summaryrefslogtreecommitdiffstats
path: root/src/libdwfl/linux-proc-maps.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libdwfl/linux-proc-maps.c')
-rw-r--r--src/libdwfl/linux-proc-maps.c422
1 files changed, 0 insertions, 422 deletions
diff --git a/src/libdwfl/linux-proc-maps.c b/src/libdwfl/linux-proc-maps.c
deleted file mode 100644
index d0858342..00000000
--- a/src/libdwfl/linux-proc-maps.c
+++ /dev/null
@@ -1,422 +0,0 @@
-/* Standard libdwfl callbacks for debugging a live Linux process.
- Copyright (C) 2005-2010, 2013, 2014 Red Hat, Inc.
- This file is part of elfutils.
-
- This file is free software; you can redistribute it and/or modify
- it under the terms of either
-
- * the GNU Lesser General Public License as published by the Free
- Software Foundation; either version 3 of the License, or (at
- your option) any later version
-
- or
-
- * 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
-
- or both in parallel, as here.
-
- elfutils 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 copies of the GNU General Public License and
- the GNU Lesser General Public License along with this program. If
- not, see <http://www.gnu.org/licenses/>. */
-
-#include "libdwflP.h"
-#include <inttypes.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <errno.h>
-#include <stdio.h>
-#include <stdio_ext.h>
-#include <stdbool.h>
-#include <string.h>
-#include <stdlib.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <assert.h>
-#include <endian.h>
-#include "system.h"
-
-
-#define PROCMAPSFMT "/proc/%d/maps"
-#define PROCMEMFMT "/proc/%d/mem"
-#define PROCAUXVFMT "/proc/%d/auxv"
-#define PROCEXEFMT "/proc/%d/exe"
-
-
-/* Return ELFCLASS64 or ELFCLASS32 for the main ELF executable. Return
- ELFCLASSNONE for an error. */
-
-static unsigned char
-get_pid_class (pid_t pid)
-{
- char *fname;
- if (asprintf (&fname, PROCEXEFMT, pid) < 0)
- return ELFCLASSNONE;
-
- int fd = open64 (fname, O_RDONLY);
- free (fname);
- if (fd < 0)
- return ELFCLASSNONE;
-
- unsigned char buf[EI_CLASS + 1];
- ssize_t nread = pread_retry (fd, &buf, sizeof buf, 0);
- close (fd);
- if (nread != sizeof buf || buf[EI_MAG0] != ELFMAG0
- || buf[EI_MAG1] != ELFMAG1 || buf[EI_MAG2] != ELFMAG2
- || buf[EI_MAG3] != ELFMAG3
- || (buf[EI_CLASS] != ELFCLASS64 && buf[EI_CLASS] != ELFCLASS32))
- return ELFCLASSNONE;
-
- return buf[EI_CLASS];
-}
-
-/* Search /proc/PID/auxv for the AT_SYSINFO_EHDR tag.
-
- It would be easiest to call get_pid_class and parse everything according to
- the 32-bit or 64-bit class. But this would bring the overhead of syscalls
- to open and read the "/proc/%d/exe" file.
-
- Therefore this function tries to parse the "/proc/%d/auxv" content both
- ways, as if it were the 32-bit format and also if it were the 64-bit format.
- Only if it gives some valid data in both cases get_pid_class gets called.
