diff --git a/LibOS/shim/src/sys/shim_access.c b/LibOS/shim/src/sys/shim_access.c
index a3fb6251..8df9c06e 100644
--- a/LibOS/shim/src/sys/shim_access.c
+++ b/LibOS/shim/src/sys/shim_access.c
@@ -18,24 +18,7 @@
 #include "shim_thread.h"
 
 int shim_do_access(const char* file, mode_t mode) {
-    if (!file)
-        return -EINVAL;
-
-    if (test_user_string(file))
-        return -EFAULT;
-
-    struct shim_dentry* dent = NULL;
-    int ret = 0;
-
-    lock(&dcache_lock);
-
-    ret = __path_lookupat(NULL, file, LOOKUP_ACCESS | LOOKUP_FOLLOW, &dent, 0, NULL, false);
-    if (!ret)
-        ret = __permission(dent, mode);
-
-    unlock(&dcache_lock);
-
-    return ret;
+    return shim_do_faccessat(AT_FDCWD, file, mode);
 }
 
 int shim_do_faccessat(int dfd, const char* filename, mode_t mode) {
@@ -49,7 +32,7 @@ int shim_do_faccessat(int dfd, const char* filename, mode_t mode) {
     struct shim_dentry* dent = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*filename != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     lock(&dcache_lock);
@@ -63,6 +46,7 @@ int shim_do_faccessat(int dfd, const char* filename, mode_t mode) {
 out:
     unlock(&dcache_lock);
 
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
diff --git a/LibOS/shim/src/sys/shim_fs.c b/LibOS/shim/src/sys/shim_fs.c
index 32e8cf5b..91d78b76 100644
--- a/LibOS/shim/src/sys/shim_fs.c
+++ b/LibOS/shim/src/sys/shim_fs.c
@@ -26,34 +26,7 @@
 /* The kernel would look up the parent directory, and remove the child from the inode. But we are
  * working with the PAL, so we open the file, truncate and close it. */
 int shim_do_unlink(const char* file) {
-    if (!file)
-        return -EINVAL;
-
-    if (test_user_string(file))
-        return -EFAULT;
-
-    struct shim_dentry* dent = NULL;
-    int ret = 0;
-
-    if ((ret = path_lookupat(NULL, file, LOOKUP_OPEN, &dent, NULL)) < 0)
-        return ret;
-
-    if (!dent->parent)
-        return -EACCES;
-
-    if (dent->state & DENTRY_ISDIRECTORY)
-        return -EISDIR;
-
-    if (dent->fs && dent->fs->d_ops && dent->fs->d_ops->unlink) {
-        if ((ret = dent->fs->d_ops->unlink(dent->parent, dent)) < 0)
-            return ret;
-    } else {
-        dent->state |= DENTRY_PERSIST;
-    }
-
-    dent->state |= DENTRY_NEGATIVE;
-    put_dentry(dent);
-    return 0;
+    return shim_do_unlinkat(AT_FDCWD, file, 0);
 }
 
 int shim_do_unlinkat(int dfd, const char* pathname, int flag) {
@@ -70,7 +43,7 @@ int shim_do_unlinkat(int dfd, const char* pathname, int flag) {
     struct shim_dentry* dent = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*pathname != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     if ((ret = path_lookupat(dir, pathname, LOOKUP_OPEN, &dent, NULL)) < 0)
@@ -103,12 +76,13 @@ int shim_do_unlinkat(int dfd, const char* pathname, int flag) {
 out_dent:
     put_dentry(dent);
 out:
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
 
 int shim_do_mkdir(const char* pathname, int mode) {
-    return open_namei(NULL, NULL, pathname, O_CREAT | O_EXCL | O_DIRECTORY, mode, NULL);
+    return shim_do_mkdirat(AT_FDCWD, pathname, mode);
 }
 
 int shim_do_mkdirat(int dfd, const char* pathname, int mode) {
@@ -121,12 +95,13 @@ int shim_do_mkdirat(int dfd, const char* pathname, int mode) {
     struct shim_dentry* dir = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*pathname != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     ret = open_namei(NULL, dir, pathname, O_CREAT | O_EXCL | O_DIRECTORY, mode, NULL);
 
