From 06b83bcda9164d723efbfdafb70f90c69c30eae4 Mon Sep 17 00:00:00 2001 From: Hyeongseok Kim Date: Sat, 22 May 2021 11:57:07 +0000 Subject: [PATCH] exfat: fix erroneous discard when clear cluster bit stable inclusion from stable-5.10.36 commit 11e3ff7e164a69b8807a9c1066c1b6adbb6033e1 bugzilla: 51867 CVE: NA -------------------------------- commit 77edfc6e51055b61cae2f54c8e6c3bb7c762e4fe upstream. If mounted with discard option, exFAT issues discard command when clear cluster bit to remove file. But the input parameter of cluster-to-sector calculation is abnormally added by reserved cluster size which is 2, leading to discard unrelated sectors included in target+2 cluster. With fixing this, remove the wrong comments in set/clear/find bitmap functions. Fixes: 1e49a94cf707 ("exfat: add bitmap operations") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Hyeongseok Kim Acked-by: Sungjong Seo Signed-off-by: Namjae Jeon Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chen Jun Acked-by: Weilong Chen Signed-off-by: Zheng Zengkai --- fs/exfat/balloc.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c index a987919686c0..579c10f57c2b 100644 --- a/fs/exfat/balloc.c +++ b/fs/exfat/balloc.c @@ -141,10 +141,6 @@ void exfat_free_bitmap(struct exfat_sb_info *sbi) kfree(sbi->vol_amap); } -/* - * If the value of "clu" is 0, it means cluster 2 which is the first cluster of - * the cluster heap. - */ int exfat_set_bitmap(struct inode *inode, unsigned int clu) { int i, b; @@ -162,10 +158,6 @@ int exfat_set_bitmap(struct inode *inode, unsigned int clu) return 0; } -/* - * If the value of "clu" is 0, it means cluster 2 which is the first cluster of - * the cluster heap. - */ void exfat_clear_bitmap(struct inode *inode, unsigned int clu) { int i, b; @@ -186,8 +178,7 @@ void exfat_clear_bitmap(struct inode *inode, unsigned int clu) int ret_discard; ret_discard = sb_issue_discard(sb, - exfat_cluster_to_sector(sbi, clu + - EXFAT_RESERVED_CLUSTERS), + exfat_cluster_to_sector(sbi, clu), (1 << sbi->sect_per_clus_bits), GFP_NOFS, 0); if (ret_discard == -EOPNOTSUPP) { -- GitLab