From 2a764c6ee848dfe92cb2921ed3b14085f15d9e79 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Thu, 31 Oct 2019 13:23:06 +0100 Subject: [PATCH] Enhance _dl_catch_exception to allow disabling exception handling In some cases, it is necessary to introduce noexcept regions where raised dynamic loader exceptions (e.g., from lazy binding) are fatal, despite being nested in a code region with an active exception handler. This change enhances _dl_catch_exception with to provide such a capability. The existing function is reused, so that it is not necessary to introduce yet another function with a similar purpose. Change-Id: Iec1bf642ff95a349fdde8040e9baf851ac7b8904 --- elf/dl-error-skeleton.c | 12 ++++++++++++ sysdeps/generic/ldsodefs.h | 4 +++- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/elf/dl-error-skeleton.c b/elf/dl-error-skeleton.c index a261af68b6..7caf28f0fd 100644 --- a/elf/dl-error-skeleton.c +++ b/elf/dl-error-skeleton.c @@ -173,6 +173,18 @@ int _dl_catch_exception (struct dl_exception *exception, void (*operate) (void *), void *args) { + /* If exception is NULL, temporarily disable exception handling. + Exceptions during operate (args) are fatal. */ + if (exception == NULL) + { + struct catch *const old = catch_hook; + catch_hook = NULL; + operate (args); + /* If we get here, the operation was successful. */ + catch_hook = old; + return 0; + } + /* We need not handle `receiver' since setting a `catch' is handled before it. */ diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 4d67c05e72..891049dd1a 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -861,7 +861,9 @@ libc_hidden_proto (_dl_catch_error) /* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero. Otherwise, store a copy of the raised exception in *EXCEPTION, - which has to be freed by _dl_exception_free. */ + which has to be freed by _dl_exception_free. As a special case, if + EXCEPTION is null, call OPERATE (ARGS) with exception handling + disabled (so that exceptions are fatal). */ int _dl_catch_exception (struct dl_exception *exception, void (*operate) (void *), void *args); libc_hidden_proto (_dl_catch_exception)