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authorAlexandre Oliva <aoliva@redhat.com>2015-03-17 01:14:11 -0300
committerAlexandre Oliva <aoliva@redhat.com>2015-03-17 00:31:49 -0300
commitf8aeae347377f3dfa8cbadde057adf1827fb1d44 (patch)
treecee16d94d0f5b7061455667057da4f141f98b9ae /nptl_db
parentb97eb2bdb1ed72982a7821c3078be591051cef59 (diff)
downloadglibc-f8aeae347377f3dfa8cbadde057adf1827fb1d44.tar.gz
Fix DTV race, assert, DTV_SURPLUS Static TLS limit, and nptl_db garbage
for ChangeLog [BZ #17090] [BZ #17620] [BZ #17621] [BZ #17628] * NEWS: Update. * elf/dl-tls.c (_dl_update_slotinfo): Clean up outdated DTV entries with Static TLS too. Skip entries past the end of the allocated DTV, from Alan Modra. (tls_get_addr_tail): Update to glibc_likely/unlikely. Move Static TLS DTV entry set up from... (_dl_allocate_tls_init): ... here (fix modid assertion), ... * elf/dl-reloc.c (_dl_nothread_init_static_tls): ... here... * nptl/allocatestack.c (init_one_static_tls): ... and here... * elf/dlopen.c (dl_open_worker): Drop l_tls_modid upper bound for Static TLS. * elf/tlsdeschtab.h (map_generation): Return size_t. Check that the slot we find is associated with the given map before using its generation count. * nptl_db/db_info.c: Include ldsodefs.h. (rtld_global, dtv_slotinfo_list, dtv_slotinfo): New typedefs. * nptl_db/structs.def (DB_RTLD_VARIABLE): New macro. (DB_MAIN_VARIABLE, DB_RTLD_GLOBAL_FIELD): Likewise. (link_map::l_tls_offset): New struct field. (dtv_t::counter): Likewise. (rtld_global): New struct. (_rtld_global): New rtld variable. (dl_tls_dtv_slotinfo_list): New rtld global field. (dtv_slotinfo_list): New struct. (dtv_slotinfo): Likewise. * nptl_db/td_symbol_list.c: Drop gnu/lib-names.h include. (td_lookup): Rename to... (td_mod_lookup): ... this. Use new mod parameter instead of LIBPTHREAD_SO. * nptl_db/td_thr_tlsbase.c: Include link.h. (dtv_slotinfo_list, dtv_slotinfo): New functions. (td_thr_tlsbase): Check DTV generation. Compute Static TLS addresses even if the DTV is out of date or missing them. * nptl_db/fetch-value.c (_td_locate_field): Do not refuse to index zero-length arrays. * nptl_db/thread_dbP.h: Include gnu/lib-names.h. (td_lookup): Make it a macro implemented in terms of... (td_mod_lookup): ... this declaration. * nptl_db/db-symbols.awk (DB_RTLD_VARIABLE): Override. (DB_MAIN_VARIABLE): Likewise.
Diffstat (limited to 'nptl_db')
