diff options
| author | Bob Peterson <rpeterso@redhat.com> | 2019-11-19 11:40:46 -0500 |
|---|---|---|
| committer | Andreas Gruenbacher <agruenba@redhat.com> | 2019-11-19 21:02:01 +0100 |
| commit | 2c47c1be51fbded1f7baa2ceaed90f97932f79be (patch) | |
| tree | dd4a9ef55e8788f8ca113ec03aca7d0a34d78870 /fs/gfs2 | |
| parent | d99724c3c36ae73ed3908f5e3f2d103a48cd9ad0 (diff) | |
gfs2: clean up iopen glock mess in gfs2_create_inode
Before this patch, gfs2_create_inode had a use-after-free for the
iopen glock in some error paths because it did this:
gfs2_glock_put(io_gl);
fail_gunlock2:
if (io_gl)
clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
In some cases, the io_gl was used for create and only had one
reference, so the glock might be freed before the clear_bit().
This patch tries to straighten it out by only jumping to the
error paths where iopen is properly set, and moving the
gfs2_glock_put after the clear_bit.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Diffstat (limited to 'fs/gfs2')
| -rw-r--r-- | fs/gfs2/inode.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index dcb5d363f9b9..4a1039c41c69 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -712,7 +712,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, error = gfs2_trans_begin(sdp, blocks, 0); if (error) - goto fail_gunlock2; + goto fail_free_inode; if (blocks > 1) { ip->i_eattr = ip->i_no_addr + 1; @@ -723,7 +723,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl); if (error) - goto fail_gunlock2; + goto fail_free_inode; BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags)); @@ -732,7 +732,6 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, goto fail_gunlock2; glock_set_object(ip->i_iopen_gh.gh_gl, ip); - gfs2_glock_put(io_gl); gfs2_set_iop(inode); insert_inode_hash(inode); @@ -765,6 +764,8 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, mark_inode_dirty(inode); d_instantiate(dentry, inode); + /* After instantiate, errors should result in evict which will destroy + * both inode and iopen glocks properly. */ if (file) { file->f_mode |= FMODE_CREATED; error = finish_open(file, dentry, gfs2_open_common); @@ -772,15 +773,15 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, gfs2_glock_dq_uninit(ghs); gfs2_glock_dq_uninit(ghs + 1); clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags); + gfs2_glock_put(io_gl); return error; fail_gunlock3: glock_clear_object(io_gl, ip); gfs2_glock_dq_uninit(&ip->i_iopen_gh); - gfs2_glock_put(io_gl); fail_gunlock2: - if (io_gl) - clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags); + clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags); + gfs2_glock_put(io_gl); fail_free_inode: if (ip->i_gl) { glock_clear_object(ip->i_gl, ip); |