| |
| /*--------------------------------------------------------------------*/ |
| /*--- Maintain bitmaps of memory, tracking the accessibility (A) ---*/ |
| /*--- and validity (V) status of each byte. ---*/ |
| /*--- vg_memory.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, an x86 protected-mode emulator |
| designed for debugging and profiling binaries on x86-Unixes. |
| |
| Copyright (C) 2000-2002 Julian Seward |
| jseward@acm.org |
| |
| This program is free software; you can redistribute it and/or |
| modify it under the terms of the GNU General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307, USA. |
| |
| The GNU General Public License is contained in the file LICENSE. |
| */ |
| |
| #include "vg_include.h" |
| |
| /* Define to debug the mem audit system. */ |
| /* #define VG_DEBUG_MEMORY */ |
| |
| /* Define to debug the memory-leak-detector. */ |
| /* #define VG_DEBUG_LEAKCHECK */ |
| |
| /* Define to collect detailed performance info. */ |
| /* #define VG_PROFILE_MEMORY */ |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Low-level support for memory checking. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* |
| All reads and writes are checked against a memory map, which |
| records the state of all memory in the process. The memory map is |
| organised like this: |
| |
| The top 16 bits of an address are used to index into a top-level |
| map table, containing 65536 entries. Each entry is a pointer to a |
| second-level map, which records the accesibililty and validity |
| permissions for the 65536 bytes indexed by the lower 16 bits of the |
| address. Each byte is represented by nine bits, one indicating |
| accessibility, the other eight validity. So each second-level map |
| contains 73728 bytes. This two-level arrangement conveniently |
| divides the 4G address space into 64k lumps, each size 64k bytes. |
| |
| All entries in the primary (top-level) map must point to a valid |
| secondary (second-level) map. Since most of the 4G of address |
| space will not be in use -- ie, not mapped at all -- there is a |
| distinguished secondary map, which indicates `not addressible and |
| not valid' writeable for all bytes. Entries in the primary map for |
| which the entire 64k is not in use at all point at this |
| distinguished map. |
| |
| [...] lots of stuff deleted due to out of date-ness |
| |
| As a final optimisation, the alignment and address checks for |
| 4-byte loads and stores are combined in a neat way. The primary |
| map is extended to have 262144 entries (2^18), rather than 2^16. |
| The top 3/4 of these entries are permanently set to the |
| distinguished secondary map. For a 4-byte load/store, the |
| top-level map is indexed not with (addr >> 16) but instead f(addr), |
| where |
| |
| f( XXXX XXXX XXXX XXXX ____ ____ ____ __YZ ) |
| = ____ ____ ____ __YZ XXXX XXXX XXXX XXXX or |
| = ____ ____ ____ __ZY XXXX XXXX XXXX XXXX |
| |
| ie the lowest two bits are placed above the 16 high address bits. |
| If either of these two bits are nonzero, the address is misaligned; |
| this will select a secondary map from the upper 3/4 of the primary |
| map. Because this is always the distinguished secondary map, a |
| (bogus) address check failure will result. The failure handling |
| code can then figure out whether this is a genuine addr check |
| failure or whether it is a possibly-legitimate access at a |
| misaligned address. |
| */ |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Crude profiling machinery. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| #ifdef VG_PROFILE_MEMORY |
| |
| #define N_PROF_EVENTS 120 |
| |
| static UInt event_ctr[N_PROF_EVENTS]; |
| |
| static void init_prof_mem ( void ) |
| { |
| Int i; |
| for (i = 0; i < N_PROF_EVENTS; i++) |
| event_ctr[i] = 0; |
| } |
| |
| void VG_(done_prof_mem) ( void ) |
| { |
| Int i; |
| for (i = 0; i < N_PROF_EVENTS; i++) { |
| if ((i % 10) == 0) |
| VG_(printf)("\n"); |
| if (event_ctr[i] > 0) |
| VG_(printf)( "prof mem event %2d: %d\n", i, event_ctr[i] ); |
| } |
| VG_(printf)("\n"); |
| } |
| |
| #define PROF_EVENT(ev) \ |
| do { vg_assert((ev) >= 0 && (ev) < N_PROF_EVENTS); \ |
| event_ctr[ev]++; \ |
| } while (False); |
| |
| #else |
| |
| static void init_prof_mem ( void ) { } |
| void VG_(done_prof_mem) ( void ) { } |
| |
| #define PROF_EVENT(ev) /* */ |
| |
| #endif |
| |
| /* Event index. If just the name of the fn is given, this means the |
| number of calls to the fn. Otherwise it is the specified event. |
| |
| 10 alloc_secondary_map |
| |
| 20 get_abit |
| 21 get_vbyte |
| 22 set_abit |
| 23 set_vbyte |
| 24 get_abits4_ALIGNED |
| 25 get_vbytes4_ALIGNED |
| |
| 30 set_address_range_perms |
| 31 set_address_range_perms(lower byte loop) |
| 32 set_address_range_perms(quadword loop) |
| 33 set_address_range_perms(upper byte loop) |
| |
| 35 make_noaccess |
| 36 make_writable |
| 37 make_readable |
| |
| 40 copy_address_range_perms |
| 41 copy_address_range_perms(byte loop) |
| 42 check_writable |
| 43 check_writable(byte loop) |
| 44 check_readable |
| 45 check_readable(byte loop) |
| 46 check_readable_asciiz |
| 47 check_readable_asciiz(byte loop) |
| |
| 50 make_aligned_word_NOACCESS |
| 51 make_aligned_word_WRITABLE |
| |
| 60 helperc_LOADV4 |
| 61 helperc_STOREV4 |
| 62 helperc_LOADV2 |
| 63 helperc_STOREV2 |
| 64 helperc_LOADV1 |
| 65 helperc_STOREV1 |
| |
| 70 rim_rd_V4_SLOWLY |
| 71 rim_wr_V4_SLOWLY |
| 72 rim_rd_V2_SLOWLY |
| 73 rim_wr_V2_SLOWLY |
| 74 rim_rd_V1_SLOWLY |
| 75 rim_wr_V1_SLOWLY |
| |
| 80 fpu_read |
| 81 fpu_read aligned 4 |
| 82 fpu_read aligned 8 |
| 83 fpu_read 2 |
| 84 fpu_read 10 |
| |
| 85 fpu_write |
| 86 fpu_write aligned 4 |
| 87 fpu_write aligned 8 |
| 88 fpu_write 2 |
| 89 fpu_write 10 |
| |
| 90 fpu_read_check_SLOWLY |
| 91 fpu_read_check_SLOWLY(byte loop) |
| 92 fpu_write_check_SLOWLY |
| 93 fpu_write_check_SLOWLY(byte loop) |
| |
| 100 is_plausible_stack_addr |
| 101 handle_esp_assignment |
| 102 handle_esp_assignment(-4) |
| 103 handle_esp_assignment(+4) |
| 104 handle_esp_assignment(+16) |
| 105 handle_esp_assignment(-12) |
| 106 handle_esp_assignment(+8) |
| 107 handle_esp_assignment(-8) |
| |
| 110 vg_handle_esp_assignment_SLOWLY |
| 111 vg_handle_esp_assignment_SLOWLY(normal; move down) |
| 112 vg_handle_esp_assignment_SLOWLY(normal; move up) |
| 113 vg_handle_esp_assignment_SLOWLY(normal) |
| 114 vg_handle_esp_assignment_SLOWLY(>= HUGE_DELTA) |
| */ |
| |
| /*------------------------------------------------------------*/ |
| /*--- Function declarations. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Set permissions for an address range. Not speed-critical. */ |
| void VGM_(make_noaccess) ( Addr a, UInt len ); |
| void VGM_(make_writable) ( Addr a, UInt len ); |
| void VGM_(make_readable) ( Addr a, UInt len ); |
| |
| /* Check permissions for an address range. Not speed-critical. */ |
| Bool VGM_(check_writable) ( Addr a, UInt len, Addr* bad_addr ); |
| Bool VGM_(check_readable) ( Addr a, UInt len, Addr* bad_addr ); |
| Bool VGM_(check_readable_asciiz) ( Addr a, Addr* bad_addr ); |
| |
| static UInt vgm_rd_V4_SLOWLY ( Addr a ); |
| static UInt vgm_rd_V2_SLOWLY ( Addr a ); |
| static UInt vgm_rd_V1_SLOWLY ( Addr a ); |
| static void vgm_wr_V4_SLOWLY ( Addr a, UInt vbytes ); |
| static void vgm_wr_V2_SLOWLY ( Addr a, UInt vbytes ); |
| static void vgm_wr_V1_SLOWLY ( Addr a, UInt vbytes ); |
| static void fpu_read_check_SLOWLY ( Addr addr, Int size ); |
| static void fpu_write_check_SLOWLY ( Addr addr, Int size ); |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Data defns. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| typedef |
| struct { |
| UChar abits[8192]; |
| UChar vbyte[65536]; |
| } |
| SecMap; |
| |
| /* These two are statically allocated. Should they be non-public? */ |
| SecMap* VG_(primary_map)[ /*65536*/ 262144 ]; |
| static SecMap vg_distinguished_secondary_map; |
| |
| #define IS_DISTINGUISHED_SM(smap) \ |
| ((smap) == &vg_distinguished_secondary_map) |
| |
| #define ENSURE_MAPPABLE(addr,caller) \ |
| do { \ |
| if (IS_DISTINGUISHED_SM(VG_(primary_map)[(addr) >> 16])) { \ |
| VG_(primary_map)[(addr) >> 16] = alloc_secondary_map(caller); \ |
| /* VG_(printf)("new 2map because of %p\n", addr); */ \ |
| } \ |
| } while(0) |
| |
| #define BITARR_SET(aaa_p,iii_p) \ |
| do { \ |
| UInt iii = (UInt)iii_p; \ |
| UChar* aaa = (UChar*)aaa_p; \ |
| aaa[iii >> 3] |= (1 << (iii & 7)); \ |
| } while (0) |
