block: check for existing device IDs in external_snapshot_prepare()

The 'snapshot-node-name' parameter of blockdev-snapshot-sync allows
setting the node name of the image that is going to be created.

Before creating the image, external_snapshot_prepare() checks that the
name is not already being used. The check is however incomplete since
it only considers existing node names, but node names must not clash
with device IDs either because they share the same namespace.

If the user attempts to create a snapshot using the name of an
existing device for the 'snapshot-node-name' parameter the operation
will eventually fail, but only after the new image has been created.

This patch replaces bdrv_find_node() with bdrv_lookup_bs() to extend
the check to existing device IDs, and thus detect possible name
clashes before the new image is created.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
1 file changed
tree: 681383c1863e96889ec222f507ffa45510cb8321
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. contrib/
  6. crypto/
  7. default-configs/
  8. disas/
  9. docs/
  10. fpu/
  11. fsdev/
  12. gdb-xml/
  13. hw/
  14. include/
  15. libdecnumber/
  16. linux-headers/
  17. linux-user/
  18. migration/
  19. net/
  20. pc-bios/
  21. po/
  22. qapi/
  23. qga/
  24. qobject/
  25. qom/
  26. replay/
  27. roms/
  28. scripts/
  29. slirp/
  30. stubs/
  31. target-alpha/
  32. target-arm/
  33. target-cris/
  34. target-i386/
  35. target-lm32/
  36. target-m68k/
  37. target-microblaze/
  38. target-mips/
  39. target-moxie/
  40. target-openrisc/
  41. target-ppc/
  42. target-s390x/
  43. target-sh4/
  44. target-sparc/
  45. target-tilegx/
  46. target-tricore/
  47. target-unicore32/
  48. target-xtensa/
  49. tcg/
  50. tests/
  51. trace/
  52. ui/
  53. util/
  54. .dir-locals.el
  55. .exrc
  56. .gitignore
  57. .gitmodules
  58. .mailmap
  59. .travis.yml
  60. accel.c
  61. aio-posix.c
  62. aio-win32.c
  63. arch_init.c
  64. async.c
  65. balloon.c
  66. block.c
  67. blockdev-nbd.c
  68. blockdev.c
  69. blockjob.c
  70. bootdevice.c
  71. bt-host.c
  72. bt-vhci.c
  73. Changelog
  74. CODING_STYLE
  75. configure
  76. COPYING
  77. COPYING.LIB
  78. cpu-exec-common.c
  79. cpu-exec.c
  80. cpus.c
  81. cputlb.c
  82. device-hotplug.c
  83. device_tree.c
  84. disas.c
  85. dma-helpers.c
  86. dump.c
  87. exec.c
  88. gdbstub.c
  89. HACKING
  90. hmp-commands-info.hx
  91. hmp-commands.hx
  92. hmp.c
  93. hmp.h
  94. iohandler.c
  95. ioport.c
  96. iothread.c
  97. kvm-all.c
  98. kvm-stub.c
  99. LICENSE
  100. main-loop.c
  101. MAINTAINERS
  102. Makefile
  103. Makefile.objs
  104. Makefile.target
  105. memory.c
  106. memory_mapping.c
  107. module-common.c
  108. monitor.c
  109. nbd.c
  110. numa.c
  111. os-posix.c
  112. os-win32.c
  113. page_cache.c
  114. qapi-schema.json
  115. qdev-monitor.c
  116. qdict-test-data.txt
  117. qemu-bridge-helper.c
  118. qemu-char.c
  119. qemu-doc.texi
  120. qemu-ga.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. qjson.c
  138. qmp-commands.hx
  139. qmp.c
  140. qtest.c
  141. README
  142. rules.mak
  143. softmmu_template.h
  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. translate-common.c
  154. user-exec.c
  155. VERSION
  156. version.rc
  157. vl.c
  158. xen-common-stub.c
  159. xen-common.c
  160. xen-hvm-stub.c
  161. xen-hvm.c
  162. xen-mapcache.c