Vivek Goyal 449e8171f9 virtiofsd: Drop membership of all supplementary groups (CVE-2022-0358) ... At the start, drop membership of all supplementary groups. This is not required. If we have membership of "root" supplementary group and when we switch uid/gid using setresuid/setsgid, we still retain membership of existing supplemntary groups. And that can allow some operations which are not normally allowed. For example, if root in guest creates a dir as follows. $ mkdir -m 03777 test_dir This sets SGID on dir as well as allows unprivileged users to write into this dir. And now as unprivileged user open file as follows. $ su test $ fd = open("test_dir/priviledge_id", O_RDWR|O_CREAT|O_EXCL, 02755); This will create SGID set executable in test_dir/. And that's a problem because now an unpriviliged user can execute it, get egid=0 and get access to resources owned by "root" group. This is privilege escalation. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2044863 Fixes: CVE-2022-0358 Reported-by: JIETAO XIAO <shawtao1125@gmail.com> Suggested-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Message-Id: <YfBGoriS38eBQrAb@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: Fixed missing {}'s style nit		2022-01-26 10:32:05 +00:00
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ebpf	ebpf: Added eBPF RSS program.	2021-06-04 15:25:46 +08:00
virtiofsd	virtiofsd: Drop membership of all supplementary groups (CVE-2022-0358)	2022-01-26 10:32:05 +00:00
meson.build	virtiofsd: Allow to build it without the tools	2021-02-16 17:03:09 +00:00