1 /* 1 /* 2 * memfd_create system call and file sealing s 2 * memfd_create system call and file sealing support 3 * 3 * 4 * Code was originally included in shmem.c, an 4 * Code was originally included in shmem.c, and broken out to facilitate 5 * use by hugetlbfs as well as tmpfs. 5 * use by hugetlbfs as well as tmpfs. 6 * 6 * 7 * This file is released under the GPL. 7 * This file is released under the GPL. 8 */ 8 */ 9 9 10 #include <linux/fs.h> 10 #include <linux/fs.h> 11 #include <linux/vfs.h> 11 #include <linux/vfs.h> 12 #include <linux/pagemap.h> 12 #include <linux/pagemap.h> 13 #include <linux/file.h> 13 #include <linux/file.h> 14 #include <linux/mm.h> 14 #include <linux/mm.h> 15 #include <linux/sched/signal.h> 15 #include <linux/sched/signal.h> 16 #include <linux/khugepaged.h> 16 #include <linux/khugepaged.h> 17 #include <linux/syscalls.h> 17 #include <linux/syscalls.h> 18 #include <linux/hugetlb.h> 18 #include <linux/hugetlb.h> 19 #include <linux/shmem_fs.h> 19 #include <linux/shmem_fs.h> 20 #include <linux/memfd.h> 20 #include <linux/memfd.h> 21 #include <linux/pid_namespace.h> 21 #include <linux/pid_namespace.h> 22 #include <uapi/linux/memfd.h> 22 #include <uapi/linux/memfd.h> 23 23 24 /* 24 /* 25 * We need a tag: a new tag would expand every 25 * We need a tag: a new tag would expand every xa_node by 8 bytes, 26 * so reuse a tag which we firmly believe is n 26 * so reuse a tag which we firmly believe is never set or cleared on tmpfs 27 * or hugetlbfs because they are memory only f 27 * or hugetlbfs because they are memory only filesystems. 28 */ 28 */ 29 #define MEMFD_TAG_PINNED PAGECACHE_TAG_ 29 #define MEMFD_TAG_PINNED PAGECACHE_TAG_TOWRITE 30 #define LAST_SCAN 4 /* abo 30 #define LAST_SCAN 4 /* about 150ms max */ 31 31 32 static bool memfd_folio_has_extra_refs(struct << 33 { << 34 return folio_ref_count(folio) - folio_ << 35 folio_nr_pages(folio); << 36 } << 37 << 38 static void memfd_tag_pins(struct xa_state *xa 32 static void memfd_tag_pins(struct xa_state *xas) 39 { 33 { 40 struct folio *folio; !! 34 struct page *page; 41 int latency = 0; 35 int latency = 0; >> 36 int cache_count; 42 37 43 lru_add_drain(); 38 lru_add_drain(); 44 39 45 xas_lock_irq(xas); 40 xas_lock_irq(xas); 46 xas_for_each(xas, folio, ULONG_MAX) { !! 41 xas_for_each(xas, page, ULONG_MAX) { 47 if (!xa_is_value(folio) && mem !! 42 cache_count = 1; >> 43 if (!xa_is_value(page) && >> 44 PageTransHuge(page) && !PageHuge(page)) >> 45 cache_count = HPAGE_PMD_NR; >> 46 >> 47 if (!xa_is_value(page) && >> 48 page_count(page) - total_mapcount(page) != cache_count) 48 xas_set_mark(xas, MEMF 49 xas_set_mark(xas, MEMFD_TAG_PINNED); >> 50 if (cache_count != 1) >> 51 xas_set(xas, page->index + cache_count); 49 52 50 if (++latency < XA_CHECK_SCHED !! 