From: Rasmus Villemoes Date: Thu, 29 Aug 2024 11:01:02 +0000 (+0200) Subject: kern/fs: Honour file->read_hook() in grub_fs_blocklist_read() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4f6c4609174d92c8b881bc5adb7fe971dd5cee0b;p=thirdparty%2Fgrub.git kern/fs: Honour file->read_hook() in grub_fs_blocklist_read() Unlike files accessed via a normal file system, the file->read_hook() is not honoured when using blocklist notation. This means that when trying to use a dedicated, 1 KiB, raw partition for the environment block and hence does something like save_env --file=(hd0,gpt9)0+2 X Y Z this fails with "sparse file not allowed", which is rather unexpected, as I've explicitly said exactly which blocks should be used. Adding a little debugging reveals that grub_file_size(file) is 1024 as expected, but total_length is 0, simply because the callback was never invoked, so blocklists is an empty list. Fix that by honouring the ->read_hook() set by the caller, also when a "file" is specified with blocklist notation. Signed-off-by: Rasmus Villemoes Reviewed-by: Vladimir Serbinenko Reviewed-by: Daniel Kiper --- diff --git a/grub-core/kern/fs.c b/grub-core/kern/fs.c index 7ad0aaf4e..80d325868 100644 --- a/grub-core/kern/fs.c +++ b/grub-core/kern/fs.c @@ -215,12 +215,15 @@ grub_fs_blocklist_read (grub_file_t file, char *buf, grub_size_t len) grub_disk_addr_t sector; grub_off_t offset; grub_ssize_t ret = 0; + grub_disk_t disk = file->device->disk; if (len > file->size - file->offset) len = file->size - file->offset; sector = (file->offset >> GRUB_DISK_SECTOR_BITS); offset = (file->offset & (GRUB_DISK_SECTOR_SIZE - 1)); + disk->read_hook = file->read_hook; + disk->read_hook_data = file->read_hook_data; for (p = file->data; p->length && len > 0; p++) { if (sector < p->length) @@ -232,9 +235,12 @@ grub_fs_blocklist_read (grub_file_t file, char *buf, grub_size_t len) >> GRUB_DISK_SECTOR_BITS) > p->length - sector) size = ((p->length - sector) << GRUB_DISK_SECTOR_BITS) - offset; - if (grub_disk_read (file->device->disk, p->offset + sector, offset, + if (grub_disk_read (disk, p->offset + sector, offset, size, buf) != GRUB_ERR_NONE) - return -1; + { + ret = -1; + break; + } ret += size; len -= size; @@ -244,6 +250,8 @@ grub_fs_blocklist_read (grub_file_t file, char *buf, grub_size_t len) else sector -= p->length; } + disk->read_hook = NULL; + disk->read_hook_data = NULL; return ret; }