kernel.git/arch/s390/net, branch linux-5.4.y

bpf, s390: Fix potential memory leak about jit_data

2021-10-13T08:08:20Z

[ Upstream commit 686cb8b9f6b46787f035afe8fbd132a74e6b1bdd ] Make sure to free jit_data through kfree() in the error path. Fixes: 1c8f9b91c456 ("bpf: s390: add JIT support for multi-function programs") Signed-off-by: Tiezhu Yang Acked-by: Ilya Leoshkevich Reviewed-by: Christian Borntraeger Signed-off-by: Christian Borntraeger Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/bpf: Fix 64-bit subtraction of the -0x80000000 constant

2021-09-22T10:26:46Z

commit 6e61dc9da0b7a0d91d57c2e20b5ea4fd2d4e7e53 upstream. The JIT uses agfi for subtracting constants, but -(-0x80000000) cannot be represented as a 32-bit signed binary integer. Fix by using algfi in this particular case. Reported-by: Johan Almbladh Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Reviewed-by: Heiko Carstens Signed-off-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

s390/bpf: Fix optimizing out zero-extensions

2021-09-22T10:26:46Z

commit db7bee653859ef7179be933e7d1384644f795f26 upstream. Currently the JIT completely removes things like `reg32 += 0`, however, the BPF_ALU semantics requires the target register to be zero-extended in such cases. Fix by optimizing out only the arithmetic operation, but not the subsequent zero-extension. Reported-by: Johan Almbladh Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Reviewed-by: Heiko Carstens Signed-off-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

bpf: Introduce BPF nospec instruction for mitigating Spectre v4

2021-09-15T07:47:38Z

commit f5e81d1117501546b7be050c5fbafa6efd2c722c upstream. In case of JITs, each of the JIT backends compiles the BPF nospec instruction /either/ to a machine instruction which emits a speculation barrier /or/ to /no/ machine instruction in case the underlying architecture is not affected by Speculative Store Bypass or has different mitigations in place already. This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence' instruction for mitigation. In case of arm64, we rely on the firmware mitigation as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled, it works for all of the kernel code with no need to provide any additional instructions here (hence only comment in arm64 JIT). Other archs can follow as needed. The BPF nospec instruction is specifically targeting Spectre v4 since i) we don't use a serialization barrier for the Spectre v1 case, and ii) mitigation instructions for v1 and v4 might be different on some archs. The BPF nospec is required for a future commit, where the BPF verifier does annotate intermediate BPF programs with speculation barriers. Co-developed-by: Piotr Krysiuk Co-developed-by: Benedict Schlueter Signed-off-by: Daniel Borkmann Signed-off-by: Piotr Krysiuk Signed-off-by: Benedict Schlueter Acked-by: Alexei Starovoitov Signed-off-by: Sasha Levin [OP: - adjusted context for 5.4 - apply riscv changes to /arch/riscv/net/bpf_jit_comp.c] Signed-off-by: Ovidiu Panait Signed-off-by: Greg Kroah-Hartman

s390/bpf: Perform r1 range checking before accessing jit->seen_reg[r1]

2021-07-28T11:30:55Z

[ Upstream commit 91091656252f5d6d8c476e0c92776ce9fae7b445 ] Currently array jit->seen_reg[r1] is being accessed before the range checking of index r1. The range changing on r1 should be performed first since it will avoid any potential out-of-range accesses on the array seen_reg[] and also it is more optimal to perform checks on r1 before fetching data from the array. Fix this by swapping the order of the checks before the array access. Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Signed-off-by: Colin Ian King Signed-off-by: Daniel Borkmann Tested-by: Ilya Leoshkevich Acked-by: Ilya Leoshkevich Link: https://lore.kernel.org/bpf/20210715125712.24690-1-colin.king@canonical.com Signed-off-by: Sasha Levin

s390/bpf: Use kvcalloc for addrs array

2019-12-31T15:45:06Z

[ Upstream commit 166f11d11f6f70439830d09bfa5552ec1b368494 ] A BPF program may consist of 1m instructions, which means JIT instruction-address mapping can be as large as 4m. s390 has FORCE_MAX_ZONEORDER=9 (for memory hotplug reasons), which means maximum kmalloc size is 1m. This makes it impossible to JIT programs with more than 256k instructions. Fix by using kvcalloc, which falls back to vmalloc for larger allocations. An alternative would be to use a radix tree, but that is not supported by bpf_prog_fill_jited_linfo. Signed-off-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20191107141838.92202-1-iii@linux.ibm.com Signed-off-by: Sasha Levin

