tree-wide: drop acquire_data_fd_full() helper

Let's drop support systems lacking memfds, i.e. pre kernel 3.17 systems. This allows us to drastically simplify the "data fd" concept, so far that we can remove it entirely. This replaces acquire_data_fd() with a specialized call to memfd_new_and_seal(), not that memfds can be the only implementation of the concept.
yuwata · Dec 17, 2024 · a87a962 · a87a962
1 parent 8d08f18
commit a87a962
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Showing 14 changed files with 65 additions and 289 deletions.
diff --git a/src/basic/memfd-util.c b/src/basic/memfd-util.c
@@ -177,6 +177,9 @@ int memfd_new_and_seal(const char *name, const void *data, size_t sz) {
 
         assert(data || sz == 0);
 
+        if (sz == SIZE_MAX)
+                sz = strlen(data);
+
         fd = memfd_new(name);
         if (fd < 0)
                 return fd;

diff --git a/src/basic/memfd-util.h b/src/basic/memfd-util.h
@@ -11,6 +11,9 @@ int memfd_create_wrapper(const char *name, unsigned mode);
 int memfd_new(const char *name);
 int memfd_new_and_map(const char *name, size_t sz, void **p);
 int memfd_new_and_seal(const char *name, const void *data, size_t sz);
+static inline int memfd_new_and_seal_string(const char *name, const char *s) {
+        return memfd_new_and_seal(name, s, SIZE_MAX);
+}
 
 int memfd_add_seals(int fd, unsigned int seals);
 int memfd_get_seals(int fd, unsigned int *ret_seals);

diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c
@@ -14,7 +14,6 @@
 #include "bus-util.h"
 #include "chase.h"
 #include "confidential-virt.h"
-#include "data-fd-util.h"
 #include "dbus-cgroup.h"
 #include "dbus-execute.h"
 #include "dbus-job.h"
@@ -33,6 +32,7 @@
 #include "locale-util.h"
 #include "log.h"
 #include "manager-dump.h"
+#include "memfd-util.h"
 #include "os-util.h"
 #include "parse-util.h"
 #include "path-util.h"
@@ -1447,7 +1447,7 @@ static int method_dump(sd_bus_message *message, void *userdata, sd_bus_error *er
 static int reply_dump_by_fd(sd_bus_message *message, char *dump) {
         _cleanup_close_ int fd = -EBADF;
 
-        fd = acquire_data_fd(dump);
+        fd = memfd_new_and_seal_string("dump", dump);
         if (fd < 0)
                 return fd;
 

diff --git a/src/core/exec-invoke.c b/src/core/exec-invoke.c
@@ -31,7 +31,6 @@
 #include "chattr-util.h"
 #include "chown-recursive.h"
 #include "copy.h"
-#include "data-fd-util.h"
 #include "env-util.h"
 #include "escape.h"
 #include "exec-credential.h"
@@ -44,6 +43,7 @@
 #include "io-util.h"
 #include "iovec-util.h"
 #include "journal-send.h"
+#include "memfd-util.h"
 #include "missing_ioprio.h"
 #include "missing_prctl.h"
 #include "missing_sched.h"
@@ -406,7 +406,7 @@ static int setup_input(
         case EXEC_INPUT_DATA: {
                 int fd;
 
-                fd = acquire_data_fd_full(context->stdin_data, context->stdin_data_size, /* flags = */ 0);
+                fd = memfd_new_and_seal("exec-input", context->stdin_data, context->stdin_data_size);
                 if (fd < 0)
                         return fd;
 

diff --git a/src/home/homed-home.c b/src/home/homed-home.c
@@ -13,7 +13,6 @@
 #include "build-path.h"
 #include "bus-common-errors.h"
 #include "bus-locator.h"
-#include "data-fd-util.h"
 #include "env-util.h"
 #include "errno-list.h"
 #include "errno-util.h"
@@ -1266,7 +1265,7 @@ static int home_start_work(
         if (r < 0)
                 return r;
 
-        stdin_fd = acquire_data_fd(formatted);
+        stdin_fd = memfd_new_and_seal_string("request", formatted);
         if (stdin_fd < 0)
                 return stdin_fd;
 

diff --git a/src/home/homework-cifs.c b/src/home/homework-cifs.c
@@ -5,14 +5,14 @@
 #include <linux/fs.h>
 #endif
 
-#include "data-fd-util.h"
 #include "dirent-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "format-util.h"
 #include "fs-util.h"
 #include "homework-cifs.h"
 #include "homework-mount.h"
+#include "memfd-util.h"
 #include "mkdir.h"
 #include "mount-util.h"
 #include "process-util.h"
@@ -76,7 +76,7 @@ int home_setup_cifs(
                 pid_t mount_pid;
                 int exit_status;
 
-                passwd_fd = acquire_data_fd(*pw);
+                passwd_fd = memfd_new_and_seal_string("cifspw", *pw);
                 if (passwd_fd < 0)
                         return log_error_errno(passwd_fd, "Failed to create data FD for password: %m");
 

diff --git a/src/network/networkd-serialize.c b/src/network/networkd-serialize.c
@@ -2,11 +2,11 @@
 
 #include "af-list.h"
 #include "daemon-util.h"
-#include "data-fd-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "iovec-util.h"
 #include "json-util.h"
+#include "memfd-util.h"
 #include "networkd-address.h"
 #include "networkd-json.h"
 #include "networkd-link.h"
@@ -69,7 +69,7 @@ int manager_serialize(Manager *manager) {
                 return r;
 
         _cleanup_close_ int fd = -EBADF;
-        fd = acquire_data_fd(dump);
+        fd = memfd_new_and_seal_string("serialization", dump);
         if (fd < 0)
                 return fd;
 

diff --git a/src/oom/oomd-manager-bus.c b/src/oom/oomd-manager-bus.c
@@ -4,8 +4,8 @@
 
 #include "bus-common-errors.h"
 #include "bus-polkit.h"
-#include "data-fd-util.h"
 #include "fd-util.h"
+#include "memfd-util.h"
 #include "oomd-manager-bus.h"
 #include "oomd-manager.h"
 #include "user-util.h"
@@ -22,7 +22,7 @@ static int bus_method_dump_by_fd(sd_bus_message *message, void *userdata, sd_bus
         if (r < 0)
                 return r;
 
-        fd = acquire_data_fd(dump);
+        fd = memfd_new_and_seal_string("oomd-dump", dump);
         if (fd < 0)
                 return fd;
 

diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c
@@ -21,10 +21,10 @@
 #include "capsule-util.h"
 #include "chase.h"
 #include "daemon-util.h"
-#include "data-fd-util.h"
 #include "env-util.h"
 #include "fd-util.h"
 #include "format-util.h"
+#include "memfd-util.h"
 #include "memstream-util.h"
 #include "path-util.h"
 #include "socket-util.h"
@@ -803,7 +803,7 @@ static int method_dump_memory_state_by_fd(sd_bus_message *message, void *userdat
         if (r < 0)
                 return r;
 
-        fd = acquire_data_fd_full(dump, dump_size, /* flags = */ 0);
+        fd = memfd_new_and_seal("malloc-info", dump, dump_size);
         if (fd < 0)
                 return fd;