Date: Sun, 24 Jan 2021 21:48:11 +0300 (MSK) From: Alexander Monakov <amonakov@...ras.ru> To: musl@...ts.openwall.com cc: Andrew Rogers <andrew.rogerstech@...il.com> Subject: Re: Potential DL_NOMMU_SUPPORT bug. > > sdcard [pseudo-]partition is usually mounted noexec, so mmap with PROT_EXEC > > should fail. > > Uhg, that makes no sense. Does it enforce that even for MAP_PRIVATE, > which should semantically be equivalent to just making anon memory > with the requested permissions and copying the file contents into it?? I think it makes sense: isn't the entire point of 'noexec' that a user who has write access only to noexec filesystems will not be able to run arbitrary binary code (assuming the already-present binaries are not cooperative, unlike musl ld.so with the above patch would be)? Enforcing noexec for MAP_PRIVATE ensures the users can not trivially side-step noexec by invoking ld.so (without extra checks on ld.so side). Alexander
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.