Description: incorrect computation of branch  displacements in BPF JIT compiler
References:
 https://www.openwall.com/lists/oss-security/2021/04/08/1
Notes:
Bugs:
upstream: released (5.12-rc7) [e4d4d456436bfb2fe412ee2cd489f7658449b098, 26f55a59dc65ff77cd1c4b37991e26497fc68049]
5.10-upstream-stable: released (5.10.29) [3edb8967d91ecbc4c5eee34a65d4124267327574, faa30969f66e74910e9424214a4a426c2dc249d8]
4.19-upstream-stable: released (4.19.186) [5f26f1f838aa960045c712e13dbab8ff451fed74, 7b77ae2a0d6f9e110e13e85d802124b111b3e027]
4.9-upstream-stable: released (4.9.266) [d4b234e44aa7108aeadc7b84b162c6f882597005]
sid: released (5.10.28-1) [bugfix/x86/0001-bpf-x86-Validate-computation-of-branch-displacements.patch, bugfix/x86/0002-bpf-x86-Validate-computation-of-branch-displacements.patch]
4.19-buster-security: released (4.19.194-1)
4.9-stretch-security: released (4.9.272-1)