CVE-2021-47292

In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix memleak in io_init_wq_offload() I got memory leak report when
doing fuzz test: BUG: memory leak unreferenced object 0xffff888107310a80
(size 96): comm “syz-executor.6”, pid 4610, jiffies 4295140240 (age
20.135s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 … 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00
…N… backtrace: [<000000001974933b>] kmalloc
include/linux/slab.h:591 [inline] [<000000001974933b>] kzalloc
include/linux/slab.h:721 [inline] [<000000001974933b>] io_init_wq_offload
fs/io_uring.c:7920 [inline] [<000000001974933b>]
io_uring_alloc_task_context+0x466/0x640 fs/io_uring.c:7955
[<0000000039d0800d>] __io_uring_add_tctx_node+0x256/0x360
fs/io_uring.c:9016 [<000000008482e78c>] io_uring_add_tctx_node
fs/io_uring.c:9052 [inline] [<000000008482e78c>] __do_sys_io_uring_enter
fs/io_uring.c:9354 [inline] [<000000008482e78c>] __se_sys_io_uring_enter
fs/io_uring.c:9301 [inline] [<000000008482e78c>]
__x64_sys_io_uring_enter+0xabc/0xc20 fs/io_uring.c:9301
[<00000000b875f18f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<00000000b875f18f>] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
[<000000006b0a8484>] entry_SYSCALL_64_after_hwframe+0x44/0xae CPU0 CPU1
io_uring_enter io_uring_enter io_uring_add_tctx_node io_uring_add_tctx_node
__io_uring_add_tctx_node __io_uring_add_tctx_node
io_uring_alloc_task_context io_uring_alloc_task_context io_init_wq_offload
io_init_wq_offload hash = kzalloc hash = kzalloc ctx->hash_map = hash
ctx->hash_map = hash <- one of the hash is leaked When calling
io_uring_enter() in parallel, the ‘hash_map’ will be leaked, add uring_lock
to protect ‘hash_map’.