linux-stable.git/io_uring, branch v6.0.7

io_uring: don't gate task_work run on TIF_NOTIFY_SIGNAL

2022-10-29T08:08:35+00:00

[ Upstream commit 46a525e199e4037516f7e498c18f065b09df32ac ]

This isn't a reliable mechanism to tell if we have task_work pending, we
really should be looking at whether we have any items queued. This is
problematic if forward progress is gated on running said task_work. One
such example is reading from a pipe, where the write side has been closed
right before the read is started. The fput() of the file queues TWA_RESUME
task_work, and we need that task_work to be run before ->release() is
called for the pipe. If ->release() isn't called, then the read will sit
forever waiting on data that will never arise.

Fix this by io_run_task_work() so it checks if we have task_work pending
rather than rely on TIF_NOTIFY_SIGNAL for that. The latter obviously
doesn't work for task_work that is queued without TWA_SIGNAL.

Reported-by: Christiano Haesbaert 
Cc: stable@vger.kernel.org
Link: https://github.com/axboe/liburing/issues/665
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd()

2022-10-29T08:08:35+00:00

[ Upstream commit 16bbdfe5fb0e78e0acb13e45fc127e9a296913f2 ]

Syzkaller produced the below call trace:

 BUG: KASAN: null-ptr-deref in io_msg_ring+0x3cb/0x9f0
 Write of size 8 at addr 0000000000000070 by task repro/16399

 CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7
 Call Trace:
  
  dump_stack_lvl+0xcd/0x134
  ? io_msg_ring+0x3cb/0x9f0
  kasan_report+0xbc/0xf0
  ? io_msg_ring+0x3cb/0x9f0
  kasan_check_range+0x140/0x190
  io_msg_ring+0x3cb/0x9f0
  ? io_msg_ring_prep+0x300/0x300
  io_issue_sqe+0x698/0xca0
  io_submit_sqes+0x92f/0x1c30
  __do_sys_io_uring_enter+0xae4/0x24b0
....
 RIP: 0033:0x7f2eaf8f8289
 RSP: 002b:00007fff40939718 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2eaf8f8289
 RDX: 0000000000000000 RSI: 0000000000006f71 RDI: 0000000000000004
 RBP: 00007fff409397a0 R08: 0000000000000000 R09: 0000000000000039
 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004006d0
 R13: 00007fff40939880 R14: 0000000000000000 R15: 0000000000000000
  
 Kernel panic - not syncing: panic_on_warn set ...

We don't have a NULL check on file_ptr in io_msg_send_fd() function,
so when file_ptr is NUL src_file is also NULL and get_file()
dereferences a NULL pointer and leads to above crash.

Add a NULL check to fix this issue.

Fixes: e6130eba8a84 ("io_uring: add support for passing fixed file descriptors")
Reported-by: syzkaller 
Signed-off-by: Harshit Mogalapalli 
Link: https://lore.kernel.org/r/20221019171218.1337614-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

io_uring/rw: remove leftover debug statement

2022-10-29T08:08:33+00:00

[ Upstream commit 5c61795ea97c170347c5c4af0c159bd877b8af71 ]

This debug statement was never meant to go into the upstream release,
kill it off before it ends up in a release. It was just part of the
testing for the initial version of the patch.

Fixes: 2ec33a6c3cca ("io_uring/rw: ensure kiocb_end_write() is always called")
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

io-wq: Fix memory leak in worker creation

2022-10-26T10:22:57+00:00

commit 996d3efeb091c503afd3ee6b5e20eabf446fd955 upstream.

If the CPU mask allocation for a node fails, then the memory allocated for
the 'io_wqe' struct of the current node doesn't get freed on the error
handling path, since it has not yet been added to the 'wqes' array.

