smbd: Simplify smb_q_posix_symlink()

Use the dirfsp from call_trans2qpathinfo(), avoid a call to parent_pathref()

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

diff --git a/source3/smbd/smb1_trans2.c b/source3/smbd/smb1_trans2.c
index 1014cdcfb225e6743fa2e456a0d3cbc01170db18..4da75f760d78ca5445cc79be2aa3a421e5858299 100644 (file)
--- a/source3/smbd/smb1_trans2.c
+++ b/source3/smbd/smb1_trans2.c
@@ -2529,16 +2529,14 @@ static NTSTATUS smb_q_posix_acl(
 static NTSTATUS smb_q_posix_symlink(
        struct connection_struct *conn,
        struct smb_request *req,
+       struct files_struct *dirfsp,
        struct smb_filename *smb_fname,
        char **ppdata,
        int *ptotal_data)
 {
-       char buffer[PATH_MAX+1];
+       char *target = NULL;
        size_t needed, len;
-       int link_len;
        char *pdata = NULL;
-       struct smb_filename *parent_fname = NULL;
-       struct smb_filename *base_name = NULL;
        NTSTATUS status;
 
        DBG_DEBUG("SMB_QUERY_FILE_UNIX_LINK for file %s\n",
@@ -2548,40 +2546,39 @@ static NTSTATUS smb_q_posix_symlink(
                return NT_STATUS_DOS(ERRSRV, ERRbadlink);
        }
 
-       status = parent_pathref(
-               talloc_tos(),
-               conn->cwd_fsp,
-               smb_fname,
-               &parent_fname,
-               &base_name);
+       if (fsp_get_pathref_fd(smb_fname->fsp) != -1) {
+               /*
+                * fsp is an O_PATH open, Linux does a "freadlink"
+                * with an empty name argument to readlinkat
+                */
+               status = readlink_talloc(talloc_tos(),
+                                        smb_fname->fsp,
+                                        NULL,
+                                        &target);
+       } else {
+               struct smb_filename smb_fname_rel = *smb_fname;
+               char *slash = NULL;
 
-       if (!NT_STATUS_IS_OK(status)) {
-               DBG_DEBUG("parent_pathref failed: %s\n", nt_errstr(status));
-               return status;
+               slash = strrchr_m(smb_fname->base_name, '/');
+               if (slash != NULL) {
+                       smb_fname_rel.base_name = slash + 1;
+               }
+               status = readlink_talloc(talloc_tos(),
+                                        dirfsp,
+                                        &smb_fname_rel,
+                                        &target);
        }
 
-       link_len = SMB_VFS_READLINKAT(
-               conn,
-               parent_fname->fsp,
-               base_name,
-               buffer,
-               sizeof(buffer)-1);
-       TALLOC_FREE(parent_fname);
-
-       if (link_len == -1) {
-               status = map_nt_error_from_unix(errno);
-               DBG_DEBUG("READLINKAT failed: %s\n", nt_errstr(status));
+       if (!NT_STATUS_IS_OK(status)) {
+               DBG_DEBUG("readlink_talloc() failed: %s\n", nt_errstr(status));
                return status;
        }
-       if (link_len >= sizeof(buffer)) {
-               return NT_STATUS_INTERNAL_ERROR;
-       }
-       buffer[link_len] = 0;
 
-       needed = (link_len+1)*2;
+       needed = talloc_get_size(target) * 2;
 
        *ppdata = SMB_REALLOC(*ppdata, needed);
        if (*ppdata == NULL) {
+               TALLOC_FREE(target);
                return NT_STATUS_NO_MEMORY;
        }
        pdata = *ppdata;
@@ -2590,10 +2587,11 @@ static NTSTATUS smb_q_posix_symlink(
                pdata,
                req->flags2,
                pdata,
-               buffer,
+               target,
                needed,
                STR_TERMINATE,
                &len);
+       TALLOC_FREE(target);
        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }
@@ -2783,6 +2781,7 @@ static void call_trans2qpathinfo(
                status = smb_q_posix_symlink(
                        conn,
                        req,
+                       dirfsp,
                        smb_fname,
                        ppdata,
                        &total_data);