| |
| #define BITARR_CLEAR(aaa_p,iii_p) \ |
| do { \ |
| UInt iii = (UInt)iii_p; \ |
| UChar* aaa = (UChar*)aaa_p; \ |
| aaa[iii >> 3] &= ~(1 << (iii & 7)); \ |
| } while (0) |
| |
| #define BITARR_TEST(aaa_p,iii_p) \ |
| (0 != (((UChar*)aaa_p)[ ((UInt)iii_p) >> 3 ] \ |
| & (1 << (((UInt)iii_p) & 7)))) \ |
| |
| |
| #define VGM_BIT_VALID 0 |
| #define VGM_BIT_INVALID 1 |
| |
| #define VGM_NIBBLE_VALID 0 |
| #define VGM_NIBBLE_INVALID 0xF |
| |
| #define VGM_BYTE_VALID 0 |
| #define VGM_BYTE_INVALID 0xFF |
| |
| #define VGM_WORD_VALID 0 |
| #define VGM_WORD_INVALID 0xFFFFFFFF |
| |
| #define VGM_EFLAGS_VALID 0xFFFFFFFE |
| #define VGM_EFLAGS_INVALID 0xFFFFFFFF |
| |
| |
| #define IS_ALIGNED4_ADDR(aaa_p) (0 == (((UInt)(aaa_p)) & 3)) |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Basic bitmap management, reading and writing. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Allocate and initialise a secondary map. */ |
| |
| static SecMap* alloc_secondary_map ( __attribute__ ((unused)) |
| Char* caller ) |
| { |
| SecMap* map; |
| UInt i; |
| PROF_EVENT(10); |
| |
| /* Mark all bytes as invalid access and invalid value. */ |
| |
| /* It just happens that a SecMap occupies exactly 18 pages -- |
| although this isn't important, so the following assert is |
| spurious. */ |
| vg_assert(0 == (sizeof(SecMap) % VKI_BYTES_PER_PAGE)); |
| map = VG_(get_memory_from_mmap)( sizeof(SecMap) ); |
| |
| for (i = 0; i < 8192; i++) |
| map->abits[i] = VGM_BYTE_INVALID; /* Invalid address */ |
| for (i = 0; i < 65536; i++) |
| map->vbyte[i] = VGM_BYTE_INVALID; /* Invalid Value */ |
| |
| /* VG_(printf)("ALLOC_2MAP(%s)\n", caller ); */ |
| return map; |
| } |
| |
| |
| /* Basic reading/writing of the bitmaps, for byte-sized accesses. */ |
| |
| static __inline__ UChar get_abit ( Addr a ) |
| { |
| SecMap* sm = VG_(primary_map)[a >> 16]; |
| UInt sm_off = a & 0xFFFF; |
| PROF_EVENT(20); |
| return BITARR_TEST(sm->abits, sm_off) |
| ? VGM_BIT_INVALID : VGM_BIT_VALID; |
| } |
| |
| static __inline__ UChar get_vbyte ( Addr a ) |
| { |
| SecMap* sm = VG_(primary_map)[a >> 16]; |
| UInt sm_off = a & 0xFFFF; |
| PROF_EVENT(21); |
| return sm->vbyte[sm_off]; |
| } |
| |
| static __inline__ void set_abit ( Addr a, UChar abit ) |
| { |
| SecMap* sm; |
| UInt sm_off; |
| PROF_EVENT(22); |
| ENSURE_MAPPABLE(a, "set_abit"); |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| if (abit) |
| BITARR_SET(sm->abits, sm_off); |
| else |
| BITARR_CLEAR(sm->abits, sm_off); |
| } |
| |
| static __inline__ void set_vbyte ( Addr a, UChar vbyte ) |
| { |
| SecMap* sm; |
| UInt sm_off; |
| PROF_EVENT(23); |
| ENSURE_MAPPABLE(a, "set_vbyte"); |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| sm->vbyte[sm_off] = vbyte; |
| } |
| |
| |
| /* Reading/writing of the bitmaps, for aligned word-sized accesses. */ |
| |
| static __inline__ UChar get_abits4_ALIGNED ( Addr a ) |
| { |
| SecMap* sm; |
| UInt sm_off; |
| UChar abits8; |
| PROF_EVENT(24); |
| # ifdef VG_DEBUG_MEMORY |
| vg_assert(IS_ALIGNED4_ADDR(a)); |
| # endif |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| abits8 = sm->abits[sm_off >> 3]; |
| abits8 >>= (a & 4 /* 100b */); /* a & 4 is either 0 or 4 */ |
| abits8 &= 0x0F; |
| return abits8; |
| } |
| |
| static UInt __inline__ get_vbytes4_ALIGNED ( Addr a ) |
| { |
| SecMap* sm = VG_(primary_map)[a >> 16]; |
| UInt sm_off = a & 0xFFFF; |
| PROF_EVENT(25); |
| # ifdef VG_DEBUG_MEMORY |
| vg_assert(IS_ALIGNED4_ADDR(a)); |
| # endif |
| return ((UInt*)(sm->vbyte))[sm_off >> 2]; |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Setting permissions over address ranges. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| static void set_address_range_perms ( Addr a, UInt len, |
| UInt example_a_bit, |
| UInt example_v_bit ) |
| { |
| UChar vbyte, abyte8; |
| UInt vword4, sm_off; |
| SecMap* sm; |
| |
| PROF_EVENT(30); |
| |
| if (len == 0) |
| return; |
| |
| if (len > 100 * 1000 * 1000) |
| VG_(message)(Vg_UserMsg, |
| "Warning: set address range perms: " |
| "large range %d, a %d, v %d", |
| len, example_a_bit, example_v_bit ); |
| |
| VGP_PUSHCC(VgpSARP); |
| |
| /* Requests to change permissions of huge address ranges may |
| indicate bugs in our machinery. 30,000,000 is arbitrary, but so |
| far all legitimate requests have fallen beneath that size. */ |
| /* 4 Mar 02: this is just stupid; get rid of it. */ |
| /* vg_assert(len < 30000000); */ |
| |
| /* Check the permissions make sense. */ |
| vg_assert(example_a_bit == VGM_BIT_VALID |
| || example_a_bit == VGM_BIT_INVALID); |
| vg_assert(example_v_bit == VGM_BIT_VALID |
| || example_v_bit == VGM_BIT_INVALID); |
| if (example_a_bit == VGM_BIT_INVALID) |
| vg_assert(example_v_bit == VGM_BIT_INVALID); |
| |
| /* The validity bits to write. */ |
| vbyte = example_v_bit==VGM_BIT_VALID |
| ? VGM_BYTE_VALID : VGM_BYTE_INVALID; |
| |
| /* In order that we can charge through the address space at 8 |
| bytes/main-loop iteration, make up some perms. */ |
| abyte8 = (example_a_bit << 7) |
| | (example_a_bit << 6) |
| | (example_a_bit << 5) |
| | (example_a_bit << 4) |
| | (example_a_bit << 3) |
| | (example_a_bit << 2) |
| | (example_a_bit << 1) |
| | (example_a_bit << 0); |
| vword4 = (vbyte << 24) | (vbyte << 16) | (vbyte << 8) | vbyte; |
| |
| # ifdef VG_DEBUG_MEMORY |
| /* Do it ... */ |
| while (True) { |
| PROF_EVENT(31); |
| if (len == 0) break; |
| set_abit ( a, example_a_bit ); |
| set_vbyte ( a, vbyte ); |
| a++; |
| len--; |
| } |
| |
| # else |
| /* Slowly do parts preceding 8-byte alignment. */ |
| while (True) { |
| PROF_EVENT(31); |
| if (len == 0) break; |
| if ((a % 8) == 0) break; |
| set_abit ( a, example_a_bit ); |
| set_vbyte ( a, vbyte ); |
| a++; |
| len--; |
| } |
| |
| if (len == 0) { |
| VGP_POPCC; |
| return; |
| } |
| vg_assert((a % 8) == 0 && len > 0); |
| |
| /* Once aligned, go fast. */ |
| while (True) { |
| PROF_EVENT(32); |
| if (len < 8) break; |
| ENSURE_MAPPABLE(a, "set_address_range_perms(fast)"); |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| sm->abits[sm_off >> 3] = abyte8; |
| ((UInt*)(sm->vbyte))[(sm_off >> 2) + 0] = vword4; |
| ((UInt*)(sm->vbyte))[(sm_off >> 2) + 1] = vword4; |
| a += 8; |
| len -= 8; |
| } |
| |
| if (len == 0) { |
| VGP_POPCC; |
| return; |
| } |
| vg_assert((a % 8) == 0 && len > 0 && len < 8); |
| |
| /* Finish the upper fragment. */ |
| while (True) { |
| PROF_EVENT(33); |
| if (len == 0) break; |
| set_abit ( a, example_a_bit ); |
| set_vbyte ( a, vbyte ); |
| a++; |
| len--; |
| } |
| # endif |
| |
| /* Check that zero page and highest page have not been written to |
| -- this could happen with buggy syscall wrappers. Today |
| (2001-04-26) had precisely such a problem with |
| __NR_setitimer. */ |
| vg_assert(VG_(first_and_last_secondaries_look_plausible)); |
| VGP_POPCC; |
| } |
| |
| |
| /* Set permissions for address ranges ... */ |
| |
| void VGM_(make_noaccess) ( Addr a, UInt len ) |
| { |
| PROF_EVENT(35); |
| set_address_range_perms ( a, len, VGM_BIT_INVALID, VGM_BIT_INVALID ); |
| } |
| |
| void VGM_(make_writable) ( Addr a, UInt len ) |
| { |
| PROF_EVENT(36); |
| set_address_range_perms ( a, len, VGM_BIT_VALID, VGM_BIT_INVALID ); |
| } |
| |
| void VGM_(make_readable) ( Addr a, UInt len ) |
| { |
| PROF_EVENT(37); |
| set_address_range_perms ( a, len, VGM_BIT_VALID, VGM_BIT_VALID ); |
| } |
| |
| void VGM_(make_readwritable) ( Addr a, UInt len ) |
| { |
| PROF_EVENT(38); |
| set_address_range_perms ( a, len, VGM_BIT_VALID, VGM_BIT_VALID ); |
| } |
| |
| /* Block-copy permissions (needed for implementing realloc()). */ |
| |
| void VGM_(copy_address_range_perms) ( Addr src, Addr dst, UInt len ) |
| { |
| UInt i; |
| PROF_EVENT(40); |
| for (i = 0; i < len; i++) { |
| UChar abit = get_abit ( src+i ); |
| UChar vbyte = get_vbyte ( src+i ); |
| PROF_EVENT(41); |
| set_abit ( dst+i, abit ); |
| set_vbyte ( dst+i, vbyte ); |
| } |
| } |
| |
| |
| /* Check permissions for address range. If inadequate permissions |
| exist, *bad_addr is set to the offending address, so the caller can |
| know what it is. */ |
| |
| Bool VGM_(check_writable) ( Addr a, UInt len, Addr* bad_addr ) |
| { |
| UInt i; |
| UChar abit; |
| PROF_EVENT(42); |
| for (i = 0; i < len; i++) { |
| PROF_EVENT(43); |
| abit = get_abit(a); |
| if (abit == VGM_BIT_INVALID) { |
| if (bad_addr != NULL) *bad_addr = a; |
| return False; |
| } |
| a++; |
| } |
| return True; |
| } |
| |
