kvmvapic: Prevent reading beyond the end of guest RAM

rom_state_paddr is guest provided (caller address of outw(VAPIC_PORT) +
writen 16-bit value) and can be influenced to point beyond the end of
the host memory backing the guest's RAM. Make sure we do not use this
pointer to actually read beyond the limits.

Reading arbitrary guest bytes is harmless, the guest kernel has to
manage access to this I/O port anyway.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
1 file changed
tree: 368e14461ebaedec159665866011bfb3e779b02c
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. default-configs/
  6. disas/
  7. docs/
  8. fpu/
  9. fsdev/
  10. gdb-xml/
  11. hw/
  12. include/
  13. libcacard/
  14. linux-headers/
  15. linux-user/
  16. net/
  17. pc-bios/
  18. po/
  19. qapi/
  20. qga/
  21. qobject/
  22. qom/
  23. roms/
  24. scripts/
  25. slirp/
  26. stubs/
  27. sysconfigs/
  28. target-alpha/
  29. target-arm/
  30. target-cris/
  31. target-i386/
  32. target-lm32/
  33. target-m68k/
  34. target-microblaze/
  35. target-mips/
  36. target-moxie/
  37. target-openrisc/
  38. target-ppc/
  39. target-s390x/
  40. target-sh4/
  41. target-sparc/
  42. target-unicore32/
  43. target-xtensa/
  44. tcg/
  45. tests/
  46. trace/
  47. ui/
  48. util/
  49. .exrc
  50. .gitignore
  51. .gitmodules
  52. .mailmap
  53. aio-posix.c
  54. aio-win32.c
  55. arch_init.c
  56. async.c
  57. balloon.c
  58. block-migration.c
  59. block.c
  60. blockdev-nbd.c
  61. blockdev.c
  62. blockjob.c
  63. bt-host.c
  64. bt-vhci.c
  65. Changelog
  66. CODING_STYLE
  67. configure
  68. COPYING
  69. COPYING.LIB
  70. coroutine-gthread.c
  71. coroutine-sigaltstack.c
  72. coroutine-ucontext.c
  73. coroutine-win32.c
  74. cpu-exec.c
  75. cpus.c
  76. cputlb.c
  77. device-hotplug.c
  78. device_tree.c
  79. disas.c
  80. dma-helpers.c
  81. dump.c
  82. exec.c
  83. gdbstub.c
  84. HACKING
  85. hmp-commands.hx
  86. hmp.c
  87. hmp.h
  88. iohandler.c
  89. ioport.c
  90. kvm-all.c
  91. kvm-stub.c
  92. LICENSE
  93. main-loop.c
  94. MAINTAINERS
  95. Makefile
  96. Makefile.objs
  97. Makefile.target
  98. memory.c
  99. memory_mapping.c
  100. migration-exec.c
  101. migration-fd.c
  102. migration-rdma.c
  103. migration-tcp.c
  104. migration-unix.c
  105. migration.c
  106. monitor.c
  107. nbd.c
  108. os-posix.c
  109. os-win32.c
  110. page_cache.c
  111. qapi-schema.json
  112. qdev-monitor.c
  113. qdict-test-data.txt
  114. qemu-bridge-helper.c
  115. qemu-char.c
  116. qemu-coroutine-io.c
  117. qemu-coroutine-lock.c
  118. qemu-coroutine-sleep.c
  119. qemu-coroutine.c
  120. qemu-doc.texi
  121. qemu-img-cmds.hx
  122. qemu-img.c
  123. qemu-img.texi
  124. qemu-io-cmds.c
  125. qemu-io.c
  126. qemu-log.c
  127. qemu-nbd.c
  128. qemu-nbd.texi
  129. qemu-options-wrapper.h
  130. qemu-options.h
  131. qemu-options.hx
  132. qemu-seccomp.c
  133. qemu-tech.texi
  134. qemu-timer.c
  135. qemu.nsi
  136. qemu.sasl
  137. qmp-commands.hx
  138. qmp.c
  139. qtest.c
  140. readline.c
  141. README
  142. rules.mak
  143. savevm.c
  144. spice-qemu-char.c
  145. tcg-runtime.c
  146. tci.c
  147. thread-pool.c
  148. thunk.c
  149. tpm.c
  150. trace-events
  151. translate-all.c
  152. translate-all.h
  153. user-exec.c
  154. VERSION
  155. version.rc
  156. vl.c
  157. xbzrle.c
  158. xen-all.c
  159. xen-mapcache.c
  160. xen-stub.c