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* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-061-1/+1
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* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
* stdlib: Fix data race in __run_exit_handlers [BZ #27749]Vitaly Buka2021-05-141-0/+110
Keep __exit_funcs_lock almost all the time and unlock it only to execute callbacks. This fixed two issues. 1. f->func.cxa was modified outside the lock with rare data race like: thread 0: __run_exit_handlers unlock __exit_funcs_lock thread 1: __internal_atexit locks __exit_funcs_lock thread 0: f->flavor = ef_free; thread 1: sees ef_free and use it as new thread 1: new->func.cxa.fn = (void (*) (void *, int)) func; thread 1: new->func.cxa.arg = arg; thread 1: new->flavor = ef_cxa; thread 0: cxafct = f->func.cxa.fn; // it's wrong fn! thread 0: cxafct (f->func.cxa.arg, status); // it's wrong arg! thread 0: goto restart; thread 0: call the same exit_function again as it's ef_cxa 2. Don't unlock in main while loop after *listp = cur->next. If *listp is NULL and __exit_funcs_done is false another thread may fail in __new_exitfn on assert (l != NULL): thread 0: *listp = cur->next; // It can be the last: *listp = NULL. thread 0: __libc_lock_unlock thread 1: __libc_lock_lock in __on_exit thread 1: __new_exitfn thread 1: if (__exit_funcs_done) // false: thread 0 isn't there yet. thread 1: l = *listp thread 1: moves one and crashes on assert (l != NULL); The test needs multiple iterations to consistently fail without the fix. Fixes https://sourceware.org/bugzilla/show_bug.cgi?id=27749 Checked on x86_64-linux-gnu. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>