git: 9fefa628025c - stable/15 - fget_remote(): return fcaps and fde_flags if requested

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=9fefa628025cbd0f44bab388607b61adf14167d8

commit 9fefa628025cbd0f44bab388607b61adf14167d8
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-05-23 07:03:17 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-08-16 02:41:25 +0000

    fget_remote(): return fcaps and fde_flags if requested
    
    (cherry picked from commit 77b6adbe5e351d1907e14d21c49291ff40ba879a)
---
 sys/kern/kern_descrip.c | 19 ++++++++++++++++---
 sys/kern/kern_event.c   |  2 +-
 sys/kern/sys_generic.c  |  4 ++--
 sys/sys/file.h          |  3 ++-
 4 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index ec9fbdae2fa7..b10b7f4f90bb 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -3128,13 +3128,20 @@ fget_cap(struct thread *td, int fd, const cap_rights_t *needrightsp,
 #endif
 
 int
-fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp)
+fget_remote(struct thread *td, struct proc *p, int fd, struct filecaps *fcaps,
+    uint8_t *fd_flags, struct file **fpp)
 {
 	struct filedesc *fdp;
 	struct file *fp;
 	int error;
 
-	if (p == td->td_proc)	/* curproc */
+	/*
+	 * Both fcaps and fd_flags must be either requested together,
+	 * or not at all.
+	 */
+	MPASS((!(fcaps == NULL) ^ (fd_flags == NULL)));
+
+	if (p == td->td_proc && fcaps == NULL)	/* curproc */
 		return (fget_unlocked(td, fd, &cap_no_rights, fpp));
 
 	PROC_LOCK(p);
@@ -3147,6 +3154,12 @@ fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp)
 		fp = fget_noref(fdp, fd);
 		if (fp != NULL && fhold(fp)) {
 			*fpp = fp;
+			if (fd_flags != NULL) {
+				*fd_flags = fde_to_fd_flags(fdp->fd_ofiles[fd].
+				    fde_flags);
+			}
+			if (fcaps != NULL)
+				*fcaps = fdp->fd_ofiles[fd].fde_caps;
 			error = 0;
 		} else {
 			error = EBADF;
@@ -3187,7 +3200,7 @@ fget_remote_foreach(struct thread *td, struct proc *p,
 	}
 
 	for (fd = 0; fd <= highfd; fd++) {
-		error1 = fget_remote(td, p, fd, &fp);
+		error1 = fget_remote(td, p, fd, NULL, NULL, &fp);
 		if (error1 != 0)
 			continue;
 		error = fn(p, fd, fp, arg);
diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c
index 62c449e59f68..456eddfaea9f 100644
--- a/sys/kern/kern_event.c
+++ b/sys/kern/kern_event.c
@@ -3391,7 +3391,7 @@ sysctl_kern_proc_kqueue_one(struct thread *td, struct sbuf *s, struct proc *p,
 	struct kqueue *kq;
 	int error;
 
-	error = fget_remote(td, p, kq_fd, &fp);
+	error = fget_remote(td, p, kq_fd, NULL, NULL, &fp);
 	if (error == 0) {
 		if (fp->f_type != DTYPE_KQUEUE) {
 			error = EINVAL;
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index b829a70f26aa..c6aa06e62be6 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -2208,9 +2208,9 @@ kern_kcmp(struct thread *td, pid_t pid1, pid_t pid2, int type,
 	switch (type) {
 	case KCMP_FILE:
 	case KCMP_FILEOBJ:
-		error = fget_remote(td, p1, idx1, &fp1);
+		error = fget_remote(td, p1, idx1, NULL, NULL, &fp1);
 		if (error == 0) {
-			error = fget_remote(td, p2, idx2, &fp2);
+			error = fget_remote(td, p2, idx2, NULL, NULL, &fp2);
 			if (error == 0) {
 				if (type == KCMP_FILEOBJ)
 					res = fo_cmp(fp1, fp2, td);
diff --git a/sys/sys/file.h b/sys/sys/file.h
index bc529df82048..055e6b38483d 100644
--- a/sys/sys/file.h
+++ b/sys/sys/file.h
@@ -283,7 +283,8 @@ int fget_write(struct thread *td, int fd, const cap_rights_t *rightsp,
 int fget_fcntl(struct thread *td, int fd, const cap_rights_t *rightsp,
     int needfcntl, struct file **fpp);
 int _fdrop(struct file *fp, struct thread *td);
-int fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp);
+int fget_remote(struct thread *td, struct proc *p, int fd,
+    struct filecaps *fcaps, uint8_t *fd_flags, struct file **fpp);
 int fget_remote_foreach(struct thread *td, struct proc *p,
     int (*fn)(struct proc *, int, struct file *, void *), void *arg);