cbcvebase.
CVE-2021-46974
published 2024-02-27

CVE-2021-46974: In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
16.0th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case where the off_reg is sitting in the dst register is not correct given then we cannot just invert the add to a sub or vice versa. As a fix, perform the final bitwise and-op unconditionally into AX from the off_reg, then move the pointer from the src to dst and finally use AX as the source for the original pointer arithmetic operation such that the inversion yields a correct result. The single non-AX mov in between is possible given constant blinding is retaining it as it's not an immediate based operation.

Affected

23 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.38-1 (bookworm)linux 5.10.38-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 4.14.113 < 4.14.2334.14.233
linuxlinux>= 4.19.19 < 4.19.1904.19.190
linuxlinux>= 4.20.6 < 4.214.21
linuxlinux>= 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 < 53e0db429b37a32b8fc706d0d90eb4583ad1384853e0db429b37a32b8fc706d0d90eb4583ad13848
linuxlinux>= 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 < 2cfa537674cd1051a3b8111536d77d0558f33d5d2cfa537674cd1051a3b8111536d77d0558f33d5d
linuxlinux>= 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 < 6eba92a4d4be8feb4dc33976abac544fa99d6ecc6eba92a4d4be8feb4dc33976abac544fa99d6ecc
linuxlinux>= 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 < 7cf64d8679ca1cb20cf57d6a88bfee79a0922a667cf64d8679ca1cb20cf57d6a88bfee79a0922a66
linuxlinux>= 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 < b9b34ddbe2076ade359cd5ce7537d5ed019e9807b9b34ddbe2076ade359cd5ce7537d5ed019e9807
linuxlinux>= ae03b6b1c880a03d4771257336dc3bca156dd51b < 4d542ddb88fb2f39bf7f14caa2902f3e8d06f6ba4d542ddb88fb2f39bf7f14caa2902f3e8d06f6ba
linuxlinux>= f92a819b4cbef8c9527d9797110544b2055a4b96 < 0e2dfdc74a7f4036127356d42ea59388f153f42c0e2dfdc74a7f4036127356d42ea59388f153f42c
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 4.14.113 < 4.14.2334.14.233
linuxlinux_kernel>= 4.19.19 < 4.19.1904.19.190
linuxlinux_kernel>= 5.0 < 5.4.1175.4.117
linuxlinux_kernel>= 5.11 < 5.11.195.11.19
linuxlinux_kernel>= 5.12 < 5.12.25.12.2
linuxlinux_kernel>= 5.5 < 5.10.355.10.35

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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