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Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r--kernel/trace/bpf_trace.c190
1 files changed, 146 insertions, 44 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 1ed08967fb97..e8da032bb6fc 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -6,6 +6,7 @@
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/bpf.h>
+#include <linux/bpf_verifier.h>
#include <linux/bpf_perf_event.h>
#include <linux/btf.h>
#include <linux/filter.h>
@@ -368,8 +369,6 @@ static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
return &bpf_probe_write_user_proto;
}
-static DEFINE_RAW_SPINLOCK(trace_printk_lock);
-
#define MAX_TRACE_PRINTK_VARARGS 3
#define BPF_TRACE_PRINTK_SIZE 1024
@@ -377,23 +376,22 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
u64, arg2, u64, arg3)
{
u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
- u32 *bin_args;
- static char buf[BPF_TRACE_PRINTK_SIZE];
- unsigned long flags;
+ struct bpf_bprintf_data data = {
+ .get_bin_args = true,
+ .get_buf = true,
+ };
int ret;
- ret = bpf_bprintf_prepare(fmt, fmt_size, args, &bin_args,
- MAX_TRACE_PRINTK_VARARGS);
+ ret = bpf_bprintf_prepare(fmt, fmt_size, args,
+ MAX_TRACE_PRINTK_VARARGS, &data);
if (ret < 0)
return ret;
- raw_spin_lock_irqsave(&trace_printk_lock, flags);
- ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
+ ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
- trace_bpf_trace_printk(buf);
- raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
+ trace_bpf_trace_printk(data.buf);
- bpf_bprintf_cleanup();
+ bpf_bprintf_cleanup(&data);
return ret;
}
@@ -426,30 +424,29 @@ const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
return &bpf_trace_printk_proto;
}
-BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, data,
+BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, args,
u32, data_len)
{
- static char buf[BPF_TRACE_PRINTK_SIZE];
- unsigned long flags;
+ struct bpf_bprintf_data data = {
+ .get_bin_args = true,
+ .get_buf = true,
+ };
int ret, num_args;
- u32 *bin_args;
if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
- (data_len && !data))
+ (data_len && !args))
return -EINVAL;
num_args = data_len / 8;
- ret = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
+ ret = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
if (ret < 0)
return ret;
- raw_spin_lock_irqsave(&trace_printk_lock, flags);
- ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
+ ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
- trace_bpf_trace_printk(buf);
- raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
+ trace_bpf_trace_printk(data.buf);
- bpf_bprintf_cleanup();
+ bpf_bprintf_cleanup(&data);
return ret;
}
@@ -471,23 +468,25 @@ const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
}
BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
- const void *, data, u32, data_len)
+ const void *, args, u32, data_len)
{
+ struct bpf_bprintf_data data = {
+ .get_bin_args = true,
+ };
int err, num_args;
- u32 *bin_args;
if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
- (data_len && !data))
+ (data_len && !args))
return -EINVAL;
num_args = data_len / 8;
- err = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
+ err = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
if (err < 0)
return err;
- seq_bprintf(m, fmt, bin_args);
+ seq_bprintf(m, fmt, data.bin_args);
- bpf_bprintf_cleanup();
+ bpf_bprintf_cleanup(&data);
return seq_has_overflowed(m) ? -EOVERFLOW : 0;
}
@@ -686,8 +685,7 @@ BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
}
perf_sample_data_init(sd, 0, 0);
- sd->raw = &raw;
- sd->sample_flags |= PERF_SAMPLE_RAW;
+ perf_sample_save_raw_data(sd, &raw);
err = __bpf_perf_event_output(regs, map, flags, sd);
@@ -745,8 +743,7 @@ u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
perf_fetch_caller_regs(regs);
perf_sample_data_init(sd, 0, 0);
- sd->raw = &raw;
- sd->sample_flags |= PERF_SAMPLE_RAW;
+ perf_sample_save_raw_data(sd, &raw);
ret = __bpf_perf_event_output(regs, map, flags, sd);
out:
@@ -773,7 +770,7 @@ BPF_CALL_0(bpf_get_current_task_btf)
const struct bpf_func_proto bpf_get_current_task_btf_proto = {
.func = bpf_get_current_task_btf,
.gpl_only = true,
- .ret_type = RET_PTR_TO_BTF_ID,
+ .ret_type = RET_PTR_TO_BTF_ID_TRUSTED,
.ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
};
@@ -832,6 +829,7 @@ static void do_bpf_send_signal(struct irq_work *entry)
work = container_of(entry, struct send_signal_irq_work, irq_work);
group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
+ put_task_struct(work->task);
}
static int bpf_send_signal_common(u32 sig, enum pid_type type)
@@ -847,6 +845,9 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
return -EPERM;
if (unlikely(!nmi_uaccess_okay()))
return -EPERM;
+ /* Task should not be pid=1 to avoid kernel panic. */
+ if (unlikely(is_global_init(current)))
+ return -EPERM;
if (irqs_disabled()) {
/* Do an early check on signal validity. Otherwise,
@@ -863,7 +864,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
* to the irq_work. The current task may change when queued
* irq works get executed.
