Briefly provide an explanation for go back-oriented programming: what sort of software vulnerability and countermeasure does this
Question:
Briefly provide an explanation for go back-oriented programming: what sort of software vulnerability and countermeasure does this class of attacks goal, how does it work, and under what conditions is it applicable? [6 marks] (b) Identify and connect a capacity vulnerability inside the following C characteristic: [2 marks] #include void *bitmalloc(size_t bits) return malloc((bits + 7)/eight);
(c) On a Linux file server, you locate this document: $ ls -l -rw----r-- 1 frank college students 13593 May 31 14:fifty five query.Tex User frank is a member of institution college students. (i) Based at the POSIX get admission to-manage settings proven, illustrate how the server's running system will authorize get admission to (if-assertion pseudo code). [3 marks] (ii) What does an equal Windows NTFS get admission to-manage list seem like? [3 marks] (iii) Does the Windows GUI for manipulating NTFS get entry to-control lists permit users to enter this configuration? [2 marks] (d) Give an instance of how POSIX record-system get entry to manage can be used to offer the equal of password safety for parts of the document area. In precise, show how user alice can set up a listing papers such that only the ones individuals of organization committee (which includes alice) who understand the name of the game string "SEL-4sB3" can examine a record confined.Pdf. Show the setup both as a sequence of shell instructions that alice can use to create it, or inside the form of the metadata of the files and directories worried (as ls -l could output it).
(a) (i) Describe the 4 training in Flynn's taxonomy of computing structures. [4 marks] (ii) Describe Amdahl's law and use it to calculate the most speedup conceivable by using walking a program, P, on a multicore system, S, wherein eighty% of P is parallel and S includes 16 cores. [4 marks] (b) Consider the subsequent pseudo-code this is run on a SIMD processor with eight lanes, in which i gives the lane variety. R1 = load X[i] r2 = load Y[i] if (i%2 == 0) if (i%8 == zero) r1 = r1 * 2 r1 = r1 + r2 endif else r1 = r1 - r2 endif save r1, X[i] (i) Describe how the processor can help branch divergence among the exclusive lanes. [4 marks] (ii) With the aid of a diagram, display the utilisation of the SIMD lanes for each pseudo-code operation, therefore calculate the code's performance (average utilisation of the SIMD lanes). [6 marks] (iii) What architectural technique do GPUs employ to allow them to carry out beneficial work despite the fact that the loads from X and Y often motive stalls? [
Accounting
ISBN: 978-0324662962
23rd Edition
Authors: Jonathan E. Duchac, James M. Reeve, Carl S. Warren