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***
Subject:
Author: jkoolstra@xs4all.nl
#syz test
---
diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index d54273c3c9ff..ce62cb61186d 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -168,4 +168,6 @@ static inline int minix_test_bit(int nr, const void *vaddr)
#endif
+#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
+
#endif /* FS_MINIX_H */
diff --git a/fs/minix/namei.c b/fs/minix/namei.c
index a8d5a7e22b7b..f18f7474aca4 100644
--- a/fs/minix/namei.c
+++ b/fs/minix/namei.c
@@ -145,6 +145,12 @@ static int minix_unlink(struct inode * dir, struct dentry *dentry)
struct minix_dir_entry * de;
int err;
+ if (inode->i_nlink < 1) {
+ printk(KERN_CRIT "minix-fs error: inode (ino: %ld) "
+ "has corrupted nlink", inode->i_ino);
+ return -EFSCORRUPTED;
+ }
+
de = minix_find_entry(dentry, &folio);
if (!de)
return -ENOENT;
@@ -218,6 +224,13 @@ static int minix_rename(struct mnt_idmap *idmap,
if (dir_de && !minix_empty_dir(new_inode))
goto out_dir;
+ err = -EFSCORRUPTED;
+ if (new_inode->i_nlink == 0 || (dir_de && new_inode->i_nlink != 2)) {
+ printk(KERN_CRIT "minix-fs error: inode (ino: %ld) "
+ "has corrupted nlink", new_inode->i_ino);
+ goto out_dir;
+ }
+
err = -ENOENT;
new_de = minix_find_entry(new_dentry, &new_folio);
if (!new_de)