From: Pavel Roskin Date: Wed, 25 Oct 2006 02:41:27 +0000 (-0400) Subject: [PATCH] hostap_plx: fix CIS verification X-Git-Tag: v2.6.19-rc5~10^2^2~2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=115e222d538e7838bffa0f76409acd9816a0ef32;p=linux-2.6 [PATCH] hostap_plx: fix CIS verification The length of the manfid CIS should be at least 4, and it's normally 4. It's incorrect to require it to be at least 5. This breaks support for most (if not all) cards. The right place to ensure that we don't access beyond the CIS buffer is to strengthen another check. Make sure that the next tuple begins at least at the CIS buffer end (in which case we stop processing) or before that. Reported by ph35sm@free.fr Signed-off-by: Pavel Roskin Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/hostap/hostap_plx.c b/drivers/net/wireless/hostap/hostap_plx.c index 6dfa041be6..bc81b13a5a 100644 --- a/drivers/net/wireless/hostap/hostap_plx.c +++ b/drivers/net/wireless/hostap/hostap_plx.c @@ -364,7 +364,7 @@ static int prism2_plx_check_cis(void __iomem *attr_mem, int attr_len, pos = 0; while (pos < CIS_MAX_LEN - 1 && cis[pos] != CISTPL_END) { - if (pos + cis[pos + 1] >= CIS_MAX_LEN) + if (pos + 2 + cis[pos + 1] > CIS_MAX_LEN) goto cis_error; switch (cis[pos]) { @@ -391,7 +391,7 @@ static int prism2_plx_check_cis(void __iomem *attr_mem, int attr_len, break; case CISTPL_MANFID: - if (cis[pos + 1] < 5) + if (cis[pos + 1] < 4) goto cis_error; manfid1 = cis[pos + 2] + (cis[pos + 3] << 8); manfid2 = cis[pos + 4] + (cis[pos + 5] << 8);