fsck: look for fsck binary not just in /sbin

This removes remaining hardcoded occurences of `/sbin/fsck`, and instead
uses `find_executable` to find `fsck`.

We also use `fsck_exists_for_fstype` to check for the `fsck.*`
executable, which also checks in `$PATH`, so it's fair to assume fsck
itself is also available.

1 files changed, 11 insertions, 2 deletions

diff --git a/src/shared/dissect-image.c b/src/shared/dissect-image.c
index 46c42cfc95..b7c049e4c3 100644
--- a/src/shared/dissect-image.c
+++ b/src/shared/dissect-image.c
@@ -1693,6 +1693,7 @@ static int is_loop_device(const char *path) {
 static int run_fsck(int node_fd, const char *fstype) {
         int r, exit_status;
         pid_t pid;
+        _cleanup_free_ char *fsck_path = NULL;
 
         assert(node_fd >= 0);
         assert(fstype);
@@ -1707,6 +1708,14 @@ static int run_fsck(int node_fd, const char *fstype) {
                 return 0;
         }
 
+        r = find_executable("fsck", &fsck_path);
+        /* We proceed anyway if we can't determine whether the fsck
+         * binary for some specific fstype exists,
+         * but the lack of the main fsck binary should be considered
+         * an error. */
+        if (r < 0)
+                return log_error_errno(r, "Cannot find fsck binary: %m");
+
         r = safe_fork_full(
                         "(fsck)",
                         NULL,
@@ -1717,7 +1726,7 @@ static int run_fsck(int node_fd, const char *fstype) {
                 return log_debug_errno(r, "Failed to fork off fsck: %m");
         if (r == 0) {
                 /* Child */
-                execl("/sbin/fsck", "/sbin/fsck", "-aT", FORMAT_PROC_FD_PATH(node_fd), NULL);
+                execl(fsck_path, fsck_path, "-aT", FORMAT_PROC_FD_PATH(node_fd), NULL);
                 log_open();
                 log_debug_errno(errno, "Failed to execl() fsck: %m");
                 _exit(FSCK_OPERATIONAL_ERROR);
@@ -1725,7 +1734,7 @@ static int run_fsck(int node_fd, const char *fstype) {
 
         exit_status = wait_for_terminate_and_check("fsck", pid, 0);
         if (exit_status < 0)
-                return log_debug_errno(exit_status, "Failed to fork off /sbin/fsck: %m");
+                return log_debug_errno(exit_status, "Failed to fork off %s: %m", fsck_path);
 
         if ((exit_status & ~FSCK_ERROR_CORRECTED) != FSCK_SUCCESS) {
                 log_debug("fsck failed with exit status %i.", exit_status);