From 09beadf289d6e300553e60d6e76f13c0427ecab3 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Wed, 27 Jul 2022 22:51:05 +0800 Subject: f2fs: fix to do sanity check on segment type in build_sit_entries() As Wenqing Liu reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216285 RIP: 0010:memcpy_erms+0x6/0x10 f2fs_update_meta_page+0x84/0x570 [f2fs] change_curseg.constprop.0+0x159/0xbd0 [f2fs] f2fs_do_replace_block+0x5c7/0x18a0 [f2fs] f2fs_replace_block+0xeb/0x180 [f2fs] recover_data+0x1abd/0x6f50 [f2fs] f2fs_recover_fsync_data+0x12ce/0x3250 [f2fs] f2fs_fill_super+0x4459/0x6190 [f2fs] mount_bdev+0x2cf/0x3b0 legacy_get_tree+0xed/0x1d0 vfs_get_tree+0x81/0x2b0 path_mount+0x47e/0x19d0 do_mount+0xce/0xf0 __x64_sys_mount+0x12c/0x1a0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd The root cause is segment type is invalid, so in f2fs_do_replace_block(), f2fs accesses f2fs_sm_info::curseg_array with out-of-range segment type, result in accessing invalid curseg->sum_blk during memcpy in f2fs_update_meta_page(). Fix this by adding sanity check on segment type in build_sit_entries(). Reported-by: Wenqing Liu Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/segment.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'fs/f2fs/segment.c') diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 51da73b27a45..7b1d2c29aba6 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -4375,6 +4375,12 @@ static int build_sit_entries(struct f2fs_sb_info *sbi) return err; seg_info_from_raw_sit(se, &sit); + if (se->type >= NR_PERSISTENT_LOG) { + f2fs_err(sbi, "Invalid segment type: %u, segno: %u", + se->type, start); + return -EFSCORRUPTED; + } + sit_valid_blocks[SE_PAGETYPE(se)] += se->valid_blocks; if (f2fs_block_unit_discard(sbi)) { @@ -4423,6 +4429,13 @@ static int build_sit_entries(struct f2fs_sb_info *sbi) break; seg_info_from_raw_sit(se, &sit); + if (se->type >= NR_PERSISTENT_LOG) { + f2fs_err(sbi, "Invalid segment type: %u, segno: %u", + se->type, start); + err = -EFSCORRUPTED; + break; + } + sit_valid_blocks[SE_PAGETYPE(se)] += se->valid_blocks; if (f2fs_block_unit_discard(sbi)) { -- cgit v1.2.3