From db1ff28b60f8886b8d7c634f1db2f939ba47a13c Mon Sep 17 00:00:00 2001 From: Jan Kratochvil Date: Wed, 15 Jul 2015 20:27:32 +0200 Subject: Revert the previous 7 commits of: Validate binary before use ddc98fbf2fd9e244a215a4d09e559180dc573a14 Create empty nat/linux-maps.[ch] and common/target-utils.[ch] 6e5b4429db0d66e2d0b27e1bcfe4709f3dae73ed Move gdb_regex* to common/ f7af1fcd759fa126612018a5916cf808df7bb8bc Prepare linux_find_memory_regions_full & co. for move 9904185cfde13d6c6849f1f042c8e3b74974cf08 Move linux_find_memory_regions_full & co. 700ca40f6fc1addd7238f4ab57f76c095ad3c99f gdbserver build-id attribute generator ca5268b6be265580b91ef75c1a1a9815f581ae42 Validate symbol file using build-id 0a94970d663a053c523f23ac0d71deb25a77f709 Tests for validate symbol file using build-id gdb/ChangeLog 2015-07-15 Jan Kratochvil Revert the previous 6 commits: Create empty nat/linux-maps.[ch] and common/target-utils.[ch]. Move gdb_regex* to common/ Prepare linux_find_memory_regions_full & co. for move Move linux_find_memory_regions_full & co. gdbserver build-id attribute generator Validate symbol file using build-id gdb/gdbserver/ChangeLog 2015-07-15 Jan Kratochvil Revert the previous 3 commits: Move gdb_regex* to common/ Move linux_find_memory_regions_full & co. gdbserver build-id attribute generator gdb/doc/ChangeLog 2015-07-15 Jan Kratochvil Revert the previous 2 commits: gdbserver build-id attribute generator Validate symbol file using build-id gdb/testsuite/ChangeLog 2015-07-15 Jan Kratochvil Revert the previous commit: Tests for validate symbol file using build-id. --- gdb/nat/linux-maps.c | 493 --------------------------------------------------- gdb/nat/linux-maps.h | 64 ------- 2 files changed, 557 deletions(-) delete mode 100644 gdb/nat/linux-maps.c delete mode 100644 gdb/nat/linux-maps.h (limited to 'gdb/nat') diff --git a/gdb/nat/linux-maps.c b/gdb/nat/linux-maps.c deleted file mode 100644 index ef3da6a..0000000 --- a/gdb/nat/linux-maps.c +++ /dev/null @@ -1,493 +0,0 @@ -/* Linux-specific memory maps manipulation routines. - Copyright (C) 2015 Free Software Foundation, Inc. - - This file is part of GDB. - - 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 3 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, see . */ - -#include "common-defs.h" -#include "linux-maps.h" -#include -#include "target/target-utils.h" -#include "gdb_regex.h" -#include "target/target.h" - -/* This struct is used to map flags found in the "VmFlags:" field (in - the /proc//smaps file). */ - -struct smaps_vmflags - { - /* Zero if this structure has not been initialized yet. It - probably means that the Linux kernel being used does not emit - the "VmFlags:" field on "/proc/PID/smaps". */ - - unsigned int initialized_p : 1; - - /* Memory mapped I/O area (VM_IO, "io"). */ - - unsigned int io_page : 1; - - /* Area uses huge TLB pages (VM_HUGETLB, "ht"). */ - - unsigned int uses_huge_tlb : 1; - - /* Do not include this memory region on the coredump (VM_DONTDUMP, "dd"). */ - - unsigned int exclude_coredump : 1; - - /* Is this a MAP_SHARED mapping (VM_SHARED, "sh"). */ - - unsigned int shared_mapping : 1; - }; - -/* Service function for corefiles and info proc. */ - -void -read_mapping (const char *line, - ULONGEST *addr, ULONGEST *endaddr, - const char **permissions, size_t *permissions_len, - ULONGEST *offset, - const char **device, size_t *device_len, - ULONGEST *inode, - const char **filename) -{ - const char *p = line; - - *addr = strtoulst (p, &p, 16); - if (*p == '-') - p++; - *endaddr = strtoulst (p, &p, 16); - - p = skip_spaces_const (p); - *permissions = p; - while (*p && !isspace (*p)) - p++; - *permissions_len = p - *permissions; - - *offset = strtoulst (p, &p, 16); - - p = skip_spaces_const (p); - *device = p; - while (*p && !isspace (*p)) - p++; - *device_len = p - *device; - - *inode = strtoulst (p, &p, 10); - - p = skip_spaces_const (p); - *filename = p; -} - -/* Helper function to decode the "VmFlags" field in /proc/PID/smaps. - - This function was based on the documentation found on - , on the Linux kernel. - - Linux kernels before commit - 834f82e2aa9a8ede94b17b656329f850c1471514 (3.10) do not have this - field on smaps. */ - -static void -decode_vmflags (char *p, struct smaps_vmflags *v) -{ - char *saveptr = NULL; - const char *s; - - v->initialized_p = 1; - p = skip_to_space (p); - p = skip_spaces (p); - - for (s = strtok_r (p, " ", &saveptr); - s != NULL; - s = strtok_r (NULL, " ", &saveptr)) - { - if (strcmp (s, "io") == 0) - v->io_page = 1; - else if (strcmp (s, "ht") == 0) - v->uses_huge_tlb = 1; - else if (strcmp (s, "dd") == 0) - v->exclude_coredump = 1; - else if (strcmp (s, "sh") == 0) - v->shared_mapping = 1; - } -} - -/* Return 1 if the memory mapping is anonymous, 0 otherwise. - - FILENAME is the name of the file present in the first line of the - memory mapping, in the "/proc/PID/smaps" output. For example, if - the first line is: - - 7fd0ca877000-7fd0d0da0000 r--p 00000000 fd:02 2100770 /path/to/file - - Then FILENAME will be "/path/to/file". */ - -static int -mapping_is_anonymous_p (const char *filename) -{ - static regex_t dev_zero_regex, shmem_file_regex, file_deleted_regex; - static int init_regex_p = 0; - - if (!init_regex_p) - { - struct cleanup *c = make_cleanup (null_cleanup, NULL); - - /* Let's be pessimistic and assume there will be an error while - compiling the regex'es. */ - init_regex_p = -1; - - /* DEV_ZERO_REGEX matches "/dev/zero" filenames (with or - without the "(deleted)" string in the end). We know for - sure, based on the Linux kernel code, that memory mappings - whose associated filename is "/dev/zero" are guaranteed to be - MAP_ANONYMOUS. */ - compile_rx_or_error (&dev_zero_regex, "^/dev/zero\\( (deleted)\\)\\?$", - _("Could not compile regex to match /dev/zero " - "filename")); - /* SHMEM_FILE_REGEX matches "/SYSV%08x" filenames (with or - without the "(deleted)" string in the end). These filenames - refer to shared memory (shmem), and memory mappings - associated with them are MAP_ANONYMOUS as well. */ - compile_rx_or_error (&shmem_file_regex, - "^/\\?SYSV[0-9a-fA-F]\\{8\\}\\( (deleted)\\)\\?$", - _("Could not compile regex to match shmem " - "filenames")); - /* FILE_DELETED_REGEX is a heuristic we use to try to mimic the - Linux kernel's 'n_link == 0' code, which is responsible to - decide if it is dealing with a 'MAP_SHARED | MAP_ANONYMOUS' - mapping. In other words, if FILE_DELETED_REGEX matches, it - does not necessarily mean that we are dealing with an - anonymous shared mapping. However, there is no easy way to - detect this currently, so this is the best approximation we - have. - - As a result, GDB will dump readonly pages of deleted - executables when using the default value of coredump_filter - (0x33), while the Linux kernel will not dump those pages. - But we can live with that. */ - compile_rx_or_error (&file_deleted_regex, " (deleted)$", - _("Could not compile regex to match " - "' (deleted)'")); - /* We will never release these regexes, so just discard the - cleanups. */ - discard_cleanups (c); - - /* If we reached this point, then everything succeeded. */ - init_regex_p = 1; - } - - if (init_regex_p == -1) - { - const char deleted[] = " (deleted)"; - size_t del_len = sizeof (deleted) - 1; - size_t filename_len = strlen (filename); - - /* There was an error while compiling the regex'es above. In - order to try to give some reliable information to the caller, - we just try to find the string " (deleted)" in the filename. - If we managed to find it, then we assume the mapping is - anonymous. */ - return (filename_len >= del_len - && strcmp (filename + filename_len - del_len, deleted) == 0); - } - - if (*filename == '\0' - || regexec (&dev_zero_regex, filename, 0, NULL, 0) == 0 - || regexec (&shmem_file_regex, filename, 0, NULL, 0) == 0 - || regexec (&file_deleted_regex, filename, 0, NULL, 0) == 0) - return 1; - - return 0; -} - -/* Return 0 if the memory mapping (which is related to FILTERFLAGS, V, - MAYBE_PRIVATE_P, and MAPPING_ANONYMOUS_P) should not be dumped, or - greater than 0 if it should. - - In a nutshell, this is the logic that we follow in order to decide - if a mapping should be dumped or not. - - - If the mapping is associated to a file whose name ends with - " (deleted)", or if the file is "/dev/zero", or if it is - "/SYSV%08x" (shared memory), or if there is no file associated - with it, or if the AnonHugePages: or the Anonymous: fields in the - /proc/PID/smaps have contents, then GDB considers this mapping to - be anonymous. Otherwise, GDB considers this mapping to be a - file-backed mapping (because there will be a file associated with - it). - - It is worth mentioning that, from all those checks described - above, the most fragile is the one to see if the file name ends - with " (deleted)". This does not necessarily mean that the - mapping is anonymous, because the deleted file associated with - the mapping may have been a hard link to another file, for - example. The Linux kernel checks to see if "i_nlink == 0", but - GDB cannot easily (and normally) do this check (iff running as - root, it could find the mapping in /proc/PID/map_files/ and - determine whether there still are other hard links to the - inode/file). Therefore, we made a compromise here, and we assume - that if the file name ends with " (deleted)", then the mapping is - indeed anonymous. FWIW, this is something the Linux kernel could - do better: expose this information in a more direct way. - - - If we see the flag "sh" in the "VmFlags:" field (in - /proc/PID/smaps), then certainly the memory mapping is shared - (VM_SHARED). If we have access to the VmFlags, and we don't see - the "sh" there, then certainly the mapping is private. However, - Linux kernels before commit - 834f82e2aa9a8ede94b17b656329f850c1471514 (3.10) do not have the - "VmFlags:" field; in that case, we use another heuristic: if we - see 'p' in the permission flags, then we assume that the mapping - is private, even though the presence of the 's' flag there would - mean VM_MAYSHARE, which means the mapping could still be private. - This should work OK enough, however. */ - -static int -dump_mapping_p (enum filterflags filterflags, const struct smaps_vmflags *v, - int maybe_private_p, int mapping_anon_p, int mapping_file_p, - const char *filename) -{ - /* Initially, we trust in what we received from our caller. This - value may not be very precise (i.e., it was probably gathered - from the permission line in the /proc/PID/smaps list, which - actually refers to VM_MAYSHARE, and not VM_SHARED), but it is - what we have until we take a look at the "VmFlags:" field - (assuming that the version of the Linux kernel being used - supports it, of course). */ - int private_p = maybe_private_p; - - /* We always dump vDSO and vsyscall mappings, because it's likely that - there'll be no file to read the contents from at core load time. - The kernel does the same. */ - if (strcmp ("[vdso]", filename) == 0 - || strcmp ("[vsyscall]", filename) == 0) - return 1; - - if (v->initialized_p) - { - /* We never dump I/O mappings. */ - if (v->io_page) - return 0; - - /* Check if we should exclude this mapping. */ - if (v->exclude_coredump) - return 0; - - /* Update our notion of whether this mapping is shared or - private based on a trustworthy value. */ - private_p = !v->shared_mapping; - - /* HugeTLB checking. */ - if (v->uses_huge_tlb) - { - if ((private_p && (filterflags & COREFILTER_HUGETLB_PRIVATE)) - || (!private_p && (filterflags & COREFILTER_HUGETLB_SHARED))) - return 1; - - return 0; - } - } - - if (private_p) - { - if (mapping_anon_p && mapping_file_p) - { - /* This