diff options
author | Michael Ellerman <michael@ellerman.id.au> | 2006-03-27 14:26:26 +1100 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2006-03-28 16:45:23 +1100 |
commit | 5149fa47ec90eb5e79e28f3a7fbcf29421524817 (patch) | |
tree | c22023d68bbe23d273311185e284ead4c45d5edc /fs/proc/proc_devtree.c | |
parent | d0160bf0b3e87032be8e85f80ddd2f18e107b86f (diff) | |
download | op-kernel-dev-5149fa47ec90eb5e79e28f3a7fbcf29421524817.zip op-kernel-dev-5149fa47ec90eb5e79e28f3a7fbcf29421524817.tar.gz |
[PATCH] powerpc: Cope with duplicate node & property names in /proc/device-tree
Various dodgy firmware might give us nodes and/or properties in the device
tree with conflicting names. That's generally ok, except for when we export
the device tree via /proc, so check when we're creating the proc device tree
and munge names accordingly.
Tested on a faked device tree with kexec, would be good if someone with
actual bogus firmware could try it, but just for completeness.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'fs/proc/proc_devtree.c')
-rw-r--r-- | fs/proc/proc_devtree.c | 103 |
1 files changed, 80 insertions, 23 deletions
diff --git a/fs/proc/proc_devtree.c b/fs/proc/proc_devtree.c index 596b4b4..abdf068 100644 --- a/fs/proc/proc_devtree.c +++ b/fs/proc/proc_devtree.c @@ -52,7 +52,8 @@ static int property_read_proc(char *page, char **start, off_t off, * Add a property to a node */ static struct proc_dir_entry * -__proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp) +__proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp, + const char *name) { struct proc_dir_entry *ent; @@ -60,14 +61,14 @@ __proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp) * Unfortunately proc_register puts each new entry * at the beginning of the list. So we rearrange them. */ - ent = create_proc_read_entry(pp->name, - strncmp(pp->name, "security-", 9) + ent = create_proc_read_entry(name, + strncmp(name, "security-", 9) ? S_IRUGO : S_IRUSR, de, property_read_proc, pp); if (ent == NULL) return NULL; - if (!strncmp(pp->name, "security-", 9)) + if (!strncmp(name, "security-", 9)) ent->size = 0; /* don't leak number of password chars */ else ent->size = pp->length; @@ -78,7 +79,7 @@ __proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp) void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop) { - __proc_device_tree_add_prop(pde, prop); + __proc_device_tree_add_prop(pde, prop, prop->name); } void proc_device_tree_remove_prop(struct proc_dir_entry *pde, @@ -106,6 +107,69 @@ void proc_device_tree_update_prop(struct proc_dir_entry *pde, } /* + * Various dodgy firmware might give us nodes and/or properties with + * conflicting names. That's generally ok, except for exporting via /proc, + * so munge names here to ensure they're unique. + */ + +static int duplicate_name(struct proc_dir_entry *de, const char *name) +{ + struct proc_dir_entry *ent; + int found = 0; + + spin_lock(&proc_subdir_lock); + + for (ent = de->subdir; ent != NULL; ent = ent->next) { + if (strcmp(ent->name, name) == 0) { + found = 1; + break; + } + } + + spin_unlock(&proc_subdir_lock); + + return found; +} + +static const char *fixup_name(struct device_node *np, struct proc_dir_entry *de, + const char *name) +{ + char *fixed_name; + int fixup_len = strlen(name) + 2 + 1; /* name + #x + \0 */ + int i = 1, size; + +realloc: + fixed_name = kmalloc(fixup_len, GFP_KERNEL); + if (fixed_name == NULL) { + printk(KERN_ERR "device-tree: Out of memory trying to fixup " + "name \"%s\"\n", name); + return name; + } + +retry: + size = snprintf(fixed_name, fixup_len, "%s#%d", name, i); + size++; /* account for NULL */ + + if (size > fixup_len) { + /* We ran out of space, free and reallocate. */ + kfree(fixed_name); + fixup_len = size; + goto realloc; + } + + if (duplicate_name(de, fixed_name)) { + /* Multiple duplicates. Retry with a different offset. */ + i++; + goto retry; + } + + printk(KERN_WARNING "device-tree: Duplicate name in %s, " + "renamed to \"%s\"\n", np->full_name, fixed_name); + + return fixed_name; +} + +/* * Process a node, adding entries for its children and its properties. */ void proc_device_tree_add_node(struct device_node *np, @@ -118,37 +182,30 @@ void proc_device_tree_add_node(struct device_node *np, set_node_proc_entry(np, de); for (child = NULL; (child = of_get_next_child(np, child));) { + /* Use everything after the last slash, or the full name */ p = strrchr(child->full_name, '/'); if (!p) p = child->full_name; else ++p; + + if (duplicate_name(de, p)) + p = fixup_name(np, de, p); + ent = proc_mkdir(p, de); if (ent == 0) break; proc_device_tree_add_node(child, ent); } of_node_put(child); + for (pp = np->properties; pp != 0; pp = pp->next) { - /* - * Yet another Apple device-tree bogosity: on some machines, - * they have properties & nodes with the same name. Those - * properties are quite unimportant for us though, thus we - * simply "skip" them here, but we do have to check. - */ - spin_lock(&proc_subdir_lock); - for (ent = de->subdir; ent != NULL; ent = ent->next) - if (!strcmp(ent->name, pp->name)) - break; - spin_unlock(&proc_subdir_lock); - if (ent != NULL) { - printk(KERN_WARNING "device-tree: property \"%s\" name" - " conflicts with node in %s\n", pp->name, - np->full_name); - continue; - } + p = pp->name; + + if (duplicate_name(de, p)) + p = fixup_name(np, de, p); - ent = __proc_device_tree_add_prop(de, pp); + ent = __proc_device_tree_add_prop(de, pp, p); if (ent == 0) break; } |