2025-12-24 12:23:07
Linux
PUBLISHED
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Set end correctly when doing batch carry
Even though the test suite covers this it somehow became obscured that
this wasnt working.
The test iommufd_ioas.mock_domain.access_domain_destory would blow up
rarely.
end should be set to 1 because this just pushed an item, the carry, to the
pfns list.
Sometimes the test would blow up with:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP
CPU: 5 PID: 584 Comm: iommufd Not tainted 6.5.0-rc1-dirty #1236
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:batch_unpin+0xa2/0x100 [iommufd]
Code: 17 48 81 fe ff ff 07 00 77 70 48 8b 15 b7 be 97 e2 48 85 d2 74 14 48 8b 14 fa 48 85 d2 74 0b 40 0f b6 f6 48 c1 e6 04 48 01 f2 <48> 8b 3a 48 c1 e0 06 89 ca 48 89 de 48 83 e7 f0 48 01 c7 e8 96 dc
RSP: 0018:ffffc90001677a58 EFLAGS: 00010246
RAX: 00007f7e2646f000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000fefc4c8d RDI: 0000000000fefc4c
RBP: ffffc90001677a80 R08: 0000000000000048 R09: 0000000000000200
R10: 0000000000030b98 R11: ffffffff81f3bb40 R12: 0000000000000001
R13: ffff888101f75800 R14: ffffc90001677ad0 R15: 00000000000001fe
FS: 00007f9323679740(0000) GS:ffff8881ba540000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000105ede003 CR4: 00000000003706a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace: