fs: use rlimit helpers

Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in commit 3e10e716abf3 ("resource: add helpers for fetching rlimits") or ACCESS_ONCE if not applicable. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs: use rlimit helpers
Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in commit 3e10e716abf3 ("resource: add helpers for fetching rlimits") or ACCESS_ONCE if not applicable. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jiri Slaby · Linus Torvalds
1 parent 221e3ebf6d
Showing 8 changed files with 12 additions and 12 deletions Side-by-side Diff
fs/attr.c
fs/binfmt_aout.c
fs/binfmt_flat.c
fs/exec.c
fs/fcntl.c
fs/file.c
fs/proc/array.c
fs/select.c
@@ -81,7 +81,7 @@
 	if (inode->i_size < offset) {
 		unsigned long limit;
  
-		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+		limit = rlimit(RLIMIT_FSIZE);
 		if (limit != RLIM_INFINITY && offset > limit)
 			goto out_sig;
 		if (offset > inode->i_sb->s_maxbytes)
@@ -247,7 +247,7 @@
 	 * size limits imposed on them by creating programs with large
 	 * arrays in the data or bss.
 	 */
-	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
+	rlim = rlimit(RLIMIT_DATA);
 	if (rlim >= RLIM_INFINITY)
 		rlim = ~0;
 	if (ex.a_data + ex.a_bss > rlim)
@@ -501,7 +501,7 @@
 	 * size limits imposed on them by creating programs with large
 	 * arrays in the data or bss.
 	 */
-	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
+	rlim = rlimit(RLIMIT_DATA);
 	if (rlim >= RLIM_INFINITY)
 		rlim = ~0;
 	if (data_len + bss_len > rlim) {
@@ -195,7 +195,7 @@
 		 *    to work from.
 		 */
 		rlim = current->signal->rlim;
-		if (size > rlim[RLIMIT_STACK].rlim_cur / 4) {
+		if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur) / 4) {
 			put_page(page);
 			return NULL;
 		}
@@ -579,7 +579,7 @@
  
 #ifdef CONFIG_STACK_GROWSUP
 	/* Limit stack size to 1GB */
-	stack_base = current->signal->rlim[RLIMIT_STACK].rlim_max;
+	stack_base = rlimit_max(RLIMIT_STACK);
 	if (stack_base > (1 << 30))
 		stack_base = 1 << 30;
  
@@ -1535,7 +1535,7 @@
 			/* core limit size */
 			case 'c':
 				rc = snprintf(out_ptr, out_end - out_ptr,
-					      "%lu", current->signal->rlim[RLIMIT_CORE].rlim_cur);
+					      "%lu", rlimit(RLIMIT_CORE));
 				if (rc > out_end - out_ptr)
 					goto out;
 				out_ptr += rc;
@@ -1800,7 +1800,7 @@
 	struct coredump_params cprm = {
 		.signr = signr,
 		.regs = regs,
-		.limit = current->signal->rlim[RLIMIT_CORE].rlim_cur,
+		.limit = rlimit(RLIMIT_CORE),
 	};
  
 	audit_core_dumps(signr);
@@ -344,7 +344,7 @@
 	switch (cmd) {
 	case F_DUPFD:
 	case F_DUPFD_CLOEXEC:
-		if (arg >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
+		if (arg >= rlimit(RLIMIT_NOFILE))
 			break;
 		err = alloc_fd(arg, cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0);
 		if (err >= 0) {
@@ -257,7 +257,7 @@
 	 * N.B. For clone tasks sharing a files structure, this test
 	 * will limit the total number of files that can be opened.
 	 */
-	if (nr >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
+	if (nr >= rlimit(RLIMIT_NOFILE))
 		return -EMFILE;
  
 	/* Do we need to expand? */
@@ -273,7 +273,7 @@
 		rcu_read_lock();  /* FIXME: is this correct? */
 		qsize = atomic_read(&__task_cred(p)->user->sigpending);
 		rcu_read_unlock();
-		qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
+		qlim = task_rlimit(p, RLIMIT_SIGPENDING);
 		unlock_task_sighand(p, &flags);
 	}
  
@@ -420,7 +420,7 @@
 		cutime = sig->cutime;
 		cstime = sig->cstime;
 		cgtime = sig->cgtime;
-		rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
+		rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
  
 		/* add up live thread stats at the group level */
 		if (whole) {
@@ -821,7 +821,7 @@
  	struct poll_list *walk = head;
  	unsigned long todo = nfds;
  
