systemd/SOURCES/0466-udev-add-new-builtin-net_driver.patch

From f2bf171137c348f6f976276504c8e8a54e33ff78 Mon Sep 17 00:00:00 2001
From: Lukas Nykryn <lnykryn@redhat.com>
Date: Thu, 19 Oct 2023 10:38:06 +0200
Subject: [PATCH] udev: add new builtin net_driver

Currently the ID_NET_DRIVER is set in net_setup_link builtin.
But this is called pretty late in the udev processing chain.

Right now in some custom rules it was workarounded by calling ethtool
binary directly, which is ugly.

So let's split this code to a separate builtin.

(cherry picked from commit 2b5b25f123ceb89b3ff45b2380db1c8a88b046d9)

Resolves: RHEL-22443
---
 rules.d/50-udev-default.rules.in       |  2 ++
 src/udev/meson.build                   |  1 +
 src/udev/net/link-config.c             |  5 ++-
 src/udev/net/link-config.h             |  2 +-
 src/udev/udev-builtin-net_driver.c     | 43 ++++++++++++++++++++++++++
 src/udev/udev-builtin-net_setup_link.c |  3 --
 src/udev/udev-builtin.c                |  1 +
 src/udev/udev-builtin.h                |  2 ++
 8 files changed, 52 insertions(+), 7 deletions(-)
 create mode 100644 src/udev/udev-builtin-net_driver.c

diff --git a/rules.d/50-udev-default.rules.in b/rules.d/50-udev-default.rules.in
index 843bdaf9ce..f670b51987 100644
--- a/rules.d/50-udev-default.rules.in
+++ b/rules.d/50-udev-default.rules.in
@@ -17,6 +17,8 @@ SUBSYSTEM=="rtc", KERNEL=="rtc0", SYMLINK+="rtc", OPTIONS+="link_priority=-100"
 SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", IMPORT{builtin}="usb_id", IMPORT{builtin}="hwdb --subsystem=usb"
 ENV{MODALIAS}!="", IMPORT{builtin}="hwdb --subsystem=$env{SUBSYSTEM}"
 
+SUBSYSTEM=="net", IMPORT{builtin}="net_driver"
+
 ACTION!="add", GOTO="default_end"
 
 SUBSYSTEM=="tty", KERNEL=="ptmx", GROUP="tty", MODE="0666"
diff --git a/src/udev/meson.build b/src/udev/meson.build
index 08a1d97e81..564aa6de1b 100644
--- a/src/udev/meson.build
+++ b/src/udev/meson.build
@@ -35,6 +35,7 @@ libudevd_core_sources = files(
         'udev-builtin-hwdb.c',
         'udev-builtin-input_id.c',
         'udev-builtin-keyboard.c',
+        'udev-builtin-net_driver.c',
         'udev-builtin-net_id.c',
         'udev-builtin-net_setup_link.c',
         'udev-builtin-path_id.c',
diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c
index 2d8c902fd3..80c64519ab 100644
--- a/src/udev/net/link-config.c
+++ b/src/udev/net/link-config.c
@@ -362,7 +362,6 @@ Link *link_free(Link *link) {
 
         sd_device_unref(link->device);
         free(link->kind);
-        free(link->driver);
         strv_free(link->altnames);
         return mfree(link);
 }
@@ -415,8 +414,8 @@ int link_new(LinkConfigContext *ctx, sd_netlink **rtnl, sd_device *device, Link
                         log_link_debug_errno(link, r, "Failed to get permanent hardware address, ignoring: %m");
         }
 
-        r = ethtool_get_driver(&ctx->ethtool_fd, link->ifname, &link->driver);
-        if (r < 0)
+        r = sd_device_get_property_value(link->device, "ID_NET_DRIVER", &link->driver);
+        if (r < 0 && r != -ENOENT)
                 log_link_debug_errno(link, r, "Failed to get driver, ignoring: %m");
 
