4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
commit ce01a1575f45bf319e374592656441021a7f5823 upstream.
On x86-64, the parametrized selftest code for rseq crashes with a
segmentation fault when compiled with -fpie. This happens when the
param_test binary is loaded at an address beyond 32-bit on x86-64.
The issue is caused by use of a 32-bit register to hold the address
of the loop counter variable.
Fix this by using a 64-bit register to calculate the address of the
loop counter variables as an offset from rip.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Acked-by: "Paul E . McKenney" <paul...@linux.vnet.ibm.com>
Cc: <sta...@vger.kernel.org> # v4.18
Cc: Shuah Khan <sh...@kernel.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Joel Fernandes <joe...@google.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: Dave Watson <davejwat...@fb.com>
Cc: Will Deacon <will.dea...@arm.com>
Cc: Andi Kleen <a...@firstfloor.org>
Cc: linux-kselft...@vger.kernel.org
Cc: "H . Peter Anvin" <h...@zytor.com>
Cc: Chris Lameter <c...@linux.com>
Cc: Russell King <li...@arm.linux.org.uk>
Cc: Michael Kerrisk <mtk.manpa...@gmail.com>
Cc: "Paul E . McKenney" <paul...@linux.vnet.ibm.com>
Cc: Paul Turner <p...@google.com>
Cc: Boqun Feng <boqun.f...@gmail.com>
Cc: Josh Triplett <j...@joshtriplett.org>
Cc: Steven Rostedt <rost...@goodmis.org>
Cc: Ben Maurer <bmau...@fb.com>
Cc: Andy Lutomirski <l...@amacapital.net>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Signed-off-by: Shuah Khan (Samsung OSG) <sh...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
tools/testing/selftests/rseq/param_test.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
--- a/tools/testing/selftests/rseq/param_test.c
+++ b/tools/testing/selftests/rseq/param_test.c
@@ -56,15 +56,13 @@ unsigned int yield_mod_cnt, nr_abort;
printf(fmt, ## __VA_ARGS__); \
} while (0)
-#if defined(__x86_64__) || defined(__i386__)
+#ifdef __i386__
#define INJECT_ASM_REG "eax"
#define RSEQ_INJECT_CLOBBER \
, INJECT_ASM_REG
-#ifdef __i386__
-
#define RSEQ_INJECT_ASM(n) \
"mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \
"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
@@ -76,9 +74,16 @@ unsigned int yield_mod_cnt, nr_abort;
#elif defined(__x86_64__)
+#define INJECT_ASM_REG_P "rax"
+#define INJECT_ASM_REG "eax"
+
+#define RSEQ_INJECT_CLOBBER \
+ , INJECT_ASM_REG_P \
+ , INJECT_ASM_REG
+
#define RSEQ_INJECT_ASM(n) \
- "lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG "\n\t" \
- "mov (%%" INJECT_ASM_REG "), %%" INJECT_ASM_REG "\n\t" \
+ "lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG_P "\n\t" \
+ "mov (%%" INJECT_ASM_REG_P "), %%" INJECT_ASM_REG "\n\t" \
"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
"jz 333f\n\t" \
"222:\n\t" \
@@ -86,10 +91,6 @@ unsigned int yield_mod_cnt, nr_abort;
"jnz 222b\n\t" \
"333:\n\t"
-#else
-#error "Unsupported architecture"
-#endif
-
#elif defined(__ARMEL__)
#define RSEQ_INJECT_INPUT \
