From 308c2095da305f6fee76686616f5b35ecacfeb3b Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 7 May 2020 13:08:44 -0700 Subject: [PATCH] kgdb: Prevent infinite recursive entries to the debugger [ Upstream commit 3ca676e4ca60d1834bb77535dafe24169cadacef ] If we detect that we recursively entered the debugger we should hack our I/O ops to NULL so that the panic() in the next line won't actually cause another recursion into the debugger. The first line of kgdb_panic() will check this and return. Signed-off-by: Douglas Anderson Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20200507130644.v4.6.I89de39f68736c9de610e6f241e68d8dbc44bc266@changeid Signed-off-by: Daniel Thompson Signed-off-by: Sasha Levin --- kernel/debug/debug_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index d0d557c0ceff..7d54c7c28054 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -501,6 +501,7 @@ static int kgdb_reenter_check(struct kgdb_state *ks) if (exception_level > 1) { dump_stack(); + kgdb_io_module_registered = false; panic("Recursive entry to debugger"); }