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author | Chao Yu <chao2.yu@samsung.com> | 2014-07-07 03:39:32 +0200 |
---|---|---|
committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2014-07-09 14:59:55 +0200 |
commit | 50e1f8d22199b557337b3d1ec8520e4c5aa5c76e (patch) | |
tree | efae0ff87090bc8c6707eb2385ef2374f1ec256f /fs | |
parent | f2fs: check bdi->dirty_exceeded when trying to skip data writes (diff) | |
download | linux-50e1f8d22199b557337b3d1ec8520e4c5aa5c76e.tar.xz linux-50e1f8d22199b557337b3d1ec8520e4c5aa5c76e.zip |
f2fs: avoid to access NULL pointer in issue_flush_thread
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=75861
Denis 2014-05-10 11:28:59 UTC reported:
"F2FS-fs (mmcblk0p28): mounting..
Unable to handle kernel NULL pointer dereference at virtual address 00000018
...
[<c0a2f678>] (_raw_spin_lock+0x3c/0x70) from [<c03a0330>] (issue_flush_thread+0x50/0x17c)
[<c03a0330>] (issue_flush_thread+0x50/0x17c) from [<c01b4064>] (kthread+0x98/0xa4)
[<c01b4064>] (kthread+0x98/0xa4) from [<c0108060>] (kernel_thread_exit+0x0/0x8)"
This patch assign cmd_control_info in sm_info before issue_flush_thread is being
created, so this make sure that issue flush thread will have no chance to access
invalid info in fcc.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/f2fs/segment.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index b22d5a0652bb..d04613df710a 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -272,14 +272,15 @@ int create_flush_cmd_control(struct f2fs_sb_info *sbi) return -ENOMEM; spin_lock_init(&fcc->issue_lock); init_waitqueue_head(&fcc->flush_wait_queue); + sbi->sm_info->cmd_control_info = fcc; fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi, "f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev)); if (IS_ERR(fcc->f2fs_issue_flush)) { err = PTR_ERR(fcc->f2fs_issue_flush); kfree(fcc); + sbi->sm_info->cmd_control_info = NULL; return err; } - sbi->sm_info->cmd_control_info = fcc; return err; } |