From fcfe0ac2fcfae7d5fcad3d0375cb8ff38caf8aba Mon Sep 17 00:00:00 2001 From: Micah Morton Date: Wed, 8 Jun 2022 20:57:11 +0000 Subject: security: Add LSM hook to setgroups() syscall Give the LSM framework the ability to filter setgroups() syscalls. There are already analagous hooks for the set*uid() and set*gid() syscalls. The SafeSetID LSM will use this new hook to ensure setgroups() calls are allowed by the installed security policy. Tested by putting print statement in security_task_fix_setgroups() hook and confirming that it gets hit when userspace does a setgroups() syscall. Acked-by: Casey Schaufler Reviewed-by: Serge Hallyn Signed-off-by: Micah Morton --- kernel/groups.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'kernel') diff --git a/kernel/groups.c b/kernel/groups.c index 787b381c7c00..9aaed2a31073 100644 --- a/kernel/groups.c +++ b/kernel/groups.c @@ -134,13 +134,26 @@ EXPORT_SYMBOL(set_groups); int set_current_groups(struct group_info *group_info) { struct cred *new; + const struct cred *old; + int retval; new = prepare_creds(); if (!new) return -ENOMEM; + old = current_cred(); + set_groups(new, group_info); + + retval = security_task_fix_setgroups(new, old); + if (retval < 0) + goto error; + return commit_creds(new); + +error: + abort_creds(new); + return retval; } EXPORT_SYMBOL(set_current_groups); -- cgit v1.2.3