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authorTomas Winkler <tomas.winkler@intel.com>2017-06-12 12:15:55 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-06-13 16:46:18 +0300
commit99c06866bc64a79ec5cf9b9e73fb7c1ba4b3551a (patch)
tree302e91e47e91077fd84f179861b4e5d8a1403000 /drivers/misc
parentf85e8813b2c9346821e704c175d8933d25410331 (diff)
downloadlinux-99c06866bc64a79ec5cf9b9e73fb7c1ba4b3551a.tar.xz
mei: validate the message header only in first fragment.
RX message header is received in the first fragment of the message and saved side and it is not modified after that, we don't need to validate it upon each fragment. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/misc')
-rw-r--r--drivers/misc/mei/interrupt.c26
1 files changed, 19 insertions, 7 deletions
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index c14e35201721..b0b8f18a85e3 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -235,6 +235,17 @@ static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
}
+static inline int hdr_is_valid(u32 msg_hdr)
+{
+ struct mei_msg_hdr *mei_hdr;
+
+ mei_hdr = (struct mei_msg_hdr *)&msg_hdr;
+ if (!msg_hdr || mei_hdr->reserved)
+ return -EBADMSG;
+
+ return 0;
+}
+
/**
* mei_irq_read_handler - bottom half read routine after ISR to
* handle the read processing.
@@ -256,17 +267,18 @@ int mei_irq_read_handler(struct mei_device *dev,
dev->rd_msg_hdr = mei_read_hdr(dev);
(*slots)--;
dev_dbg(dev->dev, "slots =%08x.\n", *slots);
- }
- mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
- dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
- if (mei_hdr->reserved || !dev->rd_msg_hdr) {
- dev_err(dev->dev, "corrupted message header 0x%08X\n",
+ ret = hdr_is_valid(dev->rd_msg_hdr);
+ if (ret) {
+ dev_err(dev->dev, "corrupted message header 0x%08X\n",
dev->rd_msg_hdr);
- ret = -EBADMSG;
- goto end;
+ goto end;
+ }
}
+ mei_hdr = (struct mei_msg_hdr *)&dev->rd_msg_hdr;
+ dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
+
if (mei_slots2data(*slots) < mei_hdr->length) {
dev_err(dev->dev, "less data available than length=%08x.\n",
*slots);