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de6591238b
When dynamically linking, ifunc resolvers are called before TLS is
initialized, so they cannot be safely stack-protected.
We avoid disabling stack-protection on large numbers of files by
using __attribute__ ((__optimize__ ("-fno-stack-protector")))
to turn it off just for the resolvers themselves. (We provide
the attribute even when statically linking, because we will later
use it elsewhere too.)
65 lines
1.1 KiB
C
65 lines
1.1 KiB
C
/* Test STT_GNU_IFUNC symbols without direct function call. */
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#include "ifunc-sel.h"
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int global = -1;
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/* Can't use __attribute__((visibility("protected"))) until the GCC bug:
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65248
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is fixed. */
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asm (".protected global");
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static int
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one (void)
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{
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return 1;
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}
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static int
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minus_one (void)
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{
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return -1;
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}
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static int
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zero (void)
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{
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return 0;
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}
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void * foo_ifunc (void) __asm__ ("foo");
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__asm__(".type foo, %gnu_indirect_function");
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void *
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inhibit_stack_protector
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foo_ifunc (void)
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{
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return ifunc_sel (one, minus_one, zero);
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}
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void * foo_hidden_ifunc (void) __asm__ ("foo_hidden");
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__asm__(".type foo_hidden, %gnu_indirect_function");
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void *
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inhibit_stack_protector
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foo_hidden_ifunc (void)
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{
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return ifunc_sel (minus_one, one, zero);
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}
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void * foo_protected_ifunc (void) __asm__ ("foo_protected");
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__asm__(".type foo_protected, %gnu_indirect_function");
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void *
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inhibit_stack_protector
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foo_protected_ifunc (void)
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{
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return ifunc_sel (one, zero, minus_one);
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}
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/* Test hidden indirect function. */
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__asm__(".hidden foo_hidden");
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/* Test protected indirect function. */
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__asm__(".protected foo_protected");
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