diff options
author | Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> | 2018-07-20 15:16:42 +0530 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-09 10:32:35 +0200 |
commit | ee20433f60ae34b52fb11e8f70a8f6139252eb68 (patch) | |
tree | f1beb0c683aa9310deeb218bf2a7da74173e1478 /kernel | |
parent | 640d29c1236e3222a47b0a5460f6f24c2781c700 (diff) |
livepatch: Validate module/old func name length
commit 6e9df95b76cad18f7b217bdad7bb8a26d63b8c47 upstream.
livepatch module author can pass module name/old function name with more
than the defined character limit. With obj->name length greater than
MODULE_NAME_LEN, the livepatch module gets loaded but waits forever on
the module specified by obj->name to be loaded. It also populates a /sys
directory with an untruncated object name.
In the case of funcs->old_name length greater then KSYM_NAME_LEN, it
would not match against any of the symbol table entries. Instead loop
through the symbol table comparing them against a nonexisting function,
which can be avoided.
The same issues apply, to misspelled/incorrect names. At least gatekeep
the modules with over the limit string length, by checking for their
length during livepatch module registration.
Cc: stable@vger.kernel.org
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/livepatch/core.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 3a4656fb7047..5b77a7314e01 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -678,6 +678,9 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func) if (!func->old_name || !func->new_func) return -EINVAL; + if (strlen(func->old_name) >= KSYM_NAME_LEN) + return -EINVAL; + INIT_LIST_HEAD(&func->stack_node); func->patched = false; func->transition = false; @@ -751,6 +754,9 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj) if (!obj->funcs) return -EINVAL; + if (klp_is_module(obj) && strlen(obj->name) >= MODULE_NAME_LEN) + return -EINVAL; + obj->patched = false; obj->mod = NULL; |