diff options
Diffstat (limited to 'fs/select.c')
| -rw-r--r-- | fs/select.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/fs/select.c b/fs/select.c index b80e7eb0ac0..f10a10317d5 100644 --- a/fs/select.c +++ b/fs/select.c @@ -22,6 +22,7 @@ #include <linux/personality.h> /* for STICKY_TIMEOUTS */ #include <linux/file.h> #include <linux/fs.h> +#include <linux/rcupdate.h> #include <asm/uaccess.h> @@ -132,11 +133,13 @@ static int max_select_fd(unsigned long n, fd_set_bits *fds) unsigned long *open_fds; unsigned long set; int max; + struct fdtable *fdt; /* handle last in-complete long-word first */ set = ~(~0UL << (n & (__NFDBITS-1))); n /= __NFDBITS; - open_fds = current->files->open_fds->fds_bits+n; + fdt = files_fdtable(current->files); + open_fds = fdt->open_fds->fds_bits+n; max = 0; if (set) { set &= BITS(fds, n); @@ -183,9 +186,9 @@ int do_select(int n, fd_set_bits *fds, long *timeout) int retval, i; long __timeout = *timeout; - spin_lock(¤t->files->file_lock); + rcu_read_lock(); retval = max_select_fd(n, fds); - spin_unlock(¤t->files->file_lock); + rcu_read_unlock(); if (retval < 0) return retval; @@ -299,6 +302,7 @@ sys_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, s char *bits; long timeout; int ret, size, max_fdset; + struct fdtable *fdt; timeout = MAX_SCHEDULE_TIMEOUT; if (tvp) { @@ -326,7 +330,10 @@ sys_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, s goto out_nofds; /* max_fdset can increase, so grab it once to avoid race */ - max_fdset = current->files->max_fdset; + rcu_read_lock(); + fdt = files_fdtable(current->files); + max_fdset = fdt->max_fdset; + rcu_read_unlock(); if (n > max_fdset) n = max_fdset; @@ -464,9 +471,15 @@ asmlinkage long sys_poll(struct pollfd __user * ufds, unsigned int nfds, long ti unsigned int i; struct poll_list *head; struct poll_list *walk; + struct fdtable *fdt; + int max_fdset; /* Do a sanity check on nfds ... */ - if (nfds > current->files->max_fdset && nfds > OPEN_MAX) + rcu_read_lock(); + fdt = files_fdtable(current->files); + max_fdset = fdt->max_fdset; + rcu_read_unlock(); + if (nfds > max_fdset && nfds > OPEN_MAX) return -EINVAL; if (timeout) { |