diff options
Diffstat (limited to 'sys/kern/kern_prot.c')
| -rw-r--r-- | sys/kern/kern_prot.c | 68 |
1 files changed, 45 insertions, 23 deletions
diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c index 3c145851b683..81099aa7d28d 100644 --- a/sys/kern/kern_prot.c +++ b/sys/kern/kern_prot.c @@ -422,7 +422,7 @@ again: * pid must be in same session (EPERM) * pid can't have done an exec (EACCES) * if pgid != pid - * there must exist some pid in same session having pgid (EPERM) + * there must exist some pid in same session having pgid (EPERM) * pid must not be session leader (EPERM) */ #ifndef _SYS_SYSPROTO_H_ @@ -603,8 +603,8 @@ user_setcred(struct thread *td, const u_int flags, if (error != 0) return (error); /* These fields have exactly the same sizes and positions. */ - memcpy(&wcred, &wcred32, &wcred32.setcred32_copy_end - - &wcred32.setcred32_copy_start); + memcpy(&wcred, &wcred32, __rangeof(struct setcred32, + setcred32_copy_start, setcred32_copy_end)); /* Remaining fields are pointers and need PTRIN*(). */ PTRIN_CP(wcred32, wcred, sc_supp_groups); PTRIN_CP(wcred32, wcred, sc_label); @@ -832,22 +832,31 @@ kern_setcred(struct thread *const td, const u_int flags, if (error != 0) goto unlock_finish; +#ifdef RACCT /* - * Set the new credentials, noting that they have changed. + * Hold a reference to 'new_cred', as we need to call some functions on + * it after proc_set_cred_enforce_proc_lim(). */ + crhold(new_cred); +#endif + + /* Set the new credentials. */ cred_set = proc_set_cred_enforce_proc_lim(p, new_cred); if (cred_set) { setsugid(p); - to_free_cred = old_cred; #ifdef RACCT + /* Adjust RACCT counters. */ racct_proc_ucred_changed(p, old_cred, new_cred); #endif -#ifdef RCTL - crhold(new_cred); -#endif + to_free_cred = old_cred; MPASS(error == 0); - } else + } else { +#ifdef RACCT + /* Matches the crhold() just before the containing 'if'. */ + crfree(new_cred); +#endif error = EAGAIN; + } unlock_finish: PROC_UNLOCK(p); @@ -857,10 +866,12 @@ unlock_finish: * finishing operations. */ -#ifdef RCTL +#ifdef RACCT if (cred_set) { +#ifdef RCTL rctl_proc_ucred_changed(p, new_cred); - /* Paired with the crhold() just above. */ +#endif + /* Paired with the crhold() above. */ crfree(new_cred); } #endif @@ -991,16 +1002,19 @@ sys_setuid(struct thread *td, struct setuid_args *uap) change_euid(newcred, uip); setsugid(p); } - /* - * This also transfers the proc count to the new user. - */ - proc_set_cred(p, newcred); + #ifdef RACCT racct_proc_ucred_changed(p, oldcred, newcred); #endif #ifdef RCTL crhold(newcred); #endif + /* + * Takes over 'newcred''s reference, so 'newcred' must not be used + * besides this point except on RCTL where we took an additional + * reference above. + */ + proc_set_cred(p, newcred); PROC_UNLOCK(p); #ifdef RCTL rctl_proc_ucred_changed(p, newcred); @@ -1404,13 +1418,18 @@ sys_setreuid(struct thread *td, struct setreuid_args *uap) change_svuid(newcred, newcred->cr_uid); setsugid(p); } - proc_set_cred(p, newcred); #ifdef RACCT racct_proc_ucred_changed(p, oldcred, newcred); #endif #ifdef RCTL crhold(newcred); #endif + /* + * Takes over 'newcred''s reference, so 'newcred' must not be used + * besides this point except on RCTL where we took an additional + * reference above. + */ + proc_set_cred(p, newcred); PROC_UNLOCK(p); #ifdef RCTL rctl_proc_ucred_changed(p, newcred); @@ -1552,13 +1571,18 @@ sys_setresuid(struct thread *td, struct setresuid_args *uap) change_svuid(newcred, suid); setsugid(p); } - proc_set_cred(p, newcred); #ifdef RACCT racct_proc_ucred_changed(p, oldcred, newcred); #endif #ifdef RCTL crhold(newcred); #endif + /* + * Takes over 'newcred''s reference, so 'newcred' must not be used + * besides this point except on RCTL where we took an additional + * reference above. + */ + proc_set_cred(p, newcred); PROC_UNLOCK(p); #ifdef RCTL rctl_proc_ucred_changed(p, newcred); @@ -2783,7 +2807,7 @@ cru2xt(struct thread *td, struct xucred *xcr) * 'enforce_proc_lim' being true and if no new process can be accounted to the * new real UID because of the current limit (see the inner comment for more * details) and the caller does not have privilege (PRIV_PROC_LIMIT) to override - * that. + * that. In this case, the reference to 'newcred' is not taken over. */ static bool _proc_set_cred(struct proc *p, struct ucred *newcred, bool enforce_proc_lim) @@ -2792,10 +2816,6 @@ _proc_set_cred(struct proc *p, struct ucred *newcred, bool enforce_proc_lim) MPASS(oldcred != NULL); PROC_LOCK_ASSERT(p, MA_OWNED); - KASSERT(newcred->cr_users == 0, ("%s: users %d not 0 on cred %p", - __func__, newcred->cr_users, newcred)); - KASSERT(newcred->cr_ref == 1, ("%s: ref %ld not 1 on cred %p", - __func__, newcred->cr_ref, newcred)); if (newcred->cr_ruidinfo != oldcred->cr_ruidinfo) { /* @@ -2821,8 +2841,10 @@ _proc_set_cred(struct proc *p, struct ucred *newcred, bool enforce_proc_lim) __func__, oldcred->cr_users, oldcred)); oldcred->cr_users--; mtx_unlock(&oldcred->cr_mtx); + mtx_lock(&newcred->cr_mtx); + newcred->cr_users++; + mtx_unlock(&newcred->cr_mtx); p->p_ucred = newcred; - newcred->cr_users = 1; PROC_UPDATE_COW(p); if (newcred->cr_ruidinfo != oldcred->cr_ruidinfo) (void)chgproccnt(oldcred->cr_ruidinfo, -1, 0); |