Unverified Commit 0032ce0f authored by Peilin Ye's avatar Peilin Ye Committed by Christian Brauner
Browse files

ptrace: Prevent kernel-infoleak in ptrace_get_syscall_info() 



ptrace_get_syscall_info() is potentially copying uninitialized stack
memory to userspace, since the compiler may leave a 3-byte hole near the
beginning of `info`. Fix it by adding a padding field to `struct
ptrace_syscall_info`.

Fixes: 201766a2 ("ptrace: add PTRACE_GET_SYSCALL_INFO request")
Suggested-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarPeilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: default avatarDmitry V. Levin <ldv@altlinux.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200801152044.230416-1-yepeilin.cs@gmail.com


Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
parent 9123e3a7

include/uapi/linux/ptrace.h

+2 −1
Original line number Diff line number Diff line
@@ -81,7 +81,8 @@ struct seccomp_metadata { 


struct ptrace_syscall_info {

	__u8 op;	/* PTRACE_SYSCALL_INFO_* */

	__u32 arch __attribute__((__aligned__(sizeof(__u32))));

	__u8 pad[3];

	__u32 arch;

	__u64 instruction_pointer;

	__u64 stack_pointer;

	union {