From 1b327f7952d760762259b1c11468756638670292 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 18 Dec 2023 08:09:46 +0100 Subject: [PATCH] 4.14-stable patches added patches: ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch --- ...d-size-from-exceeding-ext_max_blocks.patch | 75 +++++++++++++++++++ queue-4.14/series | 1 + 2 files changed, 76 insertions(+) create mode 100644 queue-4.14/ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch diff --git a/queue-4.14/ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch b/queue-4.14/ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch new file mode 100644 index 00000000000..c3cb40d7f21 --- /dev/null +++ b/queue-4.14/ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch @@ -0,0 +1,75 @@ +From 2dcf5fde6dffb312a4bfb8ef940cea2d1f402e32 Mon Sep 17 00:00:00 2001 +From: Baokun Li +Date: Mon, 27 Nov 2023 14:33:13 +0800 +Subject: ext4: prevent the normalized size from exceeding EXT_MAX_BLOCKS + +From: Baokun Li + +commit 2dcf5fde6dffb312a4bfb8ef940cea2d1f402e32 upstream. + +For files with logical blocks close to EXT_MAX_BLOCKS, the file size +predicted in ext4_mb_normalize_request() may exceed EXT_MAX_BLOCKS. +This can cause some blocks to be preallocated that will not be used. +And after [Fixes], the following issue may be triggered: + +========================================================= + kernel BUG at fs/ext4/mballoc.c:4653! + Internal error: Oops - BUG: 00000000f2000800 [#1] SMP + CPU: 1 PID: 2357 Comm: xfs_io 6.7.0-rc2-00195-g0f5cc96c367f + Hardware name: linux,dummy-virt (DT) + pc : ext4_mb_use_inode_pa+0x148/0x208 + lr : ext4_mb_use_inode_pa+0x98/0x208 + Call trace: + ext4_mb_use_inode_pa+0x148/0x208 + ext4_mb_new_inode_pa+0x240/0x4a8 + ext4_mb_use_best_found+0x1d4/0x208 + ext4_mb_try_best_found+0xc8/0x110 + ext4_mb_regular_allocator+0x11c/0xf48 + ext4_mb_new_blocks+0x790/0xaa8 + ext4_ext_map_blocks+0x7cc/0xd20 + ext4_map_blocks+0x170/0x600 + ext4_iomap_begin+0x1c0/0x348 +========================================================= + +Here is a calculation when adjusting ac_b_ex in ext4_mb_new_inode_pa(): + + ex.fe_logical = orig_goal_end - EXT4_C2B(sbi, ex.fe_len); + if (ac->ac_o_ex.fe_logical >= ex.fe_logical) + goto adjust_bex; + +The problem is that when orig_goal_end is subtracted from ac_b_ex.fe_len +it is still greater than EXT_MAX_BLOCKS, which causes ex.fe_logical to +overflow to a very small value, which ultimately triggers a BUG_ON in +ext4_mb_new_inode_pa() because pa->pa_free < len. + +The last logical block of an actual write request does not exceed +EXT_MAX_BLOCKS, so in ext4_mb_normalize_request() also avoids normalizing +the last logical block to exceed EXT_MAX_BLOCKS to avoid the above issue. + +The test case in [Link] can reproduce the above issue with 64k block size. + +Link: https://patchwork.kernel.org/project/fstests/list/?series=804003 +Cc: # 6.4 +Fixes: 93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()") +Signed-off-by: Baokun Li +Reviewed-by: Jan Kara +Link: https://lore.kernel.org/r/20231127063313.3734294-1-libaokun1@huawei.com +Signed-off-by: Theodore Ts'o +Signed-off-by: Greg Kroah-Hartman +--- + fs/ext4/mballoc.c | 4 ++++ + 1 file changed, 4 insertions(+) + +--- a/fs/ext4/mballoc.c ++++ b/fs/ext4/mballoc.c +@@ -3207,6 +3207,10 @@ ext4_mb_normalize_request(struct ext4_al + start = max(start, rounddown(ac->ac_o_ex.fe_logical, + (ext4_lblk_t)EXT4_BLOCKS_PER_GROUP(ac->ac_sb))); + ++ /* avoid unnecessary preallocation that may trigger assertions */ ++ if (start + size > EXT_MAX_BLOCKS) ++ size = EXT_MAX_BLOCKS - start; ++ + /* don't cover already allocated blocks in selected range */ + if (ar->pleft && start <= ar->lleft) { + size -= ar->lleft + 1 - start; diff --git a/queue-4.14/series b/queue-4.14/series index 76012c9984a..64f331e0ae7 100644 --- a/queue-4.14/series +++ b/queue-4.14/series @@ -19,3 +19,4 @@ hid-multitouch-add-quirk-for-honor-glo-gxxx-touchpad.patch asm-generic-qspinlock-fix-queued_spin_value_unlocked.patch net-usb-qmi_wwan-claim-interface-4-for-zte-mf290.patch hid-hid-asus-add-const-to-read-only-outgoing-usb-buf.patch +ext4-prevent-the-normalized-size-from-exceeding-ext_max_blocks.patch -- 2.47.3