| Bool VGM_(check_readable) ( Addr a, UInt len, Addr* bad_addr ) |
| { |
| UInt i; |
| UChar abit; |
| UChar vbyte; |
| PROF_EVENT(44); |
| for (i = 0; i < len; i++) { |
| abit = get_abit(a); |
| vbyte = get_vbyte(a); |
| PROF_EVENT(45); |
| if (abit != VGM_BIT_VALID || vbyte != VGM_BYTE_VALID) { |
| if (bad_addr != NULL) *bad_addr = a; |
| return False; |
| } |
| a++; |
| } |
| return True; |
| } |
| |
| |
| /* Check a zero-terminated ascii string. Tricky -- don't want to |
| examine the actual bytes, to find the end, until we're sure it is |
| safe to do so. */ |
| |
| Bool VGM_(check_readable_asciiz) ( Addr a, Addr* bad_addr ) |
| { |
| UChar abit; |
| UChar vbyte; |
| PROF_EVENT(46); |
| while (True) { |
| PROF_EVENT(47); |
| abit = get_abit(a); |
| vbyte = get_vbyte(a); |
| if (abit != VGM_BIT_VALID || vbyte != VGM_BYTE_VALID) { |
| if (bad_addr != NULL) *bad_addr = a; |
| return False; |
| } |
| /* Ok, a is safe to read. */ |
| if (* ((UChar*)a) == 0) return True; |
| a++; |
| } |
| } |
| |
| |
| /* Setting permissions for aligned words. This supports fast stack |
| operations. */ |
| |
| static __inline__ void make_aligned_word_NOACCESS ( Addr a ) |
| { |
| SecMap* sm; |
| UInt sm_off; |
| UChar mask; |
| PROF_EVENT(50); |
| # ifdef VG_DEBUG_MEMORY |
| vg_assert(IS_ALIGNED4_ADDR(a)); |
| # endif |
| ENSURE_MAPPABLE(a, "make_aligned_word_NOACCESS"); |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| ((UInt*)(sm->vbyte))[sm_off >> 2] = VGM_WORD_INVALID; |
| mask = 0x0F; |
| mask <<= (a & 4 /* 100b */); /* a & 4 is either 0 or 4 */ |
| /* mask now contains 1s where we wish to make address bits |
| invalid (1s). */ |
| sm->abits[sm_off >> 3] |= mask; |
| } |
| |
| static __inline__ void make_aligned_word_WRITABLE ( Addr a ) |
| { |
| SecMap* sm; |
| UInt sm_off; |
| UChar mask; |
| PROF_EVENT(51); |
| # ifdef VG_DEBUG_MEMORY |
| vg_assert(IS_ALIGNED4_ADDR(a)); |
| # endif |
| ENSURE_MAPPABLE(a, "make_aligned_word_WRITABLE"); |
| sm = VG_(primary_map)[a >> 16]; |
| sm_off = a & 0xFFFF; |
| ((UInt*)(sm->vbyte))[sm_off >> 2] = VGM_WORD_INVALID; |
| mask = 0x0F; |
| mask <<= (a & 4 /* 100b */); /* a & 4 is either 0 or 4 */ |
| /* mask now contains 1s where we wish to make address bits |
| invalid (0s). */ |
| sm->abits[sm_off >> 3] &= ~mask; |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Functions called directly from generated code. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| static __inline__ UInt rotateRight16 ( UInt x ) |
| { |
| /* Amazingly, gcc turns this into a single rotate insn. */ |
| return (x >> 16) | (x << 16); |
| } |
| |
| |
| static __inline__ UInt shiftRight16 ( UInt x ) |
| { |
| return x >> 16; |
| } |
| |
| |
| /* Read/write 1/2/4 sized V bytes, and emit an address error if |
| needed. */ |
| |
| /* VG_(helperc_{LD,ST}V{1,2,4}) handle the common case fast. |
| Under all other circumstances, it defers to the relevant _SLOWLY |
| function, which can handle all situations. |
| */ |
| |
| UInt VG_(helperc_LOADV4) ( Addr a ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| return vgm_rd_V4_SLOWLY(a); |
| # else |
| UInt sec_no = rotateRight16(a) & 0x3FFFF; |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| UChar abits = sm->abits[a_off]; |
| abits >>= (a & 4); |
| abits &= 15; |
| PROF_EVENT(60); |
| if (abits == VGM_NIBBLE_VALID) { |
| /* Handle common case quickly: a is suitably aligned, is mapped, |
| and is addressible. */ |
| UInt v_off = a & 0xFFFF; |
| return ((UInt*)(sm->vbyte))[ v_off >> 2 ]; |
| } else { |
| /* Slow but general case. */ |
| return vgm_rd_V4_SLOWLY(a); |
| } |
| # endif |
| } |
| |
| void VG_(helperc_STOREV4) ( Addr a, UInt vbytes ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| vgm_wr_V4_SLOWLY(a, vbytes); |
| # else |
| UInt sec_no = rotateRight16(a) & 0x3FFFF; |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| UChar abits = sm->abits[a_off]; |
| abits >>= (a & 4); |
| abits &= 15; |
| PROF_EVENT(61); |
| if (abits == VGM_NIBBLE_VALID) { |
| /* Handle common case quickly: a is suitably aligned, is mapped, |
| and is addressible. */ |
| UInt v_off = a & 0xFFFF; |
| ((UInt*)(sm->vbyte))[ v_off >> 2 ] = vbytes; |
| } else { |
| /* Slow but general case. */ |
| vgm_wr_V4_SLOWLY(a, vbytes); |
| } |
| # endif |
| } |
| |
| UInt VG_(helperc_LOADV2) ( Addr a ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| return vgm_rd_V2_SLOWLY(a); |
| # else |
| UInt sec_no = rotateRight16(a) & 0x1FFFF; |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| PROF_EVENT(62); |
| if (sm->abits[a_off] == VGM_BYTE_VALID) { |
| /* Handle common case quickly. */ |
| UInt v_off = a & 0xFFFF; |
| return 0xFFFF0000 |
| | |
| (UInt)( ((UShort*)(sm->vbyte))[ v_off >> 1 ] ); |
| } else { |
| /* Slow but general case. */ |
| return vgm_rd_V2_SLOWLY(a); |
| } |
| # endif |
| } |
| |
| void VG_(helperc_STOREV2) ( Addr a, UInt vbytes ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| vgm_wr_V2_SLOWLY(a, vbytes); |
| # else |
| UInt sec_no = rotateRight16(a) & 0x1FFFF; |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| PROF_EVENT(63); |
| if (sm->abits[a_off] == VGM_BYTE_VALID) { |
| /* Handle common case quickly. */ |
| UInt v_off = a & 0xFFFF; |
| ((UShort*)(sm->vbyte))[ v_off >> 1 ] = vbytes & 0x0000FFFF; |
| } else { |
| /* Slow but general case. */ |
| vgm_wr_V2_SLOWLY(a, vbytes); |
| } |
| # endif |
| } |
| |
| UInt VG_(helperc_LOADV1) ( Addr a ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| return vgm_rd_V1_SLOWLY(a); |
| # else |
| UInt sec_no = shiftRight16(a); |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| PROF_EVENT(64); |
| if (sm->abits[a_off] == VGM_BYTE_VALID) { |
| /* Handle common case quickly. */ |
| UInt v_off = a & 0xFFFF; |
| return 0xFFFFFF00 |
| | |
| (UInt)( ((UChar*)(sm->vbyte))[ v_off ] ); |
| } else { |
| /* Slow but general case. */ |
| return vgm_rd_V1_SLOWLY(a); |
| } |
| # endif |
| } |
| |
| void VG_(helperc_STOREV1) ( Addr a, UInt vbytes ) |
| { |
| # ifdef VG_DEBUG_MEMORY |
| vgm_wr_V1_SLOWLY(a, vbytes); |
| # else |
| UInt sec_no = shiftRight16(a); |
| SecMap* sm = VG_(primary_map)[sec_no]; |
| UInt a_off = (a & 0xFFFF) >> 3; |
| PROF_EVENT(65); |
| if (sm->abits[a_off] == VGM_BYTE_VALID) { |
| /* Handle common case quickly. */ |
| UInt v_off = a & 0xFFFF; |
| ((UChar*)(sm->vbyte))[ v_off ] = vbytes & 0x000000FF; |
| } else { |
| /* Slow but general case. */ |
| vgm_wr_V1_SLOWLY(a, vbytes); |
| } |
| # endif |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Fallback functions to handle cases that the above ---*/ |
| /*--- VG_(helperc_{LD,ST}V{1,2,4}) can't manage. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| static UInt vgm_rd_V4_SLOWLY ( Addr a ) |
| { |
| Bool a0ok, a1ok, a2ok, a3ok; |
| UInt vb0, vb1, vb2, vb3; |
| |
| PROF_EVENT(70); |
| |
| /* First establish independently the addressibility of the 4 bytes |
| involved. */ |
| a0ok = get_abit(a+0) == VGM_BIT_VALID; |
| a1ok = get_abit(a+1) == VGM_BIT_VALID; |
| a2ok = get_abit(a+2) == VGM_BIT_VALID; |
| a3ok = get_abit(a+3) == VGM_BIT_VALID; |
| |
| /* Also get the validity bytes for the address. */ |
| vb0 = (UInt)get_vbyte(a+0); |
| vb1 = (UInt)get_vbyte(a+1); |
| vb2 = (UInt)get_vbyte(a+2); |
| vb3 = (UInt)get_vbyte(a+3); |
| |
| /* Now distinguish 3 cases */ |
| |
| /* Case 1: the address is completely valid, so: |
| - no addressing error |
| - return V bytes as read from memory |
| */ |
| if (a0ok && a1ok && a2ok && a3ok) { |
| UInt vw = VGM_WORD_INVALID; |
| vw <<= 8; vw |= vb3; |
| vw <<= 8; vw |= vb2; |
| vw <<= 8; vw |= vb1; |
| vw <<= 8; vw |= vb0; |
| return vw; |
| } |
| |
| /* Case 2: the address is completely invalid. |
| - emit addressing error |
| - return V word indicating validity. |
| This sounds strange, but if we make loads from invalid addresses |
| give invalid data, we also risk producing a number of confusing |
| undefined-value errors later, which confuses the fact that the |
| error arose in the first place from an invalid address. |
| */ |
| /* VG_(printf)("%p (%d %d %d %d)\n", a, a0ok, a1ok, a2ok, a3ok); */ |
| if (!VG_(clo_partial_loads_ok) |
| || ((a & 3) != 0) |
| || (!a0ok && !a1ok && !a2ok && !a3ok)) { |
| VG_(record_address_error)( a, 4, False ); |
| return (VGM_BYTE_VALID << 24) | (VGM_BYTE_VALID << 16) |
| | (VGM_BYTE_VALID << 8) | VGM_BYTE_VALID; |
| } |
| |
| /* Case 3: the address is partially valid. |
| - no addressing error |
| - returned V word is invalid where the address is invalid, |
