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author | Miklos Szeredi <mszeredi@redhat.com> | 2022-11-10 17:46:33 +0300 |
---|---|---|
committer | Miklos Szeredi <mszeredi@redhat.com> | 2023-01-26 19:10:37 +0300 |
commit | 15d937d7ca8c55d2b0ce9116e20c780fdd0b67cc (patch) | |
tree | c679eb27d286dc1630806095c040ef3de951247a /fs | |
parent | 1b929c02afd37871d5afb9d498426f83432e71c2 (diff) | |
download | linux-15d937d7ca8c55d2b0ce9116e20c780fdd0b67cc.tar.xz |
fuse: add request extension
Will need to add supplementary groups to create messages, so add the
general concept of a request extension. A request extension is appended to
the end of the main request. It has a header indicating the size and type
of the extension.
The create security context (fuse_secctx_*) is similar to the generic
request extension, so include that as well in a backward compatible manner.
Add the total extension length to the request header. The offset of the
extension block within the request can be calculated by:
inh->len - inh->total_extlen * 8
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/fuse/dev.c | 2 | ||||
-rw-r--r-- | fs/fuse/dir.c | 66 | ||||
-rw-r--r-- | fs/fuse/fuse_i.h | 6 |
3 files changed, 44 insertions, 30 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index e8b60ce72c9a..9f349f834977 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -476,6 +476,8 @@ static void fuse_args_to_req(struct fuse_req *req, struct fuse_args *args) req->in.h.opcode = args->opcode; req->in.h.nodeid = args->nodeid; req->args = args; + if (args->is_ext) + req->in.h.total_extlen = args->in_args[args->ext_idx].size / 8; if (args->end) __set_bit(FR_ASYNC, &req->flags); } diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index cd1a071b625a..fa6381f199b3 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -466,7 +466,7 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, } static int get_security_context(struct dentry *entry, umode_t mode, - void **security_ctx, u32 *security_ctxlen) + struct fuse_in_arg *ext) { struct fuse_secctx *fctx; struct fuse_secctx_header *header; @@ -513,14 +513,42 @@ static int get_security_context(struct dentry *entry, umode_t mode, memcpy(ptr, ctx, ctxlen); } - *security_ctxlen = total_len; - *security_ctx = header; + ext->size = total_len; + ext->value = header; err = 0; out_err: kfree(ctx); return err; } +static int get_create_ext(struct fuse_args *args, struct dentry *dentry, + umode_t mode) +{ + struct fuse_conn *fc = get_fuse_conn_super(dentry->d_sb); + struct fuse_in_arg ext = { .size = 0, .value = NULL }; + int err = 0; + + if (fc->init_security) + err = get_security_context(dentry, mode, &ext); + + if (!err && ext.size) { + WARN_ON(args->in_numargs >= ARRAY_SIZE(args->in_args)); + args->is_ext = true; + args->ext_idx = args->in_numargs++; + args->in_args[args->ext_idx] = ext; + } else { + kfree(ext.value); + } + + return err; +} + +static void free_ext_value(struct fuse_args *args) +{ + if (args->is_ext) + kfree(args->in_args[args->ext_idx].value); +} + /* * Atomic create+open operation * @@ -541,8 +569,6 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, struct fuse_entry_out outentry; struct fuse_inode *fi; struct fuse_file *ff; - void *security_ctx = NULL; - u32 security_ctxlen; bool trunc = flags & O_TRUNC; /* Userspace expects S_IFREG in create mode */ @@ -586,19 +612,12 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, args.out_args[1].size = sizeof(outopen); args.out_args[1].value = &outopen; - if (fm->fc->init_security) { - err = get_security_context(entry, mode, &security_ctx, - &security_ctxlen); - if (err) - goto out_put_forget_req; - - args.in_numargs = 3; - args.in_args[2].size = security_ctxlen; - args.in_args[2].value = security_ctx; - } + err = get_create_ext(&args, entry, mode); + if (err) + goto out_put_forget_req; err = fuse_simple_request(fm, &args); - kfree(security_ctx); + free_ext_value(&args); if (err) goto out_free_ff; @@ -705,8 +724,6 @@ static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args, struct dentry *d; int err; struct fuse_forget_link *forget; - void *security_ctx = NULL; - u32 security_ctxlen; if (fuse_is_bad(dir)) return -EIO; @@ -721,21 +738,14 @@ static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args, args->out_args[0].size = sizeof(outarg); args->out_args[0].value = &outarg; - if (fm->fc->init_security && args->opcode != FUSE_LINK) { - err = get_security_context(entry, mode, &security_ctx, - &security_ctxlen); + if (args->opcode != FUSE_LINK) { + err = get_create_ext(args, entry, mode); if (err) goto out_put_forget_req; - - BUG_ON(args->in_numargs != 2); - - args->in_numargs = 3; - args->in_args[2].size = security_ctxlen; - args->in_args[2].value = security_ctx; } err = fuse_simple_request(fm, args); - kfree(security_ctx); + free_ext_value(args); if (err) goto out_put_forget_req; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index c673faefdcb9..ac300f14aa2d 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -249,8 +249,9 @@ struct fuse_page_desc { struct fuse_args { uint64_t nodeid; uint32_t opcode; - unsigned short in_numargs; - unsigned short out_numargs; + uint8_t in_numargs; + uint8_t out_numargs; + uint8_t ext_idx; bool force:1; bool noreply:1; bool nocreds:1; @@ -261,6 +262,7 @@ struct fuse_args { bool page_zeroing:1; bool page_replace:1; bool may_block:1; + bool is_ext:1; struct fuse_in_arg in_args[3]; struct fuse_arg out_args[2]; void (*end)(struct fuse_mount *fm, struct fuse_args *args, int error); |