This was spotted when fuzzing v6.1-rc1 with Syzkaller:
BUG: memory leak
unreferenced object 0xffff8880093d5000 (size 1024):
  comm "syz-executor.2", pid 7701, jiffies 4295048595 (age 13.900s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000cb463369>] __kmem_cache_alloc_node+0x18e/0x720
    [<00000000147a3f9c>] kmalloc_node_trace+0x2a/0x130
    [<000000004e107011>] io_wq_create+0x7b9/0xdc0
    [<00000000c38b2018>] io_uring_alloc_task_context+0x31e/0x59d
    [<00000000867399da>] __io_uring_add_tctx_node.cold+0x19/0x1ba
    [<000000007e0e7a79>] io_uring_setup.cold+0x1b80/0x1dce
    [<00000000b545e9f6>] __x64_sys_io_uring_setup+0x5d/0x80
    [<000000008a8a7508>] do_syscall_64+0x5d/0x90
    [<000000004ac08bec>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 0e03496d1967 ("io-wq: use private CPU mask")
Cc: stable@vger.kernel.org
Signed-off-by: Rafael Mendonca 
Link: https://lore.kernel.org/r/20221020014710.902201-1-rafaelmendsr@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring/net: fail zc send when unsupported by socket

2022-10-26T10:22:55+00:00

commit edf81438799ccead7122948446d7e44b083e788d upstream.

If a protocol doesn't support zerocopy it will silently fall back to
copying. This type of behaviour has always been a source of troubles
so it's better to fail such requests instead.

Cc:  # 6.0
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/2db3c7f16bb6efab4b04569cd16e6242b40c5cb3.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring/rw: ensure kiocb_end_write() is always called

2022-10-21T10:39:29+00:00

commit 2ec33a6c3cca9fe2465e82050c81f5ffdc508b36 upstream.

A previous commit moved the notifications and end-write handling, but
it is now missing a few spots where we also want to call both of those.
Without that, we can potentially be missing file notifications, and
more importantly, have an imbalance in the super_block writers sem
accounting.

Fixes: b000145e9907 ("io_uring/rw: defer fsnotify calls to task context")
Reported-by: Dave Chinner 
Link: https://lore.kernel.org/all/20221010050319.GC2703033@dread.disaster.area/
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring: fix fdinfo sqe offsets calculation

2022-10-21T10:39:29+00:00

commit 00927931cb630bbf8edb6d7f4dadb25139fc5e16 upstream.

Only with the big sqe feature they take 128 bytes per entry, but we
unconditionally advance by 128B. Fix it by using sq_shift.

Fixes: 3b8fdd1dc35e3 ("io_uring/fdinfo: fix sqe dumping for IORING_SETUP_SQE128")
Reported-and-tested-by: syzbot+e5198737e8a2d23d958c@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/8b41287cb75d5efb8fcb5cccde845ddbbadd8372.1665449983.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring/net: fix notif cqe reordering

2022-10-21T10:39:27+00:00

[ upstream commit 108893ddcc4d3aa0a4a02aeb02d478e997001227 ]

send zc is not restricted to !IO_URING_F_UNLOCKED anymore and so
we can't use task-tw ordering trick to order notification cqes
with requests completions. In this case leave it alone and let
io_send_zc_cleanup() flush it.

Cc: stable@vger.kernel.org
Fixes: 53bdc88aac9a2 ("io_uring/notif: order notif vs send CQEs")
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/0031f3a00d492e814a4a0935a2029a46d9c9ba06.1664486545.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring/net: don't skip notifs for failed requests

2022-10-21T10:39:27+00:00

[ upstream commit 6ae91ac9a6aa7d6005c3c6d0f4d263fbab9f377f ]

We currently only add a notification CQE when the send succeded, i.e.
cqe.res >= 0. However, it'd be more robust to do buffer notifications
for failed requests as well in case drivers decide do something fanky.

Always return a buffer notification after initial prep, don't hide it.
This behaviour is better aligned with documentation and the patch also
helps the userspace to respect it.

Cc: stable@vger.kernel.org # 6.0
Suggested-by: Stefan Metzmacher 
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/9c8bead87b2b980fcec441b8faef52188b4a6588.1664292100.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

io_uring/net: rename io_sendzc()

2022-10-21T10:39:27+00:00

[ upstream commit b0e9b5517eb12fa80c72e205fe28534c2e2f39b9 ]

Simple renaming of io_sendzc*() functions in preparatio to adding
a zerocopy sendmsg variant.

Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/265af46829e6076dd220011b1858dc3151969226.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman