Smatch warning: io_fixup_rw_res() warn:
unsigned 'res' is never less than zero.
Change type of 'res' from unsigned to long.
Fixes: d6b7efc722 ("io_uring/rw: fix error'ed retry return values")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12521a5d5c upstream.
Jiffy to ktime CQ waiting conversion broke how we treat timeouts, in
particular we rearm it anew every time we get into
io_cqring_wait_schedule() without adjusting the timeout. Waiting for 2
CQEs and getting a task_work in the middle may double the timeout value,
or even worse in some cases task may wait indefinitely.
Cc: stable@vger.kernel.org
Fixes: 228339662b ("io_uring: don't convert to jiffies for waiting on timeouts")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f7bffddd71b08f28a877d44d37ac953ddb01590d.1672915663.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 343190841a ]
We only check the register opcode value inside the restricted ring
section, move it into the main io_uring_register() function instead
and check it up front.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 998b30c394 ]
Syzkaller reports a NULL deref bug as follows:
BUG: KASAN: null-ptr-deref in io_tctx_exit_cb+0x53/0xd3
Read of size 4 at addr 0000000000000138 by task file1/1955
CPU: 1 PID: 1955 Comm: file1 Not tainted 6.1.0-rc7-00103-gef4d3ea40565 #75
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0xcd/0x134
? io_tctx_exit_cb+0x53/0xd3
kasan_report+0xbb/0x1f0
? io_tctx_exit_cb+0x53/0xd3
kasan_check_range+0x140/0x190
io_tctx_exit_cb+0x53/0xd3
task_work_run+0x164/0x250
? task_work_cancel+0x30/0x30
get_signal+0x1c3/0x2440
? lock_downgrade+0x6e0/0x6e0
? lock_downgrade+0x6e0/0x6e0
? exit_signals+0x8b0/0x8b0
? do_raw_read_unlock+0x3b/0x70
? do_raw_spin_unlock+0x50/0x230
arch_do_signal_or_restart+0x82/0x2470
? kmem_cache_free+0x260/0x4b0
? putname+0xfe/0x140
? get_sigframe_size+0x10/0x10
? do_execveat_common.isra.0+0x226/0x710
? lockdep_hardirqs_on+0x79/0x100
? putname+0xfe/0x140
? do_execveat_common.isra.0+0x238/0x710
exit_to_user_mode_prepare+0x15f/0x250
syscall_exit_to_user_mode+0x19/0x50
do_syscall_64+0x42/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0023:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 002b:00000000fffb7790 EFLAGS: 00000200 ORIG_RAX: 000000000000000b
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Kernel panic - not syncing: panic_on_warn set ...
This happens because the adding of task_work from io_ring_exit_work()
isn't synchronized with canceling all work items from eg exec. The
execution of the two are ordered in that they are both run by the task
itself, but if io_tctx_exit_cb() is queued while we're canceling all
work items off exec AND gets executed when the task exits to userspace
rather than in the main loop in io_uring_cancel_generic(), then we can
find current->io_uring == NULL and hit the above crash.
It's safe to add this NULL check here, because the execution of the two
paths are done by the task itself.
Cc: stable@vger.kernel.org
Fixes: d56d938b4b ("io_uring: do ctx initiated file note removal")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20221206093833.3812138-1-harshit.m.mogalapalli@oracle.com
[axboe: add code comment and also put an explanation in the commit msg]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ed29b0b4fd ]
In preparation for splitting io_uring up a bit, move it into its own
top level directory. It didn't really belong in fs/ anyway, as it's
not a file system only API.
This adds io_uring/ and moves the core files in there, and updates the
MAINTAINERS file for the new location.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 998b30c394 ("io_uring: Fix a null-ptr-deref in io_tctx_exit_cb()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
