Improved robustness of the "showdb" debugging program when it is parsing

corrupt database files.

FossilOrigin-Name: 3eabac2ee50fd70b22a927d3d2934718a15e1f666d8d271b854579156c8b01de

diff --git a/manifest b/manifest
index c0f0a3f4d718e0285e1649dcfe2c3d7b0d8d8344..f51fabc913c2a70e2a55dc1c27d8339344aa994a 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C New\sdbsqlfuzz\scases\sadded\sto\stest/fuzzdata8.db.
-D 2021-04-26T22:30:49.648
+C Improved\srobustness\sof\sthe\s"showdb"\sdebugging\sprogram\swhen\sit\sis\sparsing\ncorrupt\sdatabase\sfiles.
+D 2021-04-26T23:57:02.468
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -1864,7 +1864,7 @@ F tool/replace.tcl 60f91e8dd06ab81f74d213ecbd9c9945f32ac048
 F tool/restore_jrnl.tcl 6957a34f8f1f0f8285e07536225ec3b292a9024a
 F tool/rollback-test.c 9fc98427d1e23e84429d7e6d07d9094fbdec65a5
 F tool/run-speed-test.sh f95d19fd669b68c4c38b6b475242841d47c66076
-F tool/showdb.c 49e810f5c414c792b5bf38cd5557ca9639713ebfef32aaff32faf7cb7ccce513
+F tool/showdb.c d99bd18f8386fd83f8236b1c367e464a6d58e65681f2de25856dfa5076fa67cb
 F tool/showjournal.c 5bad7ae8784a43d2b270d953060423b8bd480818
 F tool/showlocks.c 9cc5e66d4ebbf2d194f39db2527ece92077e86ae627ddd233ee48e16e8142564
 F tool/showshm.c a0ab6ec32dd1f11218ca2a4018f8fb875b59414801ab8ceed8b2e69b7b45a809
@@ -1914,7 +1914,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P f80d7bb2c305c1dd4658767660b33259032c048a91f18c654a6bda7332c54a0c
-R d8e1326693278e6f1513c26703f6c0aa
+P 88d20500c516fe89ad1cd42f7366ca190c3790f911f11ab332b86b675f5f69ba
+R a7a438a7a1e4a8c7f93ba3c58bbec3f4
 U drh
-Z bb52e9bce99951a04289010ee988307c
+Z 323bfb66712236d14601f16d2826d127

diff --git a/manifest.uuid b/manifest.uuid
index 703532bf7ce6db6c2f9e4fd5144062a37cca216e..1cf0c55c7ada6ef7cd34681b7e67287672db851d 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-88d20500c516fe89ad1cd42f7366ca190c3790f911f11ab332b86b675f5f69ba
\ No newline at end of file
+3eabac2ee50fd70b22a927d3d2934718a15e1f666d8d271b854579156c8b01de
\ No newline at end of file

diff --git a/tool/showdb.c b/tool/showdb.c
index 09c4d9de44cb119c1ce51161c76c67d9d2091382..b4b751e5883f3ea859504addc1dda1833e16f57d 100644 (file)
--- a/tool/showdb.c
+++ b/tool/showdb.c
@@ -912,10 +912,19 @@ static void page_usage_btree(
     int cellstart = hdr+12;
     u32 child;
     for(i=0; i<nCell; i++){
+      u32 cellidx;
       u32 ofst;
 
-      ofst = cellstart + i*2;
-      ofst = a[ofst]*256 + a[ofst+1];
+      cellidx = cellstart + i*2;
+      if( cellidx+1 >= g.pagesize ){
+        page_usage_msg(pgno, "too many cells");
+        break;
+      }
+      ofst = a[cellidx]*256 + a[cellidx+1];
+      if( ofst<cellidx+2 || ofst+4>=g.pagesize ){
+        page_usage_msg(pgno, "cell %d out of bounds", i);
+        continue;
+      }
       child = decodeInt32(a+ofst);
       page_usage_btree(child, pgno, i, zName);
     }