1 files changed, 16 insertions, 15 deletions

diff --git a/src/basic/fd-util.c b/src/basic/fd-util.c
index e085dc23b4..c06f2fac7e 100644
--- a/src/basic/fd-util.c
+++ b/src/basic/fd-util.c
@@ -23,6 +23,7 @@
 #include "socket-util.h"
 #include "stdio-util.h"
 #include "util.h"
+#include "tmpfile-util.h"
 
 int close_nointr(int fd) {
         assert(fd >= 0);
@@ -113,7 +114,7 @@ FILE* safe_fclose(FILE *f) {
         if (f) {
                 PROTECT_ERRNO;
 
-                assert_se(fclose_nointr(f) != EBADF);
+                assert_se(fclose_nointr(f) != -EBADF);
         }
 
         return NULL;
@@ -277,7 +278,7 @@ int same_fd(int a, int b) {
                 return true;
         if (r > 0)
                 return false;
-        if (errno != ENOSYS)
+        if (!IN_SET(errno, ENOSYS, EACCES, EPERM))
                 return -errno;
 
         /* We don't have kcmp(), use fstat() instead. */
@@ -353,22 +354,22 @@ bool fdname_is_valid(const char *s) {
 }
 
 int fd_get_path(int fd, char **ret) {
-        _cleanup_close_ int dir = -1;
-        char fdname[DECIMAL_STR_MAX(int)];
+        char procfs_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)];
         int r;
 
-        dir = open("/proc/self/fd/", O_CLOEXEC | O_DIRECTORY | O_PATH);
-        if (dir < 0)
-                /* /proc is not available or not set up properly, we're most likely
-                 * in some chroot environment. */
-                return errno == ENOENT ? -EOPNOTSUPP : -errno;
+        xsprintf(procfs_path, "/proc/self/fd/%i", fd);
+        r = readlink_malloc(procfs_path, ret);
+        if (r == -ENOENT) {
+                /* ENOENT can mean two things: that the fd does not exist or that /proc is not mounted. Let's make
+                 * things debuggable and distuingish the two. */
 
-        xsprintf(fdname, "%i", fd);
+                if (access("/proc/self/fd/", F_OK) < 0)
+                        /* /proc is not available or not set up properly, we're most likely in some chroot
+                         * environment. */
+                        return errno == ENOENT ? -EOPNOTSUPP : -errno;
 
-        r = readlinkat_malloc(dir, fdname, ret);
-        if (r == -ENOENT)
-                /* If the file doesn't exist the fd is invalid */
-                return -EBADF;
+                return -EBADF; /* The directory exists, hence it's the fd that doesn't. */
+        }
 
         return r;
 }
@@ -648,7 +649,7 @@ int fd_duplicate_data_fd(int fd) {
 
                         if ((size_t) isz >= DATA_FD_MEMORY_LIMIT) {
 
-                                r = copy_bytes_full(fd, pipefds[1], DATA_FD_MEMORY_LIMIT, 0, &remains, &remains_size);
+                                r = copy_bytes_full(fd, pipefds[1], DATA_FD_MEMORY_LIMIT, 0, &remains, &remains_size, NULL, NULL);
                                 if (r < 0 && r != -EAGAIN)
                                         return r; /* If we get EAGAIN it could be because of the source or because of
                                                    * the destination fd, we can't know, as sendfile() and friends won't