Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.9 057/104] lkdtm: Fix Oops when unloading the module | Date | Fri, 6 Oct 2017 10:51:35 +0200 |
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4.9-stable review patch. If anyone has any objections, please let me know.
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From: Juerg Haefliger <juerg.haefliger@hpe.com>
[ Upstream commit 9ba60573638e2006170ebcc5489fb1e068afbc8f ]
No jprobe is registered when the module is loaded without specifying a crashpoint that uses a jprobe. At the moment, we unconditionally try to unregister the jprobe on module unload which results in an Oops. Add a check to fix this.
Signed-off-by: Juerg Haefliger <juerg.haefliger@hpe.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/misc/lkdtm_core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/misc/lkdtm_core.c +++ b/drivers/misc/lkdtm_core.c @@ -533,7 +533,9 @@ static void __exit lkdtm_module_exit(voi /* Handle test-specific clean-up. */ lkdtm_usercopy_exit(); - unregister_jprobe(lkdtm_jprobe); + if (lkdtm_jprobe != NULL) + unregister_jprobe(lkdtm_jprobe); + pr_info("Crash point unregistered\n"); }
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