1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 #include "bpf_iter.h" 4 #include <bpf/bpf_helpers.h> 5 6 char _license[] SEC("license") = "GPL"; 7 8 /* Copied from mm.h */ 9 #define VM_READ 0x00000001 10 #define VM_WRITE 0x00000002 11 #define VM_EXEC 0x00000004 12 #define VM_MAYSHARE 0x00000080 13 14 /* Copied from kdev_t.h */ 15 #define MINORBITS 20 16 #define MINORMASK ((1U << MINORBITS) - 1) 17 #define MAJOR(dev) ((unsigned int) ((dev) >> MINORBITS)) 18 #define MINOR(dev) ((unsigned int) ((dev) & MINORMASK)) 19 20 #define D_PATH_BUF_SIZE 1024 21 char d_path_buf[D_PATH_BUF_SIZE] = {}; 22 __u32 pid = 0; 23 __u32 one_task = 0; 24 __u32 one_task_error = 0; 25 26 SEC("iter/task_vma") int proc_maps(struct bpf_iter__task_vma *ctx) 27 { 28 struct vm_area_struct *vma = ctx->vma; 29 struct seq_file *seq = ctx->meta->seq; 30 struct task_struct *task = ctx->task; 31 struct file *file; 32 char perm_str[] = "----"; 33 34 if (task == (void *)0 || vma == (void *)0) 35 return 0; 36 37 file = vma->vm_file; 38 if (task->tgid != pid) { 39 if (one_task) 40 one_task_error = 1; 41 return 0; 42 } 43 perm_str[0] = (vma->vm_flags & VM_READ) ? 'r' : '-'; 44 perm_str[1] = (vma->vm_flags & VM_WRITE) ? 'w' : '-'; 45 perm_str[2] = (vma->vm_flags & VM_EXEC) ? 'x' : '-'; 46 perm_str[3] = (vma->vm_flags & VM_MAYSHARE) ? 's' : 'p'; 47 BPF_SEQ_PRINTF(seq, "%08llx-%08llx %s ", vma->vm_start, vma->vm_end, perm_str); 48 49 if (file) { 50 __u32 dev = file->f_inode->i_sb->s_dev; 51 52 bpf_d_path(&file->f_path, d_path_buf, D_PATH_BUF_SIZE); 53 54 BPF_SEQ_PRINTF(seq, "%08llx ", vma->vm_pgoff << 12); 55 BPF_SEQ_PRINTF(seq, "%02x:%02x %u", MAJOR(dev), MINOR(dev), 56 file->f_inode->i_ino); 57 BPF_SEQ_PRINTF(seq, "\t%s\n", d_path_buf); 58 } else { 59 BPF_SEQ_PRINTF(seq, "%08llx 00:00 0\n", 0ULL); 60 } 61 return 0; 62 } 63