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| author | Bjorn Helgaas <bjorn.helgaas@hp.com> | 2010-01-07 12:58:51 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-04-26 07:41:32 -0700 |
| commit | 8bb98f7cae996013a2cf1ccd4bc375b8189b52e9 (patch) | |
| tree | bc15c1aaff080d8949a5cc33a536cb2a2e2d6723 /drivers | |
| parent | fca6a735cc3b070a25c3fa2b09073ff836307d24 (diff) | |
| download | lwn-8bb98f7cae996013a2cf1ccd4bc375b8189b52e9.tar.gz lwn-8bb98f7cae996013a2cf1ccd4bc375b8189b52e9.zip | |
agp/hp: fixup hp agp after ACPI changes
commit 67fe63b0715ccfaefa0af8a6e705c5470ee5cada upstream.
Commit 15b8dd53f5ffa changed the string in info->hardware_id from a static
array to a pointer and added a length field. But instead of changing
"sizeof(array)" to "length", we changed it to "sizeof(length)" (== 4),
which corrupts the string we're trying to null-terminate.
We no longer even need to null-terminate the string, but we *do* need to
check whether we found a HID. If there's no HID, we used to have an empty
array, but now we have a null pointer.
The combination of these defects causes this oops:
Unable to handle kernel NULL pointer dereference (address 0000000000000003)
modprobe[895]: Oops 8804682956800 [1]
ip is at zx1_gart_probe+0xd0/0xcc0 [hp_agp]
http://marc.info/?l=linux-ia64&m=126264484923647&w=2
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reported-by: Émeric Maschino <emeric.maschino@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/char/agp/hp-agp.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/char/agp/hp-agp.c b/drivers/char/agp/hp-agp.c index 9047b2714653..dc8a6f70483b 100644 --- a/drivers/char/agp/hp-agp.c +++ b/drivers/char/agp/hp-agp.c @@ -488,9 +488,8 @@ zx1_gart_probe (acpi_handle obj, u32 depth, void *context, void **ret) handle = obj; do { status = acpi_get_object_info(handle, &info); - if (ACPI_SUCCESS(status)) { + if (ACPI_SUCCESS(status) && (info->valid & ACPI_VALID_HID)) { /* TBD check _CID also */ - info->hardware_id.string[sizeof(info->hardware_id.length)-1] = '\0'; match = (strcmp(info->hardware_id.string, "HWP0001") == 0); kfree(info); if (match) { |