Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.7 36/45] ext4: fix memory leak in ext4_insert_range() | Date | Fri, 21 Oct 2016 11:17:56 +0200 |
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4.7-stable review patch. If anyone has any objections, please let me know.
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From: Fabian Frederick <fabf@skynet.be>
commit edf15aa180d7b98fe16bd3eda42f9dd0e60dee20 upstream.
Running xfstests generic/013 with kmemleak gives the following:
unreferenced object 0xffff8801d3d27de0 (size 96): comm "fsstress", pid 4941, jiffies 4294860168 (age 53.485s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff818eaaf3>] kmemleak_alloc+0x23/0x40 [<ffffffff81179805>] __kmalloc+0xf5/0x1d0 [<ffffffff8122ef5c>] ext4_find_extent+0x1ec/0x2f0 [<ffffffff8123530c>] ext4_insert_range+0x34c/0x4a0 [<ffffffff81235942>] ext4_fallocate+0x4e2/0x8b0 [<ffffffff81181334>] vfs_fallocate+0x134/0x210 [<ffffffff8118203f>] SyS_fallocate+0x3f/0x60 [<ffffffff818efa9b>] entry_SYSCALL_64_fastpath+0x13/0x8f [<ffffffffffffffff>] 0xffffffffffffffff
Problem seems mitigated by dropping refs and freeing path when there's no path[depth].p_ext
Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- fs/ext4/extents.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -5734,6 +5734,9 @@ int ext4_insert_range(struct inode *inod up_write(&EXT4_I(inode)->i_data_sem); goto out_stop; } + } else { + ext4_ext_drop_refs(path); + kfree(path); } ret = ext4_es_remove_extent(inode, offset_lblk,
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