diff options
| author | Jens Axboe <axboe@kernel.dk> | 2023-11-27 16:47:04 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-11-28 07:56:16 -0700 |
| commit | c392cbecd8eca4c53f2bf508731257d9d0a21c2d (patch) | |
| tree | 74054d568c3324dc69b65b037d9076466c2352af /io_uring/io_uring.c | |
| parent | edecf1689768452ba1a64b7aaf3a47a817da651a (diff) | |
io_uring/kbuf: defer release of mapped buffer rings
If a provided buffer ring is setup with IOU_PBUF_RING_MMAP, then the
kernel allocates the memory for it and the application is expected to
mmap(2) this memory. However, io_uring uses remap_pfn_range() for this
operation, so we cannot rely on normal munmap/release on freeing them
for us.
Stash an io_buf_free entry away for each of these, if any, and provide
a helper to free them post ->release().
Cc: stable@vger.kernel.org
Fixes: c56e022c0a27 ("io_uring: add support for user mapped provided buffer ring")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/io_uring.c')
| -rw-r--r-- | io_uring/io_uring.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index e40b11438210..3a216f0744dd 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -325,6 +325,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) INIT_LIST_HEAD(&ctx->sqd_list); INIT_LIST_HEAD(&ctx->cq_overflow_list); INIT_LIST_HEAD(&ctx->io_buffers_cache); + INIT_HLIST_HEAD(&ctx->io_buf_list); io_alloc_cache_init(&ctx->rsrc_node_cache, IO_NODE_ALLOC_CACHE_MAX, sizeof(struct io_rsrc_node)); io_alloc_cache_init(&ctx->apoll_cache, IO_ALLOC_CACHE_MAX, @@ -2950,6 +2951,7 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) ctx->mm_account = NULL; } io_rings_free(ctx); + io_kbuf_mmap_list_free(ctx); percpu_ref_exit(&ctx->refs); free_uid(ctx->user); |