[pbs-devel] [PATCH proxmox-backup] fix 5304: client: set process uid/gid for .pxarexclude-cli

[Christian Ebner]

The .pxarexclude-cli encodes the exclude patterns the client was
invoked with in the pxar archive as regular file entry. The current
behaviour of setting the uid and gid to default 0 (root) causes
however issues when trying to backup and restore the backup as
non-root user.

Opt for using the uid/gid of the user the executable was called as,
allowing the restore for this user to succeed. Root will succeed
to restore anyways.

Link to issue in bugtracker:
https://bugzilla.proxmox.com/show_bug.cgi?id=5304

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
 pbs-client/src/pxar/create.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pbs-client/src/pxar/create.rs b/pbs-client/src/pxar/create.rs
index 60efb0ce5..a5afde7af 100644
--- a/pbs-client/src/pxar/create.rs
+++ b/pbs-client/src/pxar/create.rs
@@ -404,6 +404,10 @@ impl Archiver {
 
         let mut metadata = Metadata::default();
         metadata.stat.mode = pxar::format::mode::IFREG | 0o600;
+        // use uid/gid of client process so the backup snapshot might be restored by the same
+        // potentially non-root user
+        metadata.stat.uid = unsafe { libc::getuid() };
+        metadata.stat.gid = unsafe { libc::getgid() };
 
         let mut file = encoder
             .create_file(&metadata, ".pxarexclude-cli", content.len() as u64)
-- 
2.39.2