53 latency += cache_count; >> 54 if (latency < XA_CHECK_SCHED) 51 continue; 55 continue; 52 latency = 0; 56 latency = 0; 53 57 54 xas_pause(xas); 58 xas_pause(xas); 55 xas_unlock_irq(xas); 59 xas_unlock_irq(xas); 56 cond_resched(); 60 cond_resched(); 57 xas_lock_irq(xas); 61 xas_lock_irq(xas); 58 } 62 } 59 xas_unlock_irq(xas); 63 xas_unlock_irq(xas); 60 } 64 } 61 65 62 /* 66 /* 63 * This is a helper function used by memfd_pin << 64 * It is mainly called to allocate a folio in << 65 * (memfd_pin_folios()) cannot find a folio in << 66 * index in the mapping. << 67 */ << 68 struct folio *memfd_alloc_folio(struct file *m << 69 { << 70 #ifdef CONFIG_HUGETLB_PAGE << 71 struct folio *folio; << 72 gfp_t gfp_mask; << 73 int err; << 74 << 75 if (is_file_hugepages(memfd)) { << 76 /* << 77 * The folio would most likely << 78 * therefore, we have zone mem << 79 * alloc from. Also, the folio << 80 * amount of time, so it is no << 81 */ << 82 struct hstate *h = hstate_file << 83 << 84 gfp_mask = htlb_alloc_mask(h); << 85 gfp_mask &= ~(__GFP_HIGHMEM | << 86 idx >>= huge_page_order(h); << 87 << 88 folio = alloc_hugetlb_folio_re << 89 << 90 << 91 << 92 if (folio) { << 93 err = hugetlb_add_to_p << 94 << 95 << 96 if (err) { << 97 folio_put(foli << 98 return ERR_PTR << 99 } << 100 folio_unlock(folio); << 101 return folio; << 102 } << 103 return ERR_PTR(-ENOMEM); << 104 } << 105 #endif << 106 return shmem_read_folio(memfd->f_mappi << 107 } << 108 << 109 /* << 110 * Setting SEAL_WRITE requires us to verify th 67 * Setting SEAL_WRITE requires us to verify there's no pending writer. However, 111 * via get_user_pages(), drivers might have so 68 * via get_user_pages(), drivers might have some pending I/O without any active 112 * user-space mappings (eg., direct-IO, AIO). !! 69 * user-space mappings (eg., direct-IO, AIO). Therefore, we look at all pages 113 * and see whether it has an elevated ref-coun 70 * and see whether it has an elevated ref-count. If so, we tag them and wait for 114 * them to be dropped. 71 * them to be dropped. 115 * The caller must guarantee that no new user 72 * The caller must guarantee that no new user will acquire writable references 116 * to those folios to avoid races. !! 73 * to those pages to avoid races. 117 */ 74 */ 118 static int memfd_wait_for_pins(struct address_ 75 static int memfd_wait_for_pins(struct address_space *mapping) 119 { 76 { 120 XA_STATE(xas, &mapping->i_pages, 0); 77 XA_STATE(xas, &mapping->i_pages, 0); 121 struct folio *folio; !! 78 struct page *page; 122 int error, scan; 79 int error, scan; 123 80 124 memfd_tag_pins(&xas); 81 memfd_tag_pins(&xas); 125 82 126 error = 0; 83 error = 0; 127 for (scan = 0; scan <= LAST_SCAN; scan 84 for (scan = 0; scan <= LAST_SCAN; scan++) { 128 int latency = 0; 85 int latency = 0; >> 86 int cache_count; 129 87 130 if (!xas_marked(&xas, MEMFD_TA 88 if (!xas_marked(&xas, MEMFD_TAG_PINNED)) 131 break; 89 break; 132 90 133 if (!scan) 91 if (!scan) 134 lru_add_drain_all(); 92 lru_add_drain_all(); 135 else if (schedule_timeout_kill 93 else if (schedule_timeout_killable((HZ << scan) / 200)) 136 scan = LAST_SCAN; 94 scan = LAST_SCAN; 137 95 138 xas_set(&xas, 0); 96 xas_set(&xas, 0); 139 xas_lock_irq(&xas); 97 xas_lock_irq(&xas); 140 xas_for_each_marked(&xas, foli !! 