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| 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 19:55:58 +0200 |
| commit | a36e2aa90576263341b3179d47cfe733be7a8085 (patch) | |
| tree | 98b1c484857ce25f150596626e566e4b71eaeb79 | |
| parent | 68a735eb9a16147a85024c47e6176fe4599b91ef (diff) | |
| download | linux-stable-a36e2aa90576263341b3179d47cfe733be7a8085.tar.gz linux-stable-a36e2aa90576263341b3179d47cfe733be7a8085.tar.bz2 linux-stable-a36e2aa90576263341b3179d47cfe733be7a8085.zip | |
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>
| -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 bf8c8fd72589..7c51f065b212 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -605,6 +605,9 @@ 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; @@ -678,6 +681,9 @@ 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; |