[CRIU] [PATCH 1/2] bfd: Don't leak image-open flags into bfdopen

[Pavel Emelyanov]

Signed-off-by: Pavel Emelyanov <xemul at parallels.com>
---
 bfd.c         | 16 +++++++++++++---
 image.c       | 11 +++++++++--
 include/bfd.h |  5 +++--
 proc_parse.c  |  8 ++++----
 4 files changed, 29 insertions(+), 11 deletions(-)

diff --git a/bfd.c b/bfd.c
index 9ebffc4..d63b3e0 100644
--- a/bfd.c
+++ b/bfd.c
@@ -87,17 +87,27 @@ static void buf_put(struct xbuf *xb)
 	xb->data = NULL;
 }
 
-int bfdopen(struct bfd *f, int mode)
+static int bfdopen(struct bfd *f, bool writable)
 {
 	if (buf_get(&f->b)) {
 		close(f->fd);
 		return -1;
 	}
 
-	f->mode = mode;
+	f->writable = writable;
 	return 0;
 }
 
+int bfdopenr(struct bfd *f)
+{
+	return bfdopen(f, false);
+}
+
+int bfdopenw(struct bfd *f)
+{
+	return bfdopen(f, true);
+}
+
 static int bflush(struct bfd *bfd);
 static bool flush_failed = false;
 
@@ -109,7 +119,7 @@ int bfd_flush_images(void)
 void bclose(struct bfd *f)
 {
 	if (bfd_buffered(f)) {
-		if ((f->mode != O_RDONLY) && bflush(f) < 0) {
+		if (f->writable && bflush(f) < 0) {
 			/*
 			 * This is to propagate error up. It's
 			 * hardly possible by returning and
diff --git a/image.c b/image.c
index 9de88cb..106c283 100644
--- a/image.c
+++ b/image.c
@@ -239,8 +239,15 @@ struct cr_img *open_image_at(int dfd, int type, unsigned long flags, ...)
 	img->_x.fd = ret;
 	if (oflags & O_NOBUF)
 		bfd_setraw(&img->_x);
-	else if (bfdopen(&img->_x, flags))
-		goto err_close;
+	else {
+		if (flags == O_RDONLY)
+			ret = bfdopenr(&img->_x);
+		else
+			ret = bfdopenw(&img->_x);
+
+		if (ret)
+			goto err_close;
+	}
 
 	if (imgset_template[type].magic == RAW_IMAGE_MAGIC)
 		goto skip_magic;
diff --git a/include/bfd.h b/include/bfd.h
index cd2f4ad..1dd1ea2 100644
--- a/include/bfd.h
+++ b/include/bfd.h
@@ -13,7 +13,7 @@ struct xbuf {
 
 struct bfd {
 	int fd;
-	int mode;
+	bool writable;
 	struct xbuf b;
 };
 
@@ -27,7 +27,8 @@ static inline void bfd_setraw(struct bfd *b)
 	b->b.mem = NULL;
 }
 
-int bfdopen(struct bfd *f, int mode);
+int bfdopenr(struct bfd *f);
+int bfdopenw(struct bfd *f);
 void bclose(struct bfd *f);
 char *breadline(struct bfd *f);
 int bwrite(struct bfd *f, const void *buf, int sz);
diff --git a/proc_parse.c b/proc_parse.c
index c8034c1..8ad9d21 100644
--- a/proc_parse.c
+++ b/proc_parse.c
@@ -358,7 +358,7 @@ int parse_smaps(pid_t pid, struct vm_area_list *vma_area_list)
 	if (f.fd < 0)
 		goto err_n;
 
-	if (bfdopen(&f, O_RDONLY))
+	if (bfdopenr(&f))
 		goto err_n;
 
 	map_files_dir = opendir_proc(pid, "map_files");
@@ -733,7 +733,7 @@ int parse_pid_status(pid_t pid, struct proc_status_creds *cr)
 		return -1;
 	}
 
-	if (bfdopen(&f, O_RDONLY))
+	if (bfdopenr(&f))
 		return -1;
 
 	while (done < 8 && (str = breadline(&f))) {
@@ -1165,7 +1165,7 @@ static int parse_fdinfo_pid_s(int pid, int fd, int type,
 		return -1;
 	}
 
-	if (bfdopen(&f, O_RDONLY))
+	if (bfdopenr(&f))
 		return -1;
 
 	while (1) {
@@ -1616,7 +1616,7 @@ int parse_posix_timers(pid_t pid, struct proc_posix_timers_stat *args)
 		return -1;
 	}
 
-	if (bfdopen(&f, O_RDONLY))
+	if (bfdopenr(&f))
 		return -1;
 
 	while (1) {
-- 
1.8.4.2