[CRIU] [PATCH v2 08/11] dump: hide regular file open

[Kinsbursky Stanislav]

Signed-off-by: Stanislav Kinsbursky <skinsbursky at openvz.org>

---
 cr-dump.c |   44 ++++++++++++++++++++++++++------------------
 1 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/cr-dump.c b/cr-dump.c
index 8494820..03062e5 100644
--- a/cr-dump.c
+++ b/cr-dump.c
@@ -99,20 +99,19 @@ struct fd_parms {
 	pid_t		pid;
 };
 
-static int dump_one_reg_file(struct fd_parms *p, int lfd,
-			     struct cr_fdset *cr_fdset,
-			     bool do_close_lfd)
+static int dump_one_reg_file_fd(struct fd_parms *p, int lfd,
+				struct cr_fdset *cr_fdset,
+				bool do_close_lfd)
 {
 	struct fdinfo_entry e;
 	char fd_str[128];
 	int len;
-	int ret = -1;
 
 	snprintf(fd_str, sizeof(fd_str), "/proc/self/fd/%d", lfd);
 	len = readlink(fd_str, big_buffer, sizeof(big_buffer) - 1);
 	if (len < 0) {
 		pr_perror("Can't readlink %s", fd_str);
-		goto err;
+		return -1;
 	}
 
 	big_buffer[len] = '\0';
@@ -140,7 +139,7 @@ static int dump_one_reg_file(struct fd_parms *p, int lfd,
 
 		entry = fd_id_entry_collect((u32)p->id, p->pid, p->fd_name);
 		if (!entry)
-			goto err;
+			return -1;
 
 		/* Now it might have completely new ID here */
 		e.id	= entry->u.id;
@@ -150,12 +149,25 @@ static int dump_one_reg_file(struct fd_parms *p, int lfd,
 		p->type, len, p->flags, p->pos, p->fd_name);
 
 	if (write_img(cr_fdset->fds[CR_FD_FDINFO], &e))
-		goto err;
+		return -1;
 	if (write_img_buf(cr_fdset->fds[CR_FD_FDINFO], big_buffer, e.len))
-		goto err;
+		return -1;
+	return 0;
+}
 
-	ret = 0;
-err:
+static int dump_one_reg_file(struct fd_parms *p, struct cr_fdset *cr_fdset)
+{
+	int ret, lfd;
+	char d_name[32];
+
+	snprintf(d_name, sizeof(d_name), "%ld", p->fd_name);
+	lfd = openat(p->pid_fd_dir, d_name, O_RDONLY);
+	if (lfd < 0) {
+		pr_perror("Failed to open regular file %d/%ld\n", p->pid_fd_dir, p->fd_name);
+		return -1;
+	}
+	ret = dump_one_reg_file_fd(p, lfd, cr_fdset, 0);
+	close_safe(&lfd);
 	return ret;
 }
 
@@ -175,7 +187,7 @@ static int dump_task_special_files(pid_t pid, struct cr_fdset *cr_fdset)
 	fd = open_proc(pid, "cwd");
 	if (fd < 0)
 		return -1;
-	ret = dump_one_reg_file(&params, fd, cr_fdset, 1);
+	ret = dump_one_reg_file_fd(&params, fd, cr_fdset, 1);
 	if (ret)
 		return ret;
 
@@ -190,7 +202,7 @@ static int dump_task_special_files(pid_t pid, struct cr_fdset *cr_fdset)
 	fd = open_proc(pid, "exe");
 	if (fd < 0)
 		return -1;
-	ret = dump_one_reg_file(&params, fd, cr_fdset, 1);
+	ret = dump_one_reg_file_fd(&params, fd, cr_fdset, 1);
 
 	return ret;
 }
@@ -338,7 +350,6 @@ static int dump_one_fd(pid_t pid, int pid_fd_dir, char *d_name, struct cr_fdset
 	struct stat fd_stat;
 	int err = -1;
 	struct fd_parms p;
-	int lfd;
 
 	err = fstatat(pid_fd_dir, d_name, &fd_stat, 0);
 	if (err < 0) {
@@ -349,8 +360,6 @@ static int dump_one_fd(pid_t pid, int pid_fd_dir, char *d_name, struct cr_fdset
 	if (read_fd_params(pid, pid_fd_dir, d_name, &fd_stat, &p))
 		return -1;
 
-	lfd = openat(p.pid_fd_dir, d_name, O_RDONLY);
-
 	switch (fd_stat.st_mode & S_IFMT) {
 	case S_IFCHR:
 		if (major(fd_stat.st_rdev) != MEM_MAJOR) {
@@ -370,7 +379,7 @@ static int dump_one_fd(pid_t pid, int pid_fd_dir, char *d_name, struct cr_fdset
 		 * Proceed to dump_one_reg_file().
 		 */
 	case S_IFREG:
-		err = dump_one_reg_file(&p, lfd, cr_fdset, 0);
+		err = dump_one_reg_file(&p, cr_fdset);
 		break;
 	case S_IFIFO:
 		err = dump_one_pipe(&p, cr_fdset);
@@ -392,7 +401,6 @@ static int dump_one_fd(pid_t pid, int pid_fd_dir, char *d_name, struct cr_fdset
 	}
 	if (err)
 		pr_err("Can't dump file %ld of that type [%x]\n", p.fd_name, fd_stat.st_mode);
-	close_safe(&lfd);
 	return err;
 }
 
@@ -483,7 +491,7 @@ static int dump_task_mappings(pid_t pid, struct list_head *vma_area_list, struct
 			else
 				p.flags = O_RDONLY;
 
-			ret = dump_one_reg_file(&p, vma_area->vm_file_fd, cr_fdset, 0);
+			ret = dump_one_reg_file_fd(&p, vma_area->vm_file_fd, cr_fdset, 0);
 			if (ret)
 				goto err;
 		}