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authorChris Metcalf <cmetcalf@tilera.com>2014-09-05 14:40:23 -0400
committerChris Metcalf <cmetcalf@tilera.com>2014-09-06 12:24:03 -0400
commit8622092d584962801e4248cd4bb4bef6e71827b0 (patch)
tree59a1913ca848fa3818327716497d4355afb667fa /sysdeps/tile
parent41488498b6d9440ee66ab033808cce8323bba7ac (diff)
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[BZ #17354] tile: Fix up corner cases with signed relocations
Some types of relocations technically need to be signed rather than unsigned: in particular ones that are used with moveli or movei, or for jump and branch. This is almost never a problem. Jump and branch opcodes are pretty much uniformly resolved by the static linker (unless you omit -fpic for a shared library, which is not recommended). The moveli and movei opcodes that need to be sign-extended generally are for positive displacements, like the construction of the address of main() from _start(). However, tst-pie1 ends up with main below _start (in a different module) and the test failed due to signedness issues in relocation handling. This commit treats the value as signed when shifting (to preserve the high bit) and also sign-extends the value generated from the updated bundle when comparing with the desired bundle, which we do to make sure no overflow occurred. As a result, the tst-pie1 test now passes.
Diffstat (limited to 'sysdeps/tile')
-rw-r--r--sysdeps/tile/dl-machine.h41
1 files changed, 23 insertions, 18 deletions
diff --git a/sysdeps/tile/dl-machine.h b/sysdeps/tile/dl-machine.h
index 8be6758..a96f23f 100644
--- a/sysdeps/tile/dl-machine.h
+++ b/sysdeps/tile/dl-machine.h
@@ -657,7 +657,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
value += 0x8000;
#endif
- value >>= h->right_shift;
+ value = ((long) value) >> h->right_shift;
switch (h->byte_size)
{
@@ -686,13 +686,18 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
tile_bundle_bits *p = (tile_bundle_bits *) reloc_addr;
tile_bundle_bits bits = *p;
-#define MUNGE(func) do { \
+#define MUNGE_SIGNED(func, length) do { \
bits = ((bits & ~create_##func (-1)) | create_##func (value)); \
- if (get_##func (bits) != value) \
+ ElfW(Addr) result = get_##func (bits); \
+ int signbits = __WORDSIZE - length; \
+ result = (long) (result << signbits) >> signbits; \
+ if (result != value) \
_dl_signal_error (0, map->l_name, NULL, \
"relocation value too large for " #func); \
} while (0)
+#define MUNGE(func) MUNGE_SIGNED(func, __WORDSIZE)
+
#define MUNGE_NOCHECK(func) \
bits = ((bits & ~create_##func (-1)) | create_##func (value))
@@ -700,23 +705,23 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
{
#ifdef __tilegx__
case R_TILEGX_BROFF_X1:
- MUNGE (BrOff_X1);
+ MUNGE_SIGNED (BrOff_X1, 17);
break;
case R_TILEGX_JUMPOFF_X1:
case R_TILEGX_JUMPOFF_X1_PLT:
- MUNGE (JumpOff_X1);
+ MUNGE_SIGNED (JumpOff_X1, 27);
break;
case R_TILEGX_IMM8_X0:
- MUNGE (Imm8_X0);
+ MUNGE_SIGNED (Imm8_X0, 8);
break;
case R_TILEGX_IMM8_Y0:
- MUNGE (Imm8_Y0);
+ MUNGE_SIGNED (Imm8_Y0, 8);
break;
case R_TILEGX_IMM8_X1:
- MUNGE (Imm8_X1);
+ MUNGE_SIGNED (Imm8_X1, 8);
break;
case R_TILEGX_IMM8_Y1:
- MUNGE (Imm8_Y1);
+ MUNGE_SIGNED (Imm8_Y1, 8);
break;
case R_TILEGX_MT_IMM14_X1:
MUNGE (MT_Imm14_X1);
@@ -746,7 +751,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
case R_TILEGX_IMM16_X0_HW1_LAST_TLS_GD:
case R_TILEGX_IMM16_X0_HW0_LAST_TLS_IE:
case R_TILEGX_IMM16_X0_HW1_LAST_TLS_IE:
- MUNGE (Imm16_X0);
+ MUNGE_SIGNED (Imm16_X0, 16);
break;
case R_TILEGX_IMM16_X1_HW0:
case R_TILEGX_IMM16_X1_HW1:
@@ -770,7 +775,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
case R_TILEGX_IMM16_X1_HW1_LAST_TLS_GD:
case R_TILEGX_IMM16_X1_HW0_LAST_TLS_IE:
case R_TILEGX_IMM16_X1_HW1_LAST_TLS_IE:
- MUNGE (Imm16_X1);
+ MUNGE_SIGNED (Imm16_X1, 16);
break;
case R_TILEGX_MMSTART_X0:
MUNGE (BFStart_X0);
@@ -792,23 +797,23 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
break;
#else
case R_TILEPRO_BROFF_X1:
- MUNGE (BrOff_X1);
+ MUNGE_SIGNED (BrOff_X1, 17);
break;
case R_TILEPRO_JOFFLONG_X1:
case R_TILEPRO_JOFFLONG_X1_PLT:
MUNGE_NOCHECK (JOffLong_X1); /* holds full 32-bit value */
break;
case R_TILEPRO_IMM8_X0:
- MUNGE (Imm8_X0);
+ MUNGE_SIGNED (Imm8_X0, 8);
break;
case R_TILEPRO_IMM8_Y0:
- MUNGE (Imm8_Y0);
+ MUNGE_SIGNED (Imm8_Y0, 8);
break;
case R_TILEPRO_IMM8_X1:
- MUNGE (Imm8_X1);
+ MUNGE_SIGNED (Imm8_X1, 8);
break;
case R_TILEPRO_IMM8_Y1:
- MUNGE (Imm8_Y1);
+ MUNGE_SIGNED (Imm8_Y1, 8);
break;
case R_TILEPRO_MT_IMM15_X1:
MUNGE (MT_Imm15_X1);
@@ -834,7 +839,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
case R_TILEPRO_IMM16_X0_PCREL:
case R_TILEPRO_IMM16_X0_TLS_GD:
case R_TILEPRO_IMM16_X0_TLS_IE:
- MUNGE (Imm16_X0);
+ MUNGE_SIGNED (Imm16_X0, 16);
break;
case R_TILEPRO_IMM16_X1_LO:
case R_TILEPRO_IMM16_X1_HI:
@@ -854,7 +859,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
case R_TILEPRO_IMM16_X1_PCREL:
case R_TILEPRO_IMM16_X1_TLS_GD:
case R_TILEPRO_IMM16_X1_TLS_IE:
- MUNGE (Imm16_X1);
+ MUNGE_SIGNED (Imm16_X1, 16);
break;
case R_TILEPRO_MMSTART_X0:
MUNGE (MMStart_X0);