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| author | Eugene Syromiatnikov <esyr@redhat.com> | 2020-01-15 17:35:38 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-01-20 17:00:44 -0700 |
| commit | 1292e972fff2b2d81e139e0c2fe5f50249e78c58 (patch) | |
| tree | 2722e386ae97640e2584f6f58b8032bf5b54d0c8 | |
| parent | 44d282796f81eb1debc1d7cb53245b4cb3214cb5 (diff) | |
| download | linux-1292e972fff2b2d81e139e0c2fe5f50249e78c58.tar.gz linux-1292e972fff2b2d81e139e0c2fe5f50249e78c58.tar.bz2 linux-1292e972fff2b2d81e139e0c2fe5f50249e78c58.zip | |
io_uring: fix compat for IORING_REGISTER_FILES_UPDATE
fds field of struct io_uring_files_update is problematic with regards
to compat user space, as pointer size is different in 32-bit, 32-on-64-bit,
and 64-bit user space. In order to avoid custom handling of compat in
the syscall implementation, make fds __u64 and use u64_to_user_ptr in
order to retrieve it. Also, align the field naturally and check that
no garbage is passed there.
Fixes: c3a31e605620c279 ("io_uring: add support for IORING_REGISTER_FILES_UPDATE")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | fs/io_uring.c | 4 | ||||
| -rw-r--r-- | include/uapi/linux/io_uring.h | 3 |
2 files changed, 5 insertions, 2 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 187dd94fd6b1..5953d7f13690 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4463,13 +4463,15 @@ static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg, return -EINVAL; if (copy_from_user(&up, arg, sizeof(up))) return -EFAULT; + if (up.resv) + return -EINVAL; if (check_add_overflow(up.offset, nr_args, &done)) return -EOVERFLOW; if (done > ctx->nr_user_files) return -EINVAL; done = 0; - fds = (__s32 __user *) up.fds; + fds = u64_to_user_ptr(up.fds); while (nr_args) { struct fixed_file_table *table; unsigned index; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index a3300e1b9a01..55cfcb71606d 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -178,7 +178,8 @@ struct io_uring_params { struct io_uring_files_update { __u32 offset; - __s32 *fds; + __u32 resv; + __aligned_u64 /* __s32 * */ fds; }; #endif |