From 7653b9d87516ed65e112d2273c65eca6f97d0a27 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 23 Mar 2020 11:18:07 +0800 Subject: f2fs: fix potential .flags overflow on 32bit architecture f2fs_inode_info.flags is unsigned long variable, it has 32 bits in 32bit architecture, since we introduced FI_MMAP_FILE flag when we support data compression, we may access memory cross the border of .flags field, corrupting .i_sem field, result in below deadlock. To fix this issue, let's expand .flags as an array to grab enough space to store new flags. Call Trace: __schedule+0x8d0/0x13fc ? mark_held_locks+0xac/0x100 schedule+0xcc/0x260 rwsem_down_write_slowpath+0x3ab/0x65d down_write+0xc7/0xe0 f2fs_drop_nlink+0x3d/0x600 [f2fs] f2fs_delete_inline_entry+0x300/0x440 [f2fs] f2fs_delete_entry+0x3a1/0x7f0 [f2fs] f2fs_unlink+0x500/0x790 [f2fs] vfs_unlink+0x211/0x490 do_unlinkat+0x483/0x520 sys_unlink+0x4a/0x70 do_fast_syscall_32+0x12b/0x683 entry_SYSENTER_32+0xaa/0x102 Fixes: 4c8ff7095bef ("f2fs: support data compression") Tested-by: Ondrej Jirman Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/f2fs/inode.c') diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 44e08bf2e2b4..44582a4db513 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -362,7 +362,7 @@ static int do_read_inode(struct inode *inode) fi->i_flags = le32_to_cpu(ri->i_flags); if (S_ISREG(inode->i_mode)) fi->i_flags &= ~F2FS_PROJINHERIT_FL; - fi->flags = 0; + bitmap_zero(fi->flags, FI_MAX); fi->i_advise = ri->i_advise; fi->i_pino = le32_to_cpu(ri->i_pino); fi->i_dir_level = ri->i_dir_level; -- cgit v1.2.3