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>

8 files changed, 12 insertions, 12 deletions

diff --git a/fs/attr.c b/fs/attr.c
index 0a6ea54cde7d..0815e93bb487 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -81,7 +81,7 @@ int inode_newsize_ok(const struct inode *inode, loff_t offset)
         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)
diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index fdd397099172..61dd00a6c7b4 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -247,7 +247,7 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
          * 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)
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 42c6b4a54445..e0e769bdca59 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -501,7 +501,7 @@ static int load_flat_file(struct linux_binprm * bprm,
          * 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) {
diff --git a/fs/exec.c b/fs/exec.c
index 591030735591..6348d79401de 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -195,7 +195,7 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
                  *    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 @@ int setup_arg_pages(struct linux_binprm *bprm,
 
 #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 @@ static int format_corename(char *corename, long signr)
                         /* 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 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
         struct coredump_params cprm = {
                 .signr = signr,
                 .regs = regs,
-                .limit = current->signal->rlim[RLIMIT_CORE].rlim_cur,
+                .limit = rlimit(RLIMIT_CORE),
         };
 
         audit_core_dumps(signr);
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 97e01dc0d95f..452d02f9075e 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -344,7 +344,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
         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) {
diff --git a/fs/file.c b/fs/file.c
index 38039af67663..34bb7f71d994 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -257,7 +257,7 @@ int expand_files(struct files_struct *files, int nr)
          * 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? */
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 18e20feee251..aa8637b81028 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -273,7 +273,7 @@ static inline void task_sig(struct seq_file *m, struct task_struct *p)
                 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 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
                 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) {
diff --git a/fs/select.c b/fs/select.c
index fd38ce2e32e3..73715e90030f 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -821,7 +821,7 @@ int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
         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);