98 xas_for_each_marked(&xas, page, ULONG_MAX, MEMFD_TAG_PINNED) { 141 bool clear = true; 99 bool clear = true; 142 100 143 if (!xa_is_value(folio !! 101 cache_count = 1; 144 memfd_folio_has_ex !! 102 if (!xa_is_value(page) && >> 103 PageTransHuge(page) && !PageHuge(page)) >> 104 cache_count = HPAGE_PMD_NR; >> 105 >> 106 if (!xa_is_value(page) && cache_count != >> 107 page_count(page) - total_mapcount(page)) { 145 /* 108 /* 146 * On the last 109 * On the last scan, we clean up all those tags 147 * we inserted 110 * we inserted; but make a note that we still 148 * found folio !! 111 * found pages pinned. 149 */ 112 */ 150 if (scan == LA 113 if (scan == LAST_SCAN) 151 error 114 error = -EBUSY; 152 else 115 else 153 clear 116 clear = false; 154 } 117 } 155 if (clear) 118 if (clear) 156 xas_clear_mark 119 xas_clear_mark(&xas, MEMFD_TAG_PINNED); 157 120 158 if (++latency < XA_CHE !! 121 latency += cache_count; >> 122 if (latency < XA_CHECK_SCHED) 159 continue; 123 continue; 160 latency = 0; 124 latency = 0; 161 125 162 xas_pause(&xas); 126 xas_pause(&xas); 163 xas_unlock_irq(&xas); 127 xas_unlock_irq(&xas); 164 cond_resched(); 128 cond_resched(); 165 xas_lock_irq(&xas); 129 xas_lock_irq(&xas); 166 } 130 } 167 xas_unlock_irq(&xas); 131 xas_unlock_irq(&xas); 168 } 132 } 169 133 170 return error; 134 return error; 171 } 135 } 172 136 173 static unsigned int *memfd_file_seals_ptr(stru 137 static unsigned int *memfd_file_seals_ptr(struct file *file) 174 { 138 { 175 if (shmem_file(file)) 139 if (shmem_file(file)) 176 return &SHMEM_I(file_inode(fil 140 return &SHMEM_I(file_inode(file))->seals; 177 141 178 #ifdef CONFIG_HUGETLBFS 142 #ifdef CONFIG_HUGETLBFS 179 if (is_file_hugepages(file)) 143 if (is_file_hugepages(file)) 180 return &HUGETLBFS_I(file_inode 144 return &HUGETLBFS_I(file_inode(file))->seals; 181 #endif 145 #endif 182 146 183 return NULL; 147 return NULL; 184 } 148 } 185 149 186 #define F_ALL_SEALS (F_SEAL_SEAL | \ 150 #define F_ALL_SEALS (F_SEAL_SEAL | \ 187 F_SEAL_EXEC | \ 151 F_SEAL_EXEC | \ 188 F_SEAL_SHRINK | \ 152 F_SEAL_SHRINK | \ 189 F_SEAL_GROW | \ 153 F_SEAL_GROW | \ 190 F_SEAL_WRITE | \ 154 F_SEAL_WRITE | \ 191 F_SEAL_FUTURE_WRITE) 155 F_SEAL_FUTURE_WRITE) 192 156 193 static int memfd_add_seals(struct file *file, 157 static int memfd_add_seals(struct file *file, unsigned int seals) 194 { 158 { 195 struct inode *inode = file_inode(file) 159 struct inode *inode = file_inode(file); 196 unsigned int *file_seals; 160 unsigned int *file_seals; 197 int error; 161 int error; 198 162 199 /* 163 /* 200 * SEALING 164 * SEALING 201 * Sealing allows multiple parties to 165 * Sealing allows multiple parties to share a tmpfs or hugetlbfs file 202 * but restrict access to a specific s 166 * but restrict access to a specific subset of file operations. Seals 203 * can only be added, but never remove 167 * can only be added, but never removed. This way, mutually untrusted 204 * parties can share common memory reg 168 * parties can share common memory regions with a well-defined policy. 