tentatively merged into cifs-2.6.git for-next pending more testing
On Wed, Jun 23, 2021 at 5:00 PM Ronnie Sahlberg <lsahlber@xxxxxxxxxx> wrote:
>
> Use the nice helpers to initialize and the uid/gid/cred_uid when passed as mount
> arguments.
> Also, when we duplicate a context, for example in multiuser,cruid=xxx we need to
> re-set these uid/gids to the current user or else we may get a crash.
>
> Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api")
> Cc: stable@xxxxxxxxxxxxxxx # 5.11
> Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> ---
> fs/cifs/fs_context.c | 27 ++++++++++++++++++++++-----
> fs/cifs/fs_context.h | 1 +
> 2 files changed, 23 insertions(+), 5 deletions(-)
>
> diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> index 92d4ab029c91..39bebe298387 100644
> --- a/fs/cifs/fs_context.c
> +++ b/fs/cifs/fs_context.c
> @@ -322,7 +322,9 @@ smb3_fs_context_dup(struct smb3_fs_context *new_ctx, struct smb3_fs_context *ctx
> new_ctx->UNC = NULL;
> new_ctx->source = NULL;
> new_ctx->iocharset = NULL;
> -
> + new_ctx->linux_uid = current_fsuid();
> + new_ctx->cred_uid = current_fsuid();
> + new_ctx->linux_gid = current_fsgid();
> /*
> * Make sure to stay in sync with smb3_cleanup_fs_context_contents()
> */
> @@ -792,6 +794,8 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
> int i, opt;
> bool is_smb3 = !strcmp(fc->fs_type->name, "smb3");
> bool skip_parsing = false;
> + kuid_t uid;
> + kgid_t gid;
>
> cifs_dbg(FYI, "CIFS: parsing cifs mount option '%s'\n", param->key);
>
> @@ -904,18 +908,31 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
> }
> break;
> case Opt_uid:
> - ctx->linux_uid.val = result.uint_32;
> + uid = make_kuid(current_user_ns(), result.uint_32);
> + if (!uid_valid(uid))
> + goto cifs_parse_mount_err;
> + ctx->linux_uid = uid;
> ctx->uid_specified = true;
> break;
> case Opt_cruid:
> - ctx->cred_uid.val = result.uint_32;
> + uid = make_kuid(current_user_ns(), result.uint_32);
> + if (!uid_valid(uid))
> + goto cifs_parse_mount_err;
> + ctx->cred_uid = uid;
> + ctx->cruid_specified = true;
> break;
> case Opt_backupgid:
> - ctx->backupgid.val = result.uint_32;
> + gid = make_kgid(current_user_ns(), result.uint_32);
> + if (!gid_valid(gid))
> + goto cifs_parse_mount_err;
> + ctx->backupgid = gid;
> ctx->backupgid_specified = true;
> break;
> case Opt_gid:
> - ctx->linux_gid.val = result.uint_32;
> + gid = make_kgid(current_user_ns(), result.uint_32);
> + if (!gid_valid(gid))
> + goto cifs_parse_mount_err;
> + ctx->linux_gid = gid;
> ctx->gid_specified = true;
> break;
> case Opt_port:
> diff --git a/fs/cifs/fs_context.h b/fs/cifs/fs_context.h
> index 2a71c8e411ac..b6243972edf3 100644
> --- a/fs/cifs/fs_context.h
> +++ b/fs/cifs/fs_context.h
> @@ -155,6 +155,7 @@ enum cifs_param {
>
> struct smb3_fs_context {
> bool uid_specified;
> + bool cruid_specified;
> bool gid_specified;
> bool sloppy;
> bool got_ip;
> --
> 2.30.2
>
--
Thanks,
Steve
