#include <bpf/bpf_helpers.h>
#include <linux/limits.h>
+#define PERF_ALIGN(x, a) __PERF_ALIGN_MASK(x, (typeof(x))(a)-1)
+#define __PERF_ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))
+
/**
* is_power_of_2() - check if a value is a power of two
* @n: the value to check
long ret;
};
-struct augmented_arg {
- unsigned int size;
- int err;
- char value[PATH_MAX];
-};
-
-struct pids_filtered {
- __uint(type, BPF_MAP_TYPE_HASH);
- __type(key, pid_t);
- __type(value, bool);
- __uint(max_entries, 64);
-} pids_filtered SEC(".maps");
-
/*
* Desired design of maximum size and alignment (see RFC2553)
*/
};
};
-struct augmented_args_payload {
- struct syscall_enter_args args;
- union {
- struct {
- struct augmented_arg arg, arg2;
- };
+struct augmented_arg {
+ unsigned int size;
+ int err;
+ union {
+ char value[PATH_MAX];
struct sockaddr_storage saddr;
- char __data[sizeof(struct augmented_arg)];
};
};
+struct pids_filtered {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __type(key, pid_t);
+ __type(value, bool);
+ __uint(max_entries, 64);
+} pids_filtered SEC(".maps");
+
+struct augmented_args_payload {
+ struct syscall_enter_args args;
+ struct augmented_arg arg, arg2; // We have to reserve space for two arguments (rename, etc)
+};
+
// We need more tmp space than the BPF stack can give us
struct augmented_args_tmp {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
struct augmented_args_payload *augmented_args = augmented_args_payload();
const void *sockaddr_arg = (const void *)args->args[1];
unsigned int socklen = args->args[2];
- unsigned int len = sizeof(augmented_args->args);
+ unsigned int len = sizeof(u64) + sizeof(augmented_args->args); // the size + err in all 'augmented_arg' structs
if (augmented_args == NULL)
return 1; /* Failure: don't filter */
- _Static_assert(is_power_of_2(sizeof(augmented_args->saddr)), "sizeof(augmented_args->saddr) needs to be a power of two");
- socklen &= sizeof(augmented_args->saddr) - 1;
+ _Static_assert(is_power_of_2(sizeof(augmented_args->arg.saddr)), "sizeof(augmented_args->arg.saddr) needs to be a power of two");
+ socklen &= sizeof(augmented_args->arg.saddr) - 1;
- bpf_probe_read_user(&augmented_args->saddr, socklen, sockaddr_arg);
+ bpf_probe_read_user(&augmented_args->arg.saddr, socklen, sockaddr_arg);
+ augmented_args->arg.size = socklen;
+ augmented_args->arg.err = 0;
return augmented__output(args, augmented_args, len + socklen);
}
struct augmented_args_payload *augmented_args = augmented_args_payload();
const void *sockaddr_arg = (const void *)args->args[4];
unsigned int socklen = args->args[5];
- unsigned int len = sizeof(augmented_args->args);
+ unsigned int len = sizeof(u64) + sizeof(augmented_args->args); // the size + err in all 'augmented_arg' structs
if (augmented_args == NULL)
return 1; /* Failure: don't filter */
- socklen &= sizeof(augmented_args->saddr) - 1;
+ socklen &= sizeof(augmented_args->arg.saddr) - 1;
- bpf_probe_read_user(&augmented_args->saddr, socklen, sockaddr_arg);
+ bpf_probe_read_user(&augmented_args->arg.saddr, socklen, sockaddr_arg);
return augmented__output(args, augmented_args, len + socklen);
}
struct augmented_args_payload *augmented_args = augmented_args_payload();
const void *oldpath_arg = (const void *)args->args[0],
*newpath_arg = (const void *)args->args[1];
- unsigned int len = sizeof(augmented_args->args), oldpath_len;
+ unsigned int len = sizeof(augmented_args->args), oldpath_len, newpath_len;
if (augmented_args == NULL)
return 1; /* Failure: don't filter */
+ len += 2 * sizeof(u64); // The overhead of size and err, just before the payload...
