| Message ID | 20180514070310.27197-2-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/14/2018 03:03 PM, Qu Wenruo wrote: > There is one report of compressed extent happens in btrfs, but has no > csum and then leads to possible decompress error screwing up kernel > memory. > > Although it's a kernel bug, and won't cause problem until compressed > data get corrupted, let's catch such problem in advance. > > This patch will catch any unexpected compressed extent with: > > 1) 0 or less than expected csum > > 2) nodatasum flag set in the inode item > > This is for lowmem mode. > > Reported-by: James Harvey <jamespharvey20@gmail.com> > Issue: #134 > Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com> > --- > check/mode-lowmem.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/check/mode-lowmem.c b/check/mode-lowmem.c > index dac3201b7d99..8e6d5e8de12a 100644 > --- a/check/mode-lowmem.c > +++ b/check/mode-lowmem.c > @@ -1543,6 +1543,24 @@ static int check_file_extent(struct btrfs_root *root, struct btrfs_key *fkey, > csum_found); > } > } > + /* > + * Extra check for compressed extents. > + * Btrfs doesn't allow NODATASUM and compressed extent co-exist, thus > + * all compressed extent should have csum. > + */ > + if (compressed && csum_found < search_len) { > + error( > +"root %llu EXTENT_DATA[%llu %llu] compressed extent must have csum, but only %llu bytes has csum, expect %llu", > + root->objectid, fkey->objectid, fkey->offset, csum_found, > + search_len); > + err |= CSUM_ITEM_MISSING; > + } > + if (compressed && nodatasum) { > + error( > +"root %llu EXTENT_DATA[%llu %llu] is compressed, but inode flag doesn't allow it", > + root->objectid, fkey->objectid, fkey->offset); > + err |= FILE_EXTENT_ERROR; > + } > > /* Check EXTENT_DATA hole */ > if (!no_holes && *end != fkey->offset) { >
diff --git a/check/mode-lowmem.c b/check/mode-lowmem.c index dac3201b7d99..8e6d5e8de12a 100644 --- a/check/mode-lowmem.c +++ b/check/mode-lowmem.c @@ -1543,6 +1543,24 @@ static int check_file_extent(struct btrfs_root *root, struct btrfs_key *fkey, csum_found); } } + /* + * Extra check for compressed extents. + * Btrfs doesn't allow NODATASUM and compressed extent co-exist, thus + * all compressed extent should have csum. + */ + if (compressed && csum_found < search_len) { + error( +"root %llu EXTENT_DATA[%llu %llu] compressed extent must have csum, but only %llu bytes has csum, expect %llu", + root->objectid, fkey->objectid, fkey->offset, csum_found, + search_len); + err |= CSUM_ITEM_MISSING; + } + if (compressed && nodatasum) { + error( +"root %llu EXTENT_DATA[%llu %llu] is compressed, but inode flag doesn't allow it", + root->objectid, fkey->objectid, fkey->offset); + err |= FILE_EXTENT_ERROR; + } /* Check EXTENT_DATA hole */ if (!no_holes && *end != fkey->offset) {
There is one report of compressed extent happens in btrfs, but has no csum and then leads to possible decompress error screwing up kernel memory. Although it's a kernel bug, and won't cause problem until compressed data get corrupted, let's catch such problem in advance. This patch will catch any unexpected compressed extent with: 1) 0 or less than expected csum 2) nodatasum flag set in the inode item This is for lowmem mode. Reported-by: James Harvey <jamespharvey20@gmail.com> Issue: #134 Signed-off-by: Qu Wenruo <wqu@suse.com> --- check/mode-lowmem.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)