-rw-r--r--nptl_db/db-symbols.awk2
-rw-r--r--nptl_db/db_info.c4
-rw-r--r--nptl_db/fetch-value.c3
-rw-r--r--nptl_db/structs.def39
-rw-r--r--nptl_db/td_symbol_list.c7
-rw-r--r--nptl_db/td_thr_tlsbase.c172
-rw-r--r--nptl_db/thread_dbP.h11
7 files changed, 226 insertions, 12 deletions
diff --git a/nptl_db/db-symbols.awk b/nptl_db/db-symbols.awk
index f9a91b93bf..eb089e188a 100644
--- a/nptl_db/db-symbols.awk
+++ b/nptl_db/db-symbols.awk
@@ -2,6 +2,8 @@
# we've just built. It checks for all the symbols used in td_symbol_list.
BEGIN {
+%define DB_RTLD_VARIABLE(name) /* Nothing. */
+%define DB_MAIN_VARIABLE(name) /* Nothing. */
%define DB_LOOKUP_NAME(idx, name) required[STRINGIFY (name)] = 1;
%define DB_LOOKUP_NAME_TH_UNIQUE(idx, name) th_unique[STRINGIFY (name)] = 1;
%include "db-symbols.h"
diff --git a/nptl_db/db_info.c b/nptl_db/db_info.c
index d4a5438fba..b88b4c0718 100644
--- a/nptl_db/db_info.c
+++ b/nptl_db/db_info.c
@@ -21,6 +21,7 @@
#include <stdint.h>
#include "thread_dbP.h"
#include <tls.h>
+#include <ldsodefs.h>
typedef struct pthread pthread;
typedef struct pthread_key_struct pthread_key_struct;
@@ -37,6 +38,9 @@ typedef struct
} dtv;
typedef struct link_map link_map;
+typedef struct rtld_global rtld_global;
+typedef struct dtv_slotinfo_list dtv_slotinfo_list;
+typedef struct dtv_slotinfo dtv_slotinfo;
/* Actually static in nptl/init.c, but we only need it for typeof. */
extern bool __nptl_initial_report_events;
diff --git a/nptl_db/fetch-value.c b/nptl_db/fetch-value.c
index afc26fc1ef..8a5a30cb1f 100644
--- a/nptl_db/fetch-value.c
+++ b/nptl_db/fetch-value.c
@@ -69,7 +69,8 @@ _td_locate_field (td_thragent_t *ta,
}
}
- if (idx != 0 && idx - (psaddr_t) 0 > DB_DESC_NELEM (desc))
+ if (idx != 0 && DB_DESC_NELEM (desc) != 0
+ && idx - (psaddr_t) 0 > DB_DESC_NELEM (desc))
/* This is an internal indicator to callers with nonzero IDX
that the IDX value is too big. */
return TD_NOAPLIC;
diff --git a/nptl_db/structs.def b/nptl_db/structs.def
index 42e8b4df06..0d49a0ae5e 100644
--- a/nptl_db/structs.def
+++ b/nptl_db/structs.def
@@ -22,6 +22,28 @@
# define STRUCTS_DEF_DEFAULTS 1
#endif
+#ifndef DB_RTLD_VARIABLE
+# define DB_RTLD_VARIABLE(name) DB_VARIABLE (name)
+#endif
+
+#ifndef DB_MAIN_VARIABLE
+# define DB_MAIN_VARIABLE(name) DB_VARIABLE (name)
+#endif
+
+#ifndef DB_RTLD_GLOBAL_FIELD
+# if !IS_IN (libpthread)
+# define DB_RTLD_GLOBAL_FIELD(field) \
+ DB_STRUCT_FIELD (rtld_global, _##field) \
+ DB_MAIN_VARIABLE (_##field)
+# elif defined SHARED
+# define DB_RTLD_GLOBAL_FIELD(field) \
+ DB_STRUCT_FIELD (rtld_global, _##field)
+# else
+# define DB_RTLD_GLOBAL_FIELD(field) \
+ DB_MAIN_VARIABLE (_##field)
+# endif
+#endif /* DB_RTLD_GLOBAL_FIELD */
+
DB_STRUCT (pthread)
DB_STRUCT_FIELD (pthread, list)
DB_STRUCT_FIELD (pthread, report_events)
@@ -70,14 +92,31 @@ DB_STRUCT (pthread_key_data_level2)
DB_STRUCT_ARRAY_FIELD (pthread_key_data_level2, data)
DB_STRUCT_FIELD (link_map, l_tls_modid)
+DB_STRUCT_FIELD (link_map, l_tls_offset)
DB_STRUCT_ARRAY_FIELD (dtv, dtv)
#define pointer_val pointer.val /* Field of anonymous struct in dtv_t. */
DB_STRUCT_FIELD (dtv_t, pointer_val)
+DB_STRUCT_FIELD (dtv_t, counter)
#if !IS_IN (libpthread) || TLS_TCB_AT_TP
DB_STRUCT_FIELD (pthread, dtvp)
#endif
+#if !(IS_IN (libpthread) && !defined SHARED)
+DB_STRUCT (rtld_global)
+DB_RTLD_VARIABLE (_rtld_global)
+#endif
+DB_RTLD_GLOBAL_FIELD (dl_tls_dtv_slotinfo_list)
+
+DB_STRUCT (dtv_slotinfo_list)
+DB_STRUCT_FIELD (dtv_slotinfo_list, len)
+DB_STRUCT_FIELD (dtv_slotinfo_list, next)
+DB_STRUCT_ARRAY_FIELD (dtv_slotinfo_list, slotinfo)
+
+DB_STRUCT (dtv_slotinfo)