is a special situation. It can happen when we see a - mapping that is file-backed, but that contains anonymous - pages. */ - return ((filterflags & COREFILTER_ANON_PRIVATE) != 0 - || (filterflags & COREFILTER_MAPPED_PRIVATE) != 0); - } - else if (mapping_anon_p) - return (filterflags & COREFILTER_ANON_PRIVATE) != 0; - else - return (filterflags & COREFILTER_MAPPED_PRIVATE) != 0; - } - else - { - if (mapping_anon_p && mapping_file_p) - { - /* This is a special situation. It can happen when we see a - mapping that is file-backed, but that contains anonymous - pages. */ - return ((filterflags & COREFILTER_ANON_SHARED) != 0 - || (filterflags & COREFILTER_MAPPED_SHARED) != 0); - } - else if (mapping_anon_p) - return (filterflags & COREFILTER_ANON_SHARED) != 0; - else - return (filterflags & COREFILTER_MAPPED_SHARED) != 0; - } -} - -/* List memory regions in the inferior PID matched to FILTERFLAGS for - a corefile. Call FUNC with FUNC_DATA for each such region. Return - immediately with the value returned by FUNC if it is non-zero. - *MEMORY_TO_FREE_PTR should be registered to be freed automatically if - called FUNC throws an exception. MEMORY_TO_FREE_PTR can be also - passed as NULL if it is not used. Return -1 if error occurs, 0 if - all memory regions have been processed or return the value from FUNC - if FUNC returns non-zero. */ - -int -linux_find_memory_regions_full (pid_t pid, enum filterflags filterflags, - linux_find_memory_region_ftype *func, - void *func_data) -{ - char mapsfilename[100]; - char *data; - - xsnprintf (mapsfilename, sizeof mapsfilename, "/proc/%d/smaps", pid); - data = target_fileio_read_stralloc (NULL, mapsfilename); - if (data == NULL) - { - /* Older Linux kernels did not support /proc/PID/smaps. */ - xsnprintf (mapsfilename, sizeof mapsfilename, "/proc/%d/maps", pid); - data = target_fileio_read_stralloc (NULL, mapsfilename); - } - - if (data != NULL) - { - struct cleanup *cleanup = make_cleanup (xfree, data); - char *line, *t; - int retval = 0; - - line = strtok_r (data, "\n", &t); - while (line != NULL) - { - ULONGEST addr, endaddr, offset, inode; - const char *permissions, *device, *filename; - struct smaps_vmflags v; - size_t permissions_len, device_len; - int read, write, exec, priv; - int has_anonymous = 0; - int should_dump_p = 0; - int mapping_anon_p; - int mapping_file_p; - - memset (&v, 0, sizeof (v)); - read_mapping (line, &addr, &endaddr, &permissions, &permissions_len, - &offset, &device, &device_len, &inode, &filename); - mapping_anon_p = mapping_is_anonymous_p (filename); - /* If the mapping is not anonymous, then we can consider it - to be file-backed. These two states (anonymous or - file-backed) seem to be exclusive, but they can actually - coexist. For example, if a file-backed mapping has - "Anonymous:" pages (see more below), then the Linux - kernel will dump this mapping when the user specified - that she only wants anonymous mappings in the corefile - (*even* when she explicitly disabled the dumping of - file-backed mappings). */ - mapping_file_p = !mapping_anon_p; - - /* Decode permissions. */ - read = (memchr (permissions, 'r', permissions_len) != 0); - write = (memchr (permissions, 'w', permissions_len) != 0); - exec = (memchr (permissions, 'x', permissions_len) != 0); - /* 'private' here actually means VM_MAYSHARE, and not - VM_SHARED. In order to know if a mapping is really - private or not, we must check the flag "sh" in the - VmFlags field. This is done by decode_vmflags. However, - if we are using a Linux kernel released before the commit - 834f82e2aa9a8ede94b17b656329f850c1471514 (3.10), we will - not have the VmFlags there. In this case, there is - really no way to know if we are dealing with VM_SHARED, - so we just assume that VM_MAYSHARE is enough. */ - priv = memchr (permissions, 'p', permissions_len) != 0; - - /* Try to detect if region should