CVE-2024-26786

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> iommufd: Fix iopt_access_list_id overwrite bug<br /> <br /> Syzkaller reported the following WARN_ON:<br /> WARNING: CPU: 1 PID: 4738 at drivers/iommu/iommufd/io_pagetable.c:1360<br /> <br /> Call Trace:<br /> iommufd_access_change_ioas+0x2fe/0x4e0<br /> iommufd_access_destroy_object+0x50/0xb0<br /> iommufd_object_remove+0x2a3/0x490<br /> iommufd_object_destroy_user<br /> iommufd_access_destroy+0x71/0xb0<br /> iommufd_test_staccess_release+0x89/0xd0<br /> __fput+0x272/0xb50<br /> __fput_sync+0x4b/0x60<br /> __do_sys_close<br /> __se_sys_close<br /> __x64_sys_close+0x8b/0x110<br /> do_syscall_x64<br /> <br /> The mismatch between the access pointer in the list and the passed-in<br /> pointer is resulting from an overwrite of access-&gt;iopt_access_list_id, in<br /> iopt_add_access(). Called from iommufd_access_change_ioas() when<br /> xa_alloc() succeeds but iopt_calculate_iova_alignment() fails.<br /> <br /> Add a new_id in iopt_add_access() and only update iopt_access_list_id when<br /> returning successfully.