205 * A malicious peer can thus never per 169 * A malicious peer can thus never perform unwanted operations on a 206 * shared object. 170 * shared object. 207 * 171 * 208 * Seals are only supported on special 172 * Seals are only supported on special tmpfs or hugetlbfs files and 209 * always affect the whole underlying 173 * always affect the whole underlying inode. Once a seal is set, it 210 * may prevent some kinds of access to 174 * may prevent some kinds of access to the file. Currently, the 211 * following seals are defined: 175 * following seals are defined: 212 * SEAL_SEAL: Prevent further seals 176 * SEAL_SEAL: Prevent further seals from being set on this file 213 * SEAL_SHRINK: Prevent the file fro 177 * SEAL_SHRINK: Prevent the file from shrinking 214 * SEAL_GROW: Prevent the file from 178 * SEAL_GROW: Prevent the file from growing 215 * SEAL_WRITE: Prevent write access 179 * SEAL_WRITE: Prevent write access to the file 216 * SEAL_EXEC: Prevent modification o 180 * SEAL_EXEC: Prevent modification of the exec bits in the file mode 217 * 181 * 218 * As we don't require any trust relat 182 * As we don't require any trust relationship between two parties, we 219 * must prevent seals from being remov 183 * must prevent seals from being removed. Therefore, sealing a file 220 * only adds a given set of seals to t 184 * only adds a given set of seals to the file, it never touches 221 * existing seals. Furthermore, the "s 185 * existing seals. Furthermore, the "setting seals"-operation can be 222 * sealed itself, which basically prev 186 * sealed itself, which basically prevents any further seal from being 223 * added. 187 * added. 224 * 188 * 225 * Semantics of sealing are only defin 189 * Semantics of sealing are only defined on volatile files. Only 226 * anonymous tmpfs and hugetlbfs files 190 * anonymous tmpfs and hugetlbfs files support sealing. More 227 * importantly, seals are never writte 191 * importantly, seals are never written to disk. Therefore, there's 228 * no plan to support it on other file 192 * no plan to support it on other file types. 229 */ 193 */ 230 194 231 if (!(file->f_mode & FMODE_WRITE)) 195 if (!(file->f_mode & FMODE_WRITE)) 232 return -EPERM; 196 return -EPERM; 233 if (seals & ~(unsigned int)F_ALL_SEALS 197 if (seals & ~(unsigned int)F_ALL_SEALS) 234 return -EINVAL; 198 return -EINVAL; 235 199 236 inode_lock(inode); 200 inode_lock(inode); 237 201 238 file_seals = memfd_file_seals_ptr(file 202 file_seals = memfd_file_seals_ptr(file); 239 if (!file_seals) { 203 if (!file_seals) { 240 error = -EINVAL; 204 error = -EINVAL; 241 goto unlock; 205 goto unlock; 242 } 206 } 243 207 244 if (*file_seals & F_SEAL_SEAL) { 208 if (*file_seals & F_SEAL_SEAL) { 245 error = -EPERM; 209 error = -EPERM; 246 goto unlock; 210 goto unlock; 247 } 211 } 248 212 249 if ((seals & F_SEAL_WRITE) && !