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| author | Puranjay Mohan <puranjay12@gmail.com> | 2024-03-03 17:02:07 +0000 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2024-03-06 15:18:16 -0800 |
| commit | e63985ecd22681c7f5975f2e8637187a326b6791 (patch) | |
| tree | acb127a58be4cbad6faf591ede9e9aa00573d4bf /tools/lib/api/fs/tracing_path.c | |
| parent | 516fca5a7516cde7a9968f84179ed20ffb438885 (diff) | |
bpf, riscv64/cfi: Support kCFI + BPF on riscv64
The riscv BPF JIT doesn't emit proper kCFI prologues for BPF programs
and struct_ops trampolines when CONFIG_CFI_CLANG is enabled.
This causes CFI failures when calling BPF programs and can even crash
the kernel due to invalid memory accesses.
Example crash:
root@rv-selftester:~/bpf# ./test_progs -a dummy_st_ops
Unable to handle kernel paging request at virtual address ffffffff78204ffc
Oops [#1]
Modules linked in: bpf_testmod(OE) [....]
CPU: 3 PID: 356 Comm: test_progs Tainted: P OE 6.8.0-rc1 #1
Hardware name: riscv-virtio,qemu (DT)
epc : bpf_struct_ops_test_run+0x28c/0x5fc
ra : bpf_struct_ops_test_run+0x26c/0x5fc
epc : ffffffff82958010 ra : ffffffff82957ff0 sp : ff200000007abc80
gp : ffffffff868d6218 tp : ff6000008d87b840 t0 : 000000000000000f
t1 : 0000000000000000 t2 : 000000002005793e s0 : ff200000007abcf0
s1 : ff6000008a90fee0 a0 : 0000000000000000 a1 : 0000000000000000
a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000
a5 : ffffffff868dba26 a6 : 0000000000000001 a7 : 0000000052464e43
s2 : 00007ffffc0a95f0 s3 : ff6000008a90fe80 s4 : ff60000084c24c00
s5 : ffffffff78205000 s6 : ff60000088750648 s7 : ff20000000035008
s8 : fffffffffffffff4 s9 : ffffffff86200610 s10: 0000000000000000
s11: 0000000000000000 t3 : ffffffff8483dc30 t4 : ffffffff8483dc10
t5 : ffffffff8483dbf0 t6 : ffffffff8483dbd0
status: 0000000200000120 badaddr: ffffffff78204ffc cause: 000000000000000d
[<ffffffff82958010>] bpf_struct_ops_test_run+0x28c/0x5fc
[<ffffffff805083ee>] bpf_prog_test_run+0x170/0x548
[<ffffffff805029c8>] __sys_bpf+0x2d2/0x378
[<ffffffff804ff570>] __riscv_sys_bpf+0x5c/0x120
[<ffffffff8000e8fe>] syscall_handler+0x62/0xe4
[<ffffffff83362df6>] do_trap_ecall_u+0xc6/0x27c
[<ffffffff833822c4>] ret_from_exception+0x0/0x64
Code: b603 0109 b683 0189 b703 0209 8493 0609 157d 8d65 (a303) ffca
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Fatal exception
SMP: stopping secondary CPUs
Implement proper kCFI prologues for the BPF programs and callbacks and
drop __nocfi for riscv64. Fix the trampoline generation code to emit kCFI
prologue when a struct_ops trampoline is being prepared.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20240303170207.82201-2-puranjay12@gmail.com
Diffstat (limited to 'tools/lib/api/fs/tracing_path.c')
0 files changed, 0 insertions, 0 deletions