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Eric W. Biederman aa3fbddbb8 ptrace: Don't allow accessing an undumpable mm ... commit 84d77d3f06 upstream. It is the reasonable expectation that if an executable file is not readable there will be no way for a user without special privileges to read the file. This is enforced in ptrace_attach but if ptrace is already attached before exec there is no enforcement for read-only executables. As the only way to read such an mm is through access_process_vm spin a variant called ptrace_access_vm that will fail if the target process is not being ptraced by the current process, or the current process did not have sufficient privileges when ptracing began to read the target processes mm. In the ptrace implementations replace access_process_vm by ptrace_access_vm. There remain several ptrace sites that still use access_process_vm as they are reading the target executables instructions (for kernel consumption) or register stacks. As such it does not appear necessary to add a permission check to those calls. This bug has always existed in Linux. Fixes: v1.0 Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> [bwh: Backported to 3.16: - Pass around only a write flag, not gup_flags - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>		History 2018-01-01 20:52:11 +00:00
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arch-v10	cris: update comments for generic idle conversion	2014-06-06 16:08:18 -07:00
arch-v32	ptrace: Don't allow accessing an undumpable mm	2018-01-01 20:52:11 +00:00
boot	cris: Only build flash rescue image if CONFIG_ETRAX_AXISFLASHMAP is selected	2017-03-16 02:26:18 +00:00
configs	kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT	2011-01-20 17:02:05 -08:00
include	cris: buggered copy_from_user/copy_to_user/clear_user	2016-11-20 01:17:27 +00:00
kernel	cris: cpuinfo_op should depend on CONFIG_PROC_FS	2014-04-07 16:36:09 -07:00
mm	vm: add VM_FAULT_SIGSEGV handling support	2015-02-04 10:58:27 +00:00
Kconfig	Kconfig: rename HAS_IOPORT to HAS_IOPORT_MAP	2014-04-07 16:36:11 -07:00
Kconfig.debug	Kconfig: remove a few puzzling comments	2011-10-31 10:58:48 +01:00
Makefile	UAPI: Partition the header include path sets and add uapi/ header directories	2012-10-02 18:01:26 +01:00