From a93d9e03a31ec14405cb3a09aa95413b67067380 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 17 Aug 2021 19:35:48 -0700 Subject: Extend struct r_debug to support multiple namespaces [BZ #15971] Glibc does not provide an interface for debugger to access libraries loaded in multiple namespaces via dlmopen. The current rtld-debugger interface is described in the file: elf/rtld-debugger-interface.txt under the "Standard debugger interface" heading. This interface only provides access to the first link-map (LM_ID_BASE). 1. Bump r_version to 2 when multiple namespaces are used. This triggers the GDB bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28236 2. Add struct r_debug_extended to extend struct r_debug into a linked-list, where each element correlates to an unique namespace. 3. Initialize the r_debug_extended structure. Bump r_version to 2 for the new namespace and add the new namespace to the namespace linked list. 4. Add _dl_debug_update to return the address of struct r_debug' of a namespace. 5. Add a hidden symbol, _r_debug_extended, for struct r_debug_extended. 6. Provide the symbol, _r_debug, with size of struct r_debug, as an alias of _r_debug_extended, for programs which reference _r_debug. This fixes BZ #15971. Reviewed-by: Florian Weimer --- elf/dl-load.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'elf/dl-load.c') diff --git a/elf/dl-load.c b/elf/dl-load.c index 650e4edc35..39e0d074b4 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -949,7 +949,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, /* Initialize to keep the compiler happy. */ const char *errstring = NULL; int errval = 0; - struct r_debug *r = _dl_debug_initialize (0, nsid); + struct r_debug *r = _dl_debug_update (nsid); bool make_consistent = false; /* Get file information. To match the kernel behavior, do not fill -- cgit v1.2.3