diff options
| -rw-r--r-- | fs/select.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/fs/select.c b/fs/select.c index 8ed9da50896a..3d4f85defeab 100644 --- a/fs/select.c +++ b/fs/select.c @@ -29,6 +29,7 @@ #include <linux/sched/rt.h> #include <linux/freezer.h> #include <net/busy_poll.h> +#include <linux/vmalloc.h> #include <asm/uaccess.h> @@ -554,7 +555,7 @@ int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set_bits fds; void *bits; int ret, max_fds; - unsigned int size; + size_t size, alloc_size; struct fdtable *fdt; /* Allocate small arguments on the stack to save memory and be faster */ long stack_fds[SELECT_STACK_ALLOC/sizeof(long)]; @@ -581,7 +582,14 @@ int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, if (size > sizeof(stack_fds) / 6) { /* Not enough space in on-stack array; must use kmalloc */ ret = -ENOMEM; - bits = kmalloc(6 * size, GFP_KERNEL); + if (size > (SIZE_MAX / 6)) + goto out_nofds; + + alloc_size = 6 * size; + bits = kmalloc(alloc_size, GFP_KERNEL|__GFP_NOWARN); + if (!bits && alloc_size > PAGE_SIZE) + bits = vmalloc(alloc_size); + if (!bits) goto out_nofds; } @@ -618,7 +626,7 @@ int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, out: if (bits != stack_fds) - kfree(bits); + kvfree(bits); out_nofds: return ret; } |