summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorShijie Luo <luoshijie1@huawei.com>2020-02-10 20:17:52 -0500
committerBen Hutchings <ben@decadent.org.uk>2020-06-11 19:05:55 +0100
commit53b7a2eb6f94f439bce973593ce177592d34c63f (patch)
tree66850350109e98947018edc13be936c5f01909fd
parent71bfaf9e30125ec5b408fd328e412abf3b23214d (diff)
downloadlinux-stable-53b7a2eb6f94f439bce973593ce177592d34c63f.tar.gz
linux-stable-53b7a2eb6f94f439bce973593ce177592d34c63f.tar.bz2
linux-stable-53b7a2eb6f94f439bce973593ce177592d34c63f.zip
ext4: add cond_resched() to ext4_protect_reserved_inode
commit af133ade9a40794a37104ecbcc2827c0ea373a3c upstream. When journal size is set too big by "mkfs.ext4 -J size=", or when we mount a crafted image to make journal inode->i_size too big, the loop, "while (i < num)", holds cpu too long. This could cause soft lockup. [ 529.357541] Call trace: [ 529.357551] dump_backtrace+0x0/0x198 [ 529.357555] show_stack+0x24/0x30 [ 529.357562] dump_stack+0xa4/0xcc [ 529.357568] watchdog_timer_fn+0x300/0x3e8 [ 529.357574] __hrtimer_run_queues+0x114/0x358 [ 529.357576] hrtimer_interrupt+0x104/0x2d8 [ 529.357580] arch_timer_handler_virt+0x38/0x58 [ 529.357584] handle_percpu_devid_irq+0x90/0x248 [ 529.357588] generic_handle_irq+0x34/0x50 [ 529.357590] __handle_domain_irq+0x68/0xc0 [ 529.357593] gic_handle_irq+0x6c/0x150 [ 529.357595] el1_irq+0xb8/0x140 [ 529.357599] __ll_sc_atomic_add_return_acquire+0x14/0x20 [ 529.357668] ext4_map_blocks+0x64/0x5c0 [ext4] [ 529.357693] ext4_setup_system_zone+0x330/0x458 [ext4] [ 529.357717] ext4_fill_super+0x2170/0x2ba8 [ext4] [ 529.357722] mount_bdev+0x1a8/0x1e8 [ 529.357746] ext4_mount+0x44/0x58 [ext4] [ 529.357748] mount_fs+0x50/0x170 [ 529.357752] vfs_kern_mount.part.9+0x54/0x188 [ 529.357755] do_mount+0x5ac/0xd78 [ 529.357758] ksys_mount+0x9c/0x118 [ 529.357760] __arm64_sys_mount+0x28/0x38 [ 529.357764] el0_svc_common+0x78/0x130 [ 529.357766] el0_svc_handler+0x38/0x78 [ 529.357769] el0_svc+0x8/0xc [ 541.356516] watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [mount:18674] Link: https://lore.kernel.org/r/20200211011752.29242-1-luoshijie1@huawei.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Shijie Luo <luoshijie1@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-rw-r--r--fs/ext4/block_validity.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c
index 2a7efb6e1986..c6836e6726ae 100644
--- a/fs/ext4/block_validity.c
+++ b/fs/ext4/block_validity.c
@@ -153,6 +153,7 @@ static int ext4_protect_reserved_inode(struct super_block *sb, u32 ino)
return PTR_ERR(inode);
num = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
while (i < num) {
+ cond_resched();
map.m_lblk = i;
map.m_len = num - i;
n = ext4_map_blocks(NULL, inode, &map, 0);