mbox

[0/4] aarch64: avoid mprotect(PROT_BTI|PROT_EXEC) [BZ #26831]

Message ID cover.1604393169.git.szabolcs.nagy@arm.com
Headers

Message

Szabolcs Nagy Nov. 3, 2020, 10:25 a.m. UTC 
  Re-mmap executable segments instead of mprotecting them in
case mprotect is seccomp filtered.

For the kernel mapped main executable we don't have the fd
for re-mmap so linux needs to be updated to add BTI. (In the
presence of seccomp filters for mprotect(PROT_EXEC) the libc
cannot change BTI protection at runtime based on user space
policy so it is better if the kernel maps BTI compatible
binaries with PROT_BTI by default.)

Szabolcs Nagy (4):
  elf: Pass the fd to note processing [BZ #26831]
  elf: Move note processing after l_phdr is updated [BZ #26831]
  aarch64: Use mmap to add PROT_BTI instead of mprotect [BZ #26831]
  aarch64: Remove the bti link_map field [BZ #26831]

 elf/dl-load.c              | 38 ++++++++++++++++---------------
 elf/rtld.c                 |  4 ++--
 sysdeps/aarch64/dl-bti.c   | 46 ++++++++++++++++++++------------------
 sysdeps/aarch64/dl-prop.h  | 17 +++++++-------
 sysdeps/aarch64/linkmap.h  |  1 -
 sysdeps/generic/dl-prop.h  |  6 ++---
 sysdeps/generic/ldsodefs.h |  5 +++--
 sysdeps/x86/dl-prop.h      |  6 ++---
 8 files changed, 64 insertions(+), 59 deletions(-)