(*file_ 213 if ((seals & F_SEAL_WRITE) && !(*file_seals & F_SEAL_WRITE)) { 250 error = mapping_deny_writable( 214 error = mapping_deny_writable(file->f_mapping); 251 if (error) 215 if (error) 252 goto unlock; 216 goto unlock; 253 217 254 error = memfd_wait_for_pins(fi 218 error = memfd_wait_for_pins(file->f_mapping); 255 if (error) { 219 if (error) { 256 mapping_allow_writable 220 mapping_allow_writable(file->f_mapping); 257 goto unlock; 221 goto unlock; 258 } 222 } 259 } 223 } 260 224 261 /* 225 /* 262 * SEAL_EXEC implys SEAL_WRITE, making 226 * SEAL_EXEC implys SEAL_WRITE, making W^X from the start. 263 */ 227 */ 264 if (seals & F_SEAL_EXEC && inode->i_mo 228 if (seals & F_SEAL_EXEC && inode->i_mode & 0111) 265 seals |= F_SEAL_SHRINK|F_SEAL_ 229 seals |= F_SEAL_SHRINK|F_SEAL_GROW|F_SEAL_WRITE|F_SEAL_FUTURE_WRITE; 266 230 267 *file_seals |= seals; 231 *file_seals |= seals; 268 error = 0; 232 error = 0; 269 233 270 unlock: 234 unlock: 271 inode_unlock(inode); 235 inode_unlock(inode); 272 return error; 236 return error; 273 } 237 } 274 238 275 static int memfd_get_seals(struct file *file) 239 static int memfd_get_seals(struct file *file) 276 { 240 { 277 unsigned int *seals = memfd_file_seals 241 unsigned int *seals = memfd_file_seals_ptr(file); 278 242 279 return seals ? *seals : -EINVAL; 243 return seals ? *seals : -EINVAL; 280 } 244 } 281 245 282 long memfd_fcntl(struct file *file, unsigned i !! 246 long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg) 283 { 247 { 284 long error; 248 long error; 285 249 286 switch (cmd) { 250 switch (cmd) { 287 case F_ADD_SEALS: 251 case F_ADD_SEALS: >> 252 /* disallow upper 32bit */ >> 253 if (arg > UINT_MAX) >> 254 return -EINVAL; >> 255 288 error = memfd_add_seals(file, 256 error = memfd_add_seals(file, arg); 289 break; 257 break; 290 case F_GET_SEALS: 258 case F_GET_SEALS: 291 error = memfd_get_seals(file); 259 error = memfd_get_seals(file); 292 break; 260 break; 293 default: 261 default: 294 error = -EINVAL; 262 error = -EINVAL; 295 break; 263 break; 296 } 264 } 297 265 298 return error; 266 return error; 299 } 267 } 300 268 301 #define MFD_NAME_PREFIX "memfd:" 269 #define MFD_NAME_PREFIX "memfd:" 302 #define MFD_NAME_PREFIX_LEN (sizeof(MFD_NAME_P 270 #define MFD_NAME_PREFIX_LEN (sizeof(MFD_NAME_PREFIX) - 1) 303 #define MFD_NAME_MAX_LEN (NAME_MAX - MFD_NAME_ 271 #define MFD_NAME_MAX_LEN (NAME_MAX - MFD_NAME_PREFIX_LEN) 304 272 305 #define MFD_ALL_FLAGS (MFD_CLOEXEC | MFD_ALLOW 273 #define MFD_ALL_FLAGS (MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB | MFD_NOEXEC_SEAL | MFD_EXEC) 306 274 307 static int check_sysctl_memfd_noexec(unsigned << 308 { << 309 #ifdef CONFIG_SYSCTL << 310 struct pid_namespace *ns = task_active << 311 int sysctl = pidns_memfd_noexec_scope( << 312 << 313 if (!