| and contains V bytes from memory otherwise. |
| Case 3 is only allowed if VG_(clo_partial_loads_ok) is True |
| (which is the default), and the address is 4-aligned. |
| If not, Case 2 will have applied. |
| */ |
| vg_assert(VG_(clo_partial_loads_ok)); |
| { |
| UInt vw = VGM_WORD_INVALID; |
| vw <<= 8; vw |= (a3ok ? vb3 : VGM_BYTE_INVALID); |
| vw <<= 8; vw |= (a2ok ? vb2 : VGM_BYTE_INVALID); |
| vw <<= 8; vw |= (a1ok ? vb1 : VGM_BYTE_INVALID); |
| vw <<= 8; vw |= (a0ok ? vb0 : VGM_BYTE_INVALID); |
| return vw; |
| } |
| } |
| |
| static void vgm_wr_V4_SLOWLY ( Addr a, UInt vbytes ) |
| { |
| /* Check the address for validity. */ |
| Bool aerr = False; |
| PROF_EVENT(71); |
| |
| if (get_abit(a+0) != VGM_BIT_VALID) aerr = True; |
| if (get_abit(a+1) != VGM_BIT_VALID) aerr = True; |
| if (get_abit(a+2) != VGM_BIT_VALID) aerr = True; |
| if (get_abit(a+3) != VGM_BIT_VALID) aerr = True; |
| |
| /* Store the V bytes, remembering to do it little-endian-ly. */ |
| set_vbyte( a+0, vbytes & 0x000000FF ); vbytes >>= 8; |
| set_vbyte( a+1, vbytes & 0x000000FF ); vbytes >>= 8; |
| set_vbyte( a+2, vbytes & 0x000000FF ); vbytes >>= 8; |
| set_vbyte( a+3, vbytes & 0x000000FF ); |
| |
| /* If an address error has happened, report it. */ |
| if (aerr) |
| VG_(record_address_error)( a, 4, True ); |
| } |
| |
| static UInt vgm_rd_V2_SLOWLY ( Addr a ) |
| { |
| /* Check the address for validity. */ |
| UInt vw = VGM_WORD_INVALID; |
| Bool aerr = False; |
| PROF_EVENT(72); |
| |
| if (get_abit(a+0) != VGM_BIT_VALID) aerr = True; |
| if (get_abit(a+1) != VGM_BIT_VALID) aerr = True; |
| |
| /* Fetch the V bytes, remembering to do it little-endian-ly. */ |
| vw <<= 8; vw |= (UInt)get_vbyte(a+1); |
| vw <<= 8; vw |= (UInt)get_vbyte(a+0); |
| |
| /* If an address error has happened, report it. */ |
| if (aerr) { |
| VG_(record_address_error)( a, 2, False ); |
| vw = (VGM_BYTE_INVALID << 24) | (VGM_BYTE_INVALID << 16) |
| | (VGM_BYTE_VALID << 8) | (VGM_BYTE_VALID); |
| } |
| return vw; |
| } |
| |
| static void vgm_wr_V2_SLOWLY ( Addr a, UInt vbytes ) |
| { |
| /* Check the address for validity. */ |
| Bool aerr = False; |
| PROF_EVENT(73); |
| |
| if (get_abit(a+0) != VGM_BIT_VALID) aerr = True; |
| if (get_abit(a+1) != VGM_BIT_VALID) aerr = True; |
| |
| /* Store the V bytes, remembering to do it little-endian-ly. */ |
| set_vbyte( a+0, vbytes & 0x000000FF ); vbytes >>= 8; |
| set_vbyte( a+1, vbytes & 0x000000FF ); |
| |
| /* If an address error has happened, report it. */ |
| if (aerr) |
| VG_(record_address_error)( a, 2, True ); |
| } |
| |
| static UInt vgm_rd_V1_SLOWLY ( Addr a ) |
| { |
| /* Check the address for validity. */ |
| UInt vw = VGM_WORD_INVALID; |
| Bool aerr = False; |
| PROF_EVENT(74); |
| |
| if (get_abit(a+0) != VGM_BIT_VALID) aerr = True; |
| |
| /* Fetch the V byte. */ |
| vw <<= 8; vw |= (UInt)get_vbyte(a+0); |
| |
| /* If an address error has happened, report it. */ |
| if (aerr) { |
| VG_(record_address_error)( a, 1, False ); |
| vw = (VGM_BYTE_INVALID << 24) | (VGM_BYTE_INVALID << 16) |
| | (VGM_BYTE_INVALID << 8) | (VGM_BYTE_VALID); |
| } |
| return vw; |
| } |
| |
| static void vgm_wr_V1_SLOWLY ( Addr a, UInt vbytes ) |
| { |
| /* Check the address for validity. */ |
| Bool aerr = False; |
| PROF_EVENT(75); |
| if (get_abit(a+0) != VGM_BIT_VALID) aerr = True; |
| |
| /* Store the V bytes, remembering to do it little-endian-ly. */ |
| set_vbyte( a+0, vbytes & 0x000000FF ); |
| |
| /* If an address error has happened, report it. */ |
| if (aerr) |
| VG_(record_address_error)( a, 1, True ); |
| } |
| |
| |
| /* --------------------------------------------------------------------- |
| Called from generated code, or from the assembly helpers. |
| Handlers for value check failures. |
| ------------------------------------------------------------------ */ |
| |
| void VG_(helperc_value_check0_fail) ( void ) |
| { |
| VG_(record_value_error) ( 0 ); |
| } |
| |
| void VG_(helperc_value_check1_fail) ( void ) |
| { |
| VG_(record_value_error) ( 1 ); |
| } |
| |
| void VG_(helperc_value_check2_fail) ( void ) |
| { |
| VG_(record_value_error) ( 2 ); |
| } |
| |
| void VG_(helperc_value_check4_fail) ( void ) |
| { |
| VG_(record_value_error) ( 4 ); |
| } |
| |
| |
| /* --------------------------------------------------------------------- |
| FPU load and store checks, called from generated code. |
| ------------------------------------------------------------------ */ |
| |
| void VGM_(fpu_read_check) ( Addr addr, Int size ) |
| { |
| /* Ensure the read area is both addressible and valid (ie, |
| readable). If there's an address error, don't report a value |
| error too; but if there isn't an address error, check for a |
| value error. |
| |
| Try to be reasonably fast on the common case; wimp out and defer |
| to fpu_read_check_SLOWLY for everything else. */ |
| |
| SecMap* sm; |
| UInt sm_off, v_off, a_off; |
| Addr addr4; |
| |
| PROF_EVENT(80); |
| |
| # ifdef VG_DEBUG_MEMORY |
| fpu_read_check_SLOWLY ( addr, size ); |
| # else |
| |
| if (size == 4) { |
| if (!IS_ALIGNED4_ADDR(addr)) goto slow4; |
| PROF_EVENT(81); |
| /* Properly aligned. */ |
| sm = VG_(primary_map)[addr >> 16]; |
| sm_off = addr & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow4; |
| /* Properly aligned and addressible. */ |
| v_off = addr & 0xFFFF; |
| if (((UInt*)(sm->vbyte))[ v_off >> 2 ] != VGM_WORD_VALID) |
| goto slow4; |
| /* Properly aligned, addressible and with valid data. */ |
| return; |
| slow4: |
| fpu_read_check_SLOWLY ( addr, 4 ); |
| return; |
| } |
| |
| if (size == 8) { |
| if (!IS_ALIGNED4_ADDR(addr)) goto slow8; |
| PROF_EVENT(82); |
| /* Properly aligned. Do it in two halves. */ |
| addr4 = addr + 4; |
| /* First half. */ |
| sm = VG_(primary_map)[addr >> 16]; |
| sm_off = addr & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow8; |
| /* First half properly aligned and addressible. */ |
| v_off = addr & 0xFFFF; |
| if (((UInt*)(sm->vbyte))[ v_off >> 2 ] != VGM_WORD_VALID) |
| goto slow8; |
| /* Second half. */ |
| sm = VG_(primary_map)[addr4 >> 16]; |
| sm_off = addr4 & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow8; |
| /* Second half properly aligned and addressible. */ |
| v_off = addr4 & 0xFFFF; |
| if (((UInt*)(sm->vbyte))[ v_off >> 2 ] != VGM_WORD_VALID) |
| goto slow8; |
| /* Both halves properly aligned, addressible and with valid |
| data. */ |
| return; |
| slow8: |
| fpu_read_check_SLOWLY ( addr, 8 ); |
| return; |
| } |
| |
| /* Can't be bothered to huff'n'puff to make these (allegedly) rare |
| cases go quickly. */ |
| if (size == 2) { |
| PROF_EVENT(83); |
| fpu_read_check_SLOWLY ( addr, 2 ); |
| return; |
| } |
| |
| if (size == 10) { |
| PROF_EVENT(84); |
| fpu_read_check_SLOWLY ( addr, 10 ); |
| return; |
| } |
| |
| VG_(printf)("size is %d\n", size); |
| VG_(panic)("vgm_fpu_read_check: unhandled size"); |
| # endif |
| } |
| |
| |
| void VGM_(fpu_write_check) ( Addr addr, Int size ) |
| { |
| /* Ensure the written area is addressible, and moan if otherwise. |
| If it is addressible, make it valid, otherwise invalid. |
| */ |
| |
| SecMap* sm; |
| UInt sm_off, v_off, a_off; |
| Addr addr4; |
| |
| PROF_EVENT(85); |
| |
| # ifdef VG_DEBUG_MEMORY |
| fpu_write_check_SLOWLY ( addr, size ); |
| # else |
| |
| if (size == 4) { |
| if (!IS_ALIGNED4_ADDR(addr)) goto slow4; |
| PROF_EVENT(86); |
| /* Properly aligned. */ |
| sm = VG_(primary_map)[addr >> 16]; |
| sm_off = addr & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow4; |
| /* Properly aligned and addressible. Make valid. */ |
| v_off = addr & 0xFFFF; |
| ((UInt*)(sm->vbyte))[ v_off >> 2 ] = VGM_WORD_VALID; |
| return; |
| slow4: |
| fpu_write_check_SLOWLY ( addr, 4 ); |
| return; |
| } |
| |
| if (size == 8) { |
| if (!IS_ALIGNED4_ADDR(addr)) goto slow8; |
| PROF_EVENT(87); |
| /* Properly aligned. Do it in two halves. */ |
| addr4 = addr + 4; |
| /* First half. */ |
| sm = VG_(primary_map)[addr >> 16]; |
| sm_off = addr & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow8; |
| /* First half properly aligned and addressible. Make valid. */ |
| v_off = addr & 0xFFFF; |
| ((UInt*)(sm->vbyte))[ v_off >> 2 ] = VGM_WORD_VALID; |
| /* Second half. */ |
| sm = VG_(primary_map)[addr4 >> 16]; |
| sm_off = addr4 & 0xFFFF; |
| a_off = sm_off >> 3; |
| if (sm->abits[a_off] != VGM_BYTE_VALID) goto slow8; |
| /* Second half properly aligned and addressible. */ |
| v_off = addr4 & 0xFFFF; |