         *ret = TAKE_PTR(link);
diff --git a/src/udev/net/link-config.h b/src/udev/net/link-config.h
index 874a391543..8343783caf 100644
--- a/src/udev/net/link-config.h
+++ b/src/udev/net/link-config.h
@@ -34,7 +34,7 @@ typedef struct Link {
         sd_device_action_t action;
 
         char *kind;
-        char *driver;
+        const char *driver;
         uint16_t iftype;
         uint32_t flags;
         struct hw_addr_data hw_addr;
diff --git a/src/udev/udev-builtin-net_driver.c b/src/udev/udev-builtin-net_driver.c
new file mode 100644
index 0000000000..f1642a491d
--- /dev/null
+++ b/src/udev/udev-builtin-net_driver.c
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "alloc-util.h"
+#include "device-util.h"
+#include "errno-util.h"
+#include "ethtool-util.h"
+#include "fd-util.h"
+#include "log.h"
+#include "string-util.h"
+#include "udev-builtin.h"
+
+static int builtin_net_driver_set_driver(UdevEvent *event, int argc, char **argv, bool test) {
+        sd_device *dev = ASSERT_PTR(ASSERT_PTR(event)->dev);
+        _cleanup_close_ int ethtool_fd = -EBADF;
+        _cleanup_free_ char *driver = NULL;
+        const char *sysname;
+        int r;
+
+        r = sd_device_get_sysname(dev, &sysname);
+        if (r < 0)
+                return log_device_warning_errno(dev, r, "Failed to get sysname: %m");
+
+        r = ethtool_get_driver(&ethtool_fd, sysname, &driver);
+        if (ERRNO_IS_NEG_NOT_SUPPORTED(r)) {
+                log_device_debug_errno(dev, r, "Querying driver name via ethtool API is not supported by device '%s', ignoring: %m", sysname);
+                return 0;
+        }
+        if (r == -ENODEV) {
+                log_device_debug_errno(dev, r, "Device already vanished, ignoring.");
+                return 0;
+        }
+        if (r < 0)
+                return log_device_warning_errno(dev, r, "Failed to get driver for '%s': %m", sysname);
+
+        return udev_builtin_add_property(event->dev, test, "ID_NET_DRIVER", driver);
+}
+
+const UdevBuiltin udev_builtin_net_driver = {
+        .name = "net_driver",
+        .cmd = builtin_net_driver_set_driver,
+        .help = "Set driver for network device",
+        .run_once = true,
+};
diff --git a/src/udev/udev-builtin-net_setup_link.c b/src/udev/udev-builtin-net_setup_link.c
index e964bf7bf4..b0279a1814 100644
--- a/src/udev/udev-builtin-net_setup_link.c
+++ b/src/udev/udev-builtin-net_setup_link.c
@@ -26,9 +26,6 @@ static int builtin_net_setup_link(UdevEvent *event, int argc, char **argv, bool
         if (r < 0)
                 return log_device_warning_errno(dev, r, "Failed to get link information: %m");
 
-        if (link->driver)
-                udev_builtin_add_property(dev, test, "ID_NET_DRIVER", link->driver);
-
         r = link_get_config(ctx, link);
         if (r < 0) {
                 if (r == -ENOENT) {
diff --git a/src/udev/udev-builtin.c b/src/udev/udev-builtin.c
index c84db8855c..d55dc3337d 100644
--- a/src/udev/udev-builtin.c
+++ b/src/udev/udev-builtin.c
@@ -22,6 +22,7 @@ static const UdevBuiltin *const builtins[_UDEV_BUILTIN_MAX] = {
 #if HAVE_KMOD
         [UDEV_BUILTIN_KMOD] = &udev_builtin_kmod,
 #endif
+        [UDEV_BUILTIN_NET_DRIVER] = &udev_builtin_net_driver,
         [UDEV_BUILTIN_NET_ID] = &udev_builtin_net_id,
         [UDEV_BUILTIN_NET_LINK] = &udev_builtin_net_setup_link,
         [UDEV_BUILTIN_PATH_ID] = &udev_builtin_path_id,
diff --git a/src/udev/udev-builtin.h b/src/udev/udev-builtin.h
index 919d51e798..c23f2d1613 100644
--- a/src/udev/udev-builtin.h
+++ b/src/udev/udev-builtin.h
@@ -19,6 +19,7 @@ typedef enum UdevBuiltinCommand {
 #if HAVE_KMOD
         UDEV_BUILTIN_KMOD,
 #endif
+        UDEV_BUILTIN_NET_DRIVER,
         UDEV_BUILTIN_NET_ID,
         UDEV_BUILTIN_NET_LINK,
         UDEV_BUILTIN_PATH_ID,
@@ -63,6 +64,7 @@ extern const UdevBuiltin udev_builtin_keyboard;
 #if HAVE_KMOD
 extern const UdevBuiltin udev_builtin_kmod;
 #endif
+extern const UdevBuiltin udev_builtin_net_driver;
 extern const UdevBuiltin udev_builtin_net_id;
 extern const UdevBuiltin udev_builtin_net_setup_link;
 extern const UdevBuiltin udev_builtin_path_id;