linux/fs/configfs
Sishuai Gong c42dd069be configfs: fix a race in configfs_lookup()
When configfs_lookup() is executing list_for_each_entry(),
it is possible that configfs_dir_lseek() is calling list_del().
Some unfortunate interleavings of them can cause a kernel NULL
pointer dereference error

Thread 1                  Thread 2
//configfs_dir_lseek()    //configfs_lookup()
list_del(&cursor->s_sibling);
                         list_for_each_entry(sd, ...)

Fix this by grabbing configfs_dirent_lock in configfs_lookup()
while iterating ->s_children.

Signed-off-by: Sishuai Gong <sishuai@purdue.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-25 07:58:49 +02:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
configfs_internal.h treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
dir.c configfs: fix a race in configfs_lookup() 2021-08-25 07:58:49 +02:00
file.c configfs: restore the kernel v5.13 text attribute write behavior 2021-08-09 16:56:00 +02:00
inode.c fs: move ramfs_aops to libfs 2021-06-29 10:53:48 -07:00
item.c treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
mount.c treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
symlink.c treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00