1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 #include "bpf_iter.h" 4 #include <bpf/bpf_helpers.h> 5 #include <bpf/bpf_tracing.h> 6 7 char _license[] SEC("license") = "GPL"; 8 9 /* Copied from mm.h */ 10 #define VM_READ 0x00000001 11 #define VM_WRITE 0x00000002 12 #define VM_EXEC 0x00000004 13 #define VM_MAYSHARE 0x00000080 14 15 /* Copied from kdev_t.h */ 16 #define MINORBITS 20 17 #define MINORMASK ((1U << MINORBITS) - 1) 18 #define MAJOR(dev) ((unsigned int) ((dev) >> MINORBITS)) 19 #define MINOR(dev) ((unsigned int) ((dev) & MINORMASK)) 20 21 #define D_PATH_BUF_SIZE 1024 22 char d_path_buf[D_PATH_BUF_SIZE] = {}; 23 __u32 pid = 0; 24 25 SEC("iter/task_vma") int proc_maps(struct bpf_iter__task_vma *ctx) 26 { 27 struct vm_area_struct *vma = ctx->vma; 28 struct seq_file *seq = ctx->meta->seq; 29 struct task_struct *task = ctx->task; 30 struct file *file; 31 char perm_str[] = "----"; 32 33 if (task == (void *)0 || vma == (void *)0) 34 return 0; 35 36 file = vma->vm_file; 37 if (task->tgid != pid) 38 return 0; 39 perm_str[0] = (vma->vm_flags & VM_READ) ? 'r' : '-'; 40 perm_str[1] = (vma->vm_flags & VM_WRITE) ? 'w' : '-'; 41 perm_str[2] = (vma->vm_flags & VM_EXEC) ? 'x' : '-'; 42 perm_str[3] = (vma->vm_flags & VM_MAYSHARE) ? 's' : 'p'; 43 BPF_SEQ_PRINTF(seq, "%08llx-%08llx %s ", vma->vm_start, vma->vm_end, perm_str); 44 45 if (file) { 46 __u32 dev = file->f_inode->i_sb->s_dev; 47 48 bpf_d_path(&file->f_path, d_path_buf, D_PATH_BUF_SIZE); 49 50 BPF_SEQ_PRINTF(seq, "%08llx ", vma->vm_pgoff << 12); 51 BPF_SEQ_PRINTF(seq, "%02x:%02x %u", MAJOR(dev), MINOR(dev), 52 file->f_inode->i_ino); 53 BPF_SEQ_PRINTF(seq, "\t%s\n", d_path_buf); 54 } else { 55 BPF_SEQ_PRINTF(seq, "%08llx 00:00 0\n", 0ULL); 56 } 57 return 0; 58 } 59