From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752896AbcAEUnb (ORCPT ); Tue, 5 Jan 2016 15:43:31 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44678 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752160AbcAETqe (ORCPT ); Tue, 5 Jan 2016 14:46:34 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Jaegeuk Kim , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 039/211] f2fs crypto: allocate buffer for decrypting filename Date: Tue, 5 Jan 2016 11:42:27 -0800 Message-Id: <1452023119-25647-40-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1452023119-25647-1-git-send-email-kamal@canonical.com> References: <1452023119-25647-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Jaegeuk Kim commit 569cf1876a32e574ba8a7fb825cd91bafd003882 upstream. We got dentry pages from high_mem, and its address space directly goes into the decryption path via f2fs_fname_disk_to_usr. But, sg_init_one assumes the address is not from high_mem, so we can get this panic since it doesn't call kmap_high but kunmap_high is triggered at the end. kernel BUG at ../../../../../../kernel/mm/highmem.c:290! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kunmap_high+0xb0/0xb8) from [] (__kunmap_atomic+0xa0/0xa4) (__kunmap_atomic+0xa0/0xa4) from [] (blkcipher_walk_done+0x128/0x1ec) (blkcipher_walk_done+0x128/0x1ec) from [] (crypto_cbc_decrypt+0xc0/0x170) (crypto_cbc_decrypt+0xc0/0x170) from [] (crypto_cts_decrypt+0xc0/0x114) (crypto_cts_decrypt+0xc0/0x114) from [] (async_decrypt+0x40/0x48) (async_decrypt+0x40/0x48) from [] (f2fs_fname_disk_to_usr+0x124/0x304) (f2fs_fname_disk_to_usr+0x124/0x304) from [] (f2fs_fill_dentries+0xac/0x188) (f2fs_fill_dentries+0xac/0x188) from [] (f2fs_readdir+0x1f0/0x300) (f2fs_readdir+0x1f0/0x300) from [] (vfs_readdir+0x90/0xb4) (vfs_readdir+0x90/0xb4) from [] (SyS_getdents64+0x64/0xcc) (SyS_getdents64+0x64/0xcc) from [] (ret_fast_syscall+0x0/0x30) Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Kamal Mostafa --- fs/f2fs/dir.c | 13 ++++++++++--- fs/f2fs/namei.c | 10 +++++++++- 2 files changed, 19 insertions(+), 4 deletions(-) diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index a34ebd8..710c703 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -787,7 +787,6 @@ bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, else d_type = DT_UNKNOWN; - /* encrypted case */ de_name.name = d->filename[bit_pos]; de_name.len = le16_to_cpu(de->name_len); @@ -795,12 +794,20 @@ bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, int save_len = fstr->len; int ret; + de_name.name = kmalloc(de_name.len, GFP_NOFS); + if (!de_name.name) + return false; + + memcpy(de_name.name, d->filename[bit_pos], de_name.len); + ret = f2fs_fname_disk_to_usr(d->inode, &de->hash_code, &de_name, fstr); - de_name = *fstr; - fstr->len = save_len; + kfree(de_name.name); if (ret < 0) return true; + + de_name = *fstr; + fstr->len = save_len; } if (!dir_emit(ctx, de_name.name, de_name.len, diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index fdbae21..ce4cbe8 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -940,8 +940,13 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cook /* Symlink is encrypted */ sd = (struct f2fs_encrypted_symlink_data *)caddr; - cstr.name = sd->encrypted_path; cstr.len = le16_to_cpu(sd->len); + cstr.name = kmalloc(cstr.len, GFP_NOFS); + if (!cstr.name) { + res = -ENOMEM; + goto errout; + } + memcpy(cstr.name, sd->encrypted_path, cstr.len); /* this is broken symlink case */ if (cstr.name[0] == 0 && cstr.len == 0) { @@ -963,6 +968,8 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cook if (res < 0) goto errout; + kfree(cstr.name); + paddr = pstr.name; /* Null-terminate the name */ @@ -972,6 +979,7 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cook page_cache_release(cpage); return *cookie = paddr; errout: + kfree(cstr.name); f2fs_fname_crypto_free_buffer(&pstr); kunmap(cpage); page_cache_release(cpage); -- 1.9.1