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2019-09-06T14:49:17Z

Daniel Borkmann says: ==================== The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add the ability to use unaligned chunks in the AF_XDP umem. By relaxing where the chunks can be placed, it allows to use an arbitrary buffer size and place whenever there is a free address in the umem. Helps more seamless DPDK AF_XDP driver integration. Support for i40e, ixgbe and mlx5e, from Kevin and Maxim. 2) Addition of a wakeup flag for AF_XDP tx and fill rings so the application can wake up the kernel for rx/tx processing which avoids busy-spinning of the latter, useful when app and driver is located on the same core. Support for i40e, ixgbe and mlx5e, from Magnus and Maxim. 3) bpftool fixes for printf()-like functions so compiler can actually enforce checks, bpftool build system improvements for custom output directories, and addition of 'bpftool map freeze' command, from Quentin. 4) Support attaching/detaching XDP programs from 'bpftool net' command, from Daniel. 5) Automatic xskmap cleanup when AF_XDP socket is released, and several barrier/{read,write}_once fixes in AF_XDP code, from Björn. 6) Relicense of bpf_helpers.h/bpf_endian.h for future libbpf inclusion as well as libbpf versioning improvements, from Andrii. 7) Several new BPF kselftests for verifier precision tracking, from Alexei. 8) Several BPF kselftest fixes wrt endianess to run on s390x, from Ilya. 9) And more BPF kselftest improvements all over the place, from Stanislav. 10) Add simple BPF map op cache for nfp driver to batch dumps, from Jakub. 11) AF_XDP socket umem mapping improvements for 32bit archs, from Ivan. 12) Add BPF-to-BPF call and BTF line info support for s390x JIT, from Yauheni. 13) Small optimization in arm64 JIT to spare 1 insns for BPF_MOD, from Jerin. 14) Fix an error check in bpf_tcp_gen_syncookie() helper, from Petar. 15) Various minor fixes and cleanups, from Nathan, Masahiro, Masanari, Peter, Wei, Yue. ==================== Signed-off-by: David S. Miller

bpf: s390: add JIT support for bpf line info

2019-09-03T13:32:56Z

This adds support for generating bpf line info for JITed programs like commit 6f20c71d8505 ("bpf: powerpc64: add JIT support for bpf line info") does for powerpc, but it should pass the array starting from 1. This fixes test_btf. Signed-off-by: Yauheni Kaliuta Acked-by: Ilya Leoshkevich Tested-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann

bpf: s390: add JIT support for multi-function programs

2019-08-30T22:35:50Z

This adds support for bpf-to-bpf function calls in the s390 JIT compiler. The JIT compiler converts the bpf call instructions to native branch instructions. After a round of the usual passes, the start addresses of the JITed images for the callee functions are known. Finally, to fixup the branch target addresses, we need to perform an extra pass. Because of the address range in which JITed images are allocated on s390, the offsets of the start addresses of these images from __bpf_call_base are as large as 64 bits. So, for a function call, the imm field of the instruction cannot be used to determine the callee's address. Use bpf_jit_get_func_addr() helper instead. The patch borrows a lot from: commit 8c11ea5ce13d ("bpf, arm64: fix getting subprog addr from aux for calls") commit e2c95a61656d ("bpf, ppc64: generalize fetching subprog into bpf_jit_get_func_addr") commit 8484ce8306f9 ("bpf: powerpc64: add JIT support for multi-function programs") (including the commit message). test_verifier (5.3-rc6 with CONFIG_BPF_JIT_ALWAYS_ON=y): without patch: Summary: 1501 PASSED, 0 SKIPPED, 47 FAILED with patch: Summary: 1540 PASSED, 0 SKIPPED, 8 FAILED Signed-off-by: Yauheni Kaliuta Acked-by: Ilya Leoshkevich Tested-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann

s390/bpf: use 32-bit index for tail calls

2019-08-13T14:07:13Z

"p runtime/jit: pass > 32bit index to tail_call" fails when bpf_jit_enable=1, because the tail call is not executed. This in turn is because the generated code assumes index is 64-bit, while it must be 32-bit, and as a result prog array bounds check fails, while it should pass. Even if bounds check would have passed, the code that follows uses 64-bit index to compute prog array offset. Fix by using clrj instead of clgrj for comparing index with array size, and also by using llgfr for truncating index to 32 bits before using it to compute prog array offset. Fixes: 6651ee070b31 ("s390/bpf: implement bpf_tail_call() helper") Reported-by: Yauheni Kaliuta Acked-by: Vasily Gorbik Signed-off-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann