5 Commits

Author	SHA1	Message	Date
Al Viro	a2bbe66493	constify dentry argument of dentry_path()/dentry_path_raw() ... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>	2021-03-21 11:43:58 -04:00
Andrii Nakryiko	09cad07547	fs: fix NULL dereference due to data race in prepend_path() ... Fix data race in prepend_path() with re-reading mnt->mnt_ns twice without holding the lock. is_mounted() does check for NULL, but is_anon_ns(mnt->mnt_ns) might re-read the pointer again which could be NULL already, if in between reads one of kern_unmount()/kern_unmount_array()/umount_tree() sets mnt->mnt_ns to NULL. This is seen in production with the following stack trace: BUG: kernel NULL pointer dereference, address: 0000000000000048 ... RIP: 0010:prepend_path.isra.4+0x1ce/0x2e0 Call Trace: d_path+0xe6/0x150 proc_pid_readlink+0x8f/0x100 vfs_readlink+0xf8/0x110 do_readlinkat+0xfd/0x120 __x64_sys_readlinkat+0x1a/0x20 do_syscall_64+0x42/0x110 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: f2683bd8d5 ("[PATCH] fix d_absolute_path() interplay with fsmount()") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>	2020-10-14 14:54:45 -07:00
Al Viro	f2683bd8d5	[PATCH] fix d_absolute_path() interplay with fsmount() ... stuff in anon namespace should be treated as unattached. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>	2019-08-30 19:31:09 -04:00
Al Viro	7e5f7bb08b	unexport simple_dname() ... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>	2019-05-21 08:23:41 +01:00
Al Viro	7a5cf791a7	split d_path() and friends into a separate file ... Those parts of fs/dcache.c are pretty much self-contained. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>	2018-03-29 15:07:46 -04:00