summaryrefslogtreecommitdiff
path: root/fs/overlayfs
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-09 10:51:12 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-09 10:51:12 -0800
commit1bdd629e5aa0e335504304be4208935948692549 (patch)
treecd64cb149797dd9b83209046c6190ed4950cf6d9 /fs/overlayfs
parentcdd39b0539c4271d4242bc780fb1f04e130c4377 (diff)
parent5b0a414d06c3ed2097e32ef7944a4abb644b89bd (diff)
Merge tag 'ovl-update-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs updates from Miklos Szeredi: - Fix a regression introduced in the last cycle - Fix a use-after-free in the AIO path - Fix a bogus warning reported by syzbot * tag 'ovl-update-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: fix filattr copy-up failure ovl: fix warning in ovl_create_real() ovl: fix use after free in struct ovl_aio_req
Diffstat (limited to 'fs/overlayfs')
-rw-r--r--fs/overlayfs/copy_up.c23
-rw-r--r--fs/overlayfs/dir.c3
-rw-r--r--fs/overlayfs/file.c16
-rw-r--r--fs/overlayfs/inode.c5
-rw-r--r--fs/overlayfs/overlayfs.h1
-rw-r--r--fs/overlayfs/super.c12
6 files changed, 46 insertions, 14 deletions
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 4e7d5bfa2949..b193d08a3dc3 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -140,12 +140,14 @@ static int ovl_copy_fileattr(struct inode *inode, struct path *old,
int err;
err = ovl_real_fileattr_get(old, &oldfa);
- if (err)
- return err;
-
- err = ovl_real_fileattr_get(new, &newfa);
- if (err)
+ if (err) {
+ /* Ntfs-3g returns -EINVAL for "no fileattr support" */
+ if (err == -ENOTTY || err == -EINVAL)
+ return 0;
+ pr_warn("failed to retrieve lower fileattr (%pd2, err=%i)\n",
+ old, err);
return err;
+ }
/*
* We cannot set immutable and append-only flags on upper inode,
@@ -159,6 +161,17 @@ static int ovl_copy_fileattr(struct inode *inode, struct path *old,
return err;
}
+ /* Don't bother copying flags if none are set */
+ if (!(oldfa.flags & OVL_COPY_FS_FLAGS_MASK))
+ return 0;
+
+ err = ovl_real_fileattr_get(new, &newfa);
+ if (err) {
+ pr_warn("failed to retrieve upper fileattr (%pd2, err=%i)\n",
+ new, err);
+ return err;
+ }
+
BUILD_BUG_ON(OVL_COPY_FS_FLAGS_MASK & ~FS_COMMON_FL);
newfa.flags &= ~OVL_COPY_FS_FLAGS_MASK;
newfa.flags |= (oldfa.flags & OVL_COPY_FS_FLAGS_MASK);
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 93c7c267de93..f18490813170 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -137,8 +137,7 @@ kill_whiteout:
goto out;
}
-static int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry,
- umode_t mode)
+int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry, umode_t mode)
{
int err;
struct dentry *d, *dentry = *newdentry;
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index ac461a499882..fa125feed0ff 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -17,6 +17,7 @@
struct ovl_aio_req {
struct kiocb iocb;
+ refcount_t ref;
struct kiocb *orig_iocb;
struct fd fd;
};
@@ -252,6 +253,14 @@ static rwf_t ovl_iocb_to_rwf(int ifl)
return flags;
}
+static inline void ovl_aio_put(struct ovl_aio_req *aio_req)
+{
+ if (refcount_dec_and_test(&aio_req->ref)) {
+ fdput(aio_req->fd);
+ kmem_cache_free(ovl_aio_request_cachep, aio_req);
+ }
+}
+
static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
{
struct kiocb *iocb = &aio_req->iocb;
@@ -268,8 +277,7 @@ static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
}
orig_iocb->ki_pos = iocb->ki_pos;
- fdput(aio_req->fd);
- kmem_cache_free(ovl_aio_request_cachep, aio_req);
+ ovl_aio_put(aio_req);
}
static void ovl_aio_rw_complete(struct kiocb *iocb, long res)
@@ -319,7 +327,9 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
aio_req->orig_iocb = iocb;
kiocb_clone(&aio_req->iocb, iocb, real.file);
aio_req->iocb.ki_complete = ovl_aio_rw_complete;
+ refcount_set(&aio_req->ref, 2);
ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter);
+ ovl_aio_put(aio_req);
if (ret != -EIOCBQUEUED)
ovl_aio_cleanup_handler(aio_req);
}
@@ -390,7 +400,9 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
kiocb_clone(&aio_req->iocb, iocb, real.file);
aio_req->iocb.ki_flags = ifl;
aio_req->iocb.ki_complete = ovl_aio_rw_complete;
+ refcount_set(&aio_req->ref, 2);
ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter);
+ ovl_aio_put(aio_req);
if (ret != -EIOCBQUEUED)
ovl_aio_cleanup_handler(aio_req);
}
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 832b17589733..1f36158c7dbe 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -610,7 +610,10 @@ int ovl_real_fileattr_get(struct path *realpath, struct fileattr *fa)
if (err)
return err;
- return vfs_fileattr_get(realpath->dentry, fa);
+ err = vfs_fileattr_get(realpath->dentry, fa);
+ if (err == -ENOIOCTLCMD)
+ err = -ENOTTY;
+ return err;
}
int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa)
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 3894f3347955..2cd5741c873b 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -570,6 +570,7 @@ struct ovl_cattr {
#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
+int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry, umode_t mode);
struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry,
struct ovl_cattr *attr);
int ovl_cleanup(struct inode *dir, struct dentry *dentry);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 178daa5e82c9..265181c110ae 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -787,10 +787,14 @@ retry:
goto retry;
}
- work = ovl_create_real(dir, work, OVL_CATTR(attr.ia_mode));
- err = PTR_ERR(work);
- if (IS_ERR(work))
- goto out_err;
+ err = ovl_mkdir_real(dir, &work, attr.ia_mode);
+ if (err)
+ goto out_dput;
+
+ /* Weird filesystem returning with hashed negative (kernfs)? */
+ err = -EINVAL;
+ if (d_really_is_negative(work))
+ goto out_dput;
/*
* Try to remove POSIX ACL xattrs from workdir. We are good if: