From 6cf32607555da7ef99005ff0d73f3d8597cbbd04 Mon Sep 17 00:00:00 2001 From: Thorsten Blum Date: Sat, 8 Nov 2025 13:07:40 +0100 Subject: [PATCH] crypto: zstd - Annotate struct zstd_ctx with __counted_by Add the __counted_by() compiler attribute to the flexible array member 'wksp' to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE. Use struct_size(), which provides additional compile-time checks for structures with flexible array members (e.g., __must_be_array()), for the allocation size for a new 'zstd_ctx' while we're at it. Signed-off-by: Thorsten Blum Reviewed-by: David Sterba Signed-off-by: Herbert Xu --- crypto/zstd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/crypto/zstd.c b/crypto/zstd.c index ac318d333b684..ace7a82ea45a9 100644 --- a/crypto/zstd.c +++ b/crypto/zstd.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -25,7 +26,7 @@ struct zstd_ctx { zstd_dctx *dctx; size_t wksp_size; zstd_parameters params; - u8 wksp[] __aligned(8); + u8 wksp[] __aligned(8) __counted_by(wksp_size); }; static DEFINE_MUTEX(zstd_stream_lock); @@ -44,7 +45,7 @@ static void *zstd_alloc_stream(void) if (!wksp_size) return ERR_PTR(-EINVAL); - ctx = kvmalloc(sizeof(*ctx) + wksp_size, GFP_KERNEL); + ctx = kvmalloc(struct_size(ctx, wksp, wksp_size), GFP_KERNEL); if (!ctx) return ERR_PTR(-ENOMEM); -- 2.47.3