From d0920a9cd7e735c429c510b523a100db82c937a1 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Fri, 13 Oct 2017 00:39:38 +0200 Subject: gfs2: Allow gfs2_xattr_set to be called with the glock held On the following call path: gfs2_setattr -> setattr_prepare -> ... -> cap_inode_killpriv -> ... -> gfs2_xattr_set the glock is locked in gfs2_setattr, so check for recursive locking in gfs2_xattr_set as gfs2_xattr_get already does. While at it, get rid of need_unlock in gfs2_xattr_get. Fixes xfstest generic/093. Signed-off-by: Andreas Gruenbacher Acked-by: Abhijith Das Signed-off-by: Bob Peterson --- fs/gfs2/xattr.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c index 3e96dce21c1c..05de20954659 100644 --- a/fs/gfs2/xattr.c +++ b/fs/gfs2/xattr.c @@ -610,7 +610,6 @@ static int gfs2_xattr_get(const struct xattr_handler *handler, { struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder gh; - bool need_unlock = false; int ret; /* During lookup, SELinux calls this function with the glock locked. */ @@ -619,10 +618,11 @@ static int gfs2_xattr_get(const struct xattr_handler *handler, ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh); if (ret) return ret; - need_unlock = true; + } else { + gfs2_holder_mark_uninitialized(&gh); } ret = __gfs2_xattr_get(inode, name, buffer, size, handler->flags); - if (need_unlock) + if (gfs2_holder_initialized(&gh)) gfs2_glock_dq_uninit(&gh); return ret; } @@ -1244,11 +1244,20 @@ static int gfs2_xattr_set(const struct xattr_handler *handler, if (ret) return ret; - ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); - if (ret) - return ret; + /* May be called from gfs_setattr with the glock locked. */ + + if (!gfs2_glock_is_locked_by_me(ip->i_gl)) { + ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); + if (ret) + return ret; + } else { + if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE)) + return -EIO; + gfs2_holder_mark_uninitialized(&gh); + } ret = __gfs2_xattr_set(inode, name, value, size, flags, handler->flags); - gfs2_glock_dq_uninit(&gh); + if (gfs2_holder_initialized(&gh)) + gfs2_glock_dq_uninit(&gh); return ret; } -- cgit