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authorYunhong Jiang <yunhong.jiang@linux.intel.com>2017-03-08 23:13:28 -0800
committerYunhong Jiang <yunhong.jiang@linux.intel.com>2017-03-08 23:36:15 -0800
commit52f993b8e89487ec9ee15a7fb4979e0f09a45b27 (patch)
treed65304486afe0bea4a311c783c0d72791c8c0aa2 /kernel/fs/overlayfs/dir.c
parentc189ccac5702322ed843fe17057035b7222a59b6 (diff)
Upgrade to 4.4.50-rt62
The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it to 4.4.50-rt62. The command to achieve it is: a) Clone a git repo from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git b) Get the diff between this two changesets: git diff 640eca2901f3435e616157b11379d3223a44b391 705619beeea1b0b48219a683fd1a901a86fdaf5e where the two commits are: [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 640eca2901f3435e616157b11379d3223a44b391 640eca2901f3 v4.4.6-rt14 localversion-rt [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 705619beeea1b0b48219a683fd1a901a86fdaf5e 705619beeea1 Linux 4.4.50-rt62 localversion-rt c) One patch has been backported thus revert the patch before applying. filterdiff -p1 -x scripts/package/Makefile ~/tmp/v4.4.6-rt14-4.4.50-rt62.diff |patch -p1 --dry-run Upstream status: backport Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01 Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>
Diffstat (limited to 'kernel/fs/overlayfs/dir.c')
-rw-r--r--kernel/fs/overlayfs/dir.c118
1 files changed, 66 insertions, 52 deletions
diff --git a/kernel/fs/overlayfs/dir.c b/kernel/fs/overlayfs/dir.c
index a2b1d7ce3..327177df0 100644
--- a/kernel/fs/overlayfs/dir.c
+++ b/kernel/fs/overlayfs/dir.c
@@ -12,6 +12,7 @@
#include <linux/xattr.h>
#include <linux/security.h>
#include <linux/cred.h>
+#include <linux/atomic.h>
#include "overlayfs.h"
void ovl_cleanup(struct inode *wdir, struct dentry *wdentry)
@@ -35,8 +36,10 @@ struct dentry *ovl_lookup_temp(struct dentry *workdir, struct dentry *dentry)
{
struct dentry *temp;
char name[20];
+ static atomic_t temp_id = ATOMIC_INIT(0);
- snprintf(name, sizeof(name), "#%lx", (unsigned long) dentry);
+ /* counter is allowed to wrap, since temp dentries are ephemeral */
+ snprintf(name, sizeof(name), "#%x", atomic_inc_return(&temp_id));
temp = lookup_one_len(name, workdir, strlen(name));
if (!IS_ERR(temp) && temp->d_inode) {
@@ -511,6 +514,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
struct dentry *upper;
struct dentry *opaquedir = NULL;
int err;
+ int flags = 0;
if (WARN_ON(!workdir))
return -EROFS;
@@ -540,46 +544,39 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
if (err)
goto out_dput;
- whiteout = ovl_whiteout(workdir, dentry);
- err = PTR_ERR(whiteout);
- if (IS_ERR(whiteout))
+ upper = lookup_one_len(dentry->d_name.name, upperdir,
+ dentry->d_name.len);
+ err = PTR_ERR(upper);
+ if (IS_ERR(upper))
goto out_unlock;
- upper = ovl_dentry_upper(dentry);
- if (!upper) {
- upper = lookup_one_len(dentry->d_name.name, upperdir,
- dentry->d_name.len);
- err = PTR_ERR(upper);
- if (IS_ERR(upper))
- goto kill_whiteout;
-
- err = ovl_do_rename(wdir, whiteout, udir, upper, 0);
- dput(upper);
- if (err)
- goto kill_whiteout;
- } else {
- int flags = 0;
+ err = -ESTALE;
+ if ((opaquedir && upper != opaquedir) ||
+ (!opaquedir && ovl_dentry_upper(dentry) &&
+ upper != ovl_dentry_upper(dentry))) {