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
 
@@ -177,29 +152,7 @@ mode_t shim_do_umask(mode_t mask) {
 }
 
 int shim_do_chmod(const char* path, mode_t mode) {
-    struct shim_dentry* dent = NULL;
-    int ret = 0;
-
-    /* This isn't documented, but that's what Linux does. */
-    mode &= 07777;
-
-    if (test_user_string(path))
-        return -EFAULT;
-
-    if ((ret = path_lookupat(NULL, path, LOOKUP_OPEN, &dent, NULL)) < 0)
-        return ret;
-
-    if (dent->fs && dent->fs->d_ops && dent->fs->d_ops->chmod) {
-        if ((ret = dent->fs->d_ops->chmod(dent, mode)) < 0)
-            goto out;
-    } else {
-        dent->state |= DENTRY_PERSIST;
-    }
-
-    dent->mode = mode;
-out:
-    put_dentry(dent);
-    return ret;
+    return shim_do_fchmodat(AT_FDCWD, path, mode);
 }
 
 int shim_do_fchmodat(int dfd, const char* filename, mode_t mode) {
@@ -216,7 +169,7 @@ int shim_do_fchmodat(int dfd, const char* filename, mode_t mode) {
     struct shim_dentry* dent = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*filename != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     if ((ret = path_lookupat(dir, filename, LOOKUP_OPEN, &dent, NULL)) < 0)
@@ -233,7 +186,8 @@ int shim_do_fchmodat(int dfd, const char* filename, mode_t mode) {
 out_dent:
     put_dentry(dent);
 out:
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
 
@@ -262,23 +216,7 @@ out:
 }
 
 int shim_do_chown(const char* path, uid_t uid, gid_t gid) {
-    struct shim_dentry* dent = NULL;
-    int ret = 0;
-    __UNUSED(uid);
-    __UNUSED(gid);
-
-    if (!path)
-        return -EINVAL;
-
-    if (test_user_string(path))
-        return -EFAULT;
-
-    if ((ret = path_lookupat(NULL, path, LOOKUP_OPEN, &dent, NULL)) < 0)
-        return ret;
-
-    /* XXX: do nothing now */
-    put_dentry(dent);
-    return ret;
+    return shim_do_fchownat(AT_FDCWD, path, uid, gid, 0);
 }
 
 int shim_do_fchownat(int dfd, const char* filename, uid_t uid, gid_t gid, int flags) {
@@ -296,7 +234,7 @@ int shim_do_fchownat(int dfd, const char* filename, uid_t uid, gid_t gid, int fl
     struct shim_dentry* dent = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*filename != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     if ((ret = path_lookupat(dir, filename, LOOKUP_OPEN, &dent, NULL)) < 0)
@@ -305,7 +243,8 @@ int shim_do_fchownat(int dfd, const char* filename, uid_t uid, gid_t gid, int fl
     /* XXX: do nothing now */
     put_dentry(dent);
 out:
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
 
@@ -621,7 +560,7 @@ int shim_do_renameat(int olddirfd, const char* oldpath, int newdirfd, const char
         return -EFAULT;
     }
 
-    if ((ret = get_dirfd_dentry(olddirfd, &old_dir_dent)) < 0) {
+    if (*oldpath != '/' && (ret = get_dirfd_dentry(olddirfd, &old_dir_dent)) < 0) {
         goto out;
     }
 
@@ -634,7 +573,7 @@ int shim_do_renameat(int olddirfd, const char* oldpath, int newdirfd, const char
         goto out;
     }
 
-    if ((ret = get_dirfd_dentry(newdirfd, &new_dir_dent)) < 0) {
+    if (*newpath != '/' && (ret = get_dirfd_dentry(newdirfd, &new_dir_dent)) < 0) {
         goto out;
     }
 
diff --git a/LibOS/shim/src/sys/shim_open.c b/LibOS/shim/src/sys/shim_open.c
index 770d8874..f018f357 100644
--- a/LibOS/shim/src/sys/shim_open.c
+++ b/LibOS/shim/src/sys/shim_open.c
@@ -88,30 +88,7 @@ size_t shim_do_write(int fd, const void* buf, size_t count) {
 }
 
 int shim_do_open(const char* file, int flags, mode_t mode) {
-    if (!file || test_user_string(file))
-        return -EFAULT;
-
-    if (!(flags & O_CREAT)) {
-        /* `mode` should be ignored if O_CREAT is not specified, according to man */
-        mode = 0;
-    } else {
-        /* This isn't documented, but that's what Linux does. */
-        mode &= 07777;
-    }
-
-    struct shim_handle* hdl = get_new_handle();
-    if (!hdl)
-        return -ENOMEM;
-
-    int ret = 0;
-    ret = open_namei(hdl, NULL, file, flags, mode, NULL);
-    if (ret < 0)
-        goto out;
-
-    ret = set_new_fd_handle(hdl, flags & O_CLOEXEC ? FD_CLOEXEC : 0, NULL);
-out:
-    put_handle(hdl);
-    return ret;
+    return shim_do_openat(AT_FDCWD, file, flags, mode);
 }
 
 int shim_do_creat(const char* path, mode_t mode) {
@@ -133,7 +110,7 @@ int shim_do_openat(int dfd, const char* filename, int flags, int mode) {
     struct shim_dentry* dir = NULL;
     int ret = 0;
 
-    if ((ret = get_dirfd_dentry(dfd, &dir)) < 0)
+    if (*filename != '/' && (ret = get_dirfd_dentry(dfd, &dir)) < 0)
         return ret;
 
     struct shim_handle* hdl = get_new_handle();
@@ -151,7 +128,8 @@ int shim_do_openat(int dfd, const char* filename, int flags, int mode) {
 out_hdl:
     put_handle(hdl);
 out:
-    put_dentry(dir);
+    if (dir)
+        put_dentry(dir);
     return ret;
 }
 
diff --git a/LibOS/shim/src/sys/shim_pipe.c b/LibOS/shim/src/sys/shim_pipe.c
index 4b081caa..59157540 100644
--- a/LibOS/shim/src/sys/shim_pipe.c
+++ b/LibOS/shim/src/sys/shim_pipe.c
@@ -274,10 +274,8 @@ int shim_do_mknodat(int dirfd, const char* pathname, mode_t mode, dev_t dev) {
     struct shim_dentry* dir  = NULL;
     struct shim_dentry* dent = NULL;
 
-    ret = get_dirfd_dentry(dirfd, &dir);
-    if (ret < 0) {
+    if (*pathname != '/' && (ret = get_dirfd_dentry(dirfd, &dir)) < 0)
         goto out;
-    }
 
     ret = path_lookupat(dir, pathname, LOOKUP_CREATE, &dent, NULL);
     if (ret < 0 && ret != -ENOENT) {
diff --git a/LibOS/shim/src/sys/shim_stat.c b/LibOS/shim/src/sys/shim_stat.c
index 2cb0527e..59e8172a 100644
--- a/LibOS/shim/src/sys/shim_stat.c
+++ b/LibOS/shim/src/sys/shim_stat.c
@@ -91,6 +91,7 @@ out:
 }
 
 int shim_do_readlinkat(int dirfd, const char* file, char* buf, int bufsize) {
+    int ret;
     if (!file || test_user_string(file))
         return -EFAULT;
 
@@ -102,10 +103,9 @@ int shim_do_readlinkat(int dirfd, const char* file, char* buf, int bufsize) {
 
     struct shim_dentry* dent = NULL;
     struct shim_dentry* dir = NULL;
-    int ret = get_dirfd_dentry(dirfd, &dir);
-    if (ret < 0) {
+
+    if (*file != '/' && (ret = get_dirfd_dentry(dirfd, &dir)) < 0)
         goto out;
-    }
 
     struct shim_qstr qstr = QSTR_INIT;
 
diff --git a/LibOS/shim/test/ltp/ltp.cfg b/LibOS/shim/test/ltp/ltp.cfg
index 4adb860e..d2d962fb 100644
--- a/LibOS/shim/test/ltp/ltp.cfg
+++ b/LibOS/shim/test/ltp/ltp.cfg
@@ -1942,9 +1942,6 @@ skip = yes
 [rename13]
 skip = yes
 
-[rename14]
-skip = yes
-
 [renameat01]
 skip = yes