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| author | Florian Weimer <fweimer@redhat.com> | 2018-06-26 10:24:52 +0200 |
|---|---|---|
| committer | Florian Weimer <fweimer@redhat.com> | 2018-06-26 10:24:52 +0200 |
| commit | c402355dfa7807b8e0adb27c009135a7e2b9f1b0 (patch) | |
| tree | 24a50fd3ad75c969ed22e0c456f33ee75a6bd922 | |
| parent | 43b1048ab9418e902aac8c834a7a9a88c501620a (diff) | |
| download | glibc-c402355dfa7807b8e0adb27c009135a7e2b9f1b0.tar.gz glibc-c402355dfa7807b8e0adb27c009135a7e2b9f1b0.tar.xz glibc-c402355dfa7807b8e0adb27c009135a7e2b9f1b0.zip | |
libio: Disable vtable validation in case of interposition [BZ #23313]
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | libio/vtables.c | 16 |
2 files changed, 21 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index f8d28b496e..664928d5fe 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2018-06-26 Florian Weimer <fweimer@redhat.com> + + [BZ #23313] + * libio/vtables.c (check_stdfiles_vtables): New ELF constructor. + 2018-06-25 Florian Weimer <fweimer@redhat.com> [BZ #18023] diff --git a/libio/vtables.c b/libio/vtables.c index 9fd4ccf642..9df75668c8 100644 --- a/libio/vtables.c +++ b/libio/vtables.c @@ -71,3 +71,19 @@ _IO_vtable_check (void) __libc_fatal ("Fatal error: glibc detected an invalid stdio handle\n"); } + +/* Some variants of libstdc++ interpose _IO_2_1_stdin_ etc. and + install their own vtables directly, without calling _IO_init or + other functions. Detect this by looking at the vtables values + during startup, and disable vtable validation in this case. */ +#ifdef SHARED +__attribute__ ((constructor)) +static void +check_stdfiles_vtables (void) +{ + if (_IO_2_1_stdin_.vtable != &_IO_file_jumps + || _IO_2_1_stdout_.vtable != &_IO_file_jumps + || _IO_2_1_stderr_.vtable != &_IO_file_jumps) + IO_set_accept_foreign_vtables (&_IO_vtable_check); +} +#endif |