Re: [U-Boot] [PATCH] fs/fat: fix fatbuf leak

On 09/12/2017 10:40 PM, Rob Clark wrote:

A new fatbuf was allocated by get_fs_info() (called by fat_itr_root()), but not freed, resulting in eventually running out of memory. Spotted by running 'ls -r' in a large FAT filesystem from Shell.efi.

fatbuf is mainly used to cache FAT entry lookups (get_fatent()).. possibly once fat_write.c it can move into the iterator to simplify this.

Signed-off-by: Rob Clark robdclark@gmail.com

I can squash this back in to the earlier readdir patches and resend them if that is preferred.

fs/fat/fat.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/fs/fat/fat.c b/fs/fat/fat.c index f5f74c12ff..f0284398b4 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -1042,6 +1042,7 @@ int fat_exists(const char *filename) return 0;

ret = fat_itr_resolve(itr, filename, TYPE_ANY);

• free(fsdata.fatbuf); return ret == 0; }

@@ -1061,17 +1062,19 @@ int fat_size(const char *filename, loff_t *size) * Directories don't have size, but fs_size() is not * expected to fail if passed a directory path: */

• free(fsdata.fatbuf);
  

  fat_itr_root(itr, &fsdata); if (!fat_itr_resolve(itr, filename, TYPE_DIR)) { *size = 0;

• 	return 0;
  

• 	ret = 0;
  

  }

• return ret;
  

• goto out;
  

  }

  *size = FAT2CPU32(itr->dent->size);

• return 0;

+out:

• free(fsdata.fatbuf);

• return ret; }

  int file_fat_read_at(const char *filename, loff_t pos, void *buffer,

@@ -1087,10 +1090,14 @@ int file_fat_read_at(const char *filename, loff_t pos, void *buffer,

ret = fat_itr_resolve(itr, filename, TYPE_FILE); if (ret)

• return ret;
  

• goto out;
  
  

  printf("reading %s\n", filename);

• return get_contents(&fsdata, itr->dent, pos, buffer, maxsize, actread);

• ret = get_contents(&fsdata, itr->dent, pos, buffer, maxsize, actread);

+out:

• free(fsdata.fatbuf);

• return ret; }

  int file_fat_read(const char *filename, void *buffer, int maxsize)

@@ -1126,7 +1133,7 @@ typedef struct {

int fat_opendir(const char *filename, struct fs_dir_stream **dirsp) {

• fat_dir *dir = malloc(sizeof(*dir));

• fat_dir *dir = calloc(1, sizeof(*dir)); int ret;

  if (!dir)

@@ -1144,6 +1151,7 @@ int fat_opendir(const char *filename, struct fs_dir_stream **dirsp) return 0;

fail:

• free(dir->fsdata.fatbuf); free(dir); return ret; }

@@ -1174,6 +1182,7 @@ int fat_readdir(struct fs_dir_stream *dirs, struct fs_dirent **dentp) void fat_closedir(struct fs_dir_stream *dirs) { fat_dir *dir = (fat_dir *)dirs;

• free(dir->fsdata.fatbuf); free(dir); }

Reviewed-by: Łukasz Majewski lukma@denx.de