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authorRich Felker <dalias@aerifal.cx>2013-08-23 11:15:40 -0400
committerRich Felker <dalias@aerifal.cx>2013-08-23 11:15:40 -0400
commit709355e1f6dad17234606486400568bc87a37d79 (patch)
treec00d7fb1f70241128ac22182062314217b1a9775 /src/ldso/dynlink.c
parent8b491f1499b8636efe8a99d940f0c87b9a3ba9ae (diff)
downloadmusl-709355e1f6dad17234606486400568bc87a37d79.tar.gz
add recursive rpath support to dynamic linker
previously, rpath was only honored for direct dependencies. in other words, if A depends on B and B depends on C, only B's rpath (if any), not A's rpath, was being searched for C. this limitation made rpath-based deployment difficult in the presence of multiple levels of library dependency. at present, $ORIGIN processing in rpath is still unsupported.
Diffstat (limited to 'src/ldso/dynlink.c')
-rw-r--r--src/ldso/dynlink.c25
1 files changed, 13 insertions, 12 deletions
diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index ad987b8f..8c5b9625 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -72,7 +72,8 @@ struct dso {
signed char global;
char relocated;
char constructed;
- struct dso **deps;
+ struct dso **deps, *needed_by;
+ char *rpath;
void *tls_image;
size_t tls_len, tls_size, tls_align, tls_id, tls_offset;
void **new_dtv;
@@ -95,7 +96,7 @@ void *__install_initial_tls(void *);
void __init_libc(char **, char *);
static struct dso *head, *tail, *ldso, *fini_head;
-static char *env_path, *sys_path, *r_path;
+static char *env_path, *sys_path;
static unsigned long long gencnt;
static int ssp_used;
static int runtime;
@@ -455,13 +456,15 @@ static void decode_dyn(struct dso *p)
p->strings = (void *)(p->base + dyn[DT_STRTAB]);
if (dyn[0]&(1<<DT_HASH))
p->hashtab = (void *)(p->base + dyn[DT_HASH]);
+ if (dyn[0]&(1<<DT_RPATH))
+ p->rpath = (void *)(p->strings + dyn[DT_RPATH]);
if (search_vec(p->dynv, dyn, DT_GNU_HASH))
p->ghashtab = (void *)(p->base + *dyn);
if (search_vec(p->dynv, dyn, DT_VERSYM))
p->versym = (void *)(p->base + *dyn);
}
-static struct dso *load_library(const char *name)
+static struct dso *load_library(const char *name, struct dso *needed_by)
{
char buf[2*NAME_MAX+2];
const char *pathname;
@@ -521,7 +524,9 @@ static struct dso *load_library(const char *name)
if (strlen(name) > NAME_MAX) return 0;
fd = -1;
if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
- if (fd < 0 && r_path) fd = path_open(name, r_path, buf, sizeof buf);
+ for (p=needed_by; fd < 0 && p; p=p->needed_by)
+ if (p->rpath)
+ fd = path_open(name, p->rpath, buf, sizeof buf);
if (fd < 0) {
if (!sys_path) {
char *prefix = 0;
@@ -601,6 +606,7 @@ static struct dso *load_library(const char *name)
p->dev = st.st_dev;
p->ino = st.st_ino;
p->refcnt = 1;
+ p->needed_by = needed_by;
p->name = p->buf;
strcpy(p->name, pathname);
/* Add a shortname only if name arg was not an explicit pathname. */
@@ -643,12 +649,8 @@ static void load_deps(struct dso *p)
struct dso ***deps = &p->deps, **tmp, *dep;
for (; p; p=p->next) {
for (i=0; p->dynv[i]; i+=2) {
- if (p->dynv[i] != DT_RPATH) continue;
- r_path = (void *)(p->strings + p->dynv[i+1]);
- }
- for (i=0; p->dynv[i]; i+=2) {
if (p->dynv[i] != DT_NEEDED) continue;
- dep = load_library(p->strings + p->dynv[i+1]);
+ dep = load_library(p->strings + p->dynv[i+1], p);
if (!dep) {
snprintf(errbuf, sizeof errbuf,
"Error loading shared library %s: %m (needed by %s)",
@@ -666,7 +668,6 @@ static void load_deps(struct dso *p)
*deps = tmp;
}
}
- r_path = 0;
}
}
@@ -679,7 +680,7 @@ static void load_preload(char *s)
for (z=s; *z && !isspace(*z); z++);
tmp = *z;
*z = 0;
- load_library(s);
+ load_library(s, 0);
*z = tmp;
}
}
@@ -1153,7 +1154,7 @@ void *dlopen(const char *file, int mode)
p = 0;
errflag = 1;
goto end;
- } else p = load_library(file);
+ } else p = load_library(file, 0);
if (!p) {
snprintf(errbuf, sizeof errbuf, noload ?