diff options
Diffstat (limited to 'backport-elf-Do-not-completely-clear-reused-namespace-in-dlmo.patch')
| -rw-r--r-- | backport-elf-Do-not-completely-clear-reused-namespace-in-dlmo.patch | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/backport-elf-Do-not-completely-clear-reused-namespace-in-dlmo.patch b/backport-elf-Do-not-completely-clear-reused-namespace-in-dlmo.patch new file mode 100644 index 0000000..ac2e783 --- /dev/null +++ b/backport-elf-Do-not-completely-clear-reused-namespace-in-dlmo.patch @@ -0,0 +1,98 @@ +From 2c42257314536b94cc8d52edede86e94e98c1436 Mon Sep 17 00:00:00 2001 +From: Florian Weimer <fweimer@redhat.com> +Date: Fri, 14 Oct 2022 11:02:25 +0200 +Subject: [PATCH] elf: Do not completely clear reused namespace in +dlmopen (bug + 29600) + +The data in the _ns_debug member must be preserved, otherwise +_dl_debug_initialize enters an infinite loop. To be conservative, +only clear the libc_map member for now, to fix bug 29528. + +Fixes commit d0e357ff45a75553dee3b17ed7d303bfa544f6fe +("elf: Call __libc_early_init for reused namespaces (bug 29528)"), +by reverting most of it. + +Reviewed-by: Carlos O'Donell <carlos@redhat.com> +Tested-by: Carlos O'Donell <carlos@redhat.com> +--- + elf/dl-open.c | 14 ++++++-------- + elf/tst-dlmopen-twice.c | 28 ++++++++++++++++++++++++---- + 2 files changed, 30 insertions(+), 12 deletions(-) + +diff --git a/elf/dl-open.c b/elf/dl-open.c +index 9d7b764b..0820c34b 100644 +--- a/elf/dl-open.c ++++ b/elf/dl-open.c +@@ -857,15 +857,13 @@ _dl_open (const char *file, int mode, const void *caller_dlopen, Lmid_t nsid, + _dl_signal_error (EINVAL, file, NULL, N_("\ + no more namespaces available for dlmopen()")); + } ++ else if (nsid == GL(dl_nns)) ++ { ++ __rtld_lock_initialize (GL(dl_ns)[nsid]._ns_unique_sym_table.lock); ++ ++GL(dl_nns); ++ } + +- if (nsid == GL(dl_nns)) +- ++GL(dl_nns); +- +- /* Initialize the new namespace. Most members are +- zero-initialized, only the lock needs special treatment. */ +- memset (&GL(dl_ns)[nsid], 0, sizeof (GL(dl_ns)[nsid])); +- __rtld_lock_initialize (GL(dl_ns)[nsid]._ns_unique_sym_table.lock); +- ++ GL(dl_ns)[nsid].libc_map = NULL; + _dl_debug_initialize (0, nsid)->r_state = RT_CONSISTENT; + } + /* Never allow loading a DSO in a namespace which is empty. Such +diff --git a/elf/tst-dlmopen-twice.c b/elf/tst-dlmopen-twice.c +index 449f3c8f..70c71fe1 100644 +--- a/elf/tst-dlmopen-twice.c ++++ b/elf/tst-dlmopen-twice.c +@@ -16,18 +16,38 @@ + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +-#include <support/xdlfcn.h> ++#include <stdio.h> + #include <support/check.h> ++#include <support/xdlfcn.h> + +-static int +-do_test (void) ++/* Run the test multiple times, to check finding a new namespace while ++ another namespace is already in use. This used to trigger bug 29600. */ ++static void ++recurse (int depth) + { +- void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod1.so", RTLD_NOW); ++ if (depth == 0) ++ return; ++ ++ printf ("info: running at depth %d\n", depth); ++ void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod1.so", ++ RTLD_NOW); + xdlclose (handle); + handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod2.so", RTLD_NOW); + int (*run_check) (void) = xdlsym (handle, "run_check"); + TEST_COMPARE (run_check (), 0); ++ recurse (depth - 1); + xdlclose (handle); ++} ++ ++static int ++do_test (void) ++{ ++ /* First run the test without nesting. */ ++ recurse (1); ++ ++ /* Then with nesting. The constant needs to be less than the ++ internal DL_NNS namespace constant. */ ++ recurse (10); + return 0; + } + +-- +2.33.0 + |