aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJonathan Wakely <jwakely@redhat.com>2020-11-19 13:33:11 +0000
committerJonathan Wakely <jwakely@redhat.com>2020-11-19 13:33:11 +0000
commitb108faa9400e13a3d00dd7f71cff0ac45e29c5c9 (patch)
tree46b5434fd6d1c44308337d97d5cb23e66124f416
parentbf425849f1dfa11f509e9ec251056d1e769b1ac2 (diff)
downloadgcc-b108faa9400e13a3d00dd7f71cff0ac45e29c5c9.zip
gcc-b108faa9400e13a3d00dd7f71cff0ac45e29c5c9.tar.gz
gcc-b108faa9400e13a3d00dd7f71cff0ac45e29c5c9.tar.bz2
libstdc++: Fix overflow checks to use the correct "time_t" [PR 93456]
I recently added overflow checks to src/c++11/futex.cc for PR 93456, but then changed the type of the timespec for PR 93421. This meant the overflow checks were no longer using the right range, because the variable being written to might be smaller than time_t. This introduces new typedef that corresponds to the tv_sec member of the struct being passed to the syscall, and uses that typedef in the range checks. libstdc++-v3/ChangeLog: PR libstdc++/93421 PR libstdc++/93456 * src/c++11/futex.cc (syscall_time_t): New typedef for the type of the syscall_timespec::tv_sec member. (relative_timespec, _M_futex_wait_until) (_M_futex_wait_until_steady): Use syscall_time_t in overflow checks, not time_t.
-rw-r--r--libstdc++-v3/src/c++11/futex.cc14
1 files changed, 8 insertions, 6 deletions
diff --git a/libstdc++-v3/src/c++11/futex.cc b/libstdc++-v3/src/c++11/futex.cc
index 33e2097..290201a 100644
--- a/libstdc++-v3/src/c++11/futex.cc
+++ b/libstdc++-v3/src/c++11/futex.cc
@@ -64,8 +64,10 @@ namespace
// The SYS_futex syscall still uses the old definition of timespec
// where tv_sec is 32 bits, so define a type that matches that.
struct syscall_timespec { long tv_sec; long tv_nsec; };
+ using syscall_time_t = long;
#else
using syscall_timespec = ::timespec;
+ using syscall_time_t = time_t;
#endif
// Return the relative duration from (now_s + now_ns) to (abs_s + abs_ns)
@@ -86,9 +88,9 @@ namespace
const auto rel_s = abs_s.count() - now_s;
// Convert the absolute timeout to a relative timeout, without overflow.
- if (rel_s > __int_traits<time_t>::__max) [[unlikely]]
+ if (rel_s > __int_traits<syscall_time_t>::__max) [[unlikely]]
{
- rt.tv_sec = __int_traits<time_t>::__max;
+ rt.tv_sec = __int_traits<syscall_time_t>::__max;
rt.tv_nsec = 999999999;
}
else
@@ -130,8 +132,8 @@ namespace
return false;
syscall_timespec rt;
- if (__s.count() > __int_traits<time_t>::__max) [[unlikely]]
- rt.tv_sec = __int_traits<time_t>::__max;
+ if (__s.count() > __int_traits<syscall_time_t>::__max) [[unlikely]]
+ rt.tv_sec = __int_traits<syscall_time_t>::__max;
else
rt.tv_sec = __s.count();
rt.tv_nsec = __ns.count();
@@ -206,8 +208,8 @@ namespace
return false;
syscall_timespec rt;
- if (__s.count() > __int_traits<time_t>::__max) [[unlikely]]
- rt.tv_sec = __int_traits<time_t>::__max;
+ if (__s.count() > __int_traits<syscall_time_t>::__max) [[unlikely]]
+ rt.tv_sec = __int_traits<syscall_time_t>::__max;
else
rt.tv_sec = __s.count();
rt.tv_nsec = __ns.count();