ALSA: fm801: Fix double free in case of error in tuner detection

[pandora-kernel.git] / mm / swapfile.c

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 1b8c339..17bc224 100644 (file)
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1924,20 +1924,24 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
 
        /*
         * Find out how many pages are allowed for a single swap
-        * device. There are two limiting factors: 1) the number of
-        * bits for the swap offset in the swp_entry_t type and
-        * 2) the number of bits in the a swap pte as defined by
-        * the different architectures. In order to find the
-        * largest possible bit mask a swap entry with swap type 0
+        * device. There are three limiting factors: 1) the number
+        * of bits for the swap offset in the swp_entry_t type, and
+        * 2) the number of bits in the swap pte as defined by the
+        * the different architectures, and 3) the number of free bits
+        * in an exceptional radix_tree entry. In order to find the
+        * largest possible bit mask, a swap entry with swap type 0
         * and swap offset ~0UL is created, encoded to a swap pte,
-        * decoded to a swp_entry_t again and finally the swap
+        * decoded to a swp_entry_t again, and finally the swap
         * offset is extracted. This will mask all the bits from
         * the initial ~0UL mask that can't be encoded in either
         * the swp_entry_t or the architecture definition of a
-        * swap pte.
+        * swap pte.  Then the same is done for a radix_tree entry.
         */
        maxpages = swp_offset(pte_to_swp_entry(
-                       swp_entry_to_pte(swp_entry(0, ~0UL)))) + 1;
+                       swp_entry_to_pte(swp_entry(0, ~0UL))));
+       maxpages = swp_offset(radix_to_swp_entry(
+                       swp_to_radix_entry(swp_entry(0, maxpages)))) + 1;
+
        if (maxpages > swap_header->info.last_page) {
                maxpages = swap_header->info.last_page + 1;
                /* p->max is an unsigned int: don't overflow it */