236670 2022-02-15 14:41:04 -0800 OSAllocatorPosix::tryReserveUncommittedAligned() should not use PROT_NONE on non-linux platforms 2022-02-22 14:42:18 -0800 1 1 1 Unclassified WebKit Platform WebKit Nightly Build Unspecified Unspecified NEW https://bugs.webkit.org/show_bug.cgi?id=236625 InRadar P2 Normal --- 1 yoshiaki.jitsukawa basuke webkit-bug-importer oldest_to_newest 1841950 0 yoshiaki.jitsukawa 2022-02-15 14:41:04 -0800 OSAllocatorPosix::tryReserveUncommittedAligned() should not use PROT_NONE on non-linux platforms. Only on linux PROT_NONE is used for deccommitted pages. That is, protection flags are set on commit() only on Linux. https://github.com/WebKit/WebKit/blob/9067a50/Source/WTF/wtf/posix/OSAllocatorPOSIX.cpp#L228 However in tryReserveUncommittedAligned() PROT_NONE is used for platforms other than #if PLATFORM(MAC) || USE(APPLE_INTERNAL_SDK), which may result in protection faults because appropriate flags won't be set on commit(). 1842935 1 basuke 2022-02-17 09:25:53 -0800 (In reply to Yoshiaki Jitsukawa from comment #0) > OSAllocatorPosix::tryReserveUncommittedAligned() should not use PROT_NONE on > non-linux platforms. > > Only on linux PROT_NONE is used for deccommitted pages. That is, protection > flags are set on commit() only on Linux. > https://github.com/WebKit/WebKit/blob/9067a50/Source/WTF/wtf/posix/ > OSAllocatorPOSIX.cpp#L228 > > However in tryReserveUncommittedAligned() PROT_NONE is used for platforms > other than > #if PLATFORM(MAC) || USE(APPLE_INTERNAL_SDK), > which may result in protection faults because appropriate flags won't be set > on commit(). Linux implementation is so much depends on Linux memory management way and very different from other port. 1844876 2 webkit-bug-importer 2022-02-22 14:42:18 -0800 <rdar://problem/89317522>