From: Al Viro <viro@zeniv.linux.org.uk>
Date: Tue, 24 Nov 2015 02:11:08 +0000 (-0500)
Subject: fix sysvfs symlinks
X-Git-Tag: v2.6.32.70~29
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=54146dba78db0ee7ff31cb8311c78aebfd21c2ba;p=thirdparty%2Fkernel%2Fstable.git

fix sysvfs symlinks

commit 0ebf7f10d67a70e120f365018f1c5fce9ddc567d upstream.

The thing got broken back in 2002 - sysvfs does *not* have inline
symlinks; even short ones have bodies stored in the first block
of file.  sysv_symlink() handles that correctly; unfortunately,
attempting to look an existing symlink up will end up confusing
them for inline symlinks, and interpret the block number containing
the body as the body itself.

Nobody has noticed until now, which says something about the level
of testing sysvfs gets ;-/

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.2:
 - Adjust context
 - Also delete unused sysv_fast_symlink_inode_operations]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
(cherry picked from commit 081c769778f7a41f4eb3d633df26ad572575c980)
Signed-off-by: Willy Tarreau <w@1wt.eu>
---

diff --git a/fs/sysv/Makefile b/fs/sysv/Makefile
index 3591f9d7a48a4..7a75e70a4b61b 100644
--- a/fs/sysv/Makefile
+++ b/fs/sysv/Makefile
@@ -5,4 +5,4 @@
 obj-$(CONFIG_SYSV_FS) += sysv.o
 
 sysv-objs := ialloc.o balloc.o inode.o itree.o file.o dir.o \
-	     namei.o super.o symlink.o
+	     namei.o super.o
diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index 9824743832a72..cea880427b0c9 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -174,14 +174,8 @@ void sysv_set_inode(struct inode *inode, dev_t rdev)
 		inode->i_fop = &sysv_dir_operations;
 		inode->i_mapping->a_ops = &sysv_aops;
 	} else if (S_ISLNK(inode->i_mode)) {
-		if (inode->i_blocks) {
-			inode->i_op = &sysv_symlink_inode_operations;
-			inode->i_mapping->a_ops = &sysv_aops;
-		} else {
-			inode->i_op = &sysv_fast_symlink_inode_operations;
-			nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size,
-				sizeof(SYSV_I(inode)->i_data) - 1);
-		}
+		inode->i_op = &sysv_symlink_inode_operations;
+		inode->i_mapping->a_ops = &sysv_aops;
 	} else
 		init_special_inode(inode, inode->i_mode, rdev);
 }
diff --git a/fs/sysv/symlink.c b/fs/sysv/symlink.c
deleted file mode 100644
index 00d2f8a43e4ea..0000000000000
--- a/fs/sysv/symlink.c
+++ /dev/null
@@ -1,20 +0,0 @@
-/*
- *  linux/fs/sysv/symlink.c
- *
- *  Handling of System V filesystem fast symlinks extensions.
- *  Aug 2001, Christoph Hellwig (hch@infradead.org)
- */
-
-#include "sysv.h"
-#include <linux/namei.h>
-
-static void *sysv_follow_link(struct dentry *dentry, struct nameidata *nd)
-{
-	nd_set_link(nd, (char *)SYSV_I(dentry->d_inode)->i_data);
-	return NULL;
-}
-
-const struct inode_operations sysv_fast_symlink_inode_operations = {
-	.readlink	= generic_readlink,
-	.follow_link	= sysv_follow_link,
-};