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authorDavid S. Miller <davem@davemloft.net>2016-08-18 08:17:32 +0300
committerDavid S. Miller <davem@davemloft.net>2016-08-18 08:17:32 +0300
commit60747ef4d173c2747bf7f0377fb22846cb422195 (patch)
treeea0faf33b952495c47909be1400c475a3f3821b0 /arch/x86/include/asm/thread_info.h
parent484334198f8ce9552e20930fff9408ebf6bcf94d (diff)
parent184ca823481c99dadd7d946e5afd4bb921eab30d (diff)
downloadlinux-60747ef4d173c2747bf7f0377fb22846cb422195.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor overlapping changes for both merge conflicts. Resolution work done by Stephen Rothwell was used as a reference. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/x86/include/asm/thread_info.h')
-rw-r--r--arch/x86/include/asm/thread_info.h47
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index b45ffdda3549..8b7c8d8e0852 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -176,6 +176,50 @@ static inline unsigned long current_stack_pointer(void)
return sp;
}
+/*
+ * Walks up the stack frames to make sure that the specified object is
+ * entirely contained by a single stack frame.
+ *
+ * Returns:
+ * 1 if within a frame
+ * -1 if placed across a frame boundary (or outside stack)
+ * 0 unable to determine (no frame pointers, etc)
+ */
+static inline int arch_within_stack_frames(const void * const stack,
+ const void * const stackend,
+ const void *obj, unsigned long len)
+{
+#if defined(CONFIG_FRAME_POINTER)
+ const void *frame = NULL;
+ const void *oldframe;
+
+ oldframe = __builtin_frame_address(1);
+ if (oldframe)
+ frame = __builtin_frame_address(2);
+ /*
+ * low ----------------------------------------------> high
+ * [saved bp][saved ip][args][local vars][saved bp][saved ip]
+ * ^----------------^
+ * allow copies only within here
+ */
+ while (stack <= frame && frame < stackend) {
+ /*
+ * If obj + len extends past the last frame, this
+ * check won't pass and the next frame will be 0,
+ * causing us to bail out and correctly report
+ * the copy as invalid.
+ */
+ if (obj + len <= frame)
+ return obj >= oldframe + 2 * sizeof(void *) ? 1 : -1;
+ oldframe = frame;
+ frame = *(const void * const *)frame;
+ }
+ return -1;
+#else
+ return 0;
+#endif
+}
+
#else /* !__ASSEMBLY__ */
#ifdef CONFIG_X86_64
@@ -219,6 +263,9 @@ static inline unsigned long current_stack_pointer(void)
* have to worry about atomic accesses.
*/
#define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/
+#ifdef CONFIG_COMPAT
+#define TS_I386_REGS_POKED 0x0004 /* regs poked by 32-bit ptracer */
+#endif
#ifndef __ASSEMBLY__