module: refactor load_module
I'd start from the trivial stuff. There's a fair amount of straight-line
code that just makes the function hard to read just because you have to
page up and down so far. Some of it is trivial to just create a helper
function for.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/kernel/module.c b/kernel/module.c
index 404e722..12905ed 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2107,6 +2107,71 @@
}
#endif
+static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
+ Elf_Shdr *sechdrs, const char *secstrings)
+{
+ mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
+ sizeof(*mod->kp), &mod->num_kp);
+ mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
+ sizeof(*mod->syms), &mod->num_syms);
+ mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
+ mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
+ sizeof(*mod->gpl_syms),
+ &mod->num_gpl_syms);
+ mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
+ mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
+ "__ksymtab_gpl_future",
+ sizeof(*mod->gpl_future_syms),
+ &mod->num_gpl_future_syms);
+ mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
+ "__kcrctab_gpl_future");
+
+#ifdef CONFIG_UNUSED_SYMBOLS
+ mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
+ "__ksymtab_unused",
+ sizeof(*mod->unused_syms),
+ &mod->num_unused_syms);
+ mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
+ "__kcrctab_unused");
+ mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
+ "__ksymtab_unused_gpl",
+ sizeof(*mod->unused_gpl_syms),
+ &mod->num_unused_gpl_syms);
+ mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
+ "__kcrctab_unused_gpl");
+#endif
+#ifdef CONFIG_CONSTRUCTORS
+ mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
+ sizeof(*mod->ctors), &mod->num_ctors);
+#endif
+
+#ifdef CONFIG_TRACEPOINTS
+ mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
+ "__tracepoints",
+ sizeof(*mod->tracepoints),
+ &mod->num_tracepoints);
+#endif
+#ifdef CONFIG_EVENT_TRACING
+ mod->trace_events = section_objs(hdr, sechdrs, secstrings,
+ "_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 */
+ mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
+ "__mcount_loc",
+ sizeof(*mod->ftrace_callsites),
+ &mod->num_ftrace_callsites);
+#endif
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static noinline struct module *load_module(void __user *umod,
@@ -2147,7 +2212,7 @@
}
/* Sanity checks against insmoding binaries or wrong arch,
- weird elf version */
+ weird elf version */
if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
|| hdr->e_type != ET_REL
|| !elf_check_arch(hdr)
@@ -2326,7 +2391,8 @@
sechdrs[i].sh_size);
/* Update sh_addr to point to copy in image. */
sechdrs[i].sh_addr = (unsigned long)dest;
- DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
+ DEBUGP("\t0x%lx %s\n",
+ sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
}
/* Module has been moved. */
mod = (void *)sechdrs[modindex].sh_addr;
@@ -2368,66 +2434,8 @@
/* Now we've got everything in the final locations, we can
* find optional sections. */
- mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
- sizeof(*mod->kp), &mod->num_kp);
- mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
- sizeof(*mod->syms), &mod->num_syms);
- mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
- mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
- sizeof(*mod->gpl_syms),
- &mod->num_gpl_syms);
- mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
- mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
- "__ksymtab_gpl_future",
- sizeof(*mod->gpl_future_syms),
- &mod->num_gpl_future_syms);
- mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
- "__kcrctab_gpl_future");
+ find_module_sections(mod, hdr, sechdrs, secstrings);
-#ifdef CONFIG_UNUSED_SYMBOLS
- mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
- "__ksymtab_unused",
- sizeof(*mod->unused_syms),
- &mod->num_unused_syms);
- mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
- "__kcrctab_unused");
- mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
- "__ksymtab_unused_gpl",
- sizeof(*mod->unused_gpl_syms),
- &mod->num_unused_gpl_syms);
- mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
- "__kcrctab_unused_gpl");
-#endif
-#ifdef CONFIG_CONSTRUCTORS
- mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
- sizeof(*mod->ctors), &mod->num_ctors);
-#endif
-
-#ifdef CONFIG_TRACEPOINTS
- mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
- "__tracepoints",
- sizeof(*mod->tracepoints),
- &mod->num_tracepoints);
-#endif
-#ifdef CONFIG_EVENT_TRACING
- mod->trace_events = section_objs(hdr, sechdrs, secstrings,
- "_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 */
- mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
- "__mcount_loc",
- sizeof(*mod->ftrace_callsites),
- &mod->num_ftrace_callsites);
-#endif
#ifdef CONFIG_MODVERSIONS
if ((mod->num_syms && !mod->crcs)
|| (mod->num_gpl_syms && !mod->gpl_crcs)