diff options
| author | Pedro Alves <palves@redhat.com> | 2017-10-17 12:41:00 +0100 |
|---|---|---|
| committer | Pedro Alves <palves@redhat.com> | 2017-10-17 12:41:00 +0100 |
| commit | 7b7009999ab8daac9db776c850b7df6e1f586334 (patch) | |
| tree | 5423e586e7d59f5072bc3d50246ad493ee957df1 | |
| parent | d3037ba6a398d37585b3d34ff9ed439848ba98a1 (diff) | |
| download | binutils-gdb-7b7009999ab8daac9db776c850b7df6e1f586334.tar.gz | |
Fix double-free corruption
Fixes a double-free regression introduced by commit b7b030adc405
("Return unique_xmalloc_ptr from target_read_stralloc"):
gdb.sum:
Running src/gdb/testsuite/gdb.base/catch-syscall.exp ...
ERROR: Process no longer exists
Valgrind shows:
(gdb) catch syscall
==3687== Thread 1:
==3687== Invalid free() / delete / delete[] / realloc()
==3687== at 0x4C29CF0: free (vg_replace_malloc.c:530)
==3687== by 0x610862: xfree(void*) (common-utils.c:101)
==3687== by 0x440D5D: gdb::xfree_deleter<char>::operator()(char*) const (gdb_unique_ptr.h:34)
==3687== by 0x446CC6: std::unique_ptr<char, gdb::xfree_deleter<char> >::reset(char*) (unique_ptr.h:344)
==3687== by 0x81BE50: xml_fetch_content_from_file(char const*, void*) (xml-support.c:1042)
==3687== by 0x81DA86: xml_init_syscalls_info(char const*) (xml-syscall.c:366)
==3687== by 0x81DBDD: init_syscalls_info(gdbarch*) (xml-syscall.c:398)
==3687== by 0x81E131: get_syscall_by_number(gdbarch*, int, syscall*) (xml-syscall.c:599)
==3687== by 0x5BE86F: catch_syscall_command_1(char*, int, cmd_list_element*) (break-catch-syscall.c:481)
==3687== by 0x4B46B1: do_sfunc(cmd_list_element*, char*, int) (cli-decode.c:138)
==3687== by 0x4B76B8: cmd_func(cmd_list_element*, char*, int) (cli-decode.c:1952)
==3687== by 0x7E91C7: execute_command(char*, int) (top.c:615)
==3687== Address 0x14332ae0 is 0 bytes inside a block of size 4,096 free'd
==3687== at 0x4C2AB8B: realloc (vg_replace_malloc.c:785)
==3687== by 0x610792: xrealloc (common-utils.c:62)
==3687== by 0x81BE3E: xml_fetch_content_from_file(char const*, void*) (xml-support.c:1042)
==3687== by 0x81DA86: xml_init_syscalls_info(char const*) (xml-syscall.c:366)
==3687== by 0x81DBDD: init_syscalls_info(gdbarch*) (xml-syscall.c:398)
==3687== by 0x81E131: get_syscall_by_number(gdbarch*, int, syscall*) (xml-syscall.c:599)
==3687== by 0x5BE86F: catch_syscall_command_1(char*, int, cmd_list_element*) (break-catch-syscall.c:481)
==3687== by 0x4B46B1: do_sfunc(cmd_list_element*, char*, int) (cli-decode.c:138)
==3687== by 0x4B76B8: cmd_func(cmd_list_element*, char*, int) (cli-decode.c:1952)
==3687== by 0x7E91C7: execute_command(char*, int) (top.c:615)
==3687== by 0x6A422D: command_handler(char*) (event-top.c:583)
==3687== by 0x6A45F2: command_line_handler(char*) (event-top.c:773)
[...]
The problem is that if xrealloc decides it needs a new memory block,
it frees the previous block/pointer, and then text.reset() frees it
again.
gdb/ChangeLog:
2017-10-17 Pedro Alves <palves@redhat.com>
* xml-support.c (xml_fetch_content_from_file): Call
unique_ptr::release() instead unique_ptr::get() when passing
through xrealloc.
| -rw-r--r-- | gdb/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/xml-support.c | 2 |
2 files changed, 7 insertions, 1 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 6a8d16fef5d..65952c465b5 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2017-10-17 Pedro Alves <palves@redhat.com> + + * xml-support.c (xml_fetch_content_from_file): Call + unique_ptr::release() instead unique_ptr::get() when passing + through xrealloc. + 2017-10-17 Yao Qi <yao.qi@linaro.org> * regcache.c (regcache::xfer_part): Remove parameters read and diff --git a/gdb/xml-support.c b/gdb/xml-support.c index 76d03b90c70..42a4c918d6d 100644 --- a/gdb/xml-support.c +++ b/gdb/xml-support.c @@ -1039,7 +1039,7 @@ xml_fetch_content_from_file (const char *filename, void *baton) break; len = len * 2; - text.reset ((char *) xrealloc (text.get (), len)); + text.reset ((char *) xrealloc (text.release (), len)); } text.get ()[offset] = '\0'; |