5.18-stable patches

added patches:
	io_uring-fix-not-locked-access-to-fixed-buf-table.patch

diff --git a/queue-5.18/io_uring-fix-not-locked-access-to-fixed-buf-table.patch b/queue-5.18/io_uring-fix-not-locked-access-to-fixed-buf-table.patch
new file mode 100644 (file)
index 0000000..9d6eda8
--- /dev/null
+++ b/queue-5.18/io_uring-fix-not-locked-access-to-fixed-buf-table.patch
@@ -0,0 +1,85 @@
+From 05b538c1765f8d14a71ccf5f85258dcbeaf189f7 Mon Sep 17 00:00:00 2001
+From: Pavel Begunkov <asml.silence@gmail.com>
+Date: Thu, 9 Jun 2022 08:34:35 +0100
+Subject: io_uring: fix not locked access to fixed buf table
+
+From: Pavel Begunkov <asml.silence@gmail.com>
+
+commit 05b538c1765f8d14a71ccf5f85258dcbeaf189f7 upstream.
+
+We can look inside the fixed buffer table only while holding
+->uring_lock, however in some cases we don't do the right async prep for
+IORING_OP_{WRITE,READ}_FIXED ending up with NULL req->imu forcing making
+an io-wq worker to try to resolve the fixed buffer without proper
+locking.
+
+Move req->imu setup into early req init paths, i.e. io_prep_rw(), which
+is called unconditionally for rw requests and under uring_lock.
+
+Fixes: 634d00df5e1cf ("io_uring: add full-fledged dynamic buffers support")
+Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/io_uring.c |   34 ++++++++++++++++++----------------
+ 1 file changed, 18 insertions(+), 16 deletions(-)
+
+--- a/fs/io_uring.c
++++ b/fs/io_uring.c
+@@ -3187,6 +3187,21 @@ static int io_prep_rw(struct io_kiocb *r
+       int ret;
+ 
+       kiocb->ki_pos = READ_ONCE(sqe->off);
++      /* used for fixed read/write too - just read unconditionally */
++      req->buf_index = READ_ONCE(sqe->buf_index);
++      req->imu = NULL;
++
++      if (req->opcode == IORING_OP_READ_FIXED ||
++          req->opcode == IORING_OP_WRITE_FIXED) {
++              struct io_ring_ctx *ctx = req->ctx;
++              u16 index;
++
++              if (unlikely(req->buf_index >= ctx->nr_user_bufs))
++                      return -EFAULT;
++              index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
++              req->imu = ctx->user_bufs[index];
++              io_req_set_rsrc_node(req, ctx, 0);
++      }
+ 
+       ioprio = READ_ONCE(sqe->ioprio);
+       if (ioprio) {
+@@ -3199,11 +3214,9 @@ static int io_prep_rw(struct io_kiocb *r
+               kiocb->ki_ioprio = get_current_ioprio();
+       }
+ 
+-      req->imu = NULL;
+       req->rw.addr = READ_ONCE(sqe->addr);
+       req->rw.len = READ_ONCE(sqe->len);
+       req->rw.flags = READ_ONCE(sqe->rw_flags);
+-      req->buf_index = READ_ONCE(sqe->buf_index);
+       return 0;
+ }
+ 
+@@ -3335,20 +3348,9 @@ static int __io_import_fixed(struct io_k
+ static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
+                          unsigned int issue_flags)
+ {
+-      struct io_mapped_ubuf *imu = req->imu;
+-      u16 index, buf_index = req->buf_index;
+-
+-      if (likely(!imu)) {
+-              struct io_ring_ctx *ctx = req->ctx;
+-
+-              if (unlikely(buf_index >= ctx->nr_user_bufs))
+-                      return -EFAULT;
+-              io_req_set_rsrc_node(req, ctx, issue_flags);
+-              index = array_index_nospec(buf_index, ctx->nr_user_bufs);
+-              imu = READ_ONCE(ctx->user_bufs[index]);
+-              req->imu = imu;
+-      }
+-      return __io_import_fixed(req, rw, iter, imu);
++      if (WARN_ON_ONCE(!req->imu))
++              return -EFAULT;
++      return __io_import_fixed(req, rw, iter, req->imu);
+ }
+ 
+ static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)

diff --git a/queue-5.18/series b/queue-5.18/series
index 680a72db6c69dede94ba5626c4e4b11ea5ae40e1..0c7475526ea85057ec6164d9bf95dcd0cc02b231 100644 (file)
--- a/queue-5.18/series
+++ b/queue-5.18/series
@@ -3,3 +3,4 @@ clocksource-drivers-ixp4xx-drop-boardfile-probe-path.patch
 bcache-memset-on-stack-variables-in-bch_btree_check-and-bch_sectors_dirty_init.patch
 hinic-replace-memcpy-with-direct-assignment.patch
 powerpc-ftrace-remove-ftrace-init-tramp-once-kernel-init-is-complete.patch
+io_uring-fix-not-locked-access-to-fixed-buf-table.patch