From 5845b46ba3883fe0b21217c65f41383eb52cddb6 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 20 Aug 2010 04:04:05 +0200 Subject: [PATCH] device: handle properly if two devices want to have the same name https://bugzilla.redhat.com/show_bug.cgi?id=624539 --- src/device.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/src/device.c b/src/device.c index 8074a3edd..bf032d0ce 100644 --- a/src/device.c +++ b/src/device.c @@ -188,12 +188,12 @@ static int device_update_unit(Manager *m, struct udev_device *dev, const char *p if ((r = device_find_escape_name(m, path, &u)) < 0) return r; - /* If this is a different unit, then let's not merge things */ - if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs)) { - log_error("Hmm, something's broken. Asked to create two devices with same name but different sysfs paths. (%s vs %s)", - DEVICE(u)->sysfs, sysfs); + /* If a different unit already claimed this name then let's do + * nothing. This can happen for example when two disks with + * the same label are plugged in, and which hence try to get + * conflicting symlinks in /dev/disk/by-label/xxxx */ + if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs)) return -EEXIST; - } if (!u) { delete = true; @@ -308,6 +308,7 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u first = udev_device_get_devlinks_list_entry(dev); udev_list_entry_foreach(item, first) { const char *p; + struct stat st; /* Don't bother with the /dev/block links */ p = udev_list_entry_get_name(item); @@ -316,6 +317,18 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u path_startswith(p, "/dev/char/")) continue; + /* Verify that the symlink in the FS actually belongs + * to this device. This is useful to deal with + * conflicting devices, e.g. when two disks want the + * same /dev/disk/by-label/xxx link because they have + * the same label. We want to make sure that the same + * device that won the symlink wins in systemd, so we + * check the device node major/minor*/ + if (stat(p, &st) >= 0) + if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) || + st.st_rdev != udev_device_get_devnum(dev)) + continue; + device_update_unit(m, dev, p, false); } -- 2.30.2