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

Daniel Borkmann says:

====================
pull-request: bpf 2018-06-08

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix in the BPF verifier to reject modified ctx pointers on helper
   functions, from Daniel.

2) Fix in BPF kselftests for get_cgroup_id_user() helper to only
   record the cgroup id for a provided pid in order to reduce test
   failures from processes interferring with the test, from Yonghong.

3) Fix a crash in AF_XDP's mem accounting when the process owning
   the sock has CAP_IPC_LOCK capabilities set, from Daniel.

4) Fix an issue for AF_XDP on 32 bit machines where XDP_UMEM_PGOFF_*_RING
   defines need ULL suffixes and use loff_t type as they are otherwise
   truncated, from Geert.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller
2018-06-07 20:06:25 -04:00
7 changed files with 118 additions and 26 deletions

View File

@@ -11,12 +11,24 @@ struct bpf_map_def SEC("maps") cg_ids = {
.max_entries = 1,
};
struct bpf_map_def SEC("maps") pidmap = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(__u32),
.value_size = sizeof(__u32),
.max_entries = 1,
};
SEC("tracepoint/syscalls/sys_enter_nanosleep")
int trace(void *ctx)
{
__u32 key = 0;
__u32 pid = bpf_get_current_pid_tgid();
__u32 key = 0, *expected_pid;
__u64 *val;
expected_pid = bpf_map_lookup_elem(&pidmap, &key);
if (!expected_pid || *expected_pid != pid)
return 0;
val = bpf_map_lookup_elem(&cg_ids, &key);
if (val)
*val = bpf_get_current_cgroup_id();

View File

@@ -50,13 +50,13 @@ int main(int argc, char **argv)
const char *probe_name = "syscalls/sys_enter_nanosleep";
const char *file = "get_cgroup_id_kern.o";
int err, bytes, efd, prog_fd, pmu_fd;
int cgroup_fd, cgidmap_fd, pidmap_fd;
struct perf_event_attr attr = {};
int cgroup_fd, cgidmap_fd;
struct bpf_object *obj;
__u64 kcgid = 0, ucgid;
__u32 key = 0, pid;
int exit_code = 1;
char buf[256];
__u32 key = 0;
err = setup_cgroup_environment();
if (CHECK(err, "setup_cgroup_environment", "err %d errno %d\n", err,
@@ -81,6 +81,14 @@ int main(int argc, char **argv)
cgidmap_fd, errno))
goto close_prog;
pidmap_fd = bpf_find_map(__func__, obj, "pidmap");
if (CHECK(pidmap_fd < 0, "bpf_find_map", "err %d errno %d\n",
pidmap_fd, errno))
goto close_prog;
pid = getpid();
bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
snprintf(buf, sizeof(buf),
"/sys/kernel/debug/tracing/events/%s/id", probe_name);
efd = open(buf, O_RDONLY, 0);

View File

@@ -8647,7 +8647,7 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
.errstr = "dereference of modified ctx ptr R1 off=68+8, ctx+const is allowed, ctx+const+const is not",
.errstr = "dereference of modified ctx ptr",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
@@ -12258,6 +12258,62 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
.retval = 5,
},
{
"pass unmodified ctx pointer to helper",
.insns = {
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
},
{
"pass modified ctx pointer to helper, 1",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
.errstr = "dereference of modified ctx ptr",
},
{
"pass modified ctx pointer to helper, 2",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_socket_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result_unpriv = REJECT,
.result = REJECT,
.errstr_unpriv = "dereference of modified ctx ptr",
.errstr = "dereference of modified ctx ptr",
},
{
"pass modified ctx pointer to helper, 3",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, 0),
BPF_ALU64_IMM(BPF_AND, BPF_REG_3, 4),
BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
.errstr = "variable ctx access var_off=(0x0; 0x4)",
},
};
static int probe_filter_length(const struct bpf_insn *fp)