From ec275bf9693d19cc0fdce8436f4c425ced86f6e7 Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai Date: Wed, 11 Jan 2023 16:59:43 +0800 Subject: fs/ntfs3: Fix a possible null-pointer dereference in ni_clear() In a previous commit c1006bd13146, ni->mi.mrec in ni_write_inode() could be NULL, and thus a NULL check is added for this variable. However, in the same call stack, ni->mi.mrec can be also dereferenced in ni_clear(): ntfs_evict_inode(inode) ni_write_inode(inode, ...) ni = ntfs_i(inode); is_rec_inuse(ni->mi.mrec) -> Add a NULL check by previous commit ni_clear(ntfs_i(inode)) is_rec_inuse(ni->mi.mrec) -> No check Thus, a possible null-pointer dereference may exist in ni_clear(). To fix it, a NULL check is added in this function. Signed-off-by: Jia-Ju Bai Reported-by: TOTE Robot Signed-off-by: Konstantin Komarov --- fs/ntfs3/frecord.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ntfs3/frecord.c') diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c index 1103d4d9a497..9e7dfee303e8 100644 --- a/fs/ntfs3/frecord.c +++ b/fs/ntfs3/frecord.c @@ -102,7 +102,7 @@ void ni_clear(struct ntfs_inode *ni) { struct rb_node *node; - if (!ni->vfs_inode.i_nlink && is_rec_inuse(ni->mi.mrec)) + if (!ni->vfs_inode.i_nlink && ni->mi.mrec && is_rec_inuse(ni->mi.mrec)) ni_delete_all(ni); al_destroy(ni); -- cgit v1.2.3