From: Steven Rostedt (VMware) Date: Thu, 23 Apr 2020 01:38:45 +0000 (-0400) Subject: ftrace: Fix memory leak caused by not freeing entry in unregister_ftrace_direct() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=353da87921a5ec654e7e9024e083f099f1b33c97;p=linux.git ftrace: Fix memory leak caused by not freeing entry in unregister_ftrace_direct() kmemleak reported the following: unreferenced object 0xffff90d47127a920 (size 32): comm "modprobe", pid 1766, jiffies 4294792031 (age 162.568s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 22 01 00 00 00 00 ad de ........"....... 00 78 12 a7 ff ff ff ff 00 00 b6 c0 ff ff ff ff .x.............. backtrace: [<00000000bb79e72e>] register_ftrace_direct+0xcb/0x3a0 [<00000000295e4f79>] do_one_initcall+0x72/0x340 [<00000000873ead18>] do_init_module+0x5a/0x220 [<00000000974d9de5>] load_module+0x2235/0x2550 [<0000000059c3d6ce>] __do_sys_finit_module+0xc0/0x120 [<000000005a8611b4>] do_syscall_64+0x60/0x230 [<00000000a0cdc49e>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 The entry used to save the direct descriptor needs to be freed when unregistering. Signed-off-by: Steven Rostedt (VMware) --- diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 041694a1eb74d..bd030b1b95148 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5165,6 +5165,7 @@ int unregister_ftrace_direct(unsigned long ip, unsigned long addr) list_del_rcu(&direct->next); synchronize_rcu_tasks(); kfree(direct); + kfree(entry); ftrace_direct_func_count--; } }