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| author | Gleb Natapov <gleb@redhat.com> | 2011-04-26 11:21:32 +0300 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2011-04-27 14:16:12 -0700 |
| commit | 0c61227094b3ddaca2f847ee287c4a2e3762b5a2 (patch) | |
| tree | b9575437608041e1ebce1302ce1fb20902a04656 /drivers/firmware | |
| parent | 8e10cd74342c7f5ce259cceca36f6eba084f5d58 (diff) | |
| download | linux-0c61227094b3ddaca2f847ee287c4a2e3762b5a2.tar.bz2 | |
x86, setup: Fix EDD3.0 data verification.
Check for nonzero path in edd_has_edd30() has no sense. First, it looks
at the wrong memory. Device path starts at offset 30 of the info->params
structure which is at offset 8 from the beginning of info structure,
but code looks at info + 4 instead. This was correct when code was
introduced, but around v2.6.4 three more fields were added to edd_info
structure (commit 66b61a5c in history.git). Second, even if it will check
correct memory it will always succeed since at offset 30 (params->key)
there will be non-zero values otherwise previous check would fail.
The patch replaces this bogus check with one that verifies checksum.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Link: http://lkml.kernel.org/r/20110426082132.GG2265@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/edd.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/drivers/firmware/edd.c b/drivers/firmware/edd.c index 96c25d93eed1..f1b7f659d3c9 100644 --- a/drivers/firmware/edd.c +++ b/drivers/firmware/edd.c @@ -531,8 +531,8 @@ static int edd_has_edd30(struct edd_device *edev) { struct edd_info *info; - int i, nonzero_path = 0; - char c; + int i; + u8 csum = 0; if (!edev) return 0; @@ -544,16 +544,16 @@ edd_has_edd30(struct edd_device *edev) return 0; } - for (i = 30; i <= 73; i++) { - c = *(((uint8_t *) info) + i + 4); - if (c) { - nonzero_path++; - break; - } - } - if (!nonzero_path) { + + /* We support only T13 spec */ + if (info->params.device_path_info_length != 44) + return 0; + + for (i = 30; i < info->params.device_path_info_length + 30; i++) + csum += *(((u8 *)&info->params) + i); + + if (csum) return 0; - } return 1; } |