In the Linux kernel, the following vulnerability has been resolved: iommufd: Do not corrupt the pfn list when doing batch carry If batch->end is 0 then setting npfns[0] before computing the new value of pfns will fail to adjust the pfn and result in various page accounting corruptions. It should be ordered after. This seems to result in various kinds of page meta-data corruption related failures: WARNING: CPU: 1 PID: 527 at mm/gup.c:75 trygrabfolio+0x503/0x740 Modules linked in: CPU: 1 PID: 527 Comm: repro Not tainted 6.3.0-rc2-eeac8ede1755+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:trygrabfolio+0x503/0x740 Code: e3 01 48 89 de e8 6d c1 dd ff 48 85 db 0f 84 7c fe ff ff e8 4f bf dd ff 49 8d 47 ff 48 89 45 d0 e9 73 fe ff ff e8 3d bf dd ff <0f> 0b 31 db e9 d0 fc ff ff e8 2f bf dd ff 48 8b 5d c8 31 ff 48 89 RSP: 0018:ffffc90000f37908 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000000fffffc02 RCX: ffffffff81504c26 RDX: 0000000000000000 RSI: ffff88800d030000 RDI: 0000000000000002 RBP: ffffc90000f37948 R08: 000000000003ca24 R09: 0000000000000008 R10: 000000000003ca00 R11: 0000000000000023 R12: ffffea000035d540 R13: 0000000000000001 R14: 0000000000000000 R15: ffffea000035d540 FS: 00007fecbf659740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200011c3 CR3: 000000000ef66006 CR4: 0000000000770ee0 PKRU: 55555554 Call Trace: <TASK> internalgetuserpagesfast+0xd32/0x2200 pinuserpagesfast+0x65/0x90 pfnreaderuserpin+0x376/0x390 pfnreadernext+0x14a/0x7b0 pfnreaderfirst+0x140/0x1b0 ioptareafilldomain+0x74/0x210 iopttableadddomain+0x30e/0x6e0 iommufddeviceselftestattach+0x7f/0x140 iommufdtest+0x10ff/0x16f0 iommufdfopsioctl+0x206/0x330 __x64sysioctl+0x10e/0x160 dosyscall64+0x3b/0x90 entrySYSCALL64afterhwframe+0x72/0xdc