diff mbox series

[bpf-next,v3,2/3] bpf: Report internal error on incorrect ld_imm64 in check_ld_imm()

Message ID 20231011-jmp-into-reserved-fields-v3-2-97d2aa979788@gmail.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series bpf: Detect jumping to reserved code of ld_imm64 | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
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bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for x86_64 with gcc
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bpf/vmtest-bpf-next-VM_Test-4 success Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-7 success Logs for test_maps on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-5 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-13 success Logs for test_progs on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-1 success Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-6 success Logs for test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for test_maps on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-8 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for test_progs on aarch64 with gcc
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bpf/vmtest-bpf-next-VM_Test-19 success Logs for test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for test_progs_no_alu32_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-21 success Logs for test_progs_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-22 success Logs for test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-28 success Logs for veristat
bpf/vmtest-bpf-next-VM_Test-24 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-25 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-27 success Logs for test_verifier on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-23 success Logs for test_progs_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-18 success Logs for test_progs_no_alu32_parallel on aarch64 with gcc
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1352 this patch: 1352
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 1364 this patch: 1364
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1375 this patch: 1375
netdev/checkpatch warning WARNING: line length of 87 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Hao Sun Oct. 11, 2023, 9 a.m. UTC 
The verifier currently reports "invalid BPF_LD_IMM64 insn" if the size
of ld_imm64 is not BPF_DW. The log is not accurate, bacause we already
have bpf_code_in_insntable() check in resolve_pseudo_idimm64(), which
guarantees the validity of insn code. If the verifier meets an invalid
ld_imm64 in check_ld_imm(), then somewhere else in the verifier must be
wrong. In such case, current log is confusing and does not reflect the
right thing. Therefore, make the verifier report internal error.

Signed-off-by: Hao Sun <sunhao.th@gmail.com>
---
 kernel/bpf/verifier.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 725ac0b464cf..d25838a2c430 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -14532,8 +14532,8 @@  static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
 	int err;
 
 	if (BPF_SIZE(insn->code) != BPF_DW) {
-		verbose(env, "invalid BPF_LD_IMM insn\n");
-		return -EINVAL;
+		verbose(env, "verifier internal error: ld_imm64 size is not BPF_DW\n");
+		return -EFAULT;
 	}
 	if (insn->off != 0) {
 		verbose(env, "BPF_LD_IMM64 uses reserved fields\n");