be dumped by parsing smaps - counters. */ - for (line = strtok_r (NULL, "\n", &t); - line != NULL && line[0] >= 'A' && line[0] <= 'Z'; - line = strtok_r (NULL, "\n", &t)) - { - char keyword[64 + 1]; - - if (sscanf (line, "%64s", keyword) != 1) - { - warning (_("Error parsing {s,}maps file '%s'"), mapsfilename); - break; - } - - if (strcmp (keyword, "Anonymous:") == 0) - { - /* Older Linux kernels did not support the - "Anonymous:" counter. Check it here. */ - has_anonymous = 1; - } - else if (strcmp (keyword, "VmFlags:") == 0) - decode_vmflags (line, &v); - - if (strcmp (keyword, "AnonHugePages:") == 0 - || strcmp (keyword, "Anonymous:") == 0) - { - unsigned long number; - - if (sscanf (line, "%*s%lu", &number) != 1) - { - warning (_("Error parsing {s,}maps file '%s' number"), - mapsfilename); - break; - } - if (number > 0) - { - /* Even if we are dealing with a file-backed - mapping, if it contains anonymous pages we - consider it to be *also* an anonymous - mapping, because this is what the Linux - kernel does: - - // Dump segments that have been written to. - if (vma->anon_vma && FILTER(ANON_PRIVATE)) - goto whole; - - Note that if the mapping is already marked as - file-backed (i.e., mapping_file_p is - non-zero), then this is a special case, and - this mapping will be dumped either when the - user wants to dump file-backed *or* anonymous - mappings. */ - mapping_anon_p = 1; - } - } - } - - if (has_anonymous) - should_dump_p = dump_mapping_p (filterflags, &v, priv, - mapping_anon_p, mapping_file_p, - filename); - else - { - /* Older Linux kernels did not support the "Anonymous:" counter. - If it is missing, we can't be sure - dump all the pages. */ - should_dump_p = 1; - } - - /* Invoke the callback function to create the corefile segment. */ - if (should_dump_p) - retval = func (addr, endaddr - addr, offset, inode, - read, write, exec, - 1, /* MODIFIED is true because we want to dump the - mapping. */ - filename, func_data); - if (retval != 0) - break; - } - - do_cleanups (cleanup); - return retval; - } - - return -1; -} diff --git a/gdb/nat/linux-maps.h b/gdb/nat/linux-maps.h deleted file mode 100644 index 7e10d65..0000000 --- a/gdb/nat/linux-maps.h +++ /dev/null @@ -1,64 +0,0 @@ -/* Linux-specific memory maps manipulation routines. - Copyright (C) 2015 Free Software Foundation, Inc. - - This file is part of GDB. - - 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 3 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, see . */ - -#ifndef NAT_LINUX_MAPS_H -#define NAT_LINUX_MAPS_H - -extern void - read_mapping (const char *line, - ULONGEST *addr, ULONGEST *endaddr, - const char **permissions, size_t *permissions_len, - ULONGEST *offset, - const char **device, size_t *device_len, - ULONGEST *inode, - const char **filename); - -/* Callback function for linux_find_memory_regions_full. If it returns - non-zero linux_find_memory_regions_full returns immediately with that - value. */ - -typedef int linux_find_memory_region_ftype (ULONGEST vaddr, ULONGEST size, - ULONGEST offset, ULONGEST inode, - int read, int write, - int exec, int modified, - const char *filename, - void *data); - -/* This enum represents the values that the user can choose when - informing the Linux kernel about which memory mappings will be - dumped in a corefile. They are described in the file - Documentation/filesystems/proc.txt, inside the Linux kernel - tree. */ - -enum filterflags - { - COREFILTER_ANON_PRIVATE = 1 << 0, - COREFILTER_ANON_SHARED = 1 << 1, - COREFILTER_MAPPED_PRIVATE = 1 << 2, - COREFILTER_MAPPED_SHARED = 1 << 3, - COREFILTER_ELF_HEADERS = 1 << 4, - COREFILTER_HUGETLB_PRIVATE = 1 << 5, - COREFILTER_HUGETLB_SHARED = 1 << 6, - }; - -extern int - linux_find_memory_regions_full (pid_t pid, enum filterflags filterflags, - linux_find_memory_region_ftype *func, - void *func_data); - -#endif /* NAT_LINUX_MAPS_H */ -- cgit v1.1