From 976c0478410d3bac9d11278ed024a3cdb1bef749 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 1 Dec 2017 12:59:16 +0100 Subject: [PATCH] mount-util: tape over name_to_handle_at() flakiness (#7517) Apparently, the kernel returns EINVAL on NFS4 sometimes, even if we do everything right, let's fallback in that case and find a different approach to determine if something's a mount point. See discussion at: https://github.com/systemd/systemd/issues/7082#issuecomment-348001289 --- src/basic/mount-util.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/src/basic/mount-util.c b/src/basic/mount-util.c index e32502308a..e394e1adf3 100644 --- a/src/basic/mount-util.c +++ b/src/basic/mount-util.c @@ -183,10 +183,11 @@ int fd_is_mount_point(int fd, const char *filename, int flags) { * real mounts of their own. */ r = name_to_handle_at_loop(fd, filename, &h, &mount_id, flags); - if (IN_SET(r, -ENOSYS, -EACCES, -EPERM, -EOVERFLOW)) + if (IN_SET(r, -ENOSYS, -EACCES, -EPERM, -EOVERFLOW, -EINVAL)) /* This kernel does not support name_to_handle_at() at all (ENOSYS), or the syscall was blocked * (EACCES/EPERM; maybe through seccomp, because we are running inside of a container?), or the mount - * point is not triggered yet (EOVERFLOW, thinkg nfs4): fall back to simpler logic. */ + * point is not triggered yet (EOVERFLOW, think nfs4), or some general name_to_handle_at() flakiness + * (EINVAL): fall back to simpler logic. */ goto fallback_fdinfo; else if (r == -EOPNOTSUPP) /* This kernel or file system does not support name_to_handle_at(), hence let's see if the upper fs @@ -308,7 +309,7 @@ int path_get_mnt_id(const char *path, int *ret) { int r; r = name_to_handle_at_loop(AT_FDCWD, path, NULL, ret, 0); - if (IN_SET(r, -EOPNOTSUPP, -ENOSYS, -EACCES, -EPERM, -EOVERFLOW)) /* kernel/fs don't support this, or seccomp blocks access, or untriggered mount */ + if (IN_SET(r, -EOPNOTSUPP, -ENOSYS, -EACCES, -EPERM, -EOVERFLOW, -EINVAL)) /* kernel/fs don't support this, or seccomp blocks access, or untriggered mount, or name_to_handle_at() is flaky */ return fd_fdinfo_mnt_id(AT_FDCWD, path, 0, ret); return r;