cleanup appimage

1 files changed, 32 insertions, 22 deletions

diff --git a/src/firejail/appimage.c b/src/firejail/appimage.c
index f93891af2..a4f727c0a 100644
--- a/src/firejail/appimage.c
+++ b/src/firejail/appimage.c
@@ -33,12 +33,10 @@ static char *devloop = NULL;	// device file
 static long unsigned size = 0;  // offset into appimage file
 #define MAXBUF 4096
 
-#ifdef LOOP_CTL_GET_FREE        // test for older kernels; this definition is found in /usr/include/linux/loop.h
-static void err_loop(void) {
-        fprintf(stderr, "Error: cannot configure loopback device\n");
+static void err_loop(char *msg) {
+        fprintf(stderr, "%s\n", msg);
         exit(1);
 }
-#endif
 
 // return 1 if found
 int appimage_find_profile(const char *archive) {
@@ -75,7 +73,6 @@ void appimage_set(const char *appimage) {
         assert(devloop == NULL);        // don't call this twice!
         EUID_ASSERT();
 
-#ifdef LOOP_CTL_GET_FREE
         // open appimage file
         invalid_filename(appimage, 0); // no globbing
         int ffd = open(appimage, O_RDONLY|O_CLOEXEC);
@@ -99,29 +96,46 @@ void appimage_set(const char *appimage) {
 
         // find or allocate a free loop device to use
         EUID_ROOT();
-        int cfd = open("/dev/loop-control", O_RDWR|O_CLOEXEC);
-        if (cfd == -1)
-                err_loop();
-        int devnr = ioctl(cfd, LOOP_CTL_GET_FREE);
-        if (devnr == -1)
-                err_loop();
+        int cfd; // loop control fd
+        if ((cfd = open("/dev/loop-control", O_RDWR|O_CLOEXEC)) == -1) {
+                sleep(1); // sleep 1 second and try again
+                if ((cfd = open("/dev/loop-control", O_RDWR|O_CLOEXEC)) == -1)
+                        err_loop("cannot open /dev/loop-control");
+        }
+
+        int devnr; // loop device number
+        if ((devnr = ioctl(cfd, LOOP_CTL_GET_FREE)) == -1) {
+                sleep(1); // sleep 1 second and try again
+                if ((devnr = ioctl(cfd, LOOP_CTL_GET_FREE)) == -1)
+                        err_loop("cannot get a free loop device number");
+        }
         close(cfd);
         if (asprintf(&devloop, "/dev/loop%d", devnr) == -1)
                 errExit("asprintf");
 
+        int lfd; // loopback fd
+        if ((lfd = open(devloop, O_RDONLY|O_CLOEXEC)) == -1) {
+                sleep (1); // sleep 1 second and try again
+                if ((lfd = open(devloop, O_RDONLY|O_CLOEXEC)) == -1)
+                        err_loop("cannot open loop device");
+        }
+
         // associate loop device with appimage
-        int lfd = open(devloop, O_RDONLY|O_CLOEXEC);
-        if (lfd == -1)
-                err_loop();
-        if (ioctl(lfd, LOOP_SET_FD, ffd) == -1)
-                err_loop();
+        if (ioctl(lfd, LOOP_SET_FD, ffd) == -1) {
+                sleep(1); // sleep 1 second and try again
+                if (ioctl(lfd, LOOP_SET_FD, ffd) == -1)
+                        err_loop("cannot associate loop device with appimage file");
+        }
 
         if (size) {
                 struct loop_info64 info;
                 memset(&info, 0, sizeof(struct loop_info64));
                 info.lo_offset = size;
-                if (ioctl(lfd,  LOOP_SET_STATUS64, &info) == -1)
-                        err_loop();
+                if (ioctl(lfd,  LOOP_SET_STATUS64, &info) == -1) {
+                        sleep(1); // sleep 1 second and try again
+                        if (ioctl(lfd,  LOOP_SET_STATUS64, &info) == -1)
+                                err_loop("cannot set loop status");
+                }
         }
         close(lfd);
         close(ffd);
@@ -143,10 +157,6 @@ void appimage_set(const char *appimage) {
                 env_store_name_val("OWD", cfg.cwd, SETENV);
 
         __gcov_flush();
-#else
-        fprintf(stderr, "Error: /dev/loop-control interface is not supported by your kernel\n");
-        exit(1);
-#endif
 }
 
 // mount appimage into sandbox file system