From 8949da7ab1c0dbf801e8bc78f0c0adc625020f75 Mon Sep 17 00:00:00 2001 From: Alexey Izbyshev Date: Thu, 2 Mar 2023 08:10:47 +0300 Subject: select: fix 64-bit timeout truncation on pre-time64 kernels If the (normalized) timeout passed to select exceeds INT_MAX seconds on an arch with SYS_pselect6_time64 and the kernel is too old to support time64 syscalls, the timeout is implicitly converted to (32-bit) long on the fallback path, losing its upper 32 bits and potentially becoming a small positive value, violating the intended semantics, or even a negative value, causing the fallback syscall failure. Fix this by saturating the timeout at INT_MAX as done in other time64 fallback cases. --- src/select/select.c | 1 + 1 file changed, 1 insertion(+) diff --git a/src/select/select.c b/src/select/select.c index 8a786884..f1d72863 100644 --- a/src/select/select.c +++ b/src/select/select.c @@ -33,6 +33,7 @@ int select(int n, fd_set *restrict rfds, fd_set *restrict wfds, fd_set *restrict ((syscall_arg_t[]){ 0, _NSIG/8 })); if (SYS_pselect6 == SYS_pselect6_time64 || r!=-ENOSYS) return __syscall_ret(r); + s = CLAMP(s); #endif #ifdef SYS_select return syscall_cp(SYS_select, n, rfds, wfds, efds, -- cgit v1.2.1