1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #include <linux/fs.h> 3 4 #define DEVCG_ACC_MKNOD 1 5 #define DEVCG_ACC_READ 2 6 #define DEVCG_ACC_WRITE 4 7 #define DEVCG_ACC_MASK (DEVCG_ACC_MKNOD | DEVCG_ACC_READ | DEVCG_ACC_WRITE) 8 9 #define DEVCG_DEV_BLOCK 1 10 #define DEVCG_DEV_CHAR 2 11 #define DEVCG_DEV_ALL 4 /* this represents all devices */ 12 13 14 #if defined(CONFIG_CGROUP_DEVICE) || defined(CONFIG_CGROUP_BPF) 15 int devcgroup_check_permission(short type, u32 major, u32 minor, 16 short access); 17 static inline int devcgroup_inode_permission(struct inode *inode, int mask) 18 { 19 short type, access = 0; 20 21 if (likely(!inode->i_rdev)) 22 return 0; 23 24 if (S_ISBLK(inode->i_mode)) 25 type = DEVCG_DEV_BLOCK; 26 else if (S_ISCHR(inode->i_mode)) 27 type = DEVCG_DEV_CHAR; 28 else 29 return 0; 30 31 if (mask & MAY_WRITE) 32 access |= DEVCG_ACC_WRITE; 33 if (mask & MAY_READ) 34 access |= DEVCG_ACC_READ; 35 36 return devcgroup_check_permission(type, imajor(inode), iminor(inode), 37 access); 38 } 39 40 static inline int devcgroup_inode_mknod(int mode, dev_t dev) 41 { 42 short type; 43 44 if (!S_ISBLK(mode) && !S_ISCHR(mode)) 45 return 0; 46 47 if (S_ISBLK(mode)) 48 type = DEVCG_DEV_BLOCK; 49 else 50 type = DEVCG_DEV_CHAR; 51 52 return devcgroup_check_permission(type, MAJOR(dev), MINOR(dev), 53 DEVCG_ACC_MKNOD); 54 } 55 56 #else 57 static inline int devcgroup_check_permission(short type, u32 major, u32 minor, 58 short access) 59 { return 0; } 60 static inline int devcgroup_inode_permission(struct inode *inode, int mask) 61 { return 0; } 62 static inline int devcgroup_inode_mknod(int mode, dev_t dev) 63 { return 0; } 64 #endif 65