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| author | Pavel Begunkov <asml.silence@gmail.com> | 2023-12-06 13:26:47 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-12-07 10:35:19 -0700 |
| commit | 705318a99a138c29a512a72c3e0043b3cd7f55f4 (patch) | |
| tree | 444eddc451943aaed9443fd81c1f8c13150110e0 | |
| parent | 9865346b7e8374b57f1c3ccacdc77846c6352ff4 (diff) | |
| download | linux-stable-705318a99a138c29a512a72c3e0043b3cd7f55f4.tar.gz linux-stable-705318a99a138c29a512a72c3e0043b3cd7f55f4.tar.bz2 linux-stable-705318a99a138c29a512a72c3e0043b3cd7f55f4.zip | |
io_uring/af_unix: disable sending io_uring over sockets
File reference cycles have caused lots of problems for io_uring
in the past, and it still doesn't work exactly right and races with
unix_stream_read_generic(). The safest fix would be to completely
disallow sending io_uring files via sockets via SCM_RIGHT, so there
are no possible cycles invloving registered files and thus rendering
SCM accounting on the io_uring side unnecessary.
Cc: <stable@vger.kernel.org>
Fixes: 0091bfc81741b ("io_uring/af_unix: defer registered files gc to io_uring release")
Reported-and-suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c716c88321939156909cfa1bd8b0faaf1c804103.1701868795.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | io_uring/rsrc.h | 7 | ||||
| -rw-r--r-- | net/core/scm.c | 6 |
2 files changed, 6 insertions, 7 deletions
diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 8625181fb87a..08ac0d8e07ef 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -77,17 +77,10 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file); -#if defined(CONFIG_UNIX) -static inline bool io_file_need_scm(struct file *filp) -{ - return !!unix_get_socket(filp); -} -#else static inline bool io_file_need_scm(struct file *filp) { return false; } -#endif static inline int io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) diff --git a/net/core/scm.c b/net/core/scm.c index 880027ecf516..7dc47c17d863 100644 --- a/net/core/scm.c +++ b/net/core/scm.c @@ -26,6 +26,7 @@ #include <linux/nsproxy.h> #include <linux/slab.h> #include <linux/errqueue.h> +#include <linux/io_uring.h> #include <linux/uaccess.h> @@ -103,6 +104,11 @@ static int scm_fp_copy(struct cmsghdr *cmsg, struct scm_fp_list **fplp) if (fd < 0 || !(file = fget_raw(fd))) return -EBADF; + /* don't allow io_uring files */ + if (io_uring_get_socket(file)) { + fput(file); + return -EINVAL; + } *fpp++ = file; fpl->count++; } |