Fix remount races with symlink handling in affs
A couple of fields in affs_sb_info is used in follow_link() and
symlink() for handling AFFS "absolute" symlinks. Need locking
against affs_remount() updates.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/affs/namei.c b/fs/affs/namei.c
index 960d336..d70bbba 100644
--- a/fs/affs/namei.c
+++ b/fs/affs/namei.c
@@ -341,10 +341,13 @@
p = (char *)AFFS_HEAD(bh)->table;
lc = '/';
if (*symname == '/') {
+ struct affs_sb_info *sbi = AFFS_SB(sb);
while (*symname == '/')
symname++;
- while (AFFS_SB(sb)->s_volume[i]) /* Cannot overflow */
- *p++ = AFFS_SB(sb)->s_volume[i++];
+ spin_lock(&sbi->symlink_lock);
+ while (sbi->s_volume[i]) /* Cannot overflow */
+ *p++ = sbi->s_volume[i++];
+ spin_unlock(&sbi->symlink_lock);
}
while (i < maxlen && (c = *symname++)) {
if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') {