From 61bf12d3304d78ff499245ea995858c3bedb162e Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Thu, 7 Apr 2016 18:06:25 +0200 Subject: [PATCH] livepatch: robustify klp_register_patch() API error checking Commit 425595a7fc20 ("livepatch: reuse module loader code to write relocations") adds a possibility of dereferncing pointers supplied by the consumer of the livepatch API before sanity (NULL) checking them (patch and patch->mod). Spotted by smatch tool. Reported-by: Dan Carpenter Acked-by: Josh Poimboeuf Acked-by: Jessica Yu Signed-off-by: Jiri Kosina --- kernel/livepatch/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index eb5db6e837aa..28c37fa3d3f9 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -876,6 +876,9 @@ int klp_register_patch(struct klp_patch *patch) { int ret; + if (!patch || !patch->mod) + return -EINVAL; + if (!is_livepatch_module(patch->mod)) { pr_err("module %s is not marked as a livepatch module", patch->mod->name); @@ -885,9 +888,6 @@ int klp_register_patch(struct klp_patch *patch) if (!klp_initialized()) return -ENODEV; - if (!patch || !patch->mod) - return -EINVAL; - /* * A reference is taken on the patch module to prevent it from being * unloaded. Right now, we don't allow patch modules to unload since