+
oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value));
- len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value));
+ augmented_args->arg.size = PERF_ALIGN(oldpath_len + 1, sizeof(u64));
+ len += augmented_args->arg.size;
+
+ struct augmented_arg *arg2 = (void *)&augmented_args->arg.value + augmented_args->arg.size;
+
+ newpath_len = augmented_arg__read_str(arg2, newpath_arg, sizeof(augmented_args->arg.value));
+ arg2->size = newpath_len;
+
+ len += newpath_len;
return augmented__output(args, augmented_args, len);
}
struct augmented_args_payload *augmented_args = augmented_args_payload();
const void *oldpath_arg = (const void *)args->args[1],
*newpath_arg = (const void *)args->args[3];
- unsigned int len = sizeof(augmented_args->args), oldpath_len;
+ unsigned int len = sizeof(augmented_args->args), oldpath_len, newpath_len;
if (augmented_args == NULL)
return 1; /* Failure: don't filter */
+ len += 2 * sizeof(u64); // The overhead of size and err, just before the payload...
+
oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value));
- len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value));
+ augmented_args->arg.size = PERF_ALIGN(oldpath_len + 1, sizeof(u64));
+ len += augmented_args->arg.size;
+
+ struct augmented_arg *arg2 = (void *)&augmented_args->arg.value + augmented_args->arg.size;
+
+ newpath_len = augmented_arg__read_str(arg2, newpath_arg, sizeof(augmented_args->arg.value));
+ arg2->size = newpath_len;
+
+ len += newpath_len;
return augmented__output(args, augmented_args, len);
}
{
struct augmented_args_payload *augmented_args = augmented_args_payload();
const struct perf_event_attr_size *attr = (const struct perf_event_attr_size *)args->args[0], *attr_read;
- unsigned int len = sizeof(augmented_args->args);
+ unsigned int len = sizeof(u64) + sizeof(augmented_args->args); // the size + err in all 'augmented_arg' structs
if (augmented_args == NULL)
goto failure;
- if (bpf_probe_read_user(&augmented_args->__data, sizeof(*attr), attr) < 0)
+ if (bpf_probe_read_user(&augmented_args->arg.value, sizeof(*attr), attr) < 0)
goto failure;
- attr_read = (const struct perf_event_attr_size *)augmented_args->__data;
+ attr_read = (const struct perf_event_attr_size *)augmented_args->arg.value;
__u32 size = attr_read->size;
if (!size)
size = PERF_ATTR_SIZE_VER0;
- if (size > sizeof(augmented_args->__data))
+ if (size > sizeof(augmented_args->arg.value))
goto failure;
// Now that we read attr->size and tested it against the size limits, read it completely
- if (bpf_probe_read_user(&augmented_args->__data, size, attr) < 0)
+ if (bpf_probe_read_user(&augmented_args->arg.value, size, attr) < 0)
goto failure;
return augmented__output(args, augmented_args, len + size);
{
struct augmented_args_payload *augmented_args = augmented_args_payload();
const void *rqtp_arg = (const void *)args->args[2];
- unsigned int len = sizeof(augmented_args->args);
+ unsigned int len = sizeof(u64) + sizeof(augmented_args->args); // the size + err in all 'augmented_arg' structs
__u32 size = sizeof(struct timespec64);
if (augmented_args == NULL)
goto failure;
- if (size > sizeof(augmented_args->__data))
+ if (size > sizeof(augmented_args->arg.value))
goto failure;
- bpf_probe_read_user(&augmented_args->__data, size, rqtp_arg);
+ bpf_probe_read_user(&augmented_args->arg.value, size, rqtp_arg);
return augmented__output(args, augmented_args, len + size);
failure:
if (augmented_args == NULL)
goto failure;
- if (size > sizeof(augmented_args->__data))
+ if (size > sizeof(augmented_args->arg.value))
goto failure;
- bpf_probe_read_user(&augmented_args->__data, size, req_arg);
+ bpf_probe_read_user(&augmented_args->arg.value, size, req_arg);
return augmented__output(args, augmented_args, len + size);
failure:
projects / users / willy / linux.git / commitdiff