Merge remote-tracking branch 'upstream-public/pr/2151' into mbedtls-2.1
diff --git a/ChangeLog b/ChangeLog
index f496a13..505aa63 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,9 @@
* Fix for Clang, which was reporting a warning for the bignum.c inline
assembly for AMD64 targets creating string literals greater than those
permitted by the ISO C99 standard. Found by Aaron Jones. Fixes #482.
+ * Fix runtime error in `mbedtls_platform_entropy_poll()` when run
+ through qemu user emulation. Reported and fix suggested by randombit
+ in #1212. Fixes #1212.
= mbed TLS 2.1.17 branch released 2018-11-30
diff --git a/library/entropy_poll.c b/library/entropy_poll.c
index 096c023..e73c719 100644
--- a/library/entropy_poll.c
+++ b/library/entropy_poll.c
@@ -81,6 +81,7 @@
#include <sys/syscall.h>
#if defined(SYS_getrandom)
#define HAVE_GETRANDOM
+#include <errno.h>
static int getrandom_wrapper( void *buf, size_t buflen, unsigned int flags )
{
@@ -90,47 +91,8 @@
memset( buf, 0, buflen );
#endif
#endif
-
return( syscall( SYS_getrandom, buf, buflen, flags ) );
}
-
-#include <sys/utsname.h>
-/* Check if version is at least 3.17.0 */
-static int check_version_3_17_plus( void )
-{
- int minor;
- struct utsname un;
- const char *ver;
-
- /* Get version information */
- uname(&un);
- ver = un.release;
-
- /* Check major version; assume a single digit */
- if( ver[0] < '3' || ver[0] > '9' || ver [1] != '.' )
- return( -1 );
-
- if( ver[0] - '0' > 3 )
- return( 0 );
-
- /* Ok, so now we know major == 3, check minor.
- * Assume 1 or 2 digits. */
- if( ver[2] < '0' || ver[2] > '9' )
- return( -1 );
-
- minor = ver[2] - '0';
-
- if( ver[3] >= '0' && ver[3] <= '9' )
- minor = 10 * minor + ver[3] - '0';
- else if( ver [3] != '.' )
- return( -1 );
-
- if( minor < 17 )
- return( -1 );
-
- return( 0 );
-}
-static int has_getrandom = -1;
#endif /* SYS_getrandom */
#endif /* __linux__ */
@@ -141,22 +103,21 @@
{
FILE *file;
size_t read_len;
+ int ret;
((void) data);
#if defined(HAVE_GETRANDOM)
- if( has_getrandom == -1 )
- has_getrandom = ( check_version_3_17_plus() == 0 );
-
- if( has_getrandom )
+ ret = getrandom_wrapper( output, len, 0 );
+ if( ret >= 0 )
{
- int ret;
-
- if( ( ret = getrandom_wrapper( output, len, 0 ) ) < 0 )
- return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
-
*olen = ret;
return( 0 );
}
+ else if( errno != ENOSYS )
+ return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+ /* Fall through if the system call isn't known. */
+#else
+ ((void) ret);
#endif /* HAVE_GETRANDOM */
*olen = 0;