+DB_STRUCT_FIELD (dtv_slotinfo, gen)
+DB_STRUCT_FIELD (dtv_slotinfo, map)
+
#ifdef STRUCTS_DEF_DEFAULTS
# undef DB_STRUCT_ARRAY_FIELD
# undef DB_ARRAY_VARIABLE
diff --git a/nptl_db/td_symbol_list.c b/nptl_db/td_symbol_list.c
index 6915ed78eb..b6c459f229 100644
--- a/nptl_db/td_symbol_list.c
+++ b/nptl_db/td_symbol_list.c
@@ -18,7 +18,6 @@
<http://www.gnu.org/licenses/>. */
#include <assert.h>
-#include <gnu/lib-names.h>
#include "thread_dbP.h"
static const char *symbol_list_arr[] =
@@ -41,12 +40,12 @@ td_symbol_list (void)
ps_err_e
-td_lookup (struct ps_prochandle *ps, int idx, psaddr_t *sym_addr)
+td_mod_lookup (struct ps_prochandle *ps, const char *mod,
+ int idx, psaddr_t *sym_addr)
{
ps_err_e result;
assert (idx >= 0 && idx < SYM_NUM_MESSAGES);
- result = ps_pglobal_lookup (ps, LIBPTHREAD_SO, symbol_list_arr[idx],
- sym_addr);
+ result = ps_pglobal_lookup (ps, mod, symbol_list_arr[idx], sym_addr);
return result;
}
diff --git a/nptl_db/td_thr_tlsbase.c b/nptl_db/td_thr_tlsbase.c
index 7092e31c5d..24a489ad46 100644
--- a/nptl_db/td_thr_tlsbase.c
+++ b/nptl_db/td_thr_tlsbase.c
@@ -17,14 +17,118 @@
<http://www.gnu.org/licenses/>. */
#include "thread_dbP.h"
+#include <link.h>
+/* Get the DTV slotinfo list head entry from the dynamic loader state
+ into *LISTHEAD. */
+static td_err_e
+dtv_slotinfo_list (td_thragent_t *ta,
+ psaddr_t *listhead)
+{
+ td_err_e err;
+ psaddr_t head;
+
+ if (ta->ta_addr__rtld_global == 0
+ && td_mod_lookup (ta->ph, LD_SO, SYM__rtld_global,
+ &ta->ta_addr__rtld_global) != PS_OK)
+ ta->ta_addr__rtld_global = (void*)-1;
+
+ if (ta->ta_addr__rtld_global != (void*)-1)
+ {
+ err = DB_GET_FIELD (head, ta, ta->ta_addr__rtld_global,
+ rtld_global, _dl_tls_dtv_slotinfo_list, 0);
+ if (err != TD_OK)
+ return err;
+ }
+ else
+ {
+ if (ta->ta_addr__dl_tls_dtv_slotinfo_list == 0
+ && td_mod_lookup (ta->ph, NULL, SYM__dl_tls_dtv_slotinfo_list,
+ &ta->ta_addr__dl_tls_dtv_slotinfo_list) != PS_OK)
+ return TD_ERR;
+
+ err = _td_fetch_value (ta, ta->ta_var__dl_tls_dtv_slotinfo_list,
+ SYM_DESC__dl_tls_dtv_slotinfo_list,
+ 0, ta->ta_addr__dl_tls_dtv_slotinfo_list, &head);
+ if (err != TD_OK)
+ return err;
+ }
+
+ *listhead = head;
+ return TD_OK;
+}
+
+/* Get the address of the DTV slotinfo entry for MODID into
+ *DTVSLOTINFO. */
+static td_err_e
+dtv_slotinfo (td_thragent_t *ta,
+ unsigned long int modid,
+ psaddr_t *dtvslotinfo)
+{
+ td_err_e err;
+ psaddr_t slot, temp;
+ size_t slbase = 0;
+
+ err = dtv_slotinfo_list (ta, &slot);
+ if (err != TD_OK)
+ return err;
+
+ while (slot)
+ {
+ /* Get the number of entries in this list entry's array. */
+ err = DB_GET_FIELD (temp, ta, slot, dtv_slotinfo_list, len, 0);
+ if (err != TD_OK)
+ return err;
+ size_t len = (uintptr_t)temp;
+
+ /* Did we find the list entry for modid? */
+ if (modid < slbase + len)
+ break;
+
+ /* We didn't, so get the next list entry. */
+ slbase += len;
+ err = DB_GET_FIELD (temp, ta, slot, dtv_slotinfo_list,
+ next, 0);
+ if (err != TD_OK)
+ return err;
+ slot = temp;
+ }
+
+ /* We reached the end of the list and found nothing. */
+ if (!slot)
+ return TD_ERR;
+
+ /* Take the slotinfo for modid from the list entry. */
+ err = DB_GET_FIELD_ADDRESS (temp, ta, slot, dtv_slotinfo_list,
+ slotinfo, modid - slbase);
+ if (err != TD_OK)
+ return err;
+ slot = temp;
+
+ *dtvslotinfo = slot;
+ return TD_OK;
+}
+
+/* Return in *BASE the base address of the TLS block for MODID within
+ TH.
+
+ It should return success and yield the correct pointer in any
+ circumstance where the TLS block for the module and thread
+ requested has already been initialized.
