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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/x86/kernel/hw_breakpoint.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/x86/kernel/hw_breakpoint.c')
-rw-r--r--kernel/arch/x86/kernel/hw_breakpoint.c31
1 files changed, 30 insertions, 1 deletions
diff --git a/kernel/arch/x86/kernel/hw_breakpoint.c b/kernel/arch/x86/kernel/hw_breakpoint.c
index 7114ba220..50a3fad5b 100644
--- a/kernel/arch/x86/kernel/hw_breakpoint.c
+++ b/kernel/arch/x86/kernel/hw_breakpoint.c
@@ -32,6 +32,7 @@
#include <linux/irqflags.h>
#include <linux/notifier.h>
#include <linux/kallsyms.h>
+#include <linux/kprobes.h>
#include <linux/percpu.h>
#include <linux/kdebug.h>
#include <linux/kernel.h>
@@ -179,7 +180,11 @@ int arch_check_bp_in_kernelspace(struct perf_event *bp)
va = info->address;
len = bp->attr.bp_len;
- return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
+ /*
+ * We don't need to worry about va + len - 1 overflowing:
+ * we already require that va is aligned to a multiple of len.
+ */
+ return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX);
}
int arch_bp_generic_fields(int x86_len, int x86_type,
@@ -243,6 +248,20 @@ static int arch_build_bp_info(struct perf_event *bp)
info->type = X86_BREAKPOINT_RW;
break;
case HW_BREAKPOINT_X:
+ /*
+ * We don't allow kernel breakpoints in places that are not
+ * acceptable for kprobes. On non-kprobes kernels, we don't
+ * allow kernel breakpoints at all.
+ */
+ if (bp->attr.bp_addr >= TASK_SIZE_MAX) {
+#ifdef CONFIG_KPROBES
+ if (within_kprobe_blacklist(bp->attr.bp_addr))
+ return -EINVAL;
+#else
+ return -EINVAL;
+#endif
+ }
+
info->type = X86_BREAKPOINT_EXECUTE;
/*
* x86 inst breakpoints need to have a specific undefined len.
@@ -276,8 +295,18 @@ static int arch_build_bp_info(struct perf_event *bp)
break;
#endif
default:
+ /* AMD range breakpoint */
if (!is_power_of_2(bp->attr.bp_len))
return -EINVAL;
+ if (bp->attr.bp_addr & (bp->attr.bp_len - 1))
+ return -EINVAL;
+ /*
+ * It's impossible to use a range breakpoint to fake out
+ * user vs kernel detection because bp_len - 1 can't
+ * have the high bit set. If we ever allow range instruction
+ * breakpoints, then we'll have to check for kprobe-blacklisted
+ * addresses anywhere in the range.
+ */
if (!cpu_has_bpext)
return -EOPNOTSUPP;
info->mask = bp->attr.bp_len - 1;