Thread: pgsql: Fix unsafe access to BufferDescriptors
Fix unsafe access to BufferDescriptors When considering a local buffer, the GetBufferDescriptor() call in BufferGetLSNAtomic() would be retrieving a shared buffer with a bad buffer ID. Since the code checks whether the buffer is shared before using the retrieved BufferDesc, this issue did not lead to any malfunction. Nonetheless this seems like trouble waiting to happen, so fix it by ensuring that GetBufferDescriptor() is only called when we know the buffer is shared. Author: Tender Wang <tndrwang@gmail.com> Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com> Reviewed-by: Richard Guo <guofenglinux@gmail.com> Discussion: https://postgr.es/m/CAHewXNku-o46-9cmUgyv6LkSZ25doDrWq32p=oz9kfD8ovVJMg@mail.gmail.com Backpatch-through: 13 Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/a38a7ad51ec8dc558d71806d7f1aee986723ccbc Modified Files -------------- src/backend/storage/buffer/bufmgr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)