- In most cases only one of the format bit sizes gives valid data and the
- get_pid_class call overhead can be saved. */
-
-static int
-grovel_auxv (pid_t pid, Dwfl *dwfl, GElf_Addr *sysinfo_ehdr)
-{
- char *fname;
- if (asprintf (&fname, PROCAUXVFMT, pid) < 0)
- return ENOMEM;
-
- int fd = open64 (fname, O_RDONLY);
- free (fname);
- if (fd < 0)
- return errno == ENOENT ? 0 : errno;
-
- GElf_Addr sysinfo_ehdr64 = 0;
- GElf_Addr sysinfo_ehdr32 = 0;
- GElf_Addr segment_align64 = dwfl->segment_align;
- GElf_Addr segment_align32 = dwfl->segment_align;
- off_t offset = 0;
- ssize_t nread;
- union
- {
- Elf64_auxv_t a64[64];
- Elf32_auxv_t a32[128];
- } d;
- do
- {
- eu_static_assert (sizeof d.a64 == sizeof d.a32);
- nread = pread_retry (fd, d.a64, sizeof d.a64, offset);
- if (nread < 0)
- {
- int ret = errno;
- close (fd);
- return ret;
- }
- for (size_t a32i = 0; a32i < nread / sizeof d.a32[0]; a32i++)
- {
- const Elf32_auxv_t *a32 = d.a32 + a32i;
- switch (a32->a_type)
- {
- case AT_SYSINFO_EHDR:
- sysinfo_ehdr32 = a32->a_un.a_val;
- break;
- case AT_PAGESZ:
- segment_align32 = a32->a_un.a_val;
- break;
- }
- }
- for (size_t a64i = 0; a64i < nread / sizeof d.a64[0]; a64i++)
- {
- const Elf64_auxv_t *a64 = d.a64 + a64i;
- switch (a64->a_type)
- {
- case AT_SYSINFO_EHDR:
- sysinfo_ehdr64 = a64->a_un.a_val;
- break;
- case AT_PAGESZ:
- segment_align64 = a64->a_un.a_val;
- break;
- }
- }
- offset += nread;
- }
- while (nread == sizeof d.a64);
-
- close (fd);
-
- bool valid64 = sysinfo_ehdr64 != 0 || segment_align64 != dwfl->segment_align;
- bool valid32 = sysinfo_ehdr32 != 0 || segment_align32 != dwfl->segment_align;
-
- unsigned char pid_class = ELFCLASSNONE;
- if (valid64 && valid32)
- pid_class = get_pid_class (pid);
-
- if (pid_class == ELFCLASS64 || (valid64 && ! valid32))
- {
- *sysinfo_ehdr = sysinfo_ehdr64;
- dwfl->segment_align = segment_align64;
- return 0;
- }
- if (pid_class == ELFCLASS32 || (! valid64 && valid32))
- {
- *sysinfo_ehdr = sysinfo_ehdr32;
- dwfl->segment_align = segment_align32;
- return 0;
- }
- return ENOEXEC;
-}
-
-static int
-proc_maps_report (Dwfl *dwfl, FILE *f, GElf_Addr sysinfo_ehdr, pid_t pid)
-{
- unsigned int last_dmajor = -1, last_dminor = -1;
- uint64_t last_ino = -1;
- char *last_file = NULL;
- Dwarf_Addr low = 0, high = 0;
-
- inline bool report (void)
- {
- if (last_file != NULL)
- {
- Dwfl_Module *mod = INTUSE(dwfl_report_module) (dwfl, last_file,
- low, high);
- free (last_file);
- last_file = NULL;
- if (unlikely (mod == NULL))
- return true;
- }
- return false;
- }
-
- char *line = NULL;
- size_t linesz;
- ssize_t len;
- while ((len = getline (&line, &linesz, f)) > 0)
- {
- if (line[len - 1] == '\n')
- line[len - 1] = '\0';
-
- Dwarf_Addr start, end, offset;
- unsigned int dmajor, dminor;
- uint64_t ino;
- int nread = -1;
- if (sscanf (line, "%" PRIx64 "-%" PRIx64 " %*s %" PRIx64
- " %x:%x %" PRIi64 " %n",
- &start, &end, &offset, &dmajor, &dminor, &ino, &nread) < 6
- || nread <= 0)
- {
- free (line);
- return ENOEXEC;
- }
-
- /* If this is the special mapping AT_SYSINFO_EHDR pointed us at,
- report the last one and then this special one. */
- if (start == sysinfo_ehdr && start != 0)
- {
- if (report ())
- {
- bad_report:
- free (line);
- return -1;
- }
-
- low = start;
- high = end;
- if (asprintf (&last_file, "[vdso: %d]", (int) pid) < 0
- || report ())
- goto bad_report;
- }
-
- char *file = line + nread + strspn (line + nread, " \t");
- if (file[0] != '/' || (ino == 0 && dmajor == 0 && dminor == 0))
- /* This line doesn't indicate a file mapping. */
- continue;
-
- if (last_file != NULL
- && ino == last_ino && dmajor == last_dmajor && dminor == last_dminor)
- {
- /* This is another portion of the same file's mapping. */
- if (strcmp (last_file, file) != 0)
- goto bad_report;
- high = end;
- }
- else
- {
- /* This is a different file mapping. Report the last one. */
- if (report ())
- goto bad_report;
