diff options
| -rw-r--r-- | libmount/src/context_loopdev.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/libmount/src/context_loopdev.c b/libmount/src/context_loopdev.c index d32e70966..226b562c4 100644 --- a/libmount/src/context_loopdev.c +++ b/libmount/src/context_loopdev.c @@ -22,6 +22,7 @@ int mnt_context_is_loopdev(struct libmnt_context *cxt) const char *type, *src; assert(cxt); + /* The mount flags have to be merged, otherwise we have to use * expensive mnt_context_get_user_mflags() instead of cxt->user_mountflags. */ assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED)); @@ -35,15 +36,20 @@ int mnt_context_is_loopdev(struct libmnt_context *cxt) if (cxt->user_mountflags & (MNT_MS_LOOP | MNT_MS_OFFSET | MNT_MS_SIZELIMIT | - MNT_MS_ENCRYPTION)) + MNT_MS_ENCRYPTION)) { + + DBG(CXT, mnt_debug_h(cxt, "loopdev specific options detected")); return 1; + } if (cxt->mountflags & (MS_BIND | MS_MOVE | MS_PROPAGATION)) return 0; - /* Automatically create a loop device from a regular file if a filesystem - * is not specified or the filesystem is known for libblkid (these - * filesystems work with block devices only). + /* Automatically create a loop device from a regular file if a + * filesystem is not specified or the filesystem is known for libblkid + * (these filesystems work with block devices only). The file size + * should be at least 1KiB otherwise we will create empty loopdev where + * is no mountable filesystem... * * Note that there is not a restriction (on kernel side) that prevents regular * file as a mount(2) source argument. A filesystem that is able to mount @@ -55,11 +61,12 @@ int mnt_context_is_loopdev(struct libmnt_context *cxt) (!type || strcmp(type, "auto") == 0 || blkid_known_fstype(type))) { struct stat st; - if (stat(src, &st) || !S_ISREG(st.st_mode)) - return 0; + if (stat(src, &st) == 0 && S_ISREG(st.st_mode) && + st.st_size > 1024) + return 1; } - return 1; + return 0; } int mnt_context_setup_loopdev(struct libmnt_context *cxt) |