Module Name: src
Committed By: chs
Date: Wed May 13 05:52:54 UTC 2020
Modified Files:
src/external/cddl/osnet/dist/uts/common/fs/zfs: zfs_vnops.c
Log Message:
fix the handling in putpage of the page containing EOF.
To generate a diff of this commit:
cvs rdiff -u -r1.65 -r1.66 \
src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c
diff -u src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c:1.65 src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c:1.66
--- src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c:1.65 Thu May 7 09:12:03 2020
+++ src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c Wed May 13 05:52:54 2020
@@ -6066,9 +6066,29 @@ zfs_putapage(vnode_t *vp, page_t **pp, i
goto out_unbusy;
}
+ /*
+ * Calculate the length and assert that no whole pages are past EOF.
+ * This check is equivalent to "off + len <= round_page(zp->z_size)",
+ * with gyrations to avoid signed integer overflow.
+ */
+
off = pp[0]->offset;
len = count * PAGESIZE;
- KASSERT(off + len <= round_page(zp->z_size));
+ KASSERT(off <= zp->z_size);
+ KASSERT(len <= round_page(zp->z_size));
+ KASSERT(off <= round_page(zp->z_size) - len);
+
+ /*
+ * If EOF is within the last page, reduce len to avoid writing past
+ * the file size in the ZFS buffer. Assert that
+ * "off + len <= zp->z_size", again avoiding signed integer overflow.
+ */
+
+ if (len > zp->z_size - off) {
+ len = zp->z_size - off;
+ }
+ KASSERT(len <= zp->z_size);
+ KASSERT(off <= zp->z_size - len);
if (zfs_owner_overquota(zfsvfs, zp, B_FALSE) ||
zfs_owner_overquota(zfsvfs, zp, B_TRUE)) {