- low = start;
- high = end;
- last_file = strdup (file);
- last_ino = ino;
- last_dmajor = dmajor;
- last_dminor = dminor;
- }
- }
- free (line);
-
- int result = ferror_unlocked (f) ? errno : feof_unlocked (f) ? 0 : ENOEXEC;
-
- /* Report the final one. */
- bool lose = report ();
-
- return result != 0 ? result : lose ? -1 : 0;
-}
-
-int
-dwfl_linux_proc_maps_report (Dwfl *dwfl, FILE *f)
-{
- return proc_maps_report (dwfl, f, 0, 0);
-}
-INTDEF (dwfl_linux_proc_maps_report)
-
-int
-dwfl_linux_proc_report (Dwfl *dwfl, pid_t pid)
-{
- if (dwfl == NULL)
- return -1;
-
- /* We'll notice the AT_SYSINFO_EHDR address specially when we hit it. */
- GElf_Addr sysinfo_ehdr = 0;
- int result = grovel_auxv (pid, dwfl, &sysinfo_ehdr);
- if (result != 0)
- return result;
-
- char *fname;
- if (asprintf (&fname, PROCMAPSFMT, pid) < 0)
- return ENOMEM;
-
- FILE *f = fopen (fname, "r");
- free (fname);
- if (f == NULL)
- return errno;
-
- (void) __fsetlocking (f, FSETLOCKING_BYCALLER);
-
- result = proc_maps_report (dwfl, f, sysinfo_ehdr, pid);
-
- fclose (f);
-
- return result;
-}
-INTDEF (dwfl_linux_proc_report)
-
-static ssize_t
-read_proc_memory (void *arg, void *data, GElf_Addr address,
- size_t minread, size_t maxread)
-{
- const int fd = *(const int *) arg;
- ssize_t nread = pread64 (fd, data, maxread, (off64_t) address);
- /* Some kernels don't actually let us do this read, ignore those errors. */
- if (nread < 0 && (errno == EINVAL || errno == EPERM))
- return 0;
- if (nread > 0 && (size_t) nread < minread)
- nread = 0;
- return nread;
-}
-
-extern Elf *elf_from_remote_memory (GElf_Addr ehdr_vma,
- GElf_Xword pagesize,
- GElf_Addr *loadbasep,
- ssize_t (*read_memory) (void *arg,
- void *data,
- GElf_Addr address,
- size_t minread,
- size_t maxread),
- void *arg);
-
-
-/* Dwfl_Callbacks.find_elf */
-
-int
-dwfl_linux_proc_find_elf (Dwfl_Module *mod __attribute__ ((unused)),
- void **userdata __attribute__ ((unused)),
- const char *module_name, Dwarf_Addr base,
- char **file_name, Elf **elfp)
-{
- int pid = -1;
- if (module_name[0] == '/')
- {
- /* When this callback is used together with dwfl_linux_proc_report
- then we might see mappings of special character devices. Make
- sure we only open and return regular files. Special devices
- might hang on open or read. (deleted) files are super special.
- The image might come from memory if we are attached. */
- struct stat sb;
- if (stat (module_name, &sb) == -1 || (sb.st_mode & S_IFMT) != S_IFREG)
- {
- if (strcmp (strrchr (module_name, ' ') ?: "", " (deleted)") == 0)
- pid = INTUSE(dwfl_pid) (mod->dwfl);
- else
- return -1;
- }
-
- if (pid == -1)
- {
- int fd = open64 (module_name, O_RDONLY);
- if (fd >= 0)
- {
- *file_name = strdup (module_name);
- if (*file_name == NULL)
- {
- close (fd);
- return ENOMEM;
- }
- }
- return fd;
- }
- }
-
- if (pid != -1 || sscanf (module_name, "[vdso: %d]", &pid) == 1)
- {
- /* Special case for in-memory ELF image. */
-
- bool detach = false;
- bool tid_was_stopped = false;
- struct __libdwfl_pid_arg *pid_arg = __libdwfl_get_pid_arg (mod->dwfl);
- if (pid_arg != NULL && ! pid_arg->assume_ptrace_stopped)
- {
- /* If any thread is already attached we are fine. Read
- through that thread. It doesn't have to be the main
- thread pid. */
- pid_t tid = pid_arg->tid_attached;
- if (tid != 0)
- pid = tid;
- else
- detach = __libdwfl_ptrace_attach (pid, &tid_was_stopped);
- }
-
- char *fname;
- if (asprintf (&fname, PROCMEMFMT, pid) < 0)
- goto detach;
-
- int fd = open64 (fname, O_RDONLY);
- free (fname);
- if (fd < 0)
- goto detach;
-
- *elfp = elf_from_remote_memory (base, getpagesize (), NULL,
- &read_proc_memory, &fd);
-
- close (fd);
-
- *file_name = NULL;
-
- detach:
- if (detach)
- __libdwfl_ptrace_detach (pid, tid_was_stopped);
- return -1;
- }
-
- return -1;
-}
-INTDEF (dwfl_linux_proc_find_elf)
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-23 01:11:37 +0000