+ goto out_dput_upper;
+ }
- if (opaquedir)
- upper = opaquedir;
- err = -ESTALE;
- if (upper->d_parent != upperdir)
- goto kill_whiteout;
+ whiteout = ovl_whiteout(workdir, dentry);
+ err = PTR_ERR(whiteout);
+ if (IS_ERR(whiteout))
+ goto out_dput_upper;
- if (is_dir)
- flags |= RENAME_EXCHANGE;
+ if (d_is_dir(upper))
+ flags = RENAME_EXCHANGE;
- err = ovl_do_rename(wdir, whiteout, udir, upper, flags);
- if (err)
- goto kill_whiteout;
+ err = ovl_do_rename(wdir, whiteout, udir, upper, flags);
+ if (err)
+ goto kill_whiteout;
+ if (flags)
+ ovl_cleanup(wdir, upper);
- if (is_dir)
- ovl_cleanup(wdir, upper);
- }
ovl_dentry_version_inc(dentry->d_parent);
out_d_drop:
d_drop(dentry);
dput(whiteout);
+out_dput_upper:
+ dput(upper);
out_unlock:
unlock_rename(workdir, upperdir);
out_dput:
@@ -596,21 +593,25 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir)
{
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
struct inode *dir = upperdir->d_inode;
- struct dentry *upper = ovl_dentry_upper(dentry);
+ struct dentry *upper;
int err;
mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
+ upper = lookup_one_len(dentry->d_name.name, upperdir,
+ dentry->d_name.len);
+ err = PTR_ERR(upper);
+ if (IS_ERR(upper))
+ goto out_unlock;
+
err = -ESTALE;
- if (upper->d_parent == upperdir) {
- /* Don't let d_delete() think it can reset d_inode */
- dget(upper);
+ if (upper == ovl_dentry_upper(dentry)) {
if (is_dir)
err = vfs_rmdir(dir, upper);
else
err = vfs_unlink(dir, upper, NULL);
- dput(upper);
ovl_dentry_version_inc(dentry->d_parent);
}
+ dput(upper);
/*
* Keeping this dentry hashed would mean having to release
@@ -620,6 +621,7 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir)
*/
if (!err)
d_drop(dentry);
+out_unlock:
mutex_unlock(&dir->i_mutex);
return err;
@@ -840,29 +842,39 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old,
trap = lock_rename(new_upperdir, old_upperdir);
- olddentry = ovl_dentry_upper(old);
- newdentry = ovl_dentry_upper(new);
- if (newdentry) {
+
+ olddentry = lookup_one_len(old->d_name.name, old_upperdir,
+ old->d_name.len);
+ err = PTR_ERR(olddentry);
+ if (IS_ERR(olddentry))
+ goto out_unlock;
+
+ err = -ESTALE;
+ if (olddentry != ovl_dentry_upper(old))
+ goto out_dput_old;
+
+ newdentry = lookup_one_len(new->d_name.name, new_upperdir,
+ new->d_name.len);
+ err = PTR_ERR(newdentry);
+ if (IS_ERR(newdentry))
+ goto out_dput_old;
+
+ err = -ESTALE;
+ if (ovl_dentry_upper(new)) {
if (opaquedir) {
- newdentry = opaquedir;
- opaquedir = NULL;
+ if (newdentry != opaquedir)
+ goto out_dput;
} else {
- dget(newdentry);
+ if (newdentry != ovl_dentry_upper(new))
+ goto out_dput;
}
} else {
new_create = true;
- newdentry = lookup_one_len(new->d_name.name, new_upperdir,
- new->d_name.len);
- err = PTR_ERR(newdentry);
- if (IS_ERR(newdentry))
- goto out_unlock;
+ if (!d_is_negative(newdentry) &&
+ (!new_opaque || !ovl_is_whiteout(newdentry)))
+ goto out_dput;
}
- err = -ESTALE;
- if (olddentry->d_parent != old_upperdir)
- goto out_dput;
- if (newdentry->d_parent != new_upperdir)
- goto out_dput;
if (olddentry == trap)
goto out_dput;
if (newdentry == trap)
@@ -925,6 +937,8 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old,
out_dput:
dput(newdentry);
+out_dput_old:
+ dput(olddentry);
out_unlock:
unlock_rename(new_upperdir, old_upperdir);
out_revert_creds: