[PATCH] /sys/modules: allow full length section names

I've been using systemtap for some debugging and I noticed that it can't
probe a lot of modules.  Turns out it's kind of silly, the sections section
of /sys/module is limited to 32byte filenames and many of the actual
sections are a a bit longer than that.

[akpm@osdl.org: rewrite to use dymanic allocation]
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/CREDITS b/CREDITS
index 8feb2bb49e3580af0d1decc2ad62f3dfa0d35ab4..66e82466dde8af73c814354d8e4df82398e78e5c 100644 (file)
--- a/CREDITS
+++ b/CREDITS
@@ -2478,7 +2478,8 @@ S: Derbyshire DE4 3RL
 S: United Kingdom
 
 N: Ian S. Nelson
-E: ian.nelson@echostar.com
+E: nelsonis@earthlink.net
+P: 1024D/00D3D983 3EFD 7B86 B888 D7E2 29B6  9E97 576F 1B97 00D3 D983
 D: Minor mmap and ide hacks
 S: 1370 Atlantis Ave.
 S: Lafayette CO, 80026

diff --git a/include/linux/module.h b/include/linux/module.h
index d4486cc2e7fe6cdf822d95543610fddee2835185..2c599175c583c36a0bbd71528640489fceb6c149 100644 (file)
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -232,17 +232,17 @@ enum module_state
 };
 
 /* Similar stuff for section attributes. */
-#define MODULE_SECT_NAME_LEN 32
 struct module_sect_attr
 {
        struct module_attribute mattr;
-       char name[MODULE_SECT_NAME_LEN];
+       char *name;
        unsigned long address;
 };
 
 struct module_sect_attrs
 {
        struct attribute_group grp;
+       int nsections;
        struct module_sect_attr attrs[0];
 };
 

diff --git a/kernel/module.c b/kernel/module.c
index b7fe6e84096303865f20e1c606c6bb35c77451c8..05625d5dc7583ac5567d3deec22ebd95c57b72bc 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -933,6 +933,15 @@ static ssize_t module_sect_show(struct module_attribute *mattr,
        return sprintf(buf, "0x%lx\n", sattr->address);
 }
 
+static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
+{
+       int section;
+
+       for (section = 0; section < sect_attrs->nsections; section++)
+               kfree(sect_attrs->attrs[section].name);
+       kfree(sect_attrs);
+}
+
 static void add_sect_attrs(struct module *mod, unsigned int nsect,
                char *secstrings, Elf_Shdr *sechdrs)
 {
@@ -949,21 +958,26 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect,
                        + nloaded * sizeof(sect_attrs->attrs[0]),
                        sizeof(sect_attrs->grp.attrs[0]));
        size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
-       if (! (sect_attrs = kmalloc(size[0] + size[1], GFP_KERNEL)))
+       sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
+       if (sect_attrs == NULL)
                return;
 
        /* Setup section attributes. */
        sect_attrs->grp.name = "sections";
        sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
 
+       sect_attrs->nsections = 0;
        sattr = &sect_attrs->attrs[0];
        gattr = &sect_attrs->grp.attrs[0];
        for (i = 0; i < nsect; i++) {
                if (! (sechdrs[i].sh_flags & SHF_ALLOC))
                        continue;
                sattr->address = sechdrs[i].sh_addr;
-               strlcpy(sattr->name, secstrings + sechdrs[i].sh_name,
-                       MODULE_SECT_NAME_LEN);
+               sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
+                                       GFP_KERNEL);
+               if (sattr->name == NULL)
+                       goto out;
+               sect_attrs->nsections++;
                sattr->mattr.show = module_sect_show;
                sattr->mattr.store = NULL;
                sattr->mattr.attr.name = sattr->name;
@@ -979,7 +993,7 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect,
        mod->sect_attrs = sect_attrs;
        return;
   out:
-       kfree(sect_attrs);
+       free_sect_attrs(sect_attrs);
 }
 
 static void remove_sect_attrs(struct module *mod)
@@ -989,13 +1003,13 @@ static void remove_sect_attrs(struct module *mod)
                                   &mod->sect_attrs->grp);
                /* We are positive that no one is using any sect attrs
                 * at this point.  Deallocate immediately. */
-               kfree(mod->sect_attrs);
+               free_sect_attrs(mod->sect_attrs);
                mod->sect_attrs = NULL;
        }
 }
 
-
 #else
+
 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
                char *sectstrings, Elf_Shdr *sechdrs)
 {