Jens Axboe 939007d2a9 io_uring/sqpoll: retain test for whether the CPU is valid ... commit a09c17240b upstream. A recent commit ensured that SQPOLL cannot be setup with a CPU that isn't in the current tasks cpuset, but it also dropped testing whether the CPU is valid in the first place. Without that, if a task passes in a CPU value that is too high, the following KASAN splat can get triggered: BUG: KASAN: stack-out-of-bounds in io_sq_offload_create+0x858/0xaa4 Read of size 8 at addr ffff800089bc7b90 by task wq-aff.t/1391 CPU: 4 UID: 1000 PID: 1391 Comm: wq-aff.t Not tainted 6.11.0-rc7-00227-g371c468f4db6 #7080 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace.part.0+0xcc/0xe0 show_stack+0x14/0x1c dump_stack_lvl+0x58/0x74 print_report+0x16c/0x4c8 kasan_report+0x9c/0xe4 __asan_report_load8_noabort+0x1c/0x24 io_sq_offload_create+0x858/0xaa4 io_uring_setup+0x1394/0x17c4 __arm64_sys_io_uring_setup+0x6c/0x180 invoke_syscall+0x6c/0x260 el0_svc_common.constprop.0+0x158/0x224 do_el0_svc+0x3c/0x5c el0_svc+0x34/0x70 el0t_64_sync_handler+0x118/0x124 el0t_64_sync+0x168/0x16c The buggy address belongs to stack of task wq-aff.t/1391 and is located at offset 48 in frame: io_sq_offload_create+0x0/0xaa4 This frame has 1 object: [32, 40) 'allowed_mask' The buggy address belongs to the virtual mapping at [ffff800089bc0000, ffff800089bc9000) created by: kernel_clone+0x124/0x7e0 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000d740af80 pfn:0x11740a memcg:ffff0000c2706f02 flags: 0xbffe00000000000(node=0|zone=2|lastcpupid=0x1fff) raw: 0bffe00000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff0000d740af80 0000000000000000 00000001ffffffff ffff0000c2706f02 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff800089bc7a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff800089bc7b00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 >ffff800089bc7b80: 00 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff800089bc7c00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 ffff800089bc7c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f3 Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202409161632.cbeeca0d-lkp@intel.com Fixes: f011c9cf04 ("io_uring/sqpoll: do not allow pinning outside of cpuset") Tested-by: Felix Moessbauer <felix.moessbauer@siemens.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2024-10-22 15:40:42 +02:00
..
io_uring.c	io_uring/sqpoll: retain test for whether the CPU is valid	2024-10-22 15:40:42 +02:00
io-wq.c	io_uring/io-wq: limit retrying worker initialisation	2024-08-19 05:45:22 +02:00
io-wq.h	io_uring: break out of iowq iopoll on teardown	2023-09-19 12:22:54 +02:00
Makefile	io_uring: move to separate directory	2022-12-14 11:37:31 +01:00