X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=blobdiff_plain;f=src%2Fldso%2Fdynlink.c;h=56ba89eb57b4f20f90ed2753de1d2df84b2ea80f;hp=b44442526034ac0a15a634cb137734ffaef9598e;hb=59633c736dcf6dcd11c24edab4803c85b8462bf6;hpb=51e2d8310222ddd4d4e895f55c627100d863aa95

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index b4444252..56ba89eb 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -35,7 +35,7 @@ struct dso
 	int refcnt;
 	size_t *dynv;
 	Sym *syms;
-	size_t *hashtab;
+	uint32_t *hashtab;
 	char *strings;
 	unsigned char *base;
 	unsigned char *map;
@@ -48,6 +48,7 @@ struct dso
 };
 
 static struct dso *head, *tail, *libc;
+static char *env_path, *sys_path;
 
 #define AUX_CNT 15
 #define DYN_CNT 34
@@ -71,7 +72,7 @@ static uint32_t hash(const char *s)
 	return h & 0xfffffff;
 }
 
-static Sym *lookup(const char *s, uint32_t h, Sym *syms, size_t *hashtab, char *strings)
+static Sym *lookup(const char *s, uint32_t h, Sym *syms, uint32_t *hashtab, char *strings)
 {
 	size_t i;
 	for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
@@ -122,7 +123,7 @@ static void do_relocs(unsigned char *base, size_t *rel, size_t rel_size, size_t
 
 static void *map_library(int fd, size_t *lenp, unsigned char **basep, size_t *dynp)
 {
-	size_t buf[896/sizeof(size_t)];
+	Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
 	size_t phsize;
 	size_t addr_min=SIZE_MAX, addr_max=0, map_len;
 	size_t this_min, this_max;
@@ -136,11 +137,11 @@ static void *map_library(int fd, size_t *lenp, unsigned char **basep, size_t *dy
 
 	ssize_t l = read(fd, buf, sizeof buf);
 	if (l<sizeof *eh) return 0;
-	eh = (void *)buf;
+	eh = buf;
 	phsize = eh->e_phentsize * eh->e_phnum;
 	if (phsize + sizeof *eh > l) return 0;
 	if (eh->e_phoff + phsize > l) {
-		l = pread(fd, buf+sizeof *eh, phsize, eh->e_phoff);
+		l = pread(fd, buf+1, phsize, eh->e_phoff);
 		if (l != phsize) return 0;
 		eh->e_phoff = sizeof *eh;
 	}
@@ -204,6 +205,20 @@ static void *map_library(int fd, size_t *lenp, unsigned char **basep, size_t *dy
 	return map;
 }
 
+static int path_open(const char *name, const char *search)
+{
+	char buf[2*NAME_MAX+2];
+	const char *s, *z;
+	int l, fd;
+	for (s=search; *s; s+=l+!!z) {
+		z = strchr(s, ':');
+		l = z ? z-s : strlen(s);
+		snprintf(buf, sizeof buf, "%.*s/%s", l, s, name);
+		if ((fd = open(buf, O_RDONLY))>=0) return fd;
+	}
+	return -1;
+}
+
 static struct dso *load_library(const char *name)
 {
 	unsigned char *base, *map;
@@ -241,14 +256,20 @@ static struct dso *load_library(const char *name)
 	if (name[0] == '/') {
 		fd = open(name, O_RDONLY);
 	} else {
-		static const char path[] = "/lib/\0/usr/local/lib/\0/usr/lib/\0";
-		const char *s;
-		char buf[NAME_MAX+32];
 		if (strlen(name) > NAME_MAX || strchr(name, '/')) return 0;
-		for (s=path; *s; s+=strlen(s)+1) {
-			strcpy(buf, s);
-			strcat(buf, name);
-			if ((fd = open(buf, O_RDONLY))>=0) break;
+		fd = -1;
+		if (env_path) fd = path_open(name, env_path);
+		if (fd < 0) {
+			if (!sys_path) {
+				FILE *f = fopen(ETC_LDSO_PATH, "r");
+				if (f) {
+					if (getline(&sys_path, (size_t[1]){0}, f) > 0)
+						sys_path[strlen(sys_path)-1]=0;
+					fclose(f);
+				}
+			}
+			if (sys_path) fd = path_open(name, sys_path);
+			else fd = path_open(name, "/lib:/usr/local/lib:/usr/lib");
 		}
 	}
 	if (fd < 0) return 0;
@@ -317,6 +338,17 @@ static void reloc_all(struct dso *p)
 			2, p->syms, p->strings, p);
 		do_relocs(p->base, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ],
 			3, p->syms, p->strings, p);
+		p->relocated = 1;
+	}
+}
+
+static void free_all(struct dso *p)
+{
+	struct dso *n;
+	while (p) {
+		n = p->next;
+		if (p->map) free(p);
+		p = n;
 	}
 }
 
@@ -330,11 +362,19 @@ void *__dynlink(int argc, char **argv, size_t *got)
 	struct dso lib, app;
 
 	/* Find aux vector just past environ[] */
-	for (i=argc+1; argv[i]; i++);
+	for (i=argc+1; argv[i]; i++)
+		if (!memcmp(argv[i], "LD_LIBRARY_PATH=", 16))
+			env_path = argv[i]+16;
 	auxv = (void *)(argv+i+1);
 
 	decode_vec(auxv, aux, AUX_CNT);
 
+	/* Only trust user/env if kernel says we're not suid/sgid */
+	if ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
+	  || aux[AT_GID]!=aux[AT_EGID]) {
+		env_path = 0;
+	}
+
 	/* Relocate ldso's DYNAMIC pointer and load vector */
 	decode_vec((void *)(got[0] += aux[AT_BASE]), lib_dyn, DYN_CNT);
 
@@ -380,6 +420,9 @@ void *__dynlink(int argc, char **argv, size_t *got)
 
 	reloc_all(head);
 
+	free_all(head);
+	free(sys_path);
+
 	errno = 0;
 	return (void *)aux[AT_ENTRY];
 }