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| author | H.J. Lu <hjl.tools@gmail.com> | 2020-12-28 05:28:49 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2021-01-13 14:02:11 -0800 |
| commit | af316e4627ea2069c0f690e926e04d92f802f054 (patch) | |
| tree | be4a33bcaed7e6a46fc9bc76627e4a6a3bfd1b09 /elf | |
| parent | 36eb01dd857f672c849b59d889e22a89e4ae5a75 (diff) | |
| download | glibc-af316e4627ea2069c0f690e926e04d92f802f054.tar.gz glibc-af316e4627ea2069c0f690e926e04d92f802f054.tar.xz glibc-af316e4627ea2069c0f690e926e04d92f802f054.zip | |
x86: Check IFUNC definition in unrelocated executable [BZ #20019]
Calling an IFUNC function defined in unrelocated executable also leads to segfault. Issue a fatal error message when calling IFUNC function defined in the unrelocated executable from a shared library. On x86, ifuncmain6pie failed with: [hjl@gnu-cfl-2 build-i686-linux]$ ./elf/ifuncmain6pie --direct ./elf/ifuncmain6pie: IFUNC symbol 'foo' referenced in '/export/build/gnu/tools-build/glibc-32bit/build-i686-linux/elf/ifuncmod6.so' is defined in the executable and creates an unsatisfiable circular dependency. [hjl@gnu-cfl-2 build-i686-linux]$ readelf -rW elf/ifuncmod6.so | grep foo 00003ff4 00000706 R_386_GLOB_DAT 0000400c foo_ptr 00003ff8 00000406 R_386_GLOB_DAT 00000000 foo 0000400c 00000401 R_386_32 00000000 foo [hjl@gnu-cfl-2 build-i686-linux]$ Remove non-JUMP_SLOT relocations against foo in ifuncmod6.so, which trigger the circular IFUNC dependency, and build ifuncmain6pie with -Wl,-z,lazy. (cherry picked from commits 6ea5b57afa5cdc9ce367d2b69a2cebfb273e4617 and 7137d682ebfcb6db5dfc5f39724718699922f06c)
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Makefile | 2 | ||||
| -rw-r--r-- | elf/ifuncmain6pie.c | 14 | ||||
| -rw-r--r-- | elf/ifuncmod6.c | 8 |
3 files changed, 9 insertions, 15 deletions
diff --git a/elf/Makefile b/elf/Makefile index 632a4d8b0f..e8384d1754 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -1348,6 +1348,8 @@ CFLAGS-ifuncmain7pie.c += $(pie-ccflag) CFLAGS-ifuncmain9pie.c += $(pie-ccflag) CFLAGS-tst-ifunc-textrel.c += $(pic-ccflag) +LDFLAGS-ifuncmain6pie = -Wl,-z,lazy + $(objpfx)ifuncmain1pie: $(objpfx)ifuncmod1.so $(objpfx)ifuncmain1staticpie: $(objpfx)ifuncdep1pic.o $(objpfx)ifuncmain1vispie: $(objpfx)ifuncmod1.so diff --git a/elf/ifuncmain6pie.c b/elf/ifuncmain6pie.c index 04faeb86ef..4a01906836 100644 --- a/elf/ifuncmain6pie.c +++ b/elf/ifuncmain6pie.c @@ -9,7 +9,6 @@ #include "ifunc-sel.h" typedef int (*foo_p) (void); -extern foo_p foo_ptr; static int one (void) @@ -28,20 +27,17 @@ foo_ifunc (void) } extern int foo (void); -extern foo_p get_foo (void); +extern int call_foo (void); extern foo_p get_foo_p (void); -foo_p my_foo_ptr = foo; +foo_p foo_ptr = foo; int main (void) { foo_p p; - p = get_foo (); - if (p != foo) - abort (); - if ((*p) () != -30) + if (call_foo () != -30) abort (); p = get_foo_p (); @@ -52,12 +48,8 @@ main (void) if (foo_ptr != foo) abort (); - if (my_foo_ptr != foo) - abort (); if ((*foo_ptr) () != -30) abort (); - if ((*my_foo_ptr) () != -30) - abort (); if (foo () != -30) abort (); diff --git a/elf/ifuncmod6.c b/elf/ifuncmod6.c index 2e16c1d06d..2f6d0715e6 100644 --- a/elf/ifuncmod6.c +++ b/elf/ifuncmod6.c @@ -4,7 +4,7 @@ extern int foo (void); typedef int (*foo_p) (void); -foo_p foo_ptr = foo; +extern foo_p foo_ptr; foo_p get_foo_p (void) @@ -12,8 +12,8 @@ get_foo_p (void) return foo_ptr; } -foo_p -get_foo (void) +int +call_foo (void) { - return foo; + return foo (); } |