vfs: Fix O_NOFOLLOW behavior for paths with trailing slashes
According to specification
mkdir d; ln -s d a; open("a/", O_NOFOLLOW | O_RDONLY)
should return success but currently it returns ELOOP. This is a
regression caused by path lookup cleanup patch series.
Fix the code to ignore O_NOFOLLOW in case the provided path has trailing
slashes.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: Marius Tolzmann <tolzmann@molgen.mpg.de>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/namei.c b/fs/namei.c
index a7dce91..16df7277 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1641,7 +1641,7 @@
if (nd->last.name[nd->last.len]) {
if (open_flag & O_CREAT)
goto exit;
- nd->flags |= LOOKUP_DIRECTORY;
+ nd->flags |= LOOKUP_DIRECTORY | LOOKUP_FOLLOW;
}
/* just plain open? */
@@ -1830,6 +1830,8 @@
}
if (open_flag & O_DIRECTORY)
nd.flags |= LOOKUP_DIRECTORY;
+ if (!(open_flag & O_NOFOLLOW))
+ nd.flags |= LOOKUP_FOLLOW;
filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
while (unlikely(!filp)) { /* trailing symlink */
struct path holder;
@@ -1837,7 +1839,7 @@
void *cookie;
error = -ELOOP;
/* S_ISDIR part is a temporary automount kludge */
- if ((open_flag & O_NOFOLLOW) && !S_ISDIR(inode->i_mode))
+ if (!(nd.flags & LOOKUP_FOLLOW) && !S_ISDIR(inode->i_mode))
goto exit_dput;
if (count++ == 32)
goto exit_dput;