6.1-stable review patch. If anyone has any objections, please let me know.
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From: Yuezhang Mo Yuezhang.Mo@sony.com
commit a3ff29a95fde16906304455aa8c0bd84eb770258 upstream.
In special cases, a file or a directory may occupied more than 19 directory entries, pre-allocating 3 bh is not enough. Such as - Support vendor secondary directory entry in the future. - Since file directory entry is damaged, the SecondaryCount field is bigger than 18.
So this commit supports dynamic allocation of bh.
Signed-off-by: Yuezhang Mo Yuezhang.Mo@sony.com Reviewed-by: Andy Wu Andy.Wu@sony.com Reviewed-by: Aoyama Wataru wataru.aoyama@sony.com Reviewed-by: Sungjong Seo sj1557.seo@samsung.com Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/exfat/dir.c | 15 +++++++++++++++ fs/exfat/exfat_fs.h | 5 ++++- 2 files changed, 19 insertions(+), 1 deletion(-)
--- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -613,6 +613,10 @@ int exfat_free_dentry_set(struct exfat_e bforget(es->bh[i]); else brelse(es->bh[i]); + + if (IS_DYNAMIC_ES(es)) + kfree(es->bh); + kfree(es); return err; } @@ -845,6 +849,7 @@ struct exfat_entry_set_cache *exfat_get_ /* byte offset in sector */ off = EXFAT_BLK_OFFSET(byte_offset, sb); es->start_off = off; + es->bh = es->__bh;
/* sector offset in cluster */ sec = EXFAT_B_TO_BLK(byte_offset, sb); @@ -864,6 +869,16 @@ struct exfat_entry_set_cache *exfat_get_ es->num_entries = num_entries;
num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb); + if (num_bh > ARRAY_SIZE(es->__bh)) { + es->bh = kmalloc_array(num_bh, sizeof(*es->bh), GFP_KERNEL); + if (!es->bh) { + brelse(bh); + kfree(es); + return NULL; + } + es->bh[0] = bh; + } + for (i = 1; i < num_bh; i++) { /* get the next sector */ if (exfat_is_last_sector_in_cluster(sbi, sec)) { --- a/fs/exfat/exfat_fs.h +++ b/fs/exfat/exfat_fs.h @@ -169,10 +169,13 @@ struct exfat_entry_set_cache { bool modified; unsigned int start_off; int num_bh; - struct buffer_head *bh[DIR_CACHE_SIZE]; + struct buffer_head *__bh[DIR_CACHE_SIZE]; + struct buffer_head **bh; unsigned int num_entries; };
+#define IS_DYNAMIC_ES(es) ((es)->__bh != (es)->bh) + struct exfat_dir_entry { struct exfat_chain dir; int entry;