| Message ID | 1467182801-16948-1-git-send-email-kernel@kyup.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On 06/29/2016 02:46 AM, Nikolay Borisov wrote: > The code flow in btrfs_new_inode allows for btrfs_evict_inode to be > called with not fully initialised inode (e.g. ->root member not > being set). This can happen when btrfs_set_inode_index in > btrfs_new_inode fails, which in turn would call iput for the newly > allocated inode. This in turn leads to vfs calling into btrfs_evict_inode. > This leads to null pointer dereference. To handle this situation check whether > the passed inode has root set and just free it in case it doesn't. > > Signed-off-by: Nikolay Borisov <kernel@kyup.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 4421954720b8..b51723811d01 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5159,11 +5159,18 @@ void btrfs_evict_inode(struct inode *inode) struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_block_rsv *rsv, *global_rsv; int steal_from_global = 0; - u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); + u64 min_size; int ret; trace_btrfs_inode_evict(inode); + if (!root) { + kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); + return; + } + + min_size = btrfs_calc_trunc_metadata_size(root, 1); + evict_inode_truncate_pages(inode); if (inode->i_nlink &&
The code flow in btrfs_new_inode allows for btrfs_evict_inode to be called with not fully initialised inode (e.g. ->root member not being set). This can happen when btrfs_set_inode_index in btrfs_new_inode fails, which in turn would call iput for the newly allocated inode. This in turn leads to vfs calling into btrfs_evict_inode. This leads to null pointer dereference. To handle this situation check whether the passed inode has root set and just free it in case it doesn't. Signed-off-by: Nikolay Borisov <kernel@kyup.com> --- fs/btrfs/inode.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) Hello, I belive this is fixes the issue reported in http://thread.gmane.org/gmane.comp.file-systems.btrfs/57809