The AT_RANDOM changes broke setuid / setgid executables
such as "ping". When the linker executes a setuid program,
it cleans the environment, removing any invalid environment
entries, and adding "NULL"s to the end of the environment
array for each removed variable. Later on, we try to determine
the location of the aux environment variable, and get tripped
up by these extra NULLs.
Reverting this patch will get setuid executables working again,
but getauxval() is still broken for setuid programs because of
this bug.
This reverts commit e3a49a8661.
Change-Id: I05c58a896b1fe32cfb5d95d43b096045cda0aa4a
Populate the stack canaries from the kernel supplied
AT_RANDOM value, which doesn't involve any system calls.
This is slightly faster (6 fewer syscalls) and avoids
unnecessarily reading /dev/urandom, which depletes entropy.
Bug: 7959813
Change-Id: If2b43100a2a9929666df3de56b6139fed969e0f1
Based on a pair of patches from Intel:
https://android-review.googlesource.com/#/c/43909/https://android-review.googlesource.com/#/c/44903/
For x86, this patch supports _both_ the global that ARM/MIPS use
and the per-thread TLS entry (%gs:20) that GCC uses by default. This
lets us support binaries built with any x86 toolchain (right now,
the NDK is emitting x86 code that uses the global).
I've also extended the original tests to cover ARM/MIPS too, and
be a little more thorough for x86.
Change-Id: I02f279a80c6b626aecad449771dec91df235ad01