(*flags & (MFD_EXEC | MFD_NOEXEC_ << 314 if (sysctl >= MEMFD_NOEXEC_SCO << 315 *flags |= MFD_NOEXEC_S << 316 else << 317 *flags |= MFD_EXEC; << 318 } << 319 << 320 if (!(*flags & MFD_NOEXEC_SEAL) && sys << 321 pr_err_ratelimited( << 322 "%s[%d]: memfd_create( << 323 current->comm, task_pi << 324 return -EACCES; << 325 } << 326 #endif << 327 return 0; << 328 } << 329 << 330 SYSCALL_DEFINE2(memfd_create, 275 SYSCALL_DEFINE2(memfd_create, 331 const char __user *, uname, 276 const char __user *, uname, 332 unsigned int, flags) 277 unsigned int, flags) 333 { 278 { >> 279 char comm[TASK_COMM_LEN]; 334 unsigned int *file_seals; 280 unsigned int *file_seals; 335 struct file *file; 281 struct file *file; 336 int fd, error; 282 int fd, error; 337 char *name; 283 char *name; 338 long len; 284 long len; 339 285 340 if (!(flags & MFD_HUGETLB)) { 286 if (!(flags & MFD_HUGETLB)) { 341 if (flags & ~(unsigned int)MFD 287 if (flags & ~(unsigned int)MFD_ALL_FLAGS) 342 return -EINVAL; 288 return -EINVAL; 343 } else { 289 } else { 344 /* Allow huge page size encodi 290 /* Allow huge page size encoding in flags. */ 345 if (flags & ~(unsigned int)(MF 291 if (flags & ~(unsigned int)(MFD_ALL_FLAGS | 346 (MFD_HUGE_MASK 292 (MFD_HUGE_MASK << MFD_HUGE_SHIFT))) 347 return -EINVAL; 293 return -EINVAL; 348 } 294 } 349 295 350 /* Invalid if both EXEC and NOEXEC_SEA 296 /* Invalid if both EXEC and NOEXEC_SEAL are set.*/ 351 if ((flags & MFD_EXEC) && (flags & MFD 297 if ((flags & MFD_EXEC) && (flags & MFD_NOEXEC_SEAL)) 352 return -EINVAL; 298 return -EINVAL; 353 299 354 error = check_sysctl_memfd_noexec(&fla !! 300 if (!(flags & (MFD_EXEC | MFD_NOEXEC_SEAL))) { 355 if (error < 0) !! 301 #ifdef CONFIG_SYSCTL 356 return error; !! 302 int sysctl = MEMFD_NOEXEC_SCOPE_EXEC; >> 303 struct pid_namespace *ns; >> 304 >> 305 ns = task_active_pid_ns(current); >> 306 if (ns) >> 307 sysctl = ns->memfd_noexec_scope; >> 308 >> 309 switch (sysctl) { >> 310 case MEMFD_NOEXEC_SCOPE_EXEC: >> 311 flags |= MFD_EXEC; >> 312 break; >> 313 case MEMFD_NOEXEC_SCOPE_NOEXEC_SEAL: >> 314 flags |= MFD_NOEXEC_SEAL; >> 315 break; >> 316 default: >> 317 pr_warn_once( >> 318 "memfd_create(): MFD_NOEXEC_SEAL is enforced, pid=%d '%s'\n", >> 319 task_pid_nr(current), get_task_comm(comm, current)); >> 320 return -EINVAL; >> 321 } >> 322 #else >> 323 flags |= MFD_EXEC; >> 324 #endif >> 325 pr_warn_once( >> 326 "memfd_create() without MFD_EXEC nor MFD_NOEXEC_SEAL, pid=%d '%s'\n", >> 327 task_pid_nr(current), get_task_comm(comm, current)); >> 328 } 357 329 358 /* length includes terminating zero */ 330 /* length includes terminating zero */ 359 len = strnlen_user(uname, MFD_NAME_MAX 331 len = strnlen_user(uname, MFD_NAME_MAX_LEN + 1); 360 if (len <= 0) 332 if (len <= 0) 361 return -EFAULT; 333 return -EFAULT; 362 if (len > MFD_NAME_MAX_LEN + 1) 334 if (len > MFD_NAME_MAX_LEN + 1) 363 return -EINVAL; 335 