Re: [PATCH] 9p: fix memory leak in v9fs_init_fs_context error path

[Christian Schoenebeck]

On Wednesday, 25 February 2026 14:57:45 CET Sasha Levin wrote:
> Move the assignments of fc->ops and fc->fs_private to right after the
> kzalloc, before any fallible operations. Previously these were assigned
> at the end of the function, after the kstrdup calls for uname and aname.
> If either kstrdup failed, the error path would set fc->need_free but
> leave fc->ops NULL, so put_fs_context() would never call v9fs_free_fc()
> to free the allocated context and any already-duplicated strings.
> 
> Fixes: 1f3e4142c0eb ("9p: convert to the new mount API")
> Assisted-by: Claude:claude-opus-4-6
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
>  fs/9p/vfs_super.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Reviewed-by: Christian Schoenebeck <linux_oss@xxxxxxxxxxxxx>
 
> diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
> index 0a1c4f7cb001d..431f24938a1d3 100644
> --- a/fs/9p/vfs_super.c
> +++ b/fs/9p/vfs_super.c
> @@ -312,6 +312,9 @@ static int v9fs_init_fs_context(struct fs_context *fc)
>  	if (!ctx)
>  		return -ENOMEM;
> 
> +	fc->ops = &v9fs_context_ops;
> +	fc->fs_private = ctx;
> +
>  	/* initialize core options */
>  	ctx->session_opts.afid = ~0;
>  	ctx->session_opts.cache = CACHE_NONE;
> @@ -345,9 +348,6 @@ static int v9fs_init_fs_context(struct fs_context *fc)
>  	ctx->rdma_opts.timeout = P9_RDMA_TIMEOUT;
>  	ctx->rdma_opts.privport = false;
> 
> -	fc->ops = &v9fs_context_ops;
> -	fc->fs_private = ctx;
> -
>  	return 0;
>  error:
>  	fc->need_free = 1;