Messages in this thread Patch in this message | | | From | "Aneesh Kumar K.V" <> | Subject | [PATCH V2 09/10] kasan: Prevent deadlock in kasan reporting | Date | Wed, 26 Aug 2015 13:56:17 +0530 |
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We we end up calling kasan_report in real mode, our shadow mapping for even spinlock variable will show poisoned. This will result in us calling kasan_report_error with lock_report spin lock held. To prevent this disable kasan reporting when we are priting error w.r.t kasan.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> --- mm/kasan/report.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 79fbc5d14bd2..82b41eb83e43 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -185,6 +185,10 @@ void kasan_report_error(struct kasan_access_info *info) { unsigned long flags; + /* + * Make sure we don't end up in loop. + */ + kasan_disable_current(); spin_lock_irqsave(&report_lock, flags); pr_err("=================================" "=================================\n"); @@ -194,12 +198,17 @@ void kasan_report_error(struct kasan_access_info *info) pr_err("=================================" "=================================\n"); spin_unlock_irqrestore(&report_lock, flags); + kasan_enable_current(); } void kasan_report_user_access(struct kasan_access_info *info) { unsigned long flags; + /* + * Make sure we don't end up in loop. + */ + kasan_disable_current(); spin_lock_irqsave(&report_lock, flags); pr_err("=================================" "=================================\n"); @@ -212,6 +221,7 @@ void kasan_report_user_access(struct kasan_access_info *info) pr_err("=================================" "=================================\n"); spin_unlock_irqrestore(&report_lock, flags); + kasan_enable_current(); } void kasan_report(unsigned long addr, size_t size, -- 2.5.0
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