| ((UInt*)(sm->vbyte))[ v_off >> 2 ] = VGM_WORD_VALID; |
| /* Properly aligned, addressible and with valid data. */ |
| return; |
| slow8: |
| fpu_write_check_SLOWLY ( addr, 8 ); |
| return; |
| } |
| |
| /* Can't be bothered to huff'n'puff to make these (allegedly) rare |
| cases go quickly. */ |
| if (size == 2) { |
| PROF_EVENT(88); |
| fpu_write_check_SLOWLY ( addr, 2 ); |
| return; |
| } |
| |
| if (size == 10) { |
| PROF_EVENT(89); |
| fpu_write_check_SLOWLY ( addr, 10 ); |
| return; |
| } |
| |
| VG_(printf)("size is %d\n", size); |
| VG_(panic)("vgm_fpu_write_check: unhandled size"); |
| # endif |
| } |
| |
| |
| /* --------------------------------------------------------------------- |
| Slow, general cases for FPU load and store checks. |
| ------------------------------------------------------------------ */ |
| |
| /* Generic version. Test for both addr and value errors, but if |
| there's an addr error, don't report a value error even if it |
| exists. */ |
| |
| void fpu_read_check_SLOWLY ( Addr addr, Int size ) |
| { |
| Int i; |
| Bool aerr = False; |
| Bool verr = False; |
| PROF_EVENT(90); |
| for (i = 0; i < size; i++) { |
| PROF_EVENT(91); |
| if (get_abit(addr+i) != VGM_BIT_VALID) |
| aerr = True; |
| if (get_vbyte(addr+i) != VGM_BYTE_VALID) |
| verr = True; |
| } |
| |
| if (aerr) { |
| VG_(record_address_error)( addr, size, False ); |
| } else { |
| if (verr) |
| VG_(record_value_error)( size ); |
| } |
| } |
| |
| |
| /* Generic version. Test for addr errors. Valid addresses are |
| given valid values, and invalid addresses invalid values. */ |
| |
| void fpu_write_check_SLOWLY ( Addr addr, Int size ) |
| { |
| Int i; |
| Addr a_here; |
| Bool a_ok; |
| Bool aerr = False; |
| PROF_EVENT(92); |
| for (i = 0; i < size; i++) { |
| PROF_EVENT(93); |
| a_here = addr+i; |
| a_ok = get_abit(a_here) == VGM_BIT_VALID; |
| if (a_ok) { |
| set_vbyte(a_here, VGM_BYTE_VALID); |
| } else { |
| set_vbyte(a_here, VGM_BYTE_INVALID); |
| aerr = True; |
| } |
| } |
| if (aerr) { |
| VG_(record_address_error)( addr, size, True ); |
| } |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Tracking permissions around %esp changes. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* |
| The stack |
| ~~~~~~~~~ |
| The stack's segment seems to be dynamically extended downwards |
| by the kernel as the stack pointer moves down. Initially, a |
| 1-page (4k) stack is allocated. When %esp moves below that for |
| the first time, presumably a page fault occurs. The kernel |
| detects that the faulting address is in the range from %esp upwards |
| to the current valid stack. It then extends the stack segment |
| downwards for enough to cover the faulting address, and resumes |
| the process (invisibly). The process is unaware of any of this. |
| |
| That means that Valgrind can't spot when the stack segment is |
| being extended. Fortunately, we want to precisely and continuously |
| update stack permissions around %esp, so we need to spot all |
| writes to %esp anyway. |
| |
| The deal is: when %esp is assigned a lower value, the stack is |
| being extended. Create a secondary maps to fill in any holes |
| between the old stack ptr and this one, if necessary. Then |
| mark all bytes in the area just "uncovered" by this %esp change |
| as write-only. |
| |
| When %esp goes back up, mark the area receded over as unreadable |
| and unwritable. |
| |
| Just to record the %esp boundary conditions somewhere convenient: |
| %esp always points to the lowest live byte in the stack. All |
| addresses below %esp are not live; those at and above it are. |
| */ |
| |
| /* Does this address look like something in or vaguely near the |
| current thread's stack? */ |
| static |
| Bool is_plausible_stack_addr ( ThreadState* tst, Addr aa ) |
| { |
| UInt a = (UInt)aa; |
| PROF_EVENT(100); |
| if (a <= tst->stack_highest_word && |
| a > tst->stack_highest_word - VG_PLAUSIBLE_STACK_SIZE) |
| return True; |
| else |
| return False; |
| } |
| |
| |
| /* Is this address within some small distance below %ESP? Used only |
| for the --workaround-gcc296-bugs kludge. */ |
| Bool VG_(is_just_below_ESP)( Addr esp, Addr aa ) |
| { |
| if ((UInt)esp > (UInt)aa |
| && ((UInt)esp - (UInt)aa) <= VG_GCC296_BUG_STACK_SLOP) |
| return True; |
| else |
| return False; |
| } |
| |
| |
| /* Kludgey ... how much does %esp have to change before we reckon that |
| the application is switching stacks ? */ |
| #define VG_HUGE_DELTA (VG_PLAUSIBLE_STACK_SIZE / 4) |
| |
| static Addr get_page_base ( Addr a ) |
| { |
| return a & ~(VKI_BYTES_PER_PAGE-1); |
| } |
| |
| |
| static void vg_handle_esp_assignment_SLOWLY ( Addr ); |
| |
| void VGM_(handle_esp_assignment) ( Addr new_espA ) |
| { |
| UInt old_esp = VG_(baseBlock)[VGOFF_(m_esp)]; |
| UInt new_esp = (UInt)new_espA; |
| Int delta = ((Int)new_esp) - ((Int)old_esp); |
| |
| PROF_EVENT(101); |
| |
| # ifndef VG_DEBUG_MEMORY |
| |
| if (IS_ALIGNED4_ADDR(old_esp)) { |
| |
| /* Deal with the most common cases fast. These are ordered in |
| the sequence most common first. */ |
| |
| if (delta == -4) { |
| /* Moving down by 4 and properly aligned.. */ |
| PROF_EVENT(102); |
| make_aligned_word_WRITABLE(new_esp); |
| return; |
| } |
| |
| if (delta == 4) { |
| /* Moving up by 4 and properly aligned. */ |
| PROF_EVENT(103); |
| make_aligned_word_NOACCESS(old_esp); |
| return; |
| } |
| |
| if (delta == 16) { |
| /* Also surprisingly common. */ |
| PROF_EVENT(104); |
| make_aligned_word_NOACCESS(old_esp); |
| make_aligned_word_NOACCESS(old_esp+4); |
| make_aligned_word_NOACCESS(old_esp+8); |
| make_aligned_word_NOACCESS(old_esp+12); |
| return; |
| } |
| |
| if (delta == -12) { |
| PROF_EVENT(105); |
| make_aligned_word_WRITABLE(new_esp); |
| make_aligned_word_WRITABLE(new_esp+4); |
| make_aligned_word_WRITABLE(new_esp+8); |
| return; |
| } |
| |
| if (delta == 8) { |
| PROF_EVENT(106); |
| make_aligned_word_NOACCESS(old_esp); |
| make_aligned_word_NOACCESS(old_esp+4); |
| return; |
| } |
| |
| if (delta == -8) { |
| PROF_EVENT(107); |
| make_aligned_word_WRITABLE(new_esp); |
| make_aligned_word_WRITABLE(new_esp+4); |
| return; |
| } |
| } |
| |
| # endif |
| |
| /* The above special cases handle 90% to 95% of all the stack |
| adjustments. The rest we give to the slow-but-general |
| mechanism. */ |
| vg_handle_esp_assignment_SLOWLY ( new_espA ); |
| } |
| |
| |
| static void vg_handle_esp_assignment_SLOWLY ( Addr new_espA ) |
| { |
| UInt old_esp = VG_(baseBlock)[VGOFF_(m_esp)]; |
| UInt new_esp = (UInt)new_espA; |
| Int delta = ((Int)new_esp) - ((Int)old_esp); |
| |
| PROF_EVENT(110); |
| if (-(VG_HUGE_DELTA) < delta && delta < VG_HUGE_DELTA) { |
| /* "Ordinary" stack change. */ |
| if (new_esp < old_esp) { |
| /* Moving down; the stack is growing. */ |
| PROF_EVENT(111); |
| VGM_(make_writable) ( new_esp, old_esp - new_esp ); |
| return; |
| } |
| if (new_esp > old_esp) { |
| /* Moving up; the stack is shrinking. */ |
| PROF_EVENT(112); |
| VGM_(make_noaccess) ( old_esp, new_esp - old_esp ); |
| return; |
| } |
| PROF_EVENT(113); |
| return; /* when old_esp == new_esp */ |
| } |
| |
| /* %esp has changed by more than HUGE_DELTA. We take this to mean |
| that the application is switching to a new stack, for whatever |
| reason, and we attempt to initialise the permissions around the |
| new stack in some plausible way. All pretty kludgey; needed to |
| make netscape-4.07 run without generating thousands of error |
| contexts. |
| |
| If we appear to be switching back to the main stack, don't mess |
| with the permissions in the area at and above the stack ptr. |
| Otherwise, we're switching to an alternative stack; make the |
| area above %esp readable -- this doesn't seem right -- the right |
| thing to do would be to make it writable -- but is needed to |
| avoid huge numbers of errs in netscape. To be investigated. */ |
| |
| { Addr invalid_down_to = get_page_base(new_esp) |
| - 0 * VKI_BYTES_PER_PAGE; |
| Addr valid_up_to = get_page_base(new_esp) + VKI_BYTES_PER_PAGE |
| + 0 * VKI_BYTES_PER_PAGE; |
| ThreadState* tst = VG_(get_current_thread_state)(); |
| PROF_EVENT(114); |
| if (VG_(clo_verbosity) > 1) |
| VG_(message)(Vg_UserMsg, "Warning: client switching stacks? " |
| "%%esp: %p --> %p", |
| old_esp, new_esp); |
| /* VG_(printf)("na %p, %%esp %p, wr %p\n", |
| invalid_down_to, new_esp, valid_up_to ); */ |
| VGM_(make_noaccess) ( invalid_down_to, new_esp - invalid_down_to ); |
