Skip site navigation (1)Skip section navigation (2) 
Date:      Fri, 17 Jun 2022 19:39:24 GMT
From:      Dmitry Chagin <dchagin@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Subject:   git: c78e5c4c6ac3 - stable/13 - linux(4): Copyout pselect timeout.
Message-ID:  <202206171939.25HJdOQU015960@gitrepo.freebsd.org>
next in thread | raw e-mail | index | archive | help 
The branch stable/13 has been updated by dchagin:

URL: https://cgit.FreeBSD.org/src/commit/?id=c78e5c4c6ac358a05195b249b65a1a42c4291c03

commit c78e5c4c6ac358a05195b249b65a1a42c4291c03
Author:     Dmitry Chagin <dchagin@FreeBSD.org>
AuthorDate: 2022-04-26 16:35:56 +0000
Commit:     Dmitry Chagin <dchagin@FreeBSD.org>
CommitDate: 2022-06-17 19:34:04 +0000

    linux(4): Copyout pselect timeout.
    
    According to pselect6 manual, on error timeout becomes undefined, by fact
    Linux modifies the timeout and ignore EFAULT error if so.
    
    MFC after:      2 weeks
    
    (cherry picked from commit 5171ed79f6d1fc3948a7ebfb32b02d698224c29b)
---
 sys/compat/linux/linux_misc.c | 46 ++++++++++++++++++-------------------------
 1 file changed, 19 insertions(+), 27 deletions(-)

diff --git a/sys/compat/linux/linux_misc.c b/sys/compat/linux/linux_misc.c
index 096bbcbf0008..ff8c1b26d1d8 100644
--- a/sys/compat/linux/linux_misc.c
+++ b/sys/compat/linux/linux_misc.c
@@ -2386,7 +2386,7 @@ linux_pselect6(struct thread *td, struct linux_pselect6_args *args)
 {
 	struct l_timespec lts;
 	struct timespec ts, *tsp;
-	int error;
+	int error, error2;
 
 	if (args->tsp != NULL) {
 		error = copyin(args->tsp, &lts, sizeof(lts));
@@ -2401,13 +2401,11 @@ linux_pselect6(struct thread *td, struct linux_pselect6_args *args)
 
 	error = linux_common_pselect6(td, args->nfds, args->readfds,
 	    args->writefds, args->exceptfds, tsp, args->sig);
-	if (error != 0)
-		return (error);
 
 	if (args->tsp != NULL) {
-		error = native_to_linux_timespec(&lts, tsp);
-		if (error == 0)
-			error = copyout(&lts, args->tsp, sizeof(lts));
+		error2 = native_to_linux_timespec(&lts, tsp);
+		if (error2 == 0)
+			copyout(&lts, args->tsp, sizeof(lts));
 	}
 	return (error);
 }
@@ -2459,21 +2457,17 @@ linux_common_pselect6(struct thread *td, l_int nfds, l_fd_set *readfds,
 	error = kern_pselect(td, nfds, readfds, writefds,
 	    exceptfds, tvp, ssp, LINUX_NFDBITS);
 
-	if (error == 0 && tsp != NULL) {
-		if (td->td_retval[0] != 0) {
-			/*
-			 * Compute how much time was left of the timeout,
-			 * by subtracting the current time and the time
-			 * before we started the call, and subtracting
-			 * that result from the user-supplied value.
-			 */
-
-			microtime(&tv1);
-			timevalsub(&tv1, &tv0);
-			timevalsub(&utv, &tv1);
-			if (utv.tv_sec < 0)
-				timevalclear(&utv);
-		} else
+	if (tsp != NULL) {
+		/*
+		 * Compute how much time was left of the timeout,
+		 * by subtracting the current time and the time
+		 * before we started the call, and subtracting
+		 * that result from the user-supplied value.
+		 */
+		microtime(&tv1);
+		timevalsub(&tv1, &tv0);
+		timevalsub(&utv, &tv1);
+		if (utv.tv_sec < 0)
 			timevalclear(&utv);
 		TIMEVAL_TO_TIMESPEC(&utv, tsp);
 	}
@@ -2487,7 +2481,7 @@ linux_pselect6_time64(struct thread *td,
 {
 	struct l_timespec64 lts;
 	struct timespec ts, *tsp;
-	int error;
+	int error, error2;
 
 	if (args->tsp != NULL) {
 		error = copyin(args->tsp, &lts, sizeof(lts));
@@ -2502,13 +2496,11 @@ linux_pselect6_time64(struct thread *td,
 
 	error = linux_common_pselect6(td, args->nfds, args->readfds,
 	    args->writefds, args->exceptfds, tsp, args->sig);
-	if (error != 0)
-		return (error);
 
 	if (args->tsp != NULL) {
-		error = native_to_linux_timespec64(&lts, tsp);
-		if (error == 0)
-			error = copyout(&lts, args->tsp, sizeof(lts));
+		error2 = native_to_linux_timespec64(&lts, tsp);
+		if (error2 == 0)
+			copyout(&lts, args->tsp, sizeof(lts));
 	}
 	return (error);
 }

Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202206171939.25HJdOQU015960>