*/
- work->task = current;
+ work->task = get_task_struct(current);
work->sig = sig;
work->type = type;
irq_work_queue(&work->irq_work);
@@ -1234,7 +1235,7 @@ __diag_ignore_all("-Wmissing-prototypes",
* Return: a bpf_key pointer with a valid key pointer if the key is found, a
* NULL pointer otherwise.
*/
-struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
+__bpf_kfunc struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
{
key_ref_t key_ref;
struct bpf_key *bkey;
@@ -1283,7 +1284,7 @@ struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
* Return: a bpf_key pointer with an invalid key pointer set from the
* pre-determined ID on success, a NULL pointer otherwise
*/
-struct bpf_key *bpf_lookup_system_key(u64 id)
+__bpf_kfunc struct bpf_key *bpf_lookup_system_key(u64 id)
{
struct bpf_key *bkey;
@@ -1307,7 +1308,7 @@ struct bpf_key *bpf_lookup_system_key(u64 id)
* Decrement the reference count of the key inside *bkey*, if the pointer
* is valid, and free *bkey*.
*/
-void bpf_key_put(struct bpf_key *bkey)
+__bpf_kfunc void bpf_key_put(struct bpf_key *bkey)
{
if (bkey->has_ref)
key_put(bkey->key);
@@ -1327,7 +1328,7 @@ void bpf_key_put(struct bpf_key *bkey)
*
* Return: 0 on success, a negative value on error.
*/
-int bpf_verify_pkcs7_signature(struct bpf_dynptr_kern *data_ptr,
+__bpf_kfunc int bpf_verify_pkcs7_signature(struct bpf_dynptr_kern *data_ptr,
struct bpf_dynptr_kern *sig_ptr,
struct bpf_key *trusted_keyring)
{
@@ -1456,6 +1457,10 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_get_current_cgroup_id_proto;
case BPF_FUNC_get_current_ancestor_cgroup_id:
return &bpf_get_current_ancestor_cgroup_id_proto;
+ case BPF_FUNC_cgrp_storage_get:
+ return &bpf_cgrp_storage_get_proto;
+ case BPF_FUNC_cgrp_storage_delete:
+ return &bpf_cgrp_storage_delete_proto;
#endif
case BPF_FUNC_send_signal:
return &bpf_send_signal_proto;
@@ -1480,9 +1485,9 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
case BPF_FUNC_get_task_stack:
return &bpf_get_task_stack_proto;
case BPF_FUNC_copy_from_user:
- return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
+ return &bpf_copy_from_user_proto;
case BPF_FUNC_copy_from_user_task:
- return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL;
+ return &bpf_copy_from_user_task_proto;
case BPF_FUNC_snprintf_btf:
return &bpf_snprintf_btf_proto;
case BPF_FUNC_per_cpu_ptr:
@@ -1490,8 +1495,12 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
case BPF_FUNC_this_cpu_ptr:
return &bpf_this_cpu_ptr_proto;
case BPF_FUNC_task_storage_get:
+ if (bpf_prog_check_recur(prog))
+ return &bpf_task_storage_get_recur_proto;
return &bpf_task_storage_get_proto;
case BPF_FUNC_task_storage_delete:
+ if (bpf_prog_check_recur(prog))
+ return &bpf_task_storage_delete_recur_proto;
return &bpf_task_storage_delete_proto;
case BPF_FUNC_for_each_map_elem:
return &bpf_for_each_map_elem_proto;
@@ -2452,6 +2461,8 @@ struct bpf_kprobe_multi_link {
unsigned long *addrs;
u64 *cookies;
u32 cnt;
+ u32 mods_cnt;
+ struct module **mods;
};
struct bpf_kprobe_multi_run_ctx {
@@ -2507,6 +2518,14 @@ error:
return err;
}
+static void kprobe_multi_put_modules(struct module **mods, u32 cnt)
+{
+ u32 i;
+
+ for (i = 0; i < cnt; i++)
+ module_put(mods[i]);
+}
+
static void free_user_syms(struct user_syms *us)
{
kvfree(us->syms);
@@ -2519,6 +2538,7 @@ static void bpf_kprobe_multi_link_release(struct bpf_link *link)
kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
unregister_fprobe(&kmulti_link->fp);
+ kprobe_multi_put_modules(kmulti_link->mods, kmulti_link->mods_cnt);
}
static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
@@ -2528,6 +2548,7 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
kvfree(kmulti_link->addrs);
kvfree(kmulti_link->cookies);
+ kfree(kmulti_link->mods);
kfree(kmulti_link);
}
@@ -2550,7 +2571,7 @@ static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void
swap(*cookie_a, *cookie_b);
}
-static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b)
+static int bpf_kprobe_multi_addrs_cmp(const void *a, const void *b)
{
const unsigned long *addr_a = a, *addr_b = b;
@@ -2561,7 +2582,7 @@ static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b)
static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
{
- return __bpf_kprobe_multi_cookie_cmp(a, b);
+ return bpf_kprobe_multi_addrs_cmp(a, b);
}
static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
@@ -2579,7 +2600,7 @@ static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
return 0;
entry_ip = run_ctx->entry_ip;
addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
- __bpf_kprobe_multi_cookie_cmp);
+ bpf_kprobe_multi_addrs_cmp);
if (!addr)
return 0;
cookie = link->cookies + (addr - link->addrs);
@@ -2663,6 +2684,79 @@ static void symbols_swap_r(void *a, void *b, int size, const void *priv)
}
}
+struct modules_array {
+ struct module **mods;
+ int mods_cnt;
+ int mods_cap;
+};
+
+static int add_module(struct modules_array *arr, struct module *mod)
+{
+ struct module **mods;
+
+ if (arr->mods_cnt == arr->mods_cap) {
+ arr->mods_cap = max(16, arr->mods_cap * 3 / 2);
+ mods = krealloc_array(arr->mods, arr->mods_cap, sizeof(*mods), GFP_KERNEL);
+ if (!mods)
+ return -ENOMEM;
+ arr->mods = mods;
+ }
+
+ arr->mods[arr->mods_cnt] = mod;
+ arr->mods_cnt++;
+ return 0;
+}
+
+static bool has_module(struct modules_array *arr, struct module *mod)
+{
+ int i;
+
+ for (i = arr->mods_cnt - 1; i >= 0; i--) {
+ if (arr->mods[i] == mod)
+ return true;
+ }
+ return false;
+}
+
+static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u32 addrs_cnt)
+{
+ struct modules_array arr = {};
+ u32 i, err = 0;
+
+ for (i = 0; i < addrs_cnt; i++) {
+ struct module *mod;
+
+ preempt_disable();
+ mod = __module_address(addrs[i]);
+ /* Either no module or we it's already stored */
+ if (!mod || has_module(&arr, mod)) {
+ preempt_enable();
+ continue;
+ }
+ if (!try_module_get(mod))
+ err = -EINVAL;
+ preempt_enable();
+ if (err)
+ break;
+ err = add_module(&arr, mod);
+ if (err) {
+ module_put(mod);
+ break;
+ }
+ }
+
+ /* We return either err < 0 in case of error, ... */
+ if (err) {
+ kprobe_multi_put_modules(arr.mods, arr.mods_cnt);
+ kfree(arr.mods);
+ return err;
+ }
+
+ /* or number of modules found if everything is ok. */
+ *mods = arr.mods;
+ return arr.mods_cnt;
+}
+
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
struct bpf_kprobe_multi_link *link = NULL;
@@ -2775,8 +2869,16 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
link);
}
+ err = get_modules_for_addrs(&link->mods, addrs, cnt);
+ if (err < 0) {
+ bpf_link_cleanup(&link_primer);
+ return err;
+ }
+ link->mods_cnt = err;
+
err = register_fprobe_ips(&link->fp, addrs, cnt);
if (err) {
+ kprobe_multi_put_modules(link->mods, link->mods_cnt);
bpf_link_cleanup(&link_primer);
return err;
}