On Mon, Apr 02, 2018 at 06:47:32PM +0800, Qu Wenruo wrote: > On 2018年03月28日 23:49, David Sterba wrote: > > On Tue, Mar 27, 2018 at 08:44:19PM +0800, Qu Wenruo wrote: > >> We have several reports about node pointer points to incorrect child > >> tree blocks, which could have even wrong owner and level but still with > >> valid generation and checksum. > >> > >> Although btrfs check could handle it and print error message like: > >> leaf parent key incorrect 60670574592 > >> > >> Kernel doesn't have enough check on this type of corruption correctly. > >> At least add such check to read_tree_block() and btrfs_read_buffer(), > >> where we need two new parameters @level and @first_key to verify the > >> child tree block. > >> > >> The new @level check is mandatory and all call sites are already > >> modified to extract expected level from its call chain. > >> > >> While @first_key is optional, the following call sites are skipping such > >> check: > >> 1) Root node/leaf > >> As ROOT_ITEM doesn't contain the first key, skip @first_key check. > >> 2) Direct backref > >> Only parent bytenr and level is known and we need to resolve the key > >> all by ourselves, skip @first_key check. > >> > >> Another note of this verification is, it needs extra info from nodeptr > >> or ROOT_ITEM, so it can't fit into current tree-checker framework, which > >> is limited to node/leaf boundary. > >> > >> Signed-off-by: Qu Wenruo <w...@suse.com> > >> --- > >> changelog: > >> v2: > >> Make @level check mandatory, suggesed by Jeff and Nikolay. > >> Change parameter order as @level is now mandatory, put it in front of > >> @first_key. > >> Change verify_parent_level() to verify_key_level() to avoid confusion > >> on the @level parameter. > >> Add btrfs_error() output for CONFIG_BTRFS_DEBUG to help debugging. > > > > That's much better overall, thanks. Adding it to next. > > Nikolay reported a case where @first_key check seems to cause false alert. > (Although my xfstests check hasn't exposed it yet) > > Please discard this patch since it has the possibility to cause false > alert for btrfs core functionality.
Too late, the patch is in master now, so we need to fix it. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html