-	if (nfds > current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
+	if (nfds > rlimit(RLIMIT_NOFILE))
 		return -EINVAL;
  
 	len = min_t(unsigned int, nfds, N_STACK_PPS);
...	...	@@ -81,7 +81,7 @@
81	81	if (inode->i_size < offset) {
82	82	unsigned long limit;
83	83
84		- limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
	84	+ limit = rlimit(RLIMIT_FSIZE);
85	85	if (limit != RLIM_INFINITY && offset > limit)
86	86	goto out_sig;
87	87	if (offset > inode->i_sb->s_maxbytes)
...	...	@@ -247,7 +247,7 @@
247	247	* size limits imposed on them by creating programs with large
248	248	* arrays in the data or bss.
249	249	*/
250		- rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
	250	+ rlim = rlimit(RLIMIT_DATA);
251	251	if (rlim >= RLIM_INFINITY)
252	252	rlim = ~0;
253	253	if (ex.a_data + ex.a_bss > rlim)
...	...	@@ -501,7 +501,7 @@
501	501	* size limits imposed on them by creating programs with large
502	502	* arrays in the data or bss.
503	503	*/
504		- rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
	504	+ rlim = rlimit(RLIMIT_DATA);
505	505	if (rlim >= RLIM_INFINITY)
506	506	rlim = ~0;
507	507	if (data_len + bss_len > rlim) {
...	...	@@ -195,7 +195,7 @@
195	195	* to work from.
196	196	*/
197	197	rlim = current->signal->rlim;
198		- if (size > rlim[RLIMIT_STACK].rlim_cur / 4) {
	198	+ if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur) / 4) {
199	199	put_page(page);
200	200	return NULL;
201	201	}
...	...	@@ -579,7 +579,7 @@
579	579
580	580	#ifdef CONFIG_STACK_GROWSUP
581	581	/* Limit stack size to 1GB */
582		- stack_base = current->signal->rlim[RLIMIT_STACK].rlim_max;
	582	+ stack_base = rlimit_max(RLIMIT_STACK);
583	583	if (stack_base > (1 << 30))
584	584	stack_base = 1 << 30;
585	585
...	...	@@ -1535,7 +1535,7 @@
1535	1535	/* core limit size */
1536	1536	case 'c':
1537	1537	rc = snprintf(out_ptr, out_end - out_ptr,
1538		- "%lu", current->signal->rlim[RLIMIT_CORE].rlim_cur);
	1538	+ "%lu", rlimit(RLIMIT_CORE));
1539	1539	if (rc > out_end - out_ptr)
1540	1540	goto out;
1541	1541	out_ptr += rc;
...	...	@@ -1800,7 +1800,7 @@
1800	1800	struct coredump_params cprm = {
1801	1801	.signr = signr,
1802	1802	.regs = regs,
1803		- .limit = current->signal->rlim[RLIMIT_CORE].rlim_cur,
	1803	+ .limit = rlimit(RLIMIT_CORE),
1804	1804	};
1805	1805
1806	1806	audit_core_dumps(signr);
...	...	@@ -344,7 +344,7 @@
344	344	switch (cmd) {
345	345	case F_DUPFD:
346	346	case F_DUPFD_CLOEXEC:
347		- if (arg >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
	347	+ if (arg >= rlimit(RLIMIT_NOFILE))
348	348	break;
349	349	err = alloc_fd(arg, cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0);
350	350	if (err >= 0) {
...	...	@@ -257,7 +257,7 @@
257	257	* N.B. For clone tasks sharing a files structure, this test
258	258	* will limit the total number of files that can be opened.
259	259	*/
260		- if (nr >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
	260	+ if (nr >= rlimit(RLIMIT_NOFILE))
261	261	return -EMFILE;
262	262
263	263	/* Do we need to expand? */
...	...	@@ -273,7 +273,7 @@
273	273	rcu_read_lock(); /* FIXME: is this correct? */
274	274	qsize = atomic_read(&__task_cred(p)->user->sigpending);
275	275	rcu_read_unlock();
276		- qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
	276	+ qlim = task_rlimit(p, RLIMIT_SIGPENDING);
277	277	unlock_task_sighand(p, &flags);
278	278	}
279	279
...	...	@@ -420,7 +420,7 @@
420	420	cutime = sig->cutime;
421	421	cstime = sig->cstime;
422	422	cgtime = sig->cgtime;
423		- rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
	423	+ rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
424	424
425	425	/* add up live thread stats at the group level */
426	426	if (whole) {
...	...	@@ -821,7 +821,7 @@
821	821	struct poll_list *walk = head;
822	822	unsigned long todo = nfds;
823	823
824		- if (nfds > current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
	824	+ if (nfds > rlimit(RLIMIT_NOFILE))
825	825	return -EINVAL;
826	826
827	827	len = min_t(unsigned int, nfds, N_STACK_PPS);