Re: pg_verifybackup: TAR format backup verification

Piling on a bit ... Coverity reported the following issues in
this new code. I have not analyzed them to see if they're
real problems.

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*** CID 1620458: Resource leaks (RESOURCE_LEAK)
/srv/coverity/git/pgsql-git/postgresql/src/bin/pg_verifybackup/pg_verifybackup.c: 1025 in verify_tar_file()
1019 relpath);
1020
1021 /* Close the file. */
1022 if (close(fd) != 0)
1023 report_backup_error(context, "could not close file \"%s\": %m",
1024 relpath);
>>> CID 1620458: Resource leaks (RESOURCE_LEAK)
>>> Variable "buffer" going out of scope leaks the storage it points to.
1025 }
1026
1027 /*
1028 * Scan the hash table for entries where the 'matched' flag is not set; report
1029 * that such files are present in the manifest but not on disk.
1030 */

________________________________________________________________________________________________________
*** CID 1620457: Memory - illegal accesses (OVERRUN)
/srv/coverity/git/pgsql-git/postgresql/src/bin/pg_verifybackup/astreamer_verify.c: 349 in member_copy_control_data()
343 */
344 if (mystreamer->control_file_bytes <= sizeof(ControlFileData))
345 {
346 int remaining;
347
348 remaining = sizeof(ControlFileData) - mystreamer->control_file_bytes;
>>> CID 1620457: Memory - illegal accesses (OVERRUN)
>>> Overrunning array of 296 bytes at byte offset 296 by dereferencing pointer "(char *)&mystreamer->control_file + mystreamer->control_file_bytes".
349 memcpy(((char *) &mystreamer->control_file)
350 + mystreamer->control_file_bytes,
351 data, Min(len, remaining));
352 }
353
354 /* Remember how many bytes we saw, even if we didn't buffer them. */

________________________________________________________________________________________________________
*** CID 1620456: Null pointer dereferences (FORWARD_NULL)
/srv/coverity/git/pgsql-git/postgresql/src/bin/pg_verifybackup/pg_verifybackup.c: 939 in precheck_tar_backup_file()
933 "file \"%s\" is not expected in a tar format backup",
934 relpath);
935 tblspc_oid = (Oid) num;
936 }
937
938 /* Now, check the compression type of the tar */
>>> CID 1620456: Null pointer dereferences (FORWARD_NULL)
>>> Passing null pointer "suffix" to "strcmp", which dereferences it.
939 if (strcmp(suffix, ".tar") == 0)
940 compress_algorithm = PG_COMPRESSION_NONE;
941 else if (strcmp(suffix, ".tgz") == 0)
942 compress_algorithm = PG_COMPRESSION_GZIP;
943 else if (strcmp(suffix, ".tar.gz") == 0)
944 compress_algorithm = PG_COMPRESSION_GZIP;

regards, tom lane