The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=836749817036b90b60af0584fa21f2d9dbd60ff7
commit 836749817036b90b60af0584fa21f2d9dbd60ff7 Author: Konstantin Belousov <[email protected]> AuthorDate: 2026-06-16 04:34:16 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2026-06-21 11:46:53 +0000 kern_resource.c: disallow execve around sysctl kern.proc.rlimitusage Reviewed by: markj Tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: htts://reviews.freebsd.org/D57497 --- sys/kern/kern_resource.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/sys/kern/kern_resource.c b/sys/kern/kern_resource.c index 95c4e7d5eead..044e95fa64a0 100644 --- a/sys/kern/kern_resource.c +++ b/sys/kern/kern_resource.c @@ -46,6 +46,7 @@ #include <sys/mutex.h> #include <sys/priv.h> #include <sys/proc.h> +#include <sys/ptrace.h> #include <sys/refcount.h> #include <sys/racct.h> #include <sys/resourcevar.h> @@ -823,11 +824,11 @@ sys_getrlimit(struct thread *td, struct getrlimit_args *uap) } static int -getrlimitusage_one(struct proc *p, u_int which, int flags, rlim_t *res) +getrlimitusage_one(struct proc *p, struct vmspace *vm, u_int which, int flags, + rlim_t *res) { struct thread *td; struct uidinfo *ui; - struct vmspace *vm; uid_t uid; int error; @@ -838,7 +839,6 @@ getrlimitusage_one(struct proc *p, u_int which, int flags, rlim_t *res) PROC_UNLOCK(p); ui = uifind(uid); - vm = vmspace_acquire_ref(p); switch (which) { case RLIMIT_CPU: @@ -919,7 +919,6 @@ getrlimitusage_one(struct proc *p, u_int which, int flags, rlim_t *res) break; } - vmspace_free(vm); uifree(ui); return (error); } @@ -927,12 +926,15 @@ getrlimitusage_one(struct proc *p, u_int which, int flags, rlim_t *res) int sys_getrlimitusage(struct thread *td, struct getrlimitusage_args *uap) { + struct proc *p; rlim_t res; int error; if ((uap->flags & ~(GETRLIMITUSAGE_EUID)) != 0) return (EINVAL); - error = getrlimitusage_one(curproc, uap->which, uap->flags, &res); + p = curproc; + error = getrlimitusage_one(p, p->p_vmspace, uap->which, uap->flags, + &res); if (error == 0) error = copyout(&res, uap->res, sizeof(res)); return (error); @@ -1797,6 +1799,8 @@ sysctl_kern_proc_rlimit_usage(SYSCTL_HANDLER_ARGS) { rlim_t resval[RLIM_NLIMITS]; struct proc *p; + struct thread *td; + struct vmspace *vm; size_t len; int error, *name, i; @@ -1806,15 +1810,20 @@ sysctl_kern_proc_rlimit_usage(SYSCTL_HANDLER_ARGS) if (req->newptr != NULL) return (EINVAL); - error = pget((pid_t)name[0], PGET_WANTREAD, &p); + td = curthread; + error = pget((pid_t)name[0], PGET_HOLD | PGET_NOTWEXIT, &p); if (error != 0) return (error); + error = proc_vmspace_ref(td, p, PRVM_BLOCK_EXEC | + PRVM_CHECK_VISIBILITY, &vm); + if (error != 0) + goto out; if ((u_int)arg2 == 1) { len = sizeof(resval); memset(resval, 0, sizeof(resval)); for (i = 0; i < RLIM_NLIMITS; i++) { - error = getrlimitusage_one(p, (unsigned)i, 0, + error = getrlimitusage_one(p, vm, (unsigned)i, 0, &resval[i]); if (error == ENXIO) { resval[i] = -1; @@ -1825,7 +1834,7 @@ sysctl_kern_proc_rlimit_usage(SYSCTL_HANDLER_ARGS) } } else { len = sizeof(resval[0]); - error = getrlimitusage_one(p, (unsigned)name[1], 0, + error = getrlimitusage_one(p, vm, (unsigned)name[1], 0, &resval[0]); if (error == ENXIO) { resval[0] = -1; @@ -1834,6 +1843,8 @@ sysctl_kern_proc_rlimit_usage(SYSCTL_HANDLER_ARGS) } if (error == 0) error = SYSCTL_OUT(req, resval, len); + proc_vmspace_unref(td, p, PRVM_BLOCK_EXEC | PRVM_CHECK_VISIBILITY, vm); +out: PRELE(p); return (error); }