| if (!is_plausible_stack_addr(tst, new_esp)) { |
| VGM_(make_readable) ( new_esp, valid_up_to - new_esp ); |
| } |
| } |
| } |
| |
| |
| /*--------------------------------------------------------------*/ |
| /*--- Initialise the memory audit system on program startup. ---*/ |
| /*--------------------------------------------------------------*/ |
| |
| /* Handle one entry derived from /proc/self/maps. */ |
| |
| static |
| void init_memory_audit_callback ( |
| Addr start, UInt size, |
| Char rr, Char ww, Char xx, |
| UInt foffset, UChar* filename ) |
| { |
| UChar example_a_bit; |
| UChar example_v_bit; |
| UInt r_esp; |
| Bool is_stack_segment; |
| |
| /* Sanity check ... if this is the executable's text segment, |
| ensure it is loaded where we think it ought to be. Any file |
| name which doesn't contain ".so" is assumed to be the |
| executable. */ |
| if (filename != NULL |
| && xx == 'x' |
| && VG_(strstr(filename, ".so")) == NULL |
| ) { |
| /* We assume this is the executable. */ |
| if (start != VG_ASSUMED_EXE_BASE) { |
| VG_(message)(Vg_UserMsg, |
| "FATAL: executable base addr not as assumed."); |
| VG_(message)(Vg_UserMsg, "name %s, actual %p, assumed %p.", |
| filename, start, VG_ASSUMED_EXE_BASE); |
| VG_(message)(Vg_UserMsg, |
| "One reason this could happen is that you have a shared object"); |
| VG_(message)(Vg_UserMsg, |
| " whose name doesn't contain the characters \".so\", so Valgrind "); |
| VG_(message)(Vg_UserMsg, |
| "naively assumes it is the executable. "); |
| VG_(message)(Vg_UserMsg, |
| "In that case, rename it appropriately."); |
| VG_(panic)("VG_ASSUMED_EXE_BASE doesn't match reality"); |
| } |
| } |
| |
| if (0) |
| VG_(message)(Vg_DebugMsg, |
| "initial map %8x-%8x %c%c%c? %8x (%d) (%s)", |
| start,start+size,rr,ww,xx,foffset, |
| size, filename?filename:(UChar*)"NULL"); |
| |
| r_esp = VG_(baseBlock)[VGOFF_(m_esp)]; |
| is_stack_segment = start <= r_esp && r_esp < start+size; |
| |
| /* Figure out the segment's permissions. |
| |
| All segments are addressible -- since a process can read its |
| own text segment. |
| |
| A read-but-not-write segment presumably contains initialised |
| data, so is all valid. Read-write segments presumably contains |
| uninitialised data, so is all invalid. */ |
| |
| /* ToDo: make this less bogus. */ |
| if (rr != 'r' && xx != 'x' && ww != 'w') { |
| /* Very bogus; this path never gets taken. */ |
| /* A no, V no */ |
| example_a_bit = VGM_BIT_INVALID; |
| example_v_bit = VGM_BIT_INVALID; |
| } else { |
| /* A yes, V yes */ |
| example_a_bit = VGM_BIT_VALID; |
| example_v_bit = VGM_BIT_VALID; |
| /* Causes a lot of errs for unknown reasons. |
| if (filename is valgrind.so |
| [careful about end conditions on filename]) { |
| example_a_bit = VGM_BIT_INVALID; |
| example_v_bit = VGM_BIT_INVALID; |
| } |
| */ |
| } |
| |
| set_address_range_perms ( start, size, |
| example_a_bit, example_v_bit ); |
| |
| if (is_stack_segment) { |
| /* This is the stack segment. Mark all below %esp as |
| noaccess. */ |
| if (0) |
| VG_(message)(Vg_DebugMsg, |
| "invalidating stack area: %x .. %x", |
| start,r_esp); |
| VGM_(make_noaccess)( start, r_esp-start ); |
| } |
| } |
| |
| |
| |
| /* ONLY HERE for sbrk() */ |
| #include <unistd.h> |
| |
| /* Initialise the memory audit system. */ |
| void VGM_(init_memory_audit) ( void ) |
| { |
| Int i; |
| |
| init_prof_mem(); |
| |
| for (i = 0; i < 8192; i++) |
| vg_distinguished_secondary_map.abits[i] |
| = VGM_BYTE_INVALID; /* Invalid address */ |
| for (i = 0; i < 65536; i++) |
| vg_distinguished_secondary_map.vbyte[i] |
| = VGM_BYTE_INVALID; /* Invalid Value */ |
| |
| /* These entries gradually get overwritten as the used address |
| space expands. */ |
| for (i = 0; i < 65536; i++) |
| VG_(primary_map)[i] = &vg_distinguished_secondary_map; |
| /* These ones should never change; it's a bug in Valgrind if they |
| do. */ |
| for (i = 65536; i < 262144; i++) |
| VG_(primary_map)[i] = &vg_distinguished_secondary_map; |
| |
| /* Read the initial memory mapping from the /proc filesystem, and |
| set up our own maps accordingly. */ |
| VG_(read_procselfmaps) ( init_memory_audit_callback ); |
| |
| /* Last but not least, set up the shadow regs with reasonable (sic) |
| values. All regs are claimed to have valid values. |
| */ |
| VG_(baseBlock)[VGOFF_(sh_esp)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_ebp)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_eax)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_ecx)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_edx)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_ebx)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_esi)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_edi)] = VGM_WORD_VALID; |
| VG_(baseBlock)[VGOFF_(sh_eflags)] = VGM_EFLAGS_VALID; |
| |
| /* Record the end of the data segment, so that vg_syscall_mem.c |
| can make sense of calls to brk(). |
| */ |
| VGM_(curr_dataseg_end) = (Addr)sbrk(0); |
| if (VGM_(curr_dataseg_end) == (Addr)(-1)) |
| VG_(panic)("vgm_init_memory_audit: can't determine data-seg end"); |
| |
| if (0) |
| VG_(printf)("DS END is %p\n", (void*)VGM_(curr_dataseg_end)); |
| |
| /* Read the list of errors to suppress. This should be found in |
| the file specified by vg_clo_suppressions. */ |
| VG_(load_suppressions)(); |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Low-level address-space scanning, for the leak ---*/ |
| /*--- detector. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| static |
| jmp_buf memscan_jmpbuf; |
| |
| static |
| void vg_scan_all_valid_memory_sighandler ( Int sigNo ) |
| { |
| __builtin_longjmp(memscan_jmpbuf, 1); |
| } |
| |
| UInt VG_(scan_all_valid_memory) ( void (*notify_word)( Addr, UInt ) ) |
| { |
| /* All volatile, because some gccs seem paranoid about longjmp(). */ |
| volatile UInt res, numPages, page, vbytes, primaryMapNo, nWordsNotified; |
| volatile Addr pageBase, addr; |
| volatile SecMap* sm; |
| volatile UChar abits; |
| volatile UInt page_first_word; |
| |
| vki_ksigaction sigbus_saved; |
| vki_ksigaction sigbus_new; |
| vki_ksigaction sigsegv_saved; |
| vki_ksigaction sigsegv_new; |
| vki_ksigset_t blockmask_saved; |
| vki_ksigset_t unblockmask_new; |
| |
| /* Temporarily install a new sigsegv and sigbus handler, and make |
| sure SIGBUS, SIGSEGV and SIGTERM are unblocked. (Perhaps the |
| first two can never be blocked anyway?) */ |
| |
| sigbus_new.ksa_handler = vg_scan_all_valid_memory_sighandler; |
| sigbus_new.ksa_flags = VKI_SA_ONSTACK | VKI_SA_RESTART; |
| sigbus_new.ksa_restorer = NULL; |
| res = VG_(ksigemptyset)( &sigbus_new.ksa_mask ); |
| vg_assert(res == 0); |
| |
| sigsegv_new.ksa_handler = vg_scan_all_valid_memory_sighandler; |
| sigsegv_new.ksa_flags = VKI_SA_ONSTACK | VKI_SA_RESTART; |
| sigsegv_new.ksa_restorer = NULL; |
| res = VG_(ksigemptyset)( &sigsegv_new.ksa_mask ); |
| vg_assert(res == 0+0); |
| |
| res = VG_(ksigemptyset)( &unblockmask_new ); |
| res |= VG_(ksigaddset)( &unblockmask_new, VKI_SIGBUS ); |
| res |= VG_(ksigaddset)( &unblockmask_new, VKI_SIGSEGV ); |
| res |= VG_(ksigaddset)( &unblockmask_new, VKI_SIGTERM ); |
| vg_assert(res == 0+0+0); |
| |
| res = VG_(ksigaction)( VKI_SIGBUS, &sigbus_new, &sigbus_saved ); |
| vg_assert(res == 0+0+0+0); |
| |
| res = VG_(ksigaction)( VKI_SIGSEGV, &sigsegv_new, &sigsegv_saved ); |
| vg_assert(res == 0+0+0+0+0); |
| |
| res = VG_(ksigprocmask)( VKI_SIG_UNBLOCK, &unblockmask_new, &blockmask_saved ); |
| vg_assert(res == 0+0+0+0+0+0); |
| |
| /* The signal handlers are installed. Actually do the memory scan. */ |
| numPages = 1 << (32-VKI_BYTES_PER_PAGE_BITS); |
| vg_assert(numPages == 1048576); |
| vg_assert(4096 == (1 << VKI_BYTES_PER_PAGE_BITS)); |
| |
| nWordsNotified = 0; |
| |
| for (page = 0; page < numPages; page++) { |
| pageBase = page << VKI_BYTES_PER_PAGE_BITS; |
| primaryMapNo = pageBase >> 16; |
| sm = VG_(primary_map)[primaryMapNo]; |
| if (IS_DISTINGUISHED_SM(sm)) continue; |
| if (__builtin_setjmp(memscan_jmpbuf) == 0) { |
| /* try this ... */ |
| page_first_word = * (volatile UInt*)pageBase; |
| /* we get here if we didn't get a fault */ |
| /* Scan the page */ |
| for (addr = pageBase; addr < pageBase+VKI_BYTES_PER_PAGE; addr += 4) { |
| abits = get_abits4_ALIGNED(addr); |
| vbytes = get_vbytes4_ALIGNED(addr); |
| if (abits == VGM_NIBBLE_VALID |
| && vbytes == VGM_WORD_VALID) { |
| nWordsNotified++; |
| notify_word ( addr, *(UInt*)addr ); |
| } |
| } |
