In the Linux kernel, the following vulnerability has been resolved:
bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG
When BPF_TRAMP_F_CALL_ORIG is set, the trampoline calls __bpf_tramp_enter() and __bpf_tramp_exit() functions, passing them the struct bpf_tramp_image *im pointer as an argument in R0.
The trampoline generation code uses emit_addr_mov_i64() to emit instructions for moving the bpf_tramp_image address into R0, but emit_addr_mov_i64() assumes the address to be in the vmalloc() space and uses only 48 bits. Because bpf_tramp_image is allocated using kzalloc(), its address can use more than 48-bits, in this case the trampoline will pass an invalid address to __bpf_tramp_enter/exit() causing a kernel crash.
Fix this by using emit_a64_mov_i64() in place of emit_addr_mov_i64() as it can work with addresses that are greater than 48-bits.
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H5.5/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H