return -EINVAL; 364 336 365 name = kmalloc(len + MFD_NAME_PREFIX_L 337 name = kmalloc(len + MFD_NAME_PREFIX_LEN, GFP_KERNEL); 366 if (!name) 338 if (!name) 367 return -ENOMEM; 339 return -ENOMEM; 368 340 369 strcpy(name, MFD_NAME_PREFIX); 341 strcpy(name, MFD_NAME_PREFIX); 370 if (copy_from_user(&name[MFD_NAME_PREF 342 if (copy_from_user(&name[MFD_NAME_PREFIX_LEN], uname, len)) { 371 error = -EFAULT; 343 error = -EFAULT; 372 goto err_name; 344 goto err_name; 373 } 345 } 374 346 375 /* terminating-zero may have changed a 347 /* terminating-zero may have changed after strnlen_user() returned */ 376 if (name[len + MFD_NAME_PREFIX_LEN - 1 348 if (name[len + MFD_NAME_PREFIX_LEN - 1]) { 377 error = -EFAULT; 349 error = -EFAULT; 378 goto err_name; 350 goto err_name; 379 } 351 } 380 352 381 fd = get_unused_fd_flags((flags & MFD_ 353 fd = get_unused_fd_flags((flags & MFD_CLOEXEC) ? O_CLOEXEC : 0); 382 if (fd < 0) { 354 if (fd < 0) { 383 error = fd; 355 error = fd; 384 goto err_name; 356 goto err_name; 385 } 357 } 386 358 387 if (flags & MFD_HUGETLB) { 359 if (flags & MFD_HUGETLB) { 388 file = hugetlb_file_setup(name 360 file = hugetlb_file_setup(name, 0, VM_NORESERVE, 389 HUGETL 361 HUGETLB_ANONHUGE_INODE, 390 (flags 362 (flags >> MFD_HUGE_SHIFT) & 391 MFD_HU 363 MFD_HUGE_MASK); 392 } else 364 } else 393 file = shmem_file_setup(name, 365 file = shmem_file_setup(name, 0, VM_NORESERVE); 394 if (IS_ERR(file)) { 366 if (IS_ERR(file)) { 395 error = PTR_ERR(file); 367 error = PTR_ERR(file); 396 goto err_fd; 368 goto err_fd; 397 } 369 } 398 file->f_mode |= FMODE_LSEEK | FMODE_PR 370 file->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; 399 file->f_flags |= O_LARGEFILE; 371 file->f_flags |= O_LARGEFILE; 400 372 401 if (flags & MFD_NOEXEC_SEAL) { 373 if (flags & MFD_NOEXEC_SEAL) { 402 struct inode *inode = file_ino 374 struct inode *inode = file_inode(file); 403 375 404 inode->i_mode &= ~0111; 376 inode->i_mode &= ~0111; 405 file_seals = memfd_file_seals_ 377 file_seals = memfd_file_seals_ptr(file); 406 if (file_seals) { 378 if (file_seals) { 407 *file_seals &= ~F_SEAL 379 *file_seals &= ~F_SEAL_SEAL; 408 *file_seals |= F_SEAL_ 380 *file_seals |= F_SEAL_EXEC; 409 } 381 } 410 } else if (flags & MFD_ALLOW_SEALING) 382 } else if (flags & MFD_ALLOW_SEALING) { 411 /* MFD_EXEC and MFD_ALLOW_SEAL 383 /* MFD_EXEC and MFD_ALLOW_SEALING are set */ 412 file_seals = memfd_file_seals_ 384 file_seals = memfd_file_seals_ptr(file); 413 if (file_seals) 385 if (file_seals) 414 *file_seals &= ~F_SEAL 386 *file_seals &= ~F_SEAL_SEAL; 415 } 387 } 416 388 417 fd_install(fd, file); 389 fd_install(fd, file); 418 kfree(name); 390 kfree(name); 419 return fd; 391 return fd; 420 392 421 err_fd: 393 err_fd: 422 put_unused_fd(fd); 394 put_unused_fd(fd); 423 err_name: 395 err_name: 424 kfree(name); 396 kfree(name); 425 return error; 397 return error; 426 } 398 } 427 399
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