Description

In the Linux kernel, the following vulnerability has been resolved: io-wq: Fix memory leak in worker creation 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: [] __kmem_cache_alloc_node+0x18e/0x720 [] kmalloc_node_trace+0x2a/0x130 [] io_wq_create+0x7b9/0xdc0 [] io_uring_alloc_task_context+0x31e/0x59d [] __io_uring_add_tctx_node.cold+0x19/0x1ba [] io_uring_setup.cold+0x1b80/0x1dce [] __x64_sys_io_uring_setup+0x5d/0x80 [] do_syscall_64+0x5d/0x90 [] entry_SYSCALL_64_after_hwframe+0x63/0xcd