commit a03631124602f2dcef40d46660b96d2e51c44bfd
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Fri Apr 5 10:27:29 2024 -0300

    stdlib: fix arc4random fallback to /dev/urandom (BZ 31612)
    
    The __getrandom_nocancel used by __arc4random_buf uses
    INLINE_SYSCALL_CALL (which returns -1/errno) and the loop checks for
    the return value instead of errno to fallback to /dev/urandom.
    
    The malloc code now uses __getrandom_nocancel_nostatus, which uses
    INTERNAL_SYSCALL_CALL, so there is no need to use the variant that does
    not set errno (BZ#29624).
    
    Checked on x86_64-linux-gnu.
    
    Reviewed-by: Xi Ruoyao <xry111@xry111.site>
    (cherry picked from commit 184b9e530e6326e668709826903b6d30dc6cac3f)

diff --git a/stdlib/arc4random.c b/stdlib/arc4random.c
index 3ae8fc130234b04d..7818cb9cf66e0f3b 100644
--- a/stdlib/arc4random.c
+++ b/stdlib/arc4random.c
@@ -51,7 +51,7 @@ __arc4random_buf (void *p, size_t n)
 	  n -= l;
 	  continue; /* Interrupted by a signal; keep going.  */
 	}
-      else if (l == -ENOSYS)
+      else if (l < 0 && errno == ENOSYS)
 	break; /* No syscall, so fallback to /dev/urandom.  */
       arc4random_getrandom_failure ();
     }