From 474740b9e629cad9479324efd3926a8e88b04761 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 24 Sep 2014 17:56:17 +0200 Subject: shmem: fix nlink for rename overwrite directory commit b928095b0a7cff7fb9fcf4c706348ceb8ab2c295 upstream. If overwriting an empty directory with rename, then need to drop the extra nlink. Test prog: #include #include #include #include int main(void) { const char *test_dir1 = "test-dir1"; const char *test_dir2 = "test-dir2"; int res; int fd; struct stat statbuf; res = mkdir(test_dir1, 0777); if (res == -1) err(1, "mkdir(\"%s\")", test_dir1); res = mkdir(test_dir2, 0777); if (res == -1) err(1, "mkdir(\"%s\")", test_dir2); fd = open(test_dir2, O_RDONLY); if (fd == -1) err(1, "open(\"%s\")", test_dir2); res = rename(test_dir1, test_dir2); if (res == -1) err(1, "rename(\"%s\", \"%s\")", test_dir1, test_dir2); res = fstat(fd, &statbuf); if (res == -1) err(1, "fstat(%i)", fd); if (statbuf.st_nlink != 0) { fprintf(stderr, "nlink is %lu, should be 0\n", statbuf.st_nlink); return 1; } return 0; } Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- mm/shmem.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/mm/shmem.c b/mm/shmem.c index 16cc1d77f70..4e4a7349c5c 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2128,8 +2128,10 @@ static int shmem_rename(struct inode *old_dir, struct dentry *old_dentry, struct if (new_dentry->d_inode) { (void) shmem_unlink(new_dir, new_dentry); - if (they_are_dirs) + if (they_are_dirs) { + drop_nlink(new_dentry->d_inode); drop_nlink(old_dir); + } } else if (they_are_dirs) { drop_nlink(old_dir); inc_nlink(new_dir); -- cgit v1.2.3