summaryrefslogtreecommitdiffstats
path: root/kernel/kprobes.c
diff options
context:
space:
mode:
authorJason Baron <jbaron@redhat.com>2010-10-01 17:23:41 -0400
committerSteven Rostedt <rostedt@goodmis.org>2010-10-28 09:17:02 -0400
commitb842f8faf6c7dc2005c6a70631c1a91bac02f180 (patch)
treefa4c5ed7136be2e39b728173fcae2385b119bcef /kernel/kprobes.c
parente3e1288e86a07cdeb0aee5860a2dff111c6eff79 (diff)
downloadlinux-b842f8faf6c7dc2005c6a70631c1a91bac02f180.tar.gz
linux-b842f8faf6c7dc2005c6a70631c1a91bac02f180.tar.bz2
linux-b842f8faf6c7dc2005c6a70631c1a91bac02f180.zip
jump label: Fix module __init section race
Jump label uses is_module_text_address() to ensure that the module __init sections are valid before updating them. However, between the check for a valid module __init section and the subsequent jump label update, the module's __init section could be freed out from under us. We fix this potential race by adding a notifier callback to the MODULE_STATE_LIVE state. This notifier is called *after* the __init section has been run but before it is going to be freed. In the callback, the jump label code zeros the key value for any __init jump code within the module, and we add a check for a non-zero key value when we update jump labels. In this way we require no additional data structures. Thanks to Mathieu Desnoyers for pointing out this race condition. Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <c6f037b7598777668025ceedd9294212fd95fa34.1285965957.git.jbaron@redhat.com> [ Renamed remove_module_init() to remove_jump_label_module_init() as suggested by Masami Hiramatsu. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/kprobes.c')
0 files changed, 0 insertions, 0 deletions