Commit:     059819a41d4331316dd8ddcf977a24ab338f4300
Parent:     266d4f40370757459f8aa063976c932d0de5e59b
Author:     Marcel Holtmann <[EMAIL PROTECTED]>
AuthorDate: Tue Mar 6 22:12:00 2007 +0100
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Tue Mar 6 18:01:04 2007 -0800

    [PATCH] Fix buffer overflow in Omnikey CardMan 4040 driver (CVE-2007-0005)
    Based on a patch from Don Howard <[EMAIL PROTECTED]>
    When calling write() with a buffer larger than 512 bytes, the
    driver's write buffer overflows, allowing to overwrite the EIP and
    execute arbitrary code with kernel privileges.
    In read(), there exists a similar problem, but coming from the device.
    A malicous or buggy device sending more than 512 bytes can overflow
    of the driver's read buffer, with the same effects as above.
    Signed-off-by: Marcel Holtmann <[EMAIL PROTECTED]>
    Signed-off-by: Harald Welte <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
 drivers/char/pcmcia/cm4040_cs.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/char/pcmcia/cm4040_cs.c b/drivers/char/pcmcia/cm4040_cs.c
index 0e82968..f2e4ec4 100644
--- a/drivers/char/pcmcia/cm4040_cs.c
+++ b/drivers/char/pcmcia/cm4040_cs.c
@@ -273,6 +273,7 @@ static ssize_t cm4040_read(struct file *filp, char __user 
        DEBUGP(6, dev, "BytesToRead=%lu\n", bytes_to_read);
        min_bytes_to_read = min(count, bytes_to_read + 5);
+       min_bytes_to_read = min_t(size_t, min_bytes_to_read, 
        DEBUGP(6, dev, "Min=%lu\n", min_bytes_to_read);
@@ -340,7 +341,7 @@ static ssize_t cm4040_write(struct file *filp, const char 
__user *buf,
                return 0;
-       if (count < 5) {
+       if ((count < 5) || (count > READ_WRITE_BUFFER_SIZE)) {
                DEBUGP(2, dev, "<- cm4040_write buffersize=%Zd < 5\n", count);
                return -EIO;
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at

Reply via email to