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author | Otavio Salvador <otavio@ossystems.com.br> | 2020-05-20 08:43:03 -0300 |
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committer | GitHub <noreply@github.com> | 2020-05-20 08:43:03 -0300 |
commit | 1279cd128bba968ebe0a2df7f7ae38bae90250ef (patch) | |
tree | df6b1a190760f51465122ca4c13492d5ac5984c6 /mm/usercopy.c | |
parent | 0a8ab17689e628c84a666195bfc6ab85d11cf057 (diff) | |
parent | 2ae782ca839e0ee07de37122ddea362adff2e975 (diff) |
Merge pull request #76 from toradex/4.9-2.3.x-imx
4.9 2.3.x imx
Diffstat (limited to 'mm/usercopy.c')
-rw-r--r-- | mm/usercopy.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/mm/usercopy.c b/mm/usercopy.c index 3c8da0af9695..c2de343baad4 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -15,6 +15,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/mm.h> +#include <linux/highmem.h> #include <linux/slab.h> #include <asm/sections.h> @@ -124,7 +125,7 @@ static inline const char *check_kernel_text_object(const void *ptr, static inline const char *check_bogus_address(const void *ptr, unsigned long n) { /* Reject if object wraps past end of memory. */ - if ((unsigned long)ptr + n < (unsigned long)ptr) + if ((unsigned long)ptr + (n - 1) < (unsigned long)ptr) return "<wrapped address>"; /* Reject if NULL or ZERO-allocation. */ @@ -217,7 +218,12 @@ static inline const char *check_heap_object(const void *ptr, unsigned long n, if (!virt_addr_valid(ptr)) return NULL; - page = virt_to_head_page(ptr); + /* + * When CONFIG_HIGHMEM=y, kmap_to_page() will give either the + * highmem page or fallback to virt_to_page(). The following + * is effectively a highmem-aware virt_to_head_page(). + */ + page = compound_head(kmap_to_page((void *)ptr)); /* Check slab allocator for flags and size. */ if (PageSlab(page)) |