From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Wed, 2 Jul 2025 23:15:51 +0000 (+0900)
Subject: udev-builtin-uaccess: open device node with O_PATH
X-Git-Tag: v258-rc1~200
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=aada48970ed9d606331e636dab7da0ca520a5bdf;p=thirdparty%2Fsystemd.git

udev-builtin-uaccess: open device node with O_PATH

Some device node refuses to be opened with read-write mode.
Let's not open with O_RDWR, but open with O_PATH, and use
FORMAT_PROC_FD_PATH().

Follow-up for 1abb592f2f886913492e4967cc96816c167177a9.

Fixes #38033.
---

diff --git a/src/udev/udev-builtin-uaccess.c b/src/udev/udev-builtin-uaccess.c
index 9a9ba43b1c9..bd2f77c69d6 100644
--- a/src/udev/udev-builtin-uaccess.c
+++ b/src/udev/udev-builtin-uaccess.c
@@ -19,7 +19,7 @@ static int devnode_acl(int fd, uid_t uid) {
         assert(fd >= 0);
 
         _cleanup_(acl_freep) acl_t acl = NULL;
-        acl = acl_get_fd(fd);
+        acl = acl_get_file(FORMAT_PROC_FD_PATH(fd), ACL_TYPE_ACCESS);
         if (!acl)
                 return -errno;
 
@@ -99,7 +99,7 @@ static int devnode_acl(int fd, uid_t uid) {
         if (acl_calc_mask(&acl) < 0)
                 return -errno;
 
-        if (acl_set_fd(fd, acl) < 0)
+        if (acl_set_file(FORMAT_PROC_FD_PATH(fd), ACL_TYPE_ACCESS, acl) < 0)
                 return -errno;
 
         return 0;
@@ -120,7 +120,7 @@ static int builtin_uaccess(UdevEvent *event, int argc, char *argv[]) {
         if (!logind_running())
                 return 0;
 
-        _cleanup_close_ int fd = sd_device_open(dev, O_CLOEXEC|O_RDWR);
+        _cleanup_close_ int fd = sd_device_open(dev, O_CLOEXEC|O_PATH);
         if (fd < 0)
                 return log_device_error_errno(dev, fd, "Failed to open device node: %m");