From 5cadfbd5a11e5495cac217534c5f788168b1afd7 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Mon, 27 Mar 2023 16:14:49 +0200 Subject: [PATCH 1/5] fuse: add feature flag for expire-only Add an init flag idicating whether the FUSE_EXPIRE_ONLY flag of FUSE_NOTIFY_INVAL_ENTRY is effective. This is needed for backports of this feature, otherwise the server could just check the protocol version. Fixes: 4f8d37020e1f ("fuse: add "expire only" mode to FUSE_NOTIFY_INVAL_ENTRY") Cc: # v6.2 Signed-off-by: Miklos Szeredi --- fs/fuse/inode.c | 3 ++- include/uapi/linux/fuse.h | 3 +++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index d66070af145d..660be31aaabc 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1254,7 +1254,8 @@ void fuse_send_init(struct fuse_mount *fm) FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS | FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT | - FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP; + FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP | + FUSE_HAS_EXPIRE_ONLY; #ifdef CONFIG_FUSE_DAX if (fm->fc->dax) flags |= FUSE_MAP_ALIGNMENT; diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 1b9d0dfae72d..b3fcab13fcd3 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -206,6 +206,7 @@ * - add extension header * - add FUSE_EXT_GROUPS * - add FUSE_CREATE_SUPP_GROUP + * - add FUSE_HAS_EXPIRE_ONLY */ #ifndef _LINUX_FUSE_H @@ -369,6 +370,7 @@ struct fuse_file_lock { * FUSE_HAS_INODE_DAX: use per inode DAX * FUSE_CREATE_SUPP_GROUP: add supplementary group info to create, mkdir, * symlink and mknod (single group that matches parent) + * FUSE_HAS_EXPIRE_ONLY: kernel supports expiry-only entry invalidation */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -406,6 +408,7 @@ struct fuse_file_lock { #define FUSE_SECURITY_CTX (1ULL << 32) #define FUSE_HAS_INODE_DAX (1ULL << 33) #define FUSE_CREATE_SUPP_GROUP (1ULL << 34) +#define FUSE_HAS_EXPIRE_ONLY (1ULL << 35) /** * CUSE INIT request/reply flags From 1c3610d30e5c15f4db7eb8465e311b582aa50ebe Mon Sep 17 00:00:00 2001 From: zyfjeff Date: Tue, 13 Dec 2022 19:51:47 +0800 Subject: [PATCH 2/5] fuse: remove duplicate check for nodeid before this check, the nodeid has already been checked once, so the check here doesn't make an sense, so remove the check for nodeid here. if (err || !outarg->nodeid) goto out_put_forget; err = -EIO; >>> if (!outarg->nodeid) goto out_put_forget; Signed-off-by: zyfjeff Signed-off-by: Miklos Szeredi --- fs/fuse/dir.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 35bc174f9ba2..5a4a7155cf1c 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -395,8 +395,6 @@ int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name goto out_put_forget; err = -EIO; - if (!outarg->nodeid) - goto out_put_forget; if (fuse_invalid_attr(&outarg->attr)) goto out_put_forget; From 3066ff93476c35679cb07a97cce37d9bb07632ff Mon Sep 17 00:00:00 2001 From: Bernd Schubert Date: Fri, 15 Apr 2022 13:53:56 +0200 Subject: [PATCH 3/5] fuse: Apply flags2 only when userspace set the FUSE_INIT_EXT This is just a safety precaution to avoid checking flags on memory that was initialized on the user space side. libfuse zeroes struct fuse_init_out outarg, but this is not guranteed to be done in all implementations. Better is to act on flags and to only apply flags2 when FUSE_INIT_EXT is set. There is a risk with this change, though - it might break existing user space libraries, which are already using flags2 without setting FUSE_INIT_EXT. The corresponding libfuse patch is here https://github.com/libfuse/libfuse/pull/662 Signed-off-by: Bernd Schubert Fixes: 53db28933e95 ("fuse: extend init flags") Cc: # v5.17 Signed-off-by: Miklos Szeredi --- fs/fuse/inode.