The following commit has been merged into the core/static_call branch of tip:
Commit-ID: 0db6e3734b130207026df1e78455fa98ca1d6f50
Gitweb: https://git.kernel.org/tip/0db6e3734b130207026df1e78455fa98ca1d6f50
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Tue, 18 Aug 2020 15:57:39 +02:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 01 Sep 2020 09:58:04 +02:00
jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved()
Nothing ensures the module exists while we're iterating
mod->jump_entries in __jump_label_mod_text_reserved(), take a module
reference to ensure the module sticks around.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200818135804.504501338@xxxxxxxxxxxxx
---
kernel/jump_label.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index cdb3ffa..e661c61 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -539,19 +539,25 @@ static void static_key_set_mod(struct static_key *key,
static int __jump_label_mod_text_reserved(void *start, void *end)
{
struct module *mod;
+ int ret;
preempt_disable();
mod = __module_text_address((unsigned long)start);
WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
+ if (!try_module_get(mod))
+ mod = NULL;
preempt_enable();
if (!mod)
return 0;
-
- return __jump_label_text_reserved(mod->jump_entries,
+ ret = __jump_label_text_reserved(mod->jump_entries,
mod->jump_entries + mod->num_jump_entries,
start, end);
+
+ module_put(mod);
+
+ return ret;
}
static void __jump_label_mod_update(struct static_key *key)
|