Puranjay Mohan e63985ecd2 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		2024-03-06 15:18:16 -08:00
..
boot	RISC-V Devicetree fixes for v6.8-rc6	2024-02-23 13:54:07 +01:00
configs	Merge patch series "RISC-V SBI debug console extension support"	2024-01-11 07:36:27 -08:00
errata	Merge patch series "riscv: errata: thead: use riscv_nonstd_cache_ops for CMO"	2024-01-11 07:36:30 -08:00
include	bpf, riscv64/cfi: Support kCFI + BPF on riscv64	2024-03-06 15:18:16 -08:00
kernel	bpf, riscv64/cfi: Support kCFI + BPF on riscv64	2024-03-06 15:18:16 -08:00
kvm	KVM/riscv fixes for 6.8, take #1	2024-02-14 12:35:40 -05:00
lib	work around gcc bugs with 'asm goto' with outputs	2024-02-09 15:57:48 -08:00
mm	riscv: Fix arch_tlbbatch_flush() by clearing the batch cpumask	2024-02-07 10:19:37 -08:00
net	bpf, riscv64/cfi: Support kCFI + BPF on riscv64	2024-03-06 15:18:16 -08:00
purgatory	riscv: Use SYM_*() assembly macros instead of deprecated ones	2023-11-06 09:42:47 -08:00
tools	riscv: Check relocations at compile time	2023-04-19 07:46:32 -07:00
Kbuild	kexec: rename ARCH_HAS_KEXEC_PURGATORY	2023-08-18 10:18:54 -07:00
Kconfig	RISC-V Patches for the 6.8 Merge Window, Part 4	2024-01-20 11:06:04 -08:00
Kconfig.debug	riscv: Add tests for riscv module loading	2023-11-07 14:59:32 -08:00
Kconfig.errata	RISC-V Patches for the 6.8 Merge Window, Part 4	2024-01-20 11:06:04 -08:00
Kconfig.socs	SoC driver updates for 6.7	2023-11-01 14:46:51 -10:00
Makefile	riscv: add dependency among Image(.gz), loader(.bin), and vmlinuz.efi	2024-01-17 18:18:20 -08:00
Makefile.postlink	kbuild: remove ARCH_POSTLINK from module builds	2023-10-28 21:10:08 +09:00