+++ /dev/null
-From 7077fffcb0b0b65dc75e341306aeef4d0e7f2ec6 Mon Sep 17 00:00:00 2001
-From: Gao Xiang <gaoxiang25@huawei.com>
-Date: Mon, 14 Jan 2019 19:40:23 +0800
-Subject: staging: erofs: fix fast symlink w/o xattr when fs xattr is on
-
-From: Gao Xiang <gaoxiang25@huawei.com>
-
-commit 7077fffcb0b0b65dc75e341306aeef4d0e7f2ec6 upstream.
-
-Currently, this will hit a BUG_ON for these symlinks as follows:
-
-- kernel message
-------------[ cut here ]------------
-kernel BUG at drivers/staging/erofs/xattr.c:59!
-SMP PTI
-CPU: 1 PID: 1170 Comm: getllxattr Not tainted 4.20.0-rc6+ #92
-Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
-RIP: 0010:init_inode_xattrs+0x22b/0x270
-Code: 48 0f 45 ea f0 ff 4d 34 74 0d 41 83 4c 24 e0 01 31 c0 e9 00 fe ff ff 48 89 ef e8 e0 31 9e ff eb e9 89 e8 e9 ef fd ff ff 0f 0$
- <0f> 0b 48 89 ef e8 fb f6 9c ff 48 8b 45 08 a8 01 75 24 f0 ff 4d 34
-RSP: 0018:ffffa03ac026bdf8 EFLAGS: 00010246
-------------[ cut here ]------------
-...
-Call Trace:
- erofs_listxattr+0x30/0x2c0
- ? selinux_inode_listxattr+0x5a/0x80
- ? kmem_cache_alloc+0x33/0x170
- ? security_inode_listxattr+0x27/0x40
- listxattr+0xaf/0xc0
- path_listxattr+0x5a/0xa0
- do_syscall_64+0x43/0xf0
- entry_SYSCALL_64_after_hwframe+0x44/0xa9
-...
----[ end trace 3c24b49408dc0c72 ]---
-
-Fix it by checking ->xattr_isize in init_inode_xattrs(),
-and it also fixes improper return value -ENOTSUPP
-(it should be -ENODATA if xattr is enabled) for those inodes.
-
-Fixes: b17500a0fdba ("staging: erofs: introduce xattr & acl support")
-Cc: <stable@vger.kernel.org> # 4.19+
-Reported-by: Li Guifu <bluce.liguifu@huawei.com>
-Tested-by: Li Guifu <bluce.liguifu@huawei.com>
-Reviewed-by: Chao Yu <yuchao0@huawei.com>
-Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
----
- drivers/staging/erofs/inode.c | 8 ++++----
- drivers/staging/erofs/xattr.c | 25 ++++++++++++++++++++-----
- 2 files changed, 24 insertions(+), 9 deletions(-)
-
---- a/drivers/staging/erofs/inode.c
-+++ b/drivers/staging/erofs/inode.c
-@@ -184,16 +184,16 @@ static int fill_inode(struct inode *inod
- /* setup the new inode */
- if (S_ISREG(inode->i_mode)) {
- #ifdef CONFIG_EROFS_FS_XATTR
-- if (vi->xattr_isize)
-- inode->i_op = &erofs_generic_xattr_iops;
-+ inode->i_op = &erofs_generic_xattr_iops;
- #endif
- inode->i_fop = &generic_ro_fops;
- } else if (S_ISDIR(inode->i_mode)) {
- inode->i_op =
- #ifdef CONFIG_EROFS_FS_XATTR
-- vi->xattr_isize ? &erofs_dir_xattr_iops :
--#endif
-+ &erofs_dir_xattr_iops;
-+#else
- &erofs_dir_iops;
-+#endif
- inode->i_fop = &erofs_dir_fops;
- } else if (S_ISLNK(inode->i_mode)) {
- /* by default, page_get_link is used for symlink */
---- a/drivers/staging/erofs/xattr.c
-+++ b/drivers/staging/erofs/xattr.c
-@@ -46,7 +46,26 @@ static void init_inode_xattrs(struct ino
- return;
-
- vi = EROFS_V(inode);
-- BUG_ON(!vi->xattr_isize);
-+
-+ /*
-+ * bypass all xattr operations if ->xattr_isize is not greater than
-+ * sizeof(struct erofs_xattr_ibody_header), in detail:
-+ * 1) it is not enough to contain erofs_xattr_ibody_header then
-+ * ->xattr_isize should be 0 (it means no xattr);
-+ * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk
-+ * undefined right now (maybe use later with some new sb feature).
-+ */
-+ if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) {
-+ errln("xattr_isize %d of nid %llu is not supported yet",
-+ vi->xattr_isize, vi->nid);
-+ return -ENOTSUPP;
-+ } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) {
-+ if (unlikely(vi->xattr_isize)) {
-+ DBG_BUGON(1);
-+ return -EIO; /* xattr ondisk layout error */
-+ }
-+ return -ENOATTR;
-+ }
-
- sbi = EROFS_I_SB(inode);
- it.blkaddr = erofs_blknr(iloc(sbi, vi->nid) + vi->inode_isize);
-@@ -374,7 +393,6 @@ static int erofs_xattr_generic_get(const
- struct dentry *unused, struct inode *inode,
- const char *name, void *buffer, size_t size)
- {
-- struct erofs_vnode *const vi = EROFS_V(inode);
- struct erofs_sb_info *const sbi = EROFS_I_SB(inode);
-
- switch (handler->flags) {
-@@ -392,9 +410,6 @@ static int erofs_xattr_generic_get(const
- return -EINVAL;
- }
-
-- if (!vi->xattr_isize)
-- return -ENOATTR;
--
- return erofs_getxattr(inode, handler->flags, name, buffer, size);
- }
-