#include <linux/smp_lock.h>
#include <linux/syscalls.h>
#include <linux/time.h>
+#include <linux/rcupdate.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>
/* POSIX-1996 leaves the case l->l_len < 0 undefined;
POSIX-2001 defines it. */
start += l->l_start;
- end = start + l->l_len - 1;
- if (l->l_len < 0) {
+ if (start < 0)
+ return -EINVAL;
+ fl->fl_end = OFFSET_MAX;
+ if (l->l_len > 0) {
+ end = start + l->l_len - 1;
+ fl->fl_end = end;
+ } else if (l->l_len < 0) {
end = start - 1;
+ fl->fl_end = end;
start += l->l_len;
+ if (start < 0)
+ return -EINVAL;
}
-
- if (start < 0)
- return -EINVAL;
- if (l->l_len > 0 && end < 0)
- return -EOVERFLOW;
-
fl->fl_start = start; /* we record the absolute position */
- fl->fl_end = end;
- if (l->l_len == 0)
- fl->fl_end = OFFSET_MAX;
+ if (fl->fl_end < fl->fl_start)
+ return -EOVERFLOW;
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
return -EINVAL;
}
- if (((start += l->l_start) < 0) || (l->l_len < 0))
+ start += l->l_start;
+ if (start < 0)
return -EINVAL;
- fl->fl_end = start + l->l_len - 1;
- if (l->l_len > 0 && fl->fl_end < 0)
- return -EOVERFLOW;
+ fl->fl_end = OFFSET_MAX;
+ if (l->l_len > 0) {
+ fl->fl_end = start + l->l_len - 1;
+ } else if (l->l_len < 0) {
+ fl->fl_end = start - 1;
+ start += l->l_len;
+ if (start < 0)
+ return -EINVAL;
+ }
fl->fl_start = start; /* we record the absolute position */
- if (l->l_len == 0)
- fl->fl_end = OFFSET_MAX;
+ if (fl->fl_end < fl->fl_start)
+ return -EOVERFLOW;
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
/* Detect adjacent or overlapping regions (if same lock type)
*/
if (request->fl_type == fl->fl_type) {
+ /* In all comparisons of start vs end, use
+ * "start - 1" rather than "end + 1". If end
+ * is OFFSET_MAX, end + 1 will become negative.
+ */
if (fl->fl_end < request->fl_start - 1)
goto next_lock;
/* If the next lock in the list has entirely bigger
* addresses than the new one, insert the lock here.
*/
- if (fl->fl_start > request->fl_end + 1)
+ if (fl->fl_start - 1 > request->fl_end)
break;
/* If we come here, the new and old lock are of the
{
struct files_struct *files = current->files;
int i, j;
+ struct fdtable *fdt;
if (from == files)
return;
lock_kernel();
j = 0;
+ rcu_read_lock();
+ fdt = files_fdtable(files);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
- if (i >= files->max_fdset || i >= files->max_fds)
+ if (i >= fdt->max_fdset || i >= fdt->max_fds)
break;
- set = files->open_fds->fds_bits[j++];
+ set = fdt->open_fds->fds_bits[j++];
while (set) {
if (set & 1) {
- struct file *file = files->fd[i];
+ struct file *file = fdt->fd[i];
if (file)
__steal_locks(file, from);
}
set >>= 1;
}
}
+ rcu_read_unlock();
unlock_kernel();
}
EXPORT_SYMBOL(steal_locks);