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authorDavid S. Miller <davem@davemloft.net>2020-07-25 17:49:04 -0700
committerDavid S. Miller <davem@davemloft.net>2020-07-25 17:49:04 -0700
commita57066b1a01977a646145f4ce8dfb4538b08368a (patch)
tree57c2b4fa2fc48e687a1820b9bf4ef4f4363be0f9 /fs/overlayfs/super.c
parentdfecd3e00cd32b2a6d1cfdb30b513dd42575ada3 (diff)
parent04300d66f0a06d572d9f2ad6768c38cabde22179 (diff)
downloadlinux-a57066b1a01977a646145f4ce8dfb4538b08368a.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'fs/overlayfs/super.c')
-rw-r--r--fs/overlayfs/super.c73
1 files changed, 49 insertions, 24 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 91476bc422f9..4b38141c2985 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -580,12 +580,19 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config)
}
}
- /* Workdir is useless in non-upper mount */
- if (!config->upperdir && config->workdir) {
- pr_info("option \"workdir=%s\" is useless in a non-upper mount, ignore\n",
- config->workdir);
- kfree(config->workdir);
- config->workdir = NULL;
+ /* Workdir/index are useless in non-upper mount */
+ if (!config->upperdir) {
+ if (config->workdir) {
+ pr_info("option \"workdir=%s\" is useless in a non-upper mount, ignore\n",
+ config->workdir);
+ kfree(config->workdir);
+ config->workdir = NULL;
+ }
+ if (config->index && index_opt) {
+ pr_info("option \"index=on\" is useless in a non-upper mount, ignore\n");
+ index_opt = false;
+ }
+ config->index = false;
}
err = ovl_parse_redirect_mode(config, config->redirect_mode);
@@ -622,11 +629,13 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config)
/* Resolve nfs_export -> index dependency */
if (config->nfs_export && !config->index) {
- if (nfs_export_opt && index_opt) {
+ if (!config->upperdir && config->redirect_follow) {
+ pr_info("NFS export requires \"redirect_dir=nofollow\" on non-upper mount, falling back to nfs_export=off.\n");
+ config->nfs_export = false;
+ } else if (nfs_export_opt && index_opt) {
pr_err("conflicting options: nfs_export=on,index=off\n");
return -EINVAL;
- }
- if (index_opt) {
+ } else if (index_opt) {
/*
* There was an explicit index=off that resulted
* in this conflict.
@@ -1352,8 +1361,15 @@ static int ovl_get_indexdir(struct super_block *sb, struct ovl_fs *ofs,
goto out;
}
+ /* index dir will act also as workdir */
+ iput(ofs->workdir_trap);
+ ofs->workdir_trap = NULL;
+ dput(ofs->workdir);
+ ofs->workdir = NULL;
ofs->indexdir = ovl_workdir_create(ofs, OVL_INDEXDIR_NAME, true);
if (ofs->indexdir) {
+ ofs->workdir = dget(ofs->indexdir);
+
err = ovl_setup_trap(sb, ofs->indexdir, &ofs->indexdir_trap,
"indexdir");
if (err)
@@ -1396,6 +1412,18 @@ static bool ovl_lower_uuid_ok(struct ovl_fs *ofs, const uuid_t *uuid)
if (!ofs->config.nfs_export && !ovl_upper_mnt(ofs))
return true;
+ /*
+ * We allow using single lower with null uuid for index and nfs_export
+ * for example to support those features with single lower squashfs.
+ * To avoid regressions in setups of overlay with re-formatted lower
+ * squashfs, do not allow decoding origin with lower null uuid unless
+ * user opted-in to one of the new features that require following the
+ * lower inode of non-dir upper.
+ */
+ if (!ofs->config.index && !ofs->config.metacopy && !ofs->config.xino &&
+ uuid_is_null(uuid))
+ return false;
+
for (i = 0; i < ofs->numfs; i++) {
/*
* We use uuid to associate an overlay lower file handle with a
@@ -1493,14 +1521,23 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs,
if (err < 0)
goto out;
+ /*
+ * Check if lower root conflicts with this overlay layers before
+ * checking if it is in-use as upperdir/workdir of "another"
+ * mount, because we do not bother to check in ovl_is_inuse() if
+ * the upperdir/workdir is in fact in-use by our
+ * upperdir/workdir.
+ */
err = ovl_setup_trap(sb, stack[i].dentry, &trap, "lowerdir");
if (err)
goto out;
if (ovl_is_inuse(stack[i].dentry)) {
err = ovl_report_in_use(ofs, "lowerdir");
- if (err)
+ if (err) {
+ iput(trap);
goto out;
+ }
}
mnt = clone_private_mount(&stack[i]);
@@ -1575,10 +1612,6 @@ static struct ovl_entry *ovl_get_lowerstack(struct super_block *sb,
if (!ofs->config.upperdir && numlower == 1) {
pr_err("at least 2 lowerdir are needed while upperdir nonexistent\n");
return ERR_PTR(-EINVAL);
- } else if (!ofs->config.upperdir && ofs->config.nfs_export &&
- ofs->config.redirect_follow) {
- pr_warn("NFS export requires \"redirect_dir=nofollow\" on non-upper mount, falling back to nfs_export=off.\n");
- ofs->config.nfs_export = false;
}
stack = kcalloc(numlower, sizeof(struct path), GFP_KERNEL);
@@ -1842,21 +1875,13 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
if (!ovl_upper_mnt(ofs))
sb->s_flags |= SB_RDONLY;
- if (!(ovl_force_readonly(ofs)) && ofs->config.index) {
- /* index dir will act also as workdir */
- dput(ofs->workdir);
- ofs->workdir = NULL;
- iput(ofs->workdir_trap);
- ofs->workdir_trap = NULL;
-
+ if (!ovl_force_readonly(ofs) && ofs->config.index) {
err = ovl_get_indexdir(sb, ofs, oe, &upperpath);
if (err)
goto out_free_oe;
/* Force r/o mount with no index dir */
- if (ofs->indexdir)
- ofs->workdir = dget(ofs->indexdir);
- else
+ if (!ofs->indexdir)
sb->s_flags |= SB_RDONLY;
}