IORING_OP_SYMLINKAT behaves like symlinkat(2) and takes the same flags and arguments. Suggested-by: Christian Brauner <christian.brauner@xxxxxxxxxx> Link: https://lore.kernel.org/io-uring/20210514145259.wtl4xcsp52woi6ab@wittgenstein/ Signed-off-by: Dmitry Kadashev <dkadashev@xxxxxxxxx> Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx> --- fs/internal.h | 1 + fs/io_uring.c | 66 +++++++++++++++++++++++++++++++++++ fs/namei.c | 3 +- include/uapi/linux/io_uring.h | 1 + 4 files changed, 69 insertions(+), 2 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 207a455e32d3..3b3954214385 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -78,6 +78,7 @@ int may_linkat(struct user_namespace *mnt_userns, struct path *link); int do_renameat2(int olddfd, struct filename *oldname, int newdfd, struct filename *newname, unsigned int flags); int do_mkdirat(int dfd, struct filename *name, umode_t mode); +int do_symlinkat(struct filename *from, int newdfd, struct filename *to); /* * namespace.c diff --git a/fs/io_uring.c b/fs/io_uring.c index 7aa08ed78452..c161f06a3cea 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -680,6 +680,13 @@ struct io_mkdir { struct filename *filename; }; +struct io_symlink { + struct file *file; + int new_dfd; + struct filename *oldpath; + struct filename *newpath; +}; + struct io_completion { struct file *file; struct list_head list; @@ -833,6 +840,7 @@ struct io_kiocb { struct io_rename rename; struct io_unlink unlink; struct io_mkdir mkdir; + struct io_symlink symlink; /* use only after cleaning per-op data, see io_clean_op() */ struct io_completion compl; }; @@ -1048,6 +1056,7 @@ static const struct io_op_def io_op_defs[] = { [IORING_OP_RENAMEAT] = {}, [IORING_OP_UNLINKAT] = {}, [IORING_OP_MKDIRAT] = {}, + [IORING_OP_SYMLINKAT] = {}, }; static bool io_disarm_next(struct io_kiocb *req); @@ -3599,6 +3608,54 @@ static int io_mkdirat(struct io_kiocb *req, int issue_flags) return 0; } +static int io_symlinkat_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + struct io_symlink *sl = &req->symlink; + const char __user *oldpath, *newpath; + + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index) + return -EINVAL; + if (unlikely(req->flags & REQ_F_FIXED_FILE)) + return -EBADF; + + sl->new_dfd = READ_ONCE(sqe->fd); + oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr)); + newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2)); + + sl->oldpath = getname(oldpath); + if (IS_ERR(sl->oldpath)) + return PTR_ERR(sl->oldpath); + + sl->newpath = getname(newpath); + if (IS_ERR(sl->newpath)) { + putname(sl->oldpath); + return PTR_ERR(sl->newpath); + } + + req->flags |= REQ_F_NEED_CLEANUP; + return 0; +} + +static int io_symlinkat(struct io_kiocb *req, int issue_flags) +{ + struct io_symlink *sl = &req->symlink; + int ret; + + if (issue_flags & IO_URING_F_NONBLOCK) + return -EAGAIN; + + ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath); + + req->flags &= ~REQ_F_NEED_CLEANUP; + if (ret < 0) + req_set_fail(req); + io_req_complete(req, ret); + return 0; +} + static int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { @@ -6009,6 +6066,8 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return io_unlinkat_prep(req, sqe); case IORING_OP_MKDIRAT: return io_mkdirat_prep(req, sqe); + case IORING_OP_SYMLINKAT: + return io_symlinkat_prep(req, sqe); } printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", @@ -6173,6 +6232,10 @@ static void io_clean_op(struct io_kiocb *req) case IORING_OP_MKDIRAT: putname(req->mkdir.filename); break; + case IORING_OP_SYMLINKAT: + putname(req->symlink.oldpath); + putname(req->symlink.newpath); + break; } } if ((req->flags & REQ_F_POLLED) && req->apoll) { @@ -6304,6 +6367,9 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) case IORING_OP_MKDIRAT: ret = io_mkdirat(req, issue_flags); break; + case IORING_OP_SYMLINKAT: + ret = io_symlinkat(req, issue_flags); + break; default: ret = -EINVAL; break; diff --git a/fs/namei.c b/fs/namei.c index f99de6e294ad..f5b0379d2f8c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4208,8 +4208,7 @@ int vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir, } EXPORT_SYMBOL(vfs_symlink); -static int do_symlinkat(struct filename *from, int newdfd, - struct filename *to) +int do_symlinkat(struct filename *from, int newdfd, struct filename *to) { int error; struct dentry *dentry; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 49a24a149eeb..796f37ab4ce3 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -138,6 +138,7 @@ enum { IORING_OP_RENAMEAT, IORING_OP_UNLINKAT, IORING_OP_MKDIRAT, + IORING_OP_SYMLINKAT, /* this goes last, obviously */ IORING_OP_LAST, -- 2.30.2
