From db3516bbfabe710a0292f642cb83b95ea24c323a Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Mon, 16 Nov 2015 15:37:03 +0000 Subject: [PATCH] Fix stack buffer overflow in aarch64_extract_return_value Hi, I build GDB with -fsanitize=address, and run testsuite. In gdb.base/callfuncs.exp, I see the following error, p/c fun1() =================================================================^M ==9601==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffee858530 at pc 0x6df079 bp 0x7fffee8583a0 sp 0x7fffee858398 WRITE of size 16 at 0x7fffee858530 thread T0 #0 0x6df078 in regcache_raw_read /home/yao/SourceCode/gnu/gdb/git/gdb/regcache.c:673 #1 0x6dfe1e in regcache_cooked_read /home/yao/SourceCode/gnu/gdb/git/gdb/regcache.c:751 #2 0x4696a3 in aarch64_extract_return_value /home/yao/SourceCode/gnu/gdb/git/gdb/aarch64-tdep.c:1708 #3 0x46ae57 in aarch64_return_value /home/yao/SourceCode/gnu/gdb/git/gdb/aarch64-tdep.c:1918 We are extracting return value from V registers (128 bit), but only allocate X_REGISTER_SIZE-byte array, which isn't sufficient. This patch changes the array to V_REGISTER_SIZE. gdb: 2015-11-16 Yao Qi * aarch64-tdep.c (aarch64_extract_return_value): Change array buf's length to V_REGISTER_SIZE. --- gdb/ChangeLog | 5 +++++ gdb/aarch64-tdep.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 30ae510a63b..fd2ac45cac7 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2015-11-16 Yao Qi + + * aarch64-tdep.c (aarch64_extract_return_value): Change array + buf's length to V_REGISTER_SIZE. + 2015-11-16 Yao Qi * aarch64-tdep.c (pass_in_x_or_stack): Change argument type diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c index b025ebaf722..de045e604bd 100644 --- a/gdb/aarch64-tdep.c +++ b/gdb/aarch64-tdep.c @@ -1620,7 +1620,7 @@ aarch64_extract_return_value (struct type *type, struct regcache *regs, for (i = 0; i < elements; i++) { int regno = AARCH64_V0_REGNUM + i; - bfd_byte buf[X_REGISTER_SIZE]; + bfd_byte buf[V_REGISTER_SIZE]; if (aarch64_debug) { -- 2.30.2