Commit-ID: 783ee43118dc773bc8b0342c5b230e017d5a04d0
Gitweb: http://git.kernel.org/tip/783ee43118dc773bc8b0342c5b230e017d5a04d0
Author: Andrzej Zaborowski <andrew.zaborowski@xxxxxxxxx>
AuthorDate: Mon, 9 Jun 2014 16:50:40 +0200
Committer: Matt Fleming <matt.fleming@xxxxxxxxx>
CommitDate: Fri, 27 Jun 2014 07:30:32 +0100
efi-pstore: Fix an overflow on 32-bit builds
In generic_id the long int timestamp is multiplied by 100000 and needs
an explicit cast to u64.
Without that the id in the resulting pstore filename is wrong and
userspace may have problems parsing it, but more importantly files in
pstore can never be deleted and may fill the EFI flash (brick device?).
This happens because when generic pstore code wants to delete a file,
it passes the id to the EFI backend which reinterpretes it and a wrong
variable name is attempted to be deleted. There's no error message but
after remounting pstore, deleted files would reappear.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@xxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Matt Fleming <matt.fleming@xxxxxxxxx>
---
drivers/firmware/efi/efi-pstore.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index 4b9dc83..e992abc 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -40,7 +40,7 @@ struct pstore_read_data {
static inline u64 generic_id(unsigned long timestamp,
unsigned int part, int count)
{
- return (timestamp * 100 + part) * 1000 + count;
+ return ((u64) timestamp * 100 + part) * 1000 + count;
}
static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|