bfcea1c661
fs_info::csum_hash gets initialized in btrfs_init_csum_hash() which is
called by open_ctree().
But it only gets freed if open_ctree() fails, not on normal operation.
This leads to a memory leak like the following found by kmemleak:
unreferenced object 0xffff888132cb8720 (size 96):
comm "mount", pid 450, jiffies 4294912436 (age 17.584s)
hex dump (first 32 bytes):
04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000000c9643d4>] crypto_create_tfm+0x2d/0xd0
[<00000000ae577f68>] crypto_alloc_tfm+0x4b/0xb0
[<000000002b5cdf30>] open_ctree+0xb84/0x2060 [btrfs]
[<0000000043204297>] btrfs_mount_root+0x552/0x640 [btrfs]
[<00000000c99b10ea>] legacy_get_tree+0x22/0x40
[<0000000071a6495f>] vfs_get_tree+0x1f/0xc0
[<00000000f180080e>] fc_mount+0x9/0x30
[<000000009e36cebd>] vfs_kern_mount.part.11+0x6a/0x80
[<0000000004594c05>] btrfs_mount+0x174/0x910 [btrfs]
[<00000000c99b10ea>] legacy_get_tree+0x22/0x40
[<0000000071a6495f>] vfs_get_tree+0x1f/0xc0
[<00000000b86e92c5>] do_mount+0x6b0/0x940
[<0000000097464494>] ksys_mount+0x7b/0xd0
[<0000000057213c80>] __x64_sys_mount+0x1c/0x20
[<00000000cb689b5e>] do_syscall_64+0x43/0x130
[<000000002194e289>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Free fs_info::csum_hash in close_ctree() to avoid the memory leak.
Fixes: 6d97c6e31b55 ("btrfs: add boilerplate code for directly including the crypto framework")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.