code) { @@ -217,7 +215,7 @@ tunable_initialize (tunable_t *cur, const char *strval) } case TUNABLE_TYPE_STRING: { - cur->val.strval = cur->strval = strval; + cur->val.strval = valp; break; } default: @@ -225,6 +223,35 @@ tunable_initialize (tunable_t *cur, const char *strval) } } +/* Validate range of the input value and initialize the tunable CUR if it looks + good. */ +static void +tunable_initialize (tunable_t *cur, const char *strval) +{ + uint64_t val; + const void *valp; + + if (cur->type.type_code != TUNABLE_TYPE_STRING) + { + val = tunables_strtoul (strval); + valp = &val; + } + else + { + cur->initialized = true; + valp = strval; + } + do_tunable_update_val (cur, valp); +} + +void +__tunable_set_val (tunable_id_t id, void *valp) +{ + tunable_t *cur = &tunable_list[id]; + + do_tunable_update_val (cur, valp); +} + #if TUNABLES_FRONTEND == TUNABLES_FRONTEND_valstring /* Parse the tunable string TUNESTR and adjust it to drop any tunables that may be unsafe for AT_SECURE processes so that it can be used as the new @@ -375,7 +402,7 @@ __tunables_init (char **envp) /* Skip over tunables that have either been set already or should be skipped. */ - if (cur->strval != NULL || cur->env_alias == NULL) + if (cur->initialized || cur->env_alias == NULL) continue; const char *name = cur->env_alias; @@ -426,20 +453,10 @@ __tunables_init (char **envp) /* Set the tunable value. This is called by the module that the tunable exists in. */ void -__tunable_set_val (tunable_id_t id, void *valp, tunable_callback_t callback) +__tunable_get_val (tunable_id_t id, void *valp, tunable_callback_t callback) { tunable_t *cur = &tunable_list[id]; - /* Don't do anything if our tunable was not set during initialization or if - it failed validation. */ - if (cur->strval == NULL) - return; - - /* Caller does not need the value, just call the callback with our tunable - value. */ - if (valp == NULL) - goto cb; - switch (cur->type.type_code) { case TUNABLE_TYPE_UINT_64: @@ -466,9 +483,8 @@ __tunable_set_val (tunable_id_t id, void *valp, tunable_callback_t callback) __builtin_unreachable (); } -cb: - if (callback) + if (cur->initialized && callback != NULL) callback (&cur->val); } -rtld_hidden_def (__tunable_set_val) +rtld_hidden_def (__tunable_get_val) diff --git a/elf/dl-tunables.h b/elf/dl-tunables.h index 20ee51254e..6c49dcbf47 100644 --- a/elf/dl-tunables.h +++ b/elf/dl-tunables.h @@ -39,8 +39,8 @@ struct _tunable const char *name; /* Internal name of the tunable. */ tunable_type_t type; /* Data type of the tunable. */ tunable_val_t val; /* The value. */ - const char *strval; /* The string containing the value, - points into envp. */ + bool initialized; /* Flag to indicate that the tunable is + initialized. */ tunable_seclevel_t security_level; /* Specify the security level for the tunable with respect to AT_SECURE programs. See description of @@ -61,37 +61,52 @@ typedef struct _tunable tunable_t; /* Full name for a tunable is top_ns.tunable_ns.id. */ # define TUNABLE_NAME_S(top,ns,id) #top "." #ns "." #id -# define TUNABLE_ENUM_NAME(top,ns,id) TUNABLE_ENUM_NAME1 (top,ns,id) -# define TUNABLE_ENUM_NAME1(top,ns,id) top ## _ ## ns ## _ ## id +# define TUNABLE_ENUM_NAME(__top,__ns,__id) TUNABLE_ENUM_NAME1 (__top,__ns,__id) +# define TUNABLE_ENUM_NAME1(__top,__ns,__id) __top ## _ ## __ns ## _ ## __id # include "dl-tunable-list.h" extern void __tunables_init (char **); -extern void __tunable_set_val (tunable_id_t, void *, tunable_callback_t); - +extern void __tunable_get_val (tunable_id_t, void *, tunable_callback_t); +extern void __tunable_set_val (tunable_id_t, void *); rtld_hidden_proto (__tunables_init) -rtld_hidden_proto (__tunable_set_val) +rtld_hidden_proto (__tunable_get_val) + +/* Define TUNABLE_GET and TUNABLE_SET in short form if TOP_NAMESPACE and + TUNABLE_NAMESPACE are defined. This is useful shorthand to get and set + tunables within a module. */ +#if defined TOP_NAMESPACE && defined TUNABLE_NAMESPACE +# define TUNABLE_GET(__id, __type, __cb) \ + TUNABLE_GET_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, __type, __cb) +# define TUNABLE_SET(__id, __type, __val) \ + TUNABLE_SET_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, __type, __val) +#else +# define TUNABLE_GET(__top, __ns, __id, __type, __cb) \ + TUNABLE_GET_FULL (__top, __ns, __id, __type, __cb) +# define TUNABLE_SET(__top, __ns, __id, __type, __val) \ + TUNABLE_SET_FULL (__top, __ns, __id, __type, __val) +#endif -/* Check if the tunable has been set to a non-default value and if it is, copy - it over into __VAL. */ -# define TUNABLE_SET_VAL(__id,__val) \ +/* Get and return a tunable value. If the tunable was set externally and __CB + is defined then call __CB before returning the value. */ +# define TUNABLE_GET_FULL(__top, __ns, __id, __type, __cb) \ ({ \ - __tunable_set_val \ - (TUNABLE_ENUM_NAME (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id), (__val), \ - NULL); \ + tunable_id_t id = TUNABLE_ENUM_NAME (__top, __ns, __id); \ + __type ret; \ + __tunable_get_val (id, &ret, __cb); \ + ret; \ }) -/* Same as TUNABLE_SET_VAL, but also call the callback function __CB. */ -# define TUNABLE_SET_VAL_WITH_CALLBACK(__id,__val,__cb) \ +/* Set a tunable value. */ +# define TUNABLE_SET_FULL(__top, __ns, __id, __type, __val) \ ({ \ - __tunable_set_val \ - (TUNABLE_ENUM_NAME (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id), (__val), \ - DL_TUNABLE_CALLBACK (__cb)); \ + __tunable_set_val (TUNABLE_ENUM_NAME (__top, __ns, __id), \ + & (__type) {__val}); \ }) /* Namespace sanity for callback functions. Use this macro to keep the namespace of the modules clean. */ -# define DL_TUNABLE_CALLBACK(__name) _dl_tunable_ ## __name +# define TUNABLE_CALLBACK(__name) _dl_tunable_ ## __name # define TUNABLES_FRONTEND_valstring 1 /* The default value for TUNABLES_FRONTEND. */ |