Commit e22c3872 authored by Azeem Shaikh's avatar Azeem Shaikh Committed by Andrew Morton
Browse files

fs: ocfs2: replace strlcpy with sysfs_emit 

strlcpy() reads the entire source buffer first.  This read may exceed the
destination size limit.  This is both inefficient and can lead to linear
read overflows if a source string is not NUL-terminated [1].  In an effort
to remove strlcpy() completely [2], replace strlcpy() here with
sysfs_emit().

Direct replacement is safe here since its ok for `kernel_param_ops.get()`
to return -errno [3].

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
[3] https://elixir.bootlin.com/linux/v6.5/source/include/linux/moduleparam.h#L52

Link: https://lkml.kernel.org/r/20230831193827.1528867-1-azeemshaikh38@gmail.com


Signed-off-by: default avatarAzeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarJoseph Qi <joseph.qi@linux.alibaba.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent f6e9d38f

fs/ocfs2/dlmfs/dlmfs.c

+1 −2
Original line number Diff line number Diff line
@@ -80,8 +80,7 @@ static int param_set_dlmfs_capabilities(const char *val, 
static int param_get_dlmfs_capabilities(char *buffer,

					const struct kernel_param *kp)

{

	return strlcpy(buffer, DLMFS_CAPABILITIES,

		       strlen(DLMFS_CAPABILITIES) + 1);

	return sysfs_emit(buffer, DLMFS_CAPABILITIES);

}

module_param_call(capabilities, param_set_dlmfs_capabilities,

		  param_get_dlmfs_capabilities, NULL, 0444);