linux-kernel - Re: [PATCH 1/2] drm/i915: set O_LARGEFILE in __create

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aJtJpCD9-K2Pgsqo@intel.com>
Date: Tue, 12 Aug 2025 10:03:16 -0400
From: Rodrigo Vivi <rodrigo.vivi@...el.com>
To: 陈涛涛 Taotao Chen <chentaotao@...iglobal.com>, "Matthew
 Auld" <matthew.auld@...el.com>
CC: "jani.nikula@...ux.intel.com" <jani.nikula@...ux.intel.com>,
	"joonas.lahtinen@...ux.intel.com" <joonas.lahtinen@...ux.intel.com>,
	"tursulin@...ulin.net" <tursulin@...ulin.net>, "airlied@...il.com"
	<airlied@...il.com>, "simona@...ll.ch" <simona@...ll.ch>,
	"oe-lkp@...ts.linux.dev" <oe-lkp@...ts.linux.dev>, "lkp@...el.com"
	<lkp@...el.com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "intel-gfx@...ts.freedesktop.org"
	<intel-gfx@...ts.freedesktop.org>, "brauner@...nel.org" <brauner@...nel.org>,
	"oliver.sang@...el.com" <oliver.sang@...el.com>
Subject: Re: [PATCH 1/2] drm/i915: set O_LARGEFILE in __create_shmem()

On Mon, Aug 11, 2025 at 09:30:55AM +0000, 陈涛涛 Taotao Chen wrote:
> From: Taotao Chen <chentaotao@...iglobal.com>
> 
> Without O_LARGEFILE, file->f_op->write_iter calls
> generic_write_check_limits(), which enforces a 2GB (MAX_NON_LFS) limit,
> causing -EFBIG on large writes.
> 
> In shmem_pwrite(), this error is later masked as -EIO due to the error
> handling order, leading to igt failures like gen9_exec_parse(bb-large).
> 
> Set O_LARGEFILE in __create_shmem() to prevent -EFBIG on large writes.
> 
> Reported-by: kernel test robot <oliver.sang@...el.com>
> Closes: https://lore.kernel.org/oe-lkp/202508081029.343192ec-lkp@intel.com
> Fixes: 048832a3f400 ("drm/i915: Refactor shmem_pwrite() to use kiocb and write_iter")
> Signed-off-by: Taotao Chen <chentaotao@...iglobal.com>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> index e3d188455f67..2b53aad915f5 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> @@ -514,6 +514,11 @@ static int __create_shmem(struct drm_i915_private *i915,
>  	if (IS_ERR(filp))
>  		return PTR_ERR(filp);
>  
> +	/*
> +	 * Prevent -EFBIG by allowing large writes beyond MAX_NON_LFS on shmem
> +	 * objects by setting O_LARGEFILE.
> +	 */
> +	filp->f_flags |= O_LARGEFILE;

honest question, is it safe to set this here unconditionally?

Cc: Matthew Auld <matthew.auld@...el.com>

>  	obj->filp = filp;
>  	return 0;
>  }
> -- 
> 2.34.1