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 660be31aaabc..f19d748890f0 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1134,7 +1134,10 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, process_init_limits(fc, arg); if (arg->minor >= 6) { - u64 flags = arg->flags | (u64) arg->flags2 << 32; + u64 flags = arg->flags; + + if (flags & FUSE_INIT_EXT) + flags |= (u64) arg->flags2 << 32; ra_pages = arg->max_readahead / PAGE_SIZE; if (flags & FUSE_ASYNC_READ) From a9d1c4c6df0e568207907c04aed9e7beb1294c42 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 7 Jun 2023 17:49:20 +0200 Subject: [PATCH 4/5] fuse: revalidate: don't invalidate if interrupted If the LOOKUP request triggered from fuse_dentry_revalidate() is interrupted, then the dentry will be invalidated, possibly resulting in submounts being unmounted. Reported-by: Xu Rongbo Closes: https://lore.kernel.org/all/CAJfpegswN_CJJ6C3RZiaK6rpFmNyWmXfaEpnQUJ42KCwNF5tWw@mail.gmail.com/ Fixes: 9e6268db496a ("[PATCH] FUSE - read-write operations") Cc: Signed-off-by: Miklos Szeredi --- fs/fuse/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 5a4a7155cf1c..f67bef9d83c4 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -258,7 +258,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags) spin_unlock(&fi->lock); } kfree(forget); - if (ret == -ENOMEM) + if (ret == -ENOMEM || ret == -EINTR) goto out; if (ret || fuse_invalid_attr(&outarg.attr) || fuse_stale_inode(inode, outarg.generation, &outarg.attr)) From 6a567e920fd0451bf29abc418df96c3365925770 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 7 Jun 2023 17:49:21 +0200 Subject: [PATCH 5/5] fuse: ioctl: translate ENOSYS in outarg Fuse shouldn't return ENOSYS from its ioctl implementation. If userspace responds with ENOSYS it should be translated to ENOTTY. There are two ways to return an error from the IOCTL request: - fuse_out_header.error - fuse_ioctl_out.result Commit 02c0cab8e734 ("fuse: ioctl: translate ENOSYS") already fixed this issue for the first case, but missed the second case. This patch fixes the second case. Reported-by: Jonathan Katz Closes: https://lore.kernel.org/all/CALKgVmcC1VUV_gJVq70n--omMJZUb4HSh_FqvLTHgNBc+HCLFQ@mail.gmail.com/ Fixes: 02c0cab8e734 ("fuse: ioctl: translate ENOSYS") Cc: Signed-off-by: Miklos Szeredi --- fs/fuse/ioctl.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/fs/fuse/ioctl.c b/fs/fuse/ioctl.c index 8e01bfdfc430..726640fa439e 100644 --- a/fs/fuse/ioctl.c +++ b/fs/fuse/ioctl.c @@ -9,14 +9,23 @@ #include #include -static ssize_t fuse_send_ioctl(struct fuse_mount *fm, struct fuse_args *args) +static ssize_t fuse_send_ioctl(struct fuse_mount *fm, struct fuse_args *args, + struct fuse_ioctl_out *outarg) { - ssize_t ret = fuse_simple_request(fm, args); + ssize_t ret; + + args->out_args[0].size = sizeof(*outarg); + args->out_args[0].value = outarg; + + ret = fuse_simple_request(fm, args); /* Translate ENOSYS, which shouldn't be returned from fs */ if (ret == -ENOSYS) ret = -ENOTTY; + if (ret >= 0 && outarg->result == -ENOSYS) + outarg->result = -ENOTTY; + return ret; } @@ -264,13 +273,11 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, } ap.args.out_numargs = 2; - ap.args.out_args[0].size = sizeof(outarg); - ap.args.out_args[0].value = &outarg; ap.args.out_args[1].size = out_size; ap.args.out_pages = true; ap.args.out_argvar = true; - transferred = fuse_send_ioctl(fm, &ap.args); + transferred = fuse_send_ioctl(fm, &ap.args, &outarg); err = transferred; if (transferred < 0) goto out; @@ -399,12 +406,10 @@ static int fuse_priv_ioctl(struct inode *inode, struct fuse_file *ff, args.in_args[1].size = inarg.in_size; args.in_args[1].value = ptr; args.out_numargs = 2; - args.out_args[0].size = sizeof(outarg); - args.out_args[0].value = &outarg; args.out_args[1].size = inarg.out_size; args.out_args[1].value = ptr; - err = fuse_send_ioctl(fm, &args); + err = fuse_send_ioctl(fm, &args, &outarg); if (!err) { if (outarg.result < 0) err = outarg.result;