From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Tue, 12 May 2020 17:18:27 +0000 (+0200)
Subject: 5.6-stable patches
X-Git-Tag: v4.19.123~13
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9554d31cc44d80aeb047b025c33bf36de305d9d9;p=thirdparty%2Fkernel%2Fstable-queue.git

5.6-stable patches

added patches:
	io_uring-don-t-use-fd-for-openat-openat2-statx.patch
---

diff --git a/queue-5.6/io_uring-don-t-use-fd-for-openat-openat2-statx.patch b/queue-5.6/io_uring-don-t-use-fd-for-openat-openat2-statx.patch
new file mode 100644
index 00000000000..93370d371d0
--- /dev/null
+++ b/queue-5.6/io_uring-don-t-use-fd-for-openat-openat2-statx.patch
@@ -0,0 +1,63 @@
+From 63ff822358b276137059520cf16e587e8073e80f Mon Sep 17 00:00:00 2001
+From: Max Kellermann <mk@cm4all.com>
+Date: Thu, 7 May 2020 14:56:15 -0600
+Subject: io_uring: don't use 'fd' for openat/openat2/statx
+
+From: Max Kellermann <mk@cm4all.com>
+
+Based on commit 63ff822358b276137059520cf16e587e8073e80f upstream.
+
+If an operation's flag `needs_file` is set, the function
+io_req_set_file() calls io_file_get() to obtain a `struct file*`.
+
+This fails for `O_PATH` file descriptors, because io_file_get() calls
+fget(), which rejects `O_PATH` file descriptors.  To support `O_PATH`,
+fdget_raw() must be used (like path_init() in `fs/namei.c` does).
+This rejection causes io_req_set_file() to throw `-EBADF`.  This
+breaks the operations `openat`, `openat2` and `statx`, where `O_PATH`
+file descriptors are commonly used.
+
+This could be solved by adding support for `O_PATH` file descriptors
+with another `io_op_def` flag, but since those three operations don't
+need the `struct file*` but operate directly on the numeric file
+descriptors, the best solution here is to simply remove `needs_file`
+(and the accompanying flag `fd_non_reg`).
+
+Cc: stable@vger.kernel.org
+Signed-off-by: Max Kellermann <mk@cm4all.com>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/io_uring.c |    6 ------
+ 1 file changed, 6 deletions(-)
+
+--- a/fs/io_uring.c
++++ b/fs/io_uring.c
+@@ -696,8 +696,6 @@ static const struct io_op_def io_op_defs
+ 		.needs_file		= 1,
+ 	},
+ 	[IORING_OP_OPENAT] = {
+-		.needs_file		= 1,
+-		.fd_non_neg		= 1,
+ 		.file_table		= 1,
+ 		.needs_fs		= 1,
+ 	},
+@@ -711,8 +709,6 @@ static const struct io_op_def io_op_defs
+ 	},
+ 	[IORING_OP_STATX] = {
+ 		.needs_mm		= 1,
+-		.needs_file		= 1,
+-		.fd_non_neg		= 1,
+ 		.needs_fs		= 1,
+ 		.file_table		= 1,
+ 	},
+@@ -743,8 +739,6 @@ static const struct io_op_def io_op_defs
+ 		.unbound_nonreg_file	= 1,
+ 	},
+ 	[IORING_OP_OPENAT2] = {
+-		.needs_file		= 1,
+-		.fd_non_neg		= 1,
+ 		.file_table		= 1,
+ 		.needs_fs		= 1,
+ 	},
diff --git a/queue-5.6/series b/queue-5.6/series
index 485932b4344..e4846ff0027 100644
--- a/queue-5.6/series
+++ b/queue-5.6/series
@@ -113,3 +113,4 @@ scripts-decodecode-fix-trapping-instruction-formatting.patch
 mm-memcg-fix-error-return-value-of-mem_cgroup_css_alloc.patch
 bdi-move-bdi_dev_name-out-of-line.patch
 bdi-add-a-dev_name-field-to-struct-backing_dev_info.patch
+io_uring-don-t-use-fd-for-openat-openat2-statx.patch