On 2018-05-17 17:31, Ondrej Mosnacek wrote: > 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 incorrect also because it compared > to cred->fsgid and not cred->gid. > > GitHub issue: > https://github.com/linux-audit/audit-kernel/issues/82 > > Fixes: 37eebe39c973 ("audit: improve GID/EGID comparation logic") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> Nice. You found a function that let you not have to roll a new global one. Is the comparision with cred->fsgid important? If you run ./scripts/checkpatch.pl on the patch file it will complain on those lines longer than 80 chars. I don't have a problem with it. > --- > kernel/auditsc.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index cbab0da86d15..ec38e4d97c23 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: > -- > 2.17.0 > - RGB -- Richard Guy Briggs <rgb@xxxxxxxxxx> Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada IRC: rgb, SunRaycer Voice: +1.647.777.2635, Internal: (81) 32635
