Revert "time: Remove xtime_cache"

[safe/jmp/linux-2.6] / kernel / module.c

diff --git a/kernel/module.c b/kernel/module.c
index 64787cd..e96b8ed 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -880,11 +880,23 @@ static int try_to_force_load(struct module *mod, const char *reason)
 }
 
 #ifdef CONFIG_MODVERSIONS
+/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
+static unsigned long maybe_relocated(unsigned long crc,
+                                    const struct module *crc_owner)
+{
+#ifdef ARCH_RELOCATES_KCRCTAB
+       if (crc_owner == NULL)
+               return crc - (unsigned long)reloc_start;
+#endif
+       return crc;
+}
+
 static int check_version(Elf_Shdr *sechdrs,
                         unsigned int versindex,
                         const char *symname,
                         struct module *mod, 
-                        const unsigned long *crc)
+                        const unsigned long *crc,
+                        const struct module *crc_owner)
 {
        unsigned int i, num_versions;
        struct modversion_info *versions;
@@ -905,10 +917,10 @@ static int check_version(Elf_Shdr *sechdrs,
                if (strcmp(versions[i].name, symname) != 0)
                        continue;
 
-               if (versions[i].crc == *crc)
+               if (versions[i].crc == maybe_relocated(*crc, crc_owner))
                        return 1;
                DEBUGP("Found checksum %lX vs module %lX\n",
-                      *crc, versions[i].crc);
+                      maybe_relocated(*crc, crc_owner), versions[i].crc);
                goto bad_version;
        }
 
@@ -931,7 +943,8 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
        if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
                         &crc, true, false))
                BUG();
-       return check_version(sechdrs, versindex, "module_layout", mod, crc);
+       return check_version(sechdrs, versindex, "module_layout", mod, crc,
+                            NULL);
 }
 
 /* First part is kernel version, which we ignore if module has crcs. */
@@ -949,7 +962,8 @@ static inline int check_version(Elf_Shdr *sechdrs,
                                unsigned int versindex,
                                const char *symname,
                                struct module *mod, 
-                               const unsigned long *crc)
+                               const unsigned long *crc,
+                               const struct module *crc_owner)
 {
        return 1;
 }
@@ -984,8 +998,8 @@ static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
        /* use_module can fail due to OOM,
           or module initialization or unloading */
        if (sym) {
-               if (!check_version(sechdrs, versindex, name, mod, crc) ||
-                   !use_module(mod, owner))
+               if (!check_version(sechdrs, versindex, name, mod, crc, owner)
+                   || !use_module(mod, owner))
                        sym = NULL;
        }
        return sym;
@@ -1037,7 +1051,8 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect,
 
        /* Count loaded sections and allocate structures */
        for (i = 0; i < nsect; i++)
-               if (sechdrs[i].sh_flags & SHF_ALLOC)
+               if (sechdrs[i].sh_flags & SHF_ALLOC
+                   && sechdrs[i].sh_size)
                        nloaded++;
        size[0] = ALIGN(sizeof(*sect_attrs)
                        + nloaded * sizeof(sect_attrs->attrs[0]),
@@ -1057,6 +1072,8 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect,
        for (i = 0; i < nsect; i++) {
                if (! (sechdrs[i].sh_flags & SHF_ALLOC))
                        continue;
+               if (!sechdrs[i].sh_size)
+                       continue;
                sattr->address = sechdrs[i].sh_addr;
                sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
                                        GFP_KERNEL);
@@ -1893,9 +1910,7 @@ static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
        unsigned int i;
 
        /* only scan the sections containing data */
-       kmemleak_scan_area(mod->module_core, (unsigned long)mod -
-                          (unsigned long)mod->module_core,
-                          sizeof(struct module), GFP_KERNEL);
+       kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
 
        for (i = 1; i < hdr->e_shnum; i++) {
                if (!(sechdrs[i].sh_flags & SHF_ALLOC))
@@ -1904,8 +1919,7 @@ static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
                    && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
                        continue;
 
-               kmemleak_scan_area(mod->module_core, sechdrs[i].sh_addr -
-                                  (unsigned long)mod->module_core,
+               kmemleak_scan_area((void *)sechdrs[i].sh_addr,
                                   sechdrs[i].sh_size, GFP_KERNEL);
        }
 }
@@ -2233,6 +2247,12 @@ static noinline struct module *load_module(void __user *umod,
                                         "_ftrace_events",
                                         sizeof(*mod->trace_events),
                                         &mod->num_trace_events);
+       /*
+        * This section contains pointers to allocated objects in the trace
+        * code and not scanning it leads to false positives.
+        */
+       kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
+                          mod->num_trace_events, GFP_KERNEL);
 #endif
 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
        /* sechdrs[0].sh_size is always zero */