{"id":"DEBIAN-CVE-2024-26906","details":"In the Linux kernel, the following vulnerability has been resolved:  x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()  When trying to use copy_from_kernel_nofault() to read vsyscall page through a bpf program, the following oops was reported:    BUG: unable to handle page fault for address: ffffffffff600000   #PF: supervisor read access in kernel mode   #PF: error_code(0x0000) - not-present page   PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0   Oops: 0000 [#1] PREEMPT SMP PTI   CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......   RIP: 0010:copy_from_kernel_nofault+0x6f/0x110   ......   Call Trace:    \u003cTASK\u003e    ? copy_from_kernel_nofault+0x6f/0x110    bpf_probe_read_kernel+0x1d/0x50    bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d    trace_call_bpf+0xc5/0x1c0    perf_call_bpf_enter.isra.0+0x69/0xb0    perf_syscall_enter+0x13e/0x200    syscall_trace_enter+0x188/0x1c0    do_syscall_64+0xb5/0xe0    entry_SYSCALL_64_after_hwframe+0x6e/0x76    \u003c/TASK\u003e   ......   ---[ end trace 0000000000000000 ]---  The oops is triggered when:  1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall page and invokes copy_from_kernel_nofault() which in turn calls __get_user_asm().  2) Because the vsyscall page address is not readable from kernel space, a page fault exception is triggered accordingly.  3) handle_page_fault() considers the vsyscall page address as a user space address instead of a kernel space address. This results in the fix-up setup by bpf not being applied and a page_fault_oops() is invoked due to SMAP.  Considering handle_page_fault() has already considered the vsyscall page address as a userspace address, fix the problem by disallowing vsyscall page read for copy_from_kernel_nofault().","modified":"2026-09-15T09:02:55.924026629Z","published":"2024-04-17T11:15:11.207Z","upstream":["CVE-2024-26906"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-26906"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.85-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26906.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.7.12-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26906.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.7.12-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26906.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}