From: Bernd Schubert <bschubert@ddn.com> mainline inclusion from mainline-v6.11-rc7 commit 3ab394b363c5fd14b231e335fb6746ddfb93aaaa category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBHLU4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Current design and handling of passthrough is without fuse caching and with that FUSE_WRITEBACK_CACHE is conflicting. Fixes: 7dc4e97a4f9a ("fuse: introduce FUSE_PASSTHROUGH capability") Cc: stable@kernel.org # v6.9 Signed-off-by: Bernd Schubert <bschubert@ddn.com> Acked-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- fs/fuse/inode.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index a5617b04ebcb..d771ce993e3e 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1333,11 +1333,16 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, * on a stacked fs (e.g. overlayfs) themselves and with * max_stack_depth == 1, FUSE fs can be stacked as the * underlying fs of a stacked fs (e.g. overlayfs). + * + * Also don't allow the combination of FUSE_PASSTHROUGH + * and FUSE_WRITEBACK_CACHE, current design doesn't handle + * them together. */ if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH) && (flags & FUSE_PASSTHROUGH) && arg->max_stack_depth > 0 && - arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH) { + arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH && + !(flags & FUSE_WRITEBACK_CACHE)) { fc->passthrough = 1; fc->max_stack_depth = arg->max_stack_depth; fm->sb->s_stack_depth = arg->max_stack_depth; -- 2.39.2