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a687683b99
Rtld locks from libthr defer signals delivery, which means that binding is not possible while a signal handler is executed. Binding might upgrade read-locked rtld_bind_lock to write-lock, if symbol resolution requires loading filters. If a signal would be delivered while rtld is in read-locked section, and signal handler needs binding which upgrades the lock, for non-threaded image that uses default rtld locks, we get the rtld data structures modified under the top-level active rtld frame. To correct the problem, mask signals for read-locking of default locks in addition to the write-locking. It is very cheap now with sigfastblock(2). Note that the global state is used to track pre-locked state of either sigfastblock(2) or signal mask (if sigfastblock(2) is administratively disabled). It is fine for non-threaded images since there are no other threads. But I believe that it is fine for threaded images using libc_r as well, since masking signals disables preemption (I did not tested it). NetBSD PR: https://gnats.netbsd.org/56979 Reported by: tmunro Reviewed by: markj Sponsored by: The FreeBSD Foundation MFC after: 2 weeks Differential revision: https://reviews.freebsd.org/D36396 |
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| atf | ||
| atrun | ||
| blacklistd-helper | ||
| bootpd | ||
| comsat | ||
| dma | ||
| fingerd | ||
| flua | ||
| ftpd | ||
| getty | ||
| hyperv | ||
| mail.local | ||
| makewhatis.local | ||
| mknetid | ||
| phttpget | ||
| pppoed | ||
| rbootd | ||
| rc | ||
| revnetgroup | ||
| rpc.rquotad | ||
| rpc.rstatd | ||
| rpc.rusersd | ||
| rpc.rwalld | ||
| rpc.sprayd | ||
| rtld-elf | ||
| rtld-elf32 | ||
| save-entropy | ||
| smrsh | ||
| talkd | ||
| tcpd | ||
| telnetd | ||
| tests | ||
| tftp-proxy | ||
| tftpd | ||
| ulog-helper | ||
| ypxfr | ||
| Makefile | ||
| Makefile.amd64 | ||
| Makefile.i386 | ||
| Makefile.inc | ||