Add the __counted_by compiler attribute to the flexible array member
array to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.
Increment size before adding a new struct to the array.
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxxx>
---
fs/nfs/dir.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 4cb97ef41350..492cffd9d3d8 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -151,7 +151,7 @@ struct nfs_cache_array {
unsigned char folio_full : 1,
folio_is_eof : 1,
cookies_are_ordered : 1;
- struct nfs_cache_array_entry array[];
+ struct nfs_cache_array_entry array[] __counted_by(size);
};
struct nfs_readdir_descriptor {
@@ -328,7 +328,8 @@ static int nfs_readdir_folio_array_append(struct folio *folio,
goto out;
}
- cache_entry = &array->array[array->size];
+ array->size++;
+ cache_entry = &array->array[array->size - 1];
cache_entry->cookie = array->last_cookie;
cache_entry->ino = entry->ino;
cache_entry->d_type = entry->d_type;
@@ -337,7 +338,6 @@ static int nfs_readdir_folio_array_append(struct folio *folio,
array->last_cookie = entry->cookie;
if (array->last_cookie <= cache_entry->cookie)
array->cookies_are_ordered = 0;
- array->size++;
if (entry->eof != 0)
nfs_readdir_array_set_eof(array);
out:
--
2.46.0
