In the Linux kernel, the following vulnerability has been resolved:
io_uring/sqpoll: work around a potential audit memory leak
kmemleak complains that there's a memory leak related to connect handling:
unreferenced object 0xffff0001093bdf00 (size 128): comm "iou-sqp-455", pid 457, jiffies 4294894164 hex dump (first 32 bytes): 02 00 fa ea 7f 00 00 01 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 (crc 2e481b1a): [<00000000c0a26af4>] kmemleakalloc+0x30/0x38 [<000000009c30bb45>] kmalloctrace+0x228/0x358 [<000000009da9d39f>] _auditsockaddr+0xd0/0x138 [<0000000089a93e34>] moveaddrtokernel+0x1a0/0x1f8 [<000000000b4e80e6>] ioconnectprep+0x1ec/0x2d4 [<00000000abfbcd99>] iosubmitsqes+0x588/0x1e48 [<00000000e7c25e07>] iosqthread+0x8a4/0x10e4 [<00000000d999b491>] retfrom_fork+0x10/0x20
which can can happen if:
1) The command type does something on the prep side that triggers an audit call. 2) The thread hasn't done any operations before this that triggered an audit call inside ->issue(), where we have audituringentry() and audituringexit().
Work around this by issuing a blanket NOP operation before the SQPOLL does anything.