malloc: Use __getrandom_nocancel during tcache initiailization

Cancellation currently cannot happen at this point because dlopen
as used by the unwind link always performs additional allocations
for libgcc_s.so.1, even if it has been loaded already as a dependency
of the main executable.  But it seems prudent not to rely on this
quirk.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
This commit is contained in:
Florian Weimer 2022-08-01 15:49:07 +02:00
parent 032712621f
commit 7187efd0aa

View File

@ -254,6 +254,7 @@
/* For tcache double-free check. */
#include <random-bits.h>
#include <sys/random.h>
#include <not-cancel.h>
/*
Debugging:
@ -3153,7 +3154,7 @@ static uintptr_t tcache_key;
static void
tcache_key_initialize (void)
{
if (__getrandom (&tcache_key, sizeof(tcache_key), GRND_NONBLOCK)
if (__getrandom_nocancel (&tcache_key, sizeof(tcache_key), GRND_NONBLOCK)
!= sizeof (tcache_key))
{
tcache_key = random_bits ();