@@ -32,6 +32,7 @@
#include <linux/pagemap.h>
#include "nilfs.h"
#include "page.h"
+#include <linux/ratelimit.h>
static inline unsigned int nilfs_rec_len_from_disk(__le16 dlen)
{
@@ -115,6 +116,7 @@ static bool nilfs_check_folio(struct folio *folio, char *kaddr)
size_t limit = folio_size(folio);
struct nilfs_dir_entry *p;
char *error;
+ static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL * 5, 1);
if (dir->i_size < folio_pos(folio) + limit) {
limit = dir->i_size - folio_pos(folio);
@@ -148,9 +150,11 @@ static bool nilfs_check_folio(struct folio *folio, char *kaddr)
/* Too bad, we had an error */
Ebadsize:
- nilfs_error(sb,
- "size of directory #%lu is not a multiple of chunk size",
- dir->i_ino);
+ if (__ratelimit(&rs)) {
+ nilfs_error(sb,
+ "size of directory #%lu is not a multiple of chunk size",
+ dir->i_ino);
+ }
goto fail;
Eshort:
error = "rec_len is smaller than minimal";
@@ -167,18 +171,22 @@ static bool nilfs_check_folio(struct folio *folio, char *kaddr)
Einumber:
error = "disallowed inode number";
bad_entry:
- nilfs_error(sb,
+ if (__ratelimit(&rs)) {
+ nilfs_error(sb,
"bad entry in directory #%lu: %s - offset=%lu, inode=%lu, rec_len=%zd, name_len=%d",
dir->i_ino, error, (folio->index << PAGE_SHIFT) + offs,
(unsigned long)le64_to_cpu(p->inode),
rec_len, p->name_len);
+ }
goto fail;
Eend:
p = (struct nilfs_dir_entry *)(kaddr + offs);
- nilfs_error(sb,
- "entry in directory #%lu spans the page boundary offset=%lu, inode=%lu",
- dir->i_ino, (folio->index << PAGE_SHIFT) + offs,
- (unsigned long)le64_to_cpu(p->inode));
+ if (__ratelimit(&rs)) {
+ nilfs_error(sb,
+ "entry in directory #%lu spans the page boundary offset=%lu, inode=%lu",
+ dir->i_ino, (folio->index << PAGE_SHIFT) + offs,
+ (unsigned long)le64_to_cpu(p->inode));
+ }
fail:
return false;
}
Syzbot report a task hung in vcs_open. When rec_len too small in nilfs_check_folio, it can result in a huge flood of messages being sent to the console. It eventually caused tty to hung when retrieving the console_lock(). Reported-by: syzbot+8a192e8d090fa9a31135@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8a192e8d090fa9a31135 Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com> --- fs/nilfs2/dir.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-)