cbcvebase.
CVE-2024-56678
published 2024-12-28

CVE-2024-56678: In the Linux kernel, the following vulnerability has been resolved: powerpc/mm/fault: Fix kfence page fault reporting copy_from_kernel_nofault() can be called…

PriorityP336high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.22%
13.2th percentile
In the Linux kernel, the following vulnerability has been resolved: powerpc/mm/fault: Fix kfence page fault reporting copy_from_kernel_nofault() can be called when doing read of /proc/kcore. /proc/kcore can have some unmapped kfence objects which when read via copy_from_kernel_nofault() can cause page faults. Since *_nofault() functions define their own fixup table for handling fault, use that instead of asking kfence to handle such faults. Hence we search the exception tables for the nip which generated the fault. If there is an entry then we let the fixup table handler handle the page fault by returning an error from within ___do_page_fault(). This can be easily triggered if someone tries to do dd from /proc/kcore. eg. dd if=/proc/kcore of=/dev/null bs=1M Some example false negatives: BUG: KFENCE: invalid read in copy_from_kernel_nofault+0x9c/0x1a0 Invalid read at 0xc0000000fdff0000: copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec BUG: KFENCE: use-after-free read in copy_from_kernel_nofault+0x9c/0x1a0 Use-after-free read at 0xc0000000fe050000 (in kfence-#2): copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
debianlinux-6.1< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
linuxlinux
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < e0a470b5733c1fe068d5c58b0bb91ad539604bc6e0a470b5733c1fe068d5c58b0bb91ad539604bc6
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < 4d2655754e94741b159aa807b72ea85518a65fd54d2655754e94741b159aa807b72ea85518a65fd5
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < 9ea8d8bf9b625e8ad3be6b0432aecdc5499141219ea8d8bf9b625e8ad3be6b0432aecdc549914121
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < 7eaeb7a49b6d16640f9f3c9074c05175d74c710b7eaeb7a49b6d16640f9f3c9074c05175d74c710b
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < 15f78d2c3d1452645bd8b9da909b0ca266f83c4315f78d2c3d1452645bd8b9da909b0ca266f83c43
linuxlinux>= 90cbac0e995dd92f7bcf82f74aa50250bf194a4a < 06dbbb4d5f7126b6307ab807cbf04ecfc459b93306dbbb4d5f7126b6307ab807cbf04ecfc459b933
linuxlinux_kernel>= 0 < 6.1.123-16.1.123-1
linuxlinux_kernel>= 0 < 6.12.3-16.12.3-1
linuxlinux_kernel>= 0 < 6.12.3-16.12.3-1
linuxlinux_kernel>= 0 < 5.15.0-135.1465.15.0-135.146
linuxlinux_kernel>= 0 < 6.8.0-58.606.8.0-58.60
linuxlinux_kernel>= 0 < 6.11.0-18.186.11.0-18.18
linuxlinux_kernel>= 5.13 < 5.15.1745.15.174
linuxlinux_kernel>= 5.16 < 6.1.1206.1.120
linuxlinux_kernel>= 6.12 < 6.12.26.12.2
linuxlinux_kernel>= 6.2 < 6.6.646.6.64
linuxlinux_kernel>= 6.7 < 6.11.116.11.11

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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