| } else { |
| /* We get here if reading the first word of the page caused a |
| fault, which in turn caused the signal handler to longjmp. |
| Ignore this page. */ |
| if (0) |
| VG_(printf)( |
| "vg_scan_all_valid_memory_sighandler: ignoring page at %p\n", |
| (void*)pageBase |
| ); |
| } |
| } |
| |
| /* Restore signal state to whatever it was before. */ |
| res = VG_(ksigaction)( VKI_SIGBUS, &sigbus_saved, NULL ); |
| vg_assert(res == 0 +0); |
| |
| res = VG_(ksigaction)( VKI_SIGSEGV, &sigsegv_saved, NULL ); |
| vg_assert(res == 0 +0 +0); |
| |
| res = VG_(ksigprocmask)( VKI_SIG_SETMASK, &blockmask_saved, NULL ); |
| vg_assert(res == 0 +0 +0 +0); |
| |
| return nWordsNotified; |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Detecting leaked (unreachable) malloc'd blocks. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* A block is either |
| -- Proper-ly reached; a pointer to its start has been found |
| -- Interior-ly reached; only an interior pointer to it has been found |
| -- Unreached; so far, no pointers to any part of it have been found. |
| */ |
| typedef |
| enum { Unreached, Interior, Proper } |
| Reachedness; |
| |
| /* A block record, used for generating err msgs. */ |
| typedef |
| struct _LossRecord { |
| struct _LossRecord* next; |
| /* Where these lost blocks were allocated. */ |
| ExeContext* allocated_at; |
| /* Their reachability. */ |
| Reachedness loss_mode; |
| /* Number of blocks and total # bytes involved. */ |
| UInt total_bytes; |
| UInt num_blocks; |
| } |
| LossRecord; |
| |
| |
| /* Find the i such that ptr points at or inside the block described by |
| shadows[i]. Return -1 if none found. This assumes that shadows[] |
| has been sorted on the ->data field. */ |
| |
| #ifdef VG_DEBUG_LEAKCHECK |
| /* Used to sanity-check the fast binary-search mechanism. */ |
| static Int find_shadow_for_OLD ( Addr ptr, |
| ShadowChunk** shadows, |
| Int n_shadows ) |
| |
| { |
| Int i; |
| Addr a_lo, a_hi; |
| PROF_EVENT(70); |
| for (i = 0; i < n_shadows; i++) { |
| PROF_EVENT(71); |
| a_lo = shadows[i]->data; |
| a_hi = ((Addr)shadows[i]->data) + shadows[i]->size - 1; |
| if (a_lo <= ptr && ptr <= a_hi) |
| return i; |
| } |
| return -1; |
| } |
| #endif |
| |
| |
| static Int find_shadow_for ( Addr ptr, |
| ShadowChunk** shadows, |
| Int n_shadows ) |
| { |
| Addr a_mid_lo, a_mid_hi; |
| Int lo, mid, hi, retVal; |
| PROF_EVENT(70); |
| /* VG_(printf)("find shadow for %p = ", ptr); */ |
| retVal = -1; |
| lo = 0; |
| hi = n_shadows-1; |
| while (True) { |
| PROF_EVENT(71); |
| |
| /* invariant: current unsearched space is from lo to hi, |
| inclusive. */ |
| if (lo > hi) break; /* not found */ |
| |
| mid = (lo + hi) / 2; |
| a_mid_lo = shadows[mid]->data; |
| a_mid_hi = ((Addr)shadows[mid]->data) + shadows[mid]->size - 1; |
| |
| if (ptr < a_mid_lo) { |
| hi = mid-1; |
| continue; |
| } |
| if (ptr > a_mid_hi) { |
| lo = mid+1; |
| continue; |
| } |
| vg_assert(ptr >= a_mid_lo && ptr <= a_mid_hi); |
| retVal = mid; |
| break; |
| } |
| |
| # ifdef VG_DEBUG_LEAKCHECK |
| vg_assert(retVal == find_shadow_for_OLD ( ptr, shadows, n_shadows )); |
| # endif |
| /* VG_(printf)("%d\n", retVal); */ |
| return retVal; |
| } |
| |
| |
| |
| static void sort_malloc_shadows ( ShadowChunk** shadows, UInt n_shadows ) |
| { |
| Int incs[14] = { 1, 4, 13, 40, 121, 364, 1093, 3280, |
| 9841, 29524, 88573, 265720, |
| 797161, 2391484 }; |
| Int lo = 0; |
| Int hi = n_shadows-1; |
| Int i, j, h, bigN, hp; |
| ShadowChunk* v; |
| |
| PROF_EVENT(72); |
| bigN = hi - lo + 1; if (bigN < 2) return; |
| hp = 0; while (incs[hp] < bigN) hp++; hp--; |
| |
| for (; hp >= 0; hp--) { |
| PROF_EVENT(73); |
| h = incs[hp]; |
| i = lo + h; |
| while (1) { |
| PROF_EVENT(74); |
| if (i > hi) break; |
| v = shadows[i]; |
| j = i; |
| while (shadows[j-h]->data > v->data) { |
| PROF_EVENT(75); |
| shadows[j] = shadows[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| shadows[j] = v; |
| i++; |
| } |
| } |
| } |
| |
| /* Globals, for the callback used by VG_(detect_memory_leaks). */ |
| |
| static ShadowChunk** vglc_shadows; |
| static Int vglc_n_shadows; |
| static Reachedness* vglc_reachedness; |
| static Addr vglc_min_mallocd_addr; |
| static Addr vglc_max_mallocd_addr; |
| |
| static |
| void vg_detect_memory_leaks_notify_addr ( Addr a, UInt word_at_a ) |
| { |
| Int sh_no; |
| Addr ptr = (Addr)word_at_a; |
| if (ptr >= vglc_min_mallocd_addr && ptr <= vglc_max_mallocd_addr) { |
| /* Might be legitimate; we'll have to investigate further. */ |
| sh_no = find_shadow_for ( ptr, vglc_shadows, vglc_n_shadows ); |
| if (sh_no != -1) { |
| /* Found a block at/into which ptr points. */ |
| vg_assert(sh_no >= 0 && sh_no < vglc_n_shadows); |
| vg_assert(ptr < vglc_shadows[sh_no]->data |
| + vglc_shadows[sh_no]->size); |
| /* Decide whether Proper-ly or Interior-ly reached. */ |
| if (ptr == vglc_shadows[sh_no]->data) { |
| vglc_reachedness[sh_no] = Proper; |
| } else { |
| if (vglc_reachedness[sh_no] == Unreached) |
| vglc_reachedness[sh_no] = Interior; |
| } |
| } |
| } |
| } |
| |
| |
| void VG_(detect_memory_leaks) ( void ) |
| { |
| Int i; |
| Int blocks_leaked, bytes_leaked; |
| Int blocks_dubious, bytes_dubious; |
| Int blocks_reachable, bytes_reachable; |
| Int n_lossrecords; |
| UInt bytes_notified; |
| |
| LossRecord* errlist; |
| LossRecord* p; |
| |
| Bool (*ec_comparer_fn) ( ExeContext*, ExeContext* ); |
| PROF_EVENT(76); |
| vg_assert(VG_(clo_instrument)); |
| |
| /* Decide how closely we want to match ExeContexts in leak |
| records. */ |
| switch (VG_(clo_leak_resolution)) { |
| case 2: |
| ec_comparer_fn = VG_(eq_ExeContext_top2); |
| break; |
| case 4: |
| ec_comparer_fn = VG_(eq_ExeContext_top4); |
| break; |
| case VG_DEEPEST_BACKTRACE: |
| ec_comparer_fn = VG_(eq_ExeContext_all); |
| break; |
| default: |
| VG_(panic)("VG_(detect_memory_leaks): " |
| "bad VG_(clo_leak_resolution)"); |
| break; |
| } |
| |
| /* vg_get_malloc_shadows allocates storage for shadows */ |
| vglc_shadows = VG_(get_malloc_shadows)( &vglc_n_shadows ); |
| if (vglc_n_shadows == 0) { |
| vg_assert(vglc_shadows == NULL); |
| VG_(message)(Vg_UserMsg, |
| "No malloc'd blocks -- no leaks are possible.\n"); |
| return; |
| } |
| |
| VG_(message)(Vg_UserMsg, |
| "searching for pointers to %d not-freed blocks.", |
| vglc_n_shadows ); |
| sort_malloc_shadows ( vglc_shadows, vglc_n_shadows ); |
| |
| /* Sanity check; assert that the blocks are now in order and that |
| they don't overlap. */ |
| for (i = 0; i < vglc_n_shadows-1; i++) { |
| vg_assert( ((Addr)vglc_shadows[i]->data) |
| < ((Addr)vglc_shadows[i+1]->data) ); |
| vg_assert( ((Addr)vglc_shadows[i]->data) + vglc_shadows[i]->size |
| < ((Addr)vglc_shadows[i+1]->data) ); |
| } |
| |
| vglc_min_mallocd_addr = ((Addr)vglc_shadows[0]->data); |
| vglc_max_mallocd_addr = ((Addr)vglc_shadows[vglc_n_shadows-1]->data) |
| + vglc_shadows[vglc_n_shadows-1]->size - 1; |
| |
| vglc_reachedness |
| = VG_(malloc)( VG_AR_PRIVATE, vglc_n_shadows * sizeof(Reachedness) ); |
| for (i = 0; i < vglc_n_shadows; i++) |
| vglc_reachedness[i] = Unreached; |
| |
| /* Do the scan of memory. */ |
| bytes_notified |
| = VG_(scan_all_valid_memory)( &vg_detect_memory_leaks_notify_addr ) |
| * VKI_BYTES_PER_WORD; |
| |
| VG_(message)(Vg_UserMsg, "checked %d bytes.", bytes_notified); |
| |
| blocks_leaked = bytes_leaked = 0; |
| blocks_dubious = bytes_dubious = 0; |
| blocks_reachable = bytes_reachable = 0; |
| |
| for (i = 0; i < vglc_n_shadows; i++) { |
| if (vglc_reachedness[i] == Unreached) { |
| blocks_leaked++; |
| bytes_leaked += vglc_shadows[i]->size; |
| } |
| else if (vglc_reachedness[i] == Interior) { |
| blocks_dubious++; |
| bytes_dubious += vglc_shadows[i]->size; |
| } |
| else if (vglc_reachedness[i] == Proper) { |
| blocks_reachable++; |
| bytes_reachable += vglc_shadows[i]->size; |
| } |
| } |
| |
| VG_(message)(Vg_UserMsg, ""); |
| VG_(message)(Vg_UserMsg, "definitely lost: %d bytes in %d blocks.", |
| bytes_leaked, blocks_leaked ); |
| VG_(message)(Vg_UserMsg, "possibly lost: %d bytes in %d blocks.", |
| bytes_dubious, blocks_dubious ); |
| VG_(message)(Vg_UserMsg, "still reachable: %d bytes in %d blocks.", |
| bytes_reachable, blocks_reachable ); |
| |
| |
| /* Common up the lost blocks so we can print sensible error |
| messages. */ |
| |
| n_lossrecords = 0; |
| errlist = NULL; |
| for (i = 0; i < vglc_n_shadows; i++) { |
| for (p = errlist; p != NULL; p = p->next) { |
| if (p->loss_mode == vglc_reachedness[i] |
| && ec_comparer_fn ( |
| p->allocated_at, |
| vglc_shadows[i]->where) ) { |
| break; |
| } |
| } |
| if (p != NULL) { |
| p->num_blocks ++; |
| p->total_bytes += vglc_shadows[i]->size; |
| } else { |
| n_lossrecords ++; |
| p = VG_(malloc)(VG_AR_PRIVATE, sizeof(LossRecord)); |
| p->loss_mode = vglc_reachedness[i]; |
| p->allocated_at = vglc_shadows[i]->where; |
| p->total_bytes = vglc_shadows[i]->size; |
| p->num_blocks = 1; |
| p->next = errlist; |
| errlist = p; |
| } |
| } |
| |
| for (i = 0; i < n_lossrecords; i++) { |
| LossRecord* p_min = NULL; |
| UInt n_min = 0xFFFFFFFF; |
| for (p = errlist; p != NULL; p = p->next) { |
| if (p->num_blocks > 0 && p->total_bytes < n_min) { |
| n_min = p->total_bytes; |
| p_min = p; |
| } |
| } |
| vg_assert(p_min != NULL); |
| |
| if ( (!VG_(clo_show_reachable)) && p_min->loss_mode == Proper) { |
| p_min->num_blocks = 0; |
| continue; |
| } |
| |
| VG_(message)(Vg_UserMsg, ""); |
| VG_(message)( |
| Vg_UserMsg, |
| "%d bytes in %d blocks are %s in loss record %d of %d", |
| p_min->total_bytes, p_min->num_blocks, |
| p_min->loss_mode==Unreached ? "definitely lost" : |
| (p_min->loss_mode==Interior ? "possibly lost" |
| : "still reachable"), |
| i+1, n_lossrecords |
| ); |
| VG_(pp_ExeContext)(p_min->allocated_at); |
| p_min->num_blocks = 0; |
| } |
| |
| VG_(message)(Vg_UserMsg, ""); |
| VG_(message)(Vg_UserMsg, "LEAK SUMMARY:"); |
| VG_(message)(Vg_UserMsg, " possibly lost: %d bytes in %d blocks.", |
| bytes_dubious, blocks_dubious ); |
| VG_(message)(Vg_UserMsg, " definitely lost: %d bytes in %d blocks.", |
| bytes_leaked, blocks_leaked ); |
| VG_(message)(Vg_UserMsg, " still reachable: %d bytes in %d blocks.", |
| bytes_reachable, blocks_reachable ); |
| if (!VG_(clo_show_reachable)) { |
| VG_(message)(Vg_UserMsg, |
| "Reachable blocks (those to which a pointer was found) are not shown."); |
| VG_(message)(Vg_UserMsg, |
| "To see them, rerun with: --show-reachable=yes"); |
| } |
| VG_(message)(Vg_UserMsg, ""); |
| |
| VG_(free) ( VG_AR_PRIVATE, vglc_shadows ); |
| VG_(free) ( VG_AR_PRIVATE, vglc_reachedness ); |
| } |
| |
| |
| /* --------------------------------------------------------------------- |
| Sanity check machinery (permanently engaged). |
| ------------------------------------------------------------------ */ |
| |
| /* Check that nobody has spuriously claimed that the first or last 16 |
| pages (64 KB) of address space have become accessible. Failure of |
| the following do not per se indicate an internal consistency |
| problem, but they are so likely to that we really want to know |
| about it if so. */ |
| |
| Bool VG_(first_and_last_secondaries_look_plausible) ( void ) |
| { |
| if (IS_DISTINGUISHED_SM(VG_(primary_map)[0]) |
| && IS_DISTINGUISHED_SM(VG_(primary_map)[65535])) { |
| return True; |
| } else { |
| return False; |
| } |
| } |
| |
| |
| /* A fast sanity check -- suitable for calling circa once per |
| millisecond. */ |
| |
| void VG_(do_sanity_checks) ( ThreadId tid, Bool force_expensive ) |
| { |
| Int i; |
| Bool do_expensive_checks; |
| ThreadState* tst; |
| |
| if (VG_(sanity_level) < 1) return; |
| |
| /* --- First do all the tests that we can do quickly. ---*/ |
| |
| VG_(sanity_fast_count)++; |
| |
| tst = VG_(get_thread_state)(tid); |
| vg_assert(tst != NULL && tst->status != VgTs_Empty); |
| |
| /* Check that we haven't overrun our private stack. */ |
| for (i = 0; i < 10; i++) { |
| vg_assert(VG_(stack)[i] |
| == ((UInt)(&VG_(stack)[i]) ^ 0xA4B3C2D1)); |
| vg_assert(VG_(stack)[10000-1-i] |
| == ((UInt)(&VG_(stack)[10000-i-1]) ^ 0xABCD4321)); |
| } |
| |
| /* Check stuff pertaining to the memory check system. */ |
| |
| if (VG_(clo_instrument)) { |
| |
| /* Check that the eflags tag is as expected. */ |
| UInt vv = tst->sh_eflags; |
| vg_assert(vv == VGM_EFLAGS_VALID || VGM_EFLAGS_INVALID); |
| |
| /* Check that nobody has spuriously claimed that the first or |
| last 16 pages of memory have become accessible [...] */ |
| vg_assert(VG_(first_and_last_secondaries_look_plausible)); |
| } |
| |
| /* --- Now some more expensive checks. ---*/ |
| |
| /* Once every 25 times, check some more expensive stuff. */ |
| |
| do_expensive_checks = False; |
| if (force_expensive) |
| do_expensive_checks = True; |
| if (VG_(sanity_level) > 1) |
| do_expensive_checks = True; |
| if (VG_(sanity_level) == 1 |
| && (VG_(sanity_fast_count) % 25) == 0) |
| do_expensive_checks = True; |
| |
| if (do_expensive_checks) { |
| VG_(sanity_slow_count)++; |
| |
| # if 0 |
| { void zzzmemscan(void); zzzmemscan(); } |
| # endif |
| |
| if ((VG_(sanity_fast_count) % 250) == 0) |
| VG_(sanity_check_tc_tt)(); |
| |
| if (VG_(clo_instrument)) { |
| /* Make sure nobody changed the distinguished secondary. */ |
| for (i = 0; i < 8192; i++) |
| vg_assert(vg_distinguished_secondary_map.abits[i] |
| == VGM_BYTE_INVALID); |
| for (i = 0; i < 65536; i++) |
| vg_assert(vg_distinguished_secondary_map.vbyte[i] |
| == VGM_BYTE_INVALID); |
| |
| /* Make sure that the upper 3/4 of the primary map hasn't |
| been messed with. */ |
| for (i = 65536; i < 262144; i++) |
| vg_assert(VG_(primary_map)[i] |
| == & vg_distinguished_secondary_map); |
| } |
| /* |
| if ((VG_(sanity_fast_count) % 500) == 0) VG_(mallocSanityCheckAll)(); |
| */ |
| } |
| |
| if (VG_(sanity_level) > 1) { |
| /* Check sanity of the low-level memory manager. Note that bugs |
| in the client's code can cause this to fail, so we don't do |
| this check unless specially asked for. And because it's |
| potentially very expensive. */ |
| VG_(mallocSanityCheckAll)(); |
| } |
| } |
| |
| |
| /* --------------------------------------------------------------------- |
| Debugging machinery (turn on to debug). Something of a mess. |
| ------------------------------------------------------------------ */ |
| |
| /* Print the value tags on the 8 integer registers & flag reg. */ |
| |
| static void uint_to_bits ( UInt x, Char* str ) |
| { |
| Int i; |
| Int w = 0; |
| /* str must point to a space of at least 36 bytes. */ |
| for (i = 31; i >= 0; i--) { |
| str[w++] = (x & ( ((UInt)1) << i)) ? '1' : '0'; |
| if (i == 24 || i == 16 || i == 8) |
| str[w++] = ' '; |
| } |
| str[w++] = 0; |
| vg_assert(w == 36); |
| } |
| |
| /* Caution! Not vthread-safe; looks in VG_(baseBlock), not the thread |
| state table. */ |
| |
| void VG_(show_reg_tags) ( void ) |
| { |
| Char buf1[36]; |
| Char buf2[36]; |
| UInt z_eax, z_ebx, z_ecx, z_edx, |
| z_esi, z_edi, z_ebp, z_esp, z_eflags; |
| |
| z_eax = VG_(baseBlock)[VGOFF_(sh_eax)]; |
| z_ebx = VG_(baseBlock)[VGOFF_(sh_ebx)]; |
| z_ecx = VG_(baseBlock)[VGOFF_(sh_ecx)]; |
| z_edx = VG_(baseBlock)[VGOFF_(sh_edx)]; |
| z_esi = VG_(baseBlock)[VGOFF_(sh_esi)]; |
| z_edi = VG_(baseBlock)[VGOFF_(sh_edi)]; |
| z_ebp = VG_(baseBlock)[VGOFF_(sh_ebp)]; |
| z_esp = VG_(baseBlock)[VGOFF_(sh_esp)]; |
| z_eflags = VG_(baseBlock)[VGOFF_(sh_eflags)]; |
| |
| uint_to_bits(z_eflags, buf1); |
| VG_(message)(Vg_DebugMsg, "efl %\n", buf1); |
| |
| uint_to_bits(z_eax, buf1); |
| uint_to_bits(z_ebx, buf2); |
| VG_(message)(Vg_DebugMsg, "eax %s ebx %s\n", buf1, buf2); |
| |
| uint_to_bits(z_ecx, buf1); |
| uint_to_bits(z_edx, buf2); |
| VG_(message)(Vg_DebugMsg, "ecx %s edx %s\n", buf1, buf2); |
| |
| uint_to_bits(z_esi, buf1); |
| uint_to_bits(z_edi, buf2); |
| VG_(message)(Vg_DebugMsg, "esi %s edi %s\n", buf1, buf2); |
| |
| uint_to_bits(z_ebp, buf1); |
| uint_to_bits(z_esp, buf2); |
| VG_(message)(Vg_DebugMsg, "ebp %s esp %s\n", buf1, buf2); |
| } |
| |
| |
| #if 0 |
| /* For debugging only. Scan the address space and touch all allegedly |
| addressible words. Useful for establishing where Valgrind's idea of |
| addressibility has diverged from what the kernel believes. */ |
| |
| static |
| void zzzmemscan_notify_word ( Addr a, UInt w ) |
| { |
| } |
| |
| void zzzmemscan ( void ) |
| { |
| Int n_notifies |
| = VG_(scan_all_valid_memory)( zzzmemscan_notify_word ); |
| VG_(printf)("zzzmemscan: n_bytes = %d\n", 4 * n_notifies ); |
| } |
| #endif |
| |
| |
| |
| |
| #if 0 |
| static Int zzz = 0; |
| |
| void show_bb ( Addr eip_next ) |
| { |
| VG_(printf)("[%4d] ", zzz); |
| VG_(show_reg_tags)( &VG_(m_shadow ); |
| VG_(translate) ( eip_next, NULL, NULL, NULL ); |
| } |
| #endif /* 0 */ |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end vg_memory.c ---*/ |
| /*--------------------------------------------------------------------*/ |