+
+ It should fail with TD_TLSDEFER only when the thread could not
+ possibly have observed any values in that TLS block. That way, the
+ debugger can fall back to showing initial values from the PT_TLS
+ segment (and refusing attempts to mutate) for the TD_TLSDEFER case,
+ and never fail to make the values the program will actually see
+ available to the user of the debugger. */
td_err_e
td_thr_tlsbase (const td_thrhandle_t *th,
unsigned long int modid,
psaddr_t *base)
{
td_err_e err;
- psaddr_t dtv, dtvslot, dtvptr;
+ psaddr_t dtv, dtvslot, dtvptr, temp;
if (modid < 1)
return TD_NOTLS;
@@ -50,11 +154,75 @@ td_thr_tlsbase (const td_thrhandle_t *th,
return TD_TLSDEFER;
}
+ err = dtv_slotinfo (th->th_ta_p, modid, &temp);
+ if (err != TD_OK)
+ return err;
+
+ psaddr_t slot;
+ err = DB_GET_STRUCT (slot, th->th_ta_p, temp, dtv_slotinfo);
+ if (err != TD_OK)
+ return err;
+
+ /* Take the link_map from the slotinfo. */
+ psaddr_t map;
+ err = DB_GET_FIELD_LOCAL (map, th->th_ta_p, slot, dtv_slotinfo, map, 0);
+ if (err != TD_OK)
+ return err;
+ if (!map)
+ return TD_ERR;
+
+ /* Ok, the modid is good, now find out what DTV generation it
+ requires. */
+ err = DB_GET_FIELD_LOCAL (temp, th->th_ta_p, slot, dtv_slotinfo, gen, 0);
+ if (err != TD_OK)
+ return err;
+ size_t modgen = (uintptr_t)temp;
+
/* Get the DTV pointer from the thread descriptor. */
err = DB_GET_FIELD (dtv, th->th_ta_p, pd, pthread, dtvp, 0);
if (err != TD_OK)
return err;
+ psaddr_t dtvgenloc;
+ /* Get the DTV generation count at dtv[0].counter. */
+ err = DB_GET_FIELD_ADDRESS (dtvgenloc, th->th_ta_p, dtv, dtv, dtv, 0);
+ if (err != TD_OK)
+ return err;
+ err = DB_GET_FIELD (temp, th->th_ta_p, dtvgenloc, dtv_t, counter, 0);
+ if (err != TD_OK)
+ return err;
+ size_t dtvgen = (uintptr_t)temp;
+
+ /* Is the DTV current enough? */
+ if (dtvgen < modgen)
+ {
+ try_static_tls:
+ /* If the module uses Static TLS, we're still good. */
+ err = DB_GET_FIELD (temp, th->th_ta_p, map, link_map, l_tls_offset, 0);
+ if (err != TD_OK)
+ return err;
+ ptrdiff_t tlsoff = (uintptr_t)temp;
+
+ if (tlsoff != FORCED_DYNAMIC_TLS_OFFSET
+ && tlsoff != NO_TLS_OFFSET)
+ {
+ psaddr_t tp = pd;
+
+#if TLS_TCB_AT_TP
+ dtvptr = tp - tlsoff;
+#elif TLS_DTV_AT_TP
+ dtvptr = tp + tlsoff + TLS_PRE_TCB_SIZE;
+#else
+# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+#endif
+
+ *base = dtvptr;
+ return TD_OK;
+ }
+
+ return TD_TLSDEFER;
+ }
+
/* Find the corresponding entry in the DTV. */
err = DB_GET_FIELD_ADDRESS (dtvslot, th->th_ta_p, dtv, dtv, dtv, modid);
if (err != TD_OK)
@@ -68,7 +236,7 @@ td_thr_tlsbase (const td_thrhandle_t *th,
/* It could be that the memory for this module is not allocated for
the given thread. */
if ((uintptr_t) dtvptr & 1)
- return TD_TLSDEFER;
+ goto try_static_tls;
*base = dtvptr;
return TD_OK;
diff --git a/nptl_db/thread_dbP.h b/nptl_db/thread_dbP.h
index 4b59ce68ab..445c797758 100644
--- a/nptl_db/thread_dbP.h
+++ b/nptl_db/thread_dbP.h
@@ -29,6 +29,7 @@
#include "thread_db.h"
#include "../nptl/pthreadP.h" /* This is for *_BITMASK only. */
#include <list.h>
+#include <gnu/lib-names.h>
/* Indeces for the symbol names. */
enum
@@ -139,11 +140,11 @@ ta_ok (const td_thragent_t *ta)
}
-/* Internal wrapper around ps_pglobal_lookup. */
-extern ps_err_e td_lookup (struct ps_prochandle *ps,
- int idx, psaddr_t *sym_addr) attribute_hidden;
-
-
+/* Internal wrappers around ps_pglobal_lookup. */
+extern ps_err_e td_mod_lookup (struct ps_prochandle *ps, const char *modname,
+ int idx, psaddr_t *sym_addr) attribute_hidden;
+#define td_lookup(ps, idx, sym_addr) \
+ td_mod_lookup ((ps), LIBPTHREAD_SO, (idx), (sym_addr))
/* Store in psaddr_t VAR the address of inferior's symbol NAME. */