git: a9c439ba104d - main - msdosfs: truncate write if it would exceed the fs max file size or RLIMIT_FSIZE

From: Konstantin Belousov <kib_at_FreeBSD.org>
Date: Sat, 24 Sep 2022 16:42:39 UTC
The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=a9c439ba104d83a2666d114dae9f26b2efb22d17

commit a9c439ba104d83a2666d114dae9f26b2efb22d17
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2022-09-18 11:51:33 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2022-09-24 16:42:01 +0000

    msdosfs: truncate write if it would exceed the fs max file size or RLIMIT_FSIZE
    
    PR:     164793
    Reviewed by:    asomers, jah, markj
    Tested by:      pho
    Sponsored by:   The FreeBSD Foundation
    MFC after:      2 weeks
    Differential revision:  https://reviews.freebsd.org/D36625
---
 sys/fs/msdosfs/msdosfs_vnops.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/sys/fs/msdosfs/msdosfs_vnops.c b/sys/fs/msdosfs/msdosfs_vnops.c
index 24d63bd343a9..8fb58a58b138 100644
--- a/sys/fs/msdosfs/msdosfs_vnops.c
+++ b/sys/fs/msdosfs/msdosfs_vnops.c
@@ -614,7 +614,7 @@ msdosfs_write(struct vop_write_args *ap)
 {
 	int n;
 	int croffset;
-	ssize_t resid;
+	ssize_t resid, r;
 	u_long osize;
 	int error = 0;
 	u_long count;
@@ -659,16 +659,15 @@ msdosfs_write(struct vop_write_args *ap)
 	/*
 	 * The caller is supposed to ensure that
 	 * uio->uio_offset >= 0 and uio->uio_resid >= 0.
-	 */
-	if ((uoff_t)uio->uio_offset + uio->uio_resid > MSDOSFS_FILESIZE_MAX)
-		return (EFBIG);
-
-	/*
+	 *
 	 * If they've exceeded their filesize limit, tell them about it.
 	 */
-	error = vn_rlimit_fsize(vp, uio, uio->uio_td);
-	if (error != 0)
+	error = vn_rlimit_fsizex(vp, uio, MSDOSFS_FILESIZE_MAX, &r,
+	    uio->uio_td);
+	if (error != 0) {
+		vn_rlimit_fsizex_res(uio, r);
 		return (error);
+	}
 
 	/*
 	 * If the offset we are starting the write at is beyond the end of
@@ -678,8 +677,10 @@ msdosfs_write(struct vop_write_args *ap)
 	 */
 	if (uio->uio_offset > dep->de_FileSize) {
 		error = deextend(dep, uio->uio_offset, cred);
-		if (error)
+		if (error != 0) {
+			vn_rlimit_fsizex_res(uio, r);
 			return (error);
+		}
 	}
 
 	/*
@@ -822,6 +823,7 @@ errexit:
 		}
 	} else if (ioflag & IO_SYNC)
 		error = deupdat(dep, 1);
+	vn_rlimit_fsizex_res(uio, r);
 	return (error);
 }