From: Ondrej Mosnáček omosnace@redhat.com
[ Upstream commit af85d1772e31fed34165a1b3decef340cf4080c0 ]
The audit_filter_rules() function in auditsc.c used the in_[e]group_p() functions to check GID/EGID match, but these functions use the current task's credentials, while the comparison should use the credentials of the task given to audit_filter_rules() as a parameter (tsk).
Note that we can use group_search(cred->group_info, ...) as a replacement for both in_group_p and in_egroup_p as these functions only compare the parameter to cred->fsgid/egid and then call group_search.
In fact, the usage of in_group_p was even more incorrect: it compares to cred->fsgid (which is usually equal to cred->egid) and not cred->gid.
GitHub issue: https://github.com/linux-audit/audit-kernel/issues/82
Fixes: 37eebe39c973 ("audit: improve GID/EGID comparation logic") Signed-off-by: Ondrej Mosnacek omosnace@redhat.com Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- kernel/auditsc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 76d789d6cea0..bb861327f367 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -490,20 +490,20 @@ static int audit_filter_rules(struct task_struct *tsk, result = audit_gid_comparator(cred->gid, f->op, f->gid); if (f->op == Audit_equal) { if (!result) - result = in_group_p(f->gid); + result = groups_search(cred->group_info, f->gid); } else if (f->op == Audit_not_equal) { if (result) - result = !in_group_p(f->gid); + result = !groups_search(cred->group_info, f->gid); } break; case AUDIT_EGID: result = audit_gid_comparator(cred->egid, f->op, f->gid); if (f->op == Audit_equal) { if (!result) - result = in_egroup_p(f->gid); + result = groups_search(cred->group_info, f->gid); } else if (f->op == Audit_not_equal) { if (result) - result = !in_egroup_p(f->gid); + result = !groups_search(cred->group_info, f->gid); } break; case AUDIT_SGID: