Messages in this thread | | | Date | Tue, 27 Feb 2024 20:40:40 +0100 | Subject | Re: [PATCH] wifi: brcm80211: handle pmk_op allocation failure | From | Arend van Spriel <> |
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On 2/27/2024 12:42 PM, Joe Perches wrote: > On Tue, 2024-02-27 at 12:21 +0100, Arend van Spriel wrote: >> On 2/27/2024 9:06 AM, Duoming Zhou wrote: >>> The kzalloc() in brcmf_pmksa_v3_op() will return null if the >>> physical memory has run out. As a result, if we dereference >>> the null value, the null pointer dereference bug will happen. >>> >>> Return -ENOMEM from brcmf_pmksa_v3_op() if kzalloc() fails >>> for pmk_op. >> >> NAK (see below) >> >> Also this issue was reported earlier by Joe Perches. Not sure if he >> wants to be mentioned as such. > > I think it's unimportant to be mentioned. > > I think it's more important that the code be researched > that the simple return of -ENOMEM the appropriate fix > and is handled by all possible callers of the function.
Right. That is what I did after which I replied on Feb 18 to your email.
https://lore.kernel.org/all/3e1f11b3-a689-4c8e-bfda-b43649db7106@broadcom.com/
Regards, Arend
>> >>> Fixes: a96202acaea4 ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3 operations") >>> Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> >>> --- >>> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 5 +++++ >>> 1 file changed, 5 insertions(+) >>> >>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.cq b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> index 28d6a30cc01..3b420b33188 100644 >>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> @@ -4322,6 +4322,10 @@ brcmf_pmksa_v3_op(struct brcmf_if *ifp, struct cfg80211_pmksa *pmksa, >>> int ret; >>> >>> pmk_op = kzalloc(sizeof(*pmk_op), GFP_KERNEL); >>> + if (!pmk_op) { >>> + ret = -ENOMEM; >>> + goto out; >>> + } >> >> There is really no need to introduce a new label for this. Although you >> can kfree() a NULL pointer there is no need to do so when you know >> already it is NULL. Just return -ENOMEM and be done with it. >> >> Regards, >> Arend >> >>> pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3); >>> >>> if (!pmksa) { >>> @@ -4340,6 +4344,7 @@ brcmf_pmksa_v3_op(struct brcmf_if *ifp, struct cfg80211_pmksa *pmksa, >>> pmk_op->length = cpu_to_le16(length); >>> >>> ret = brcmf_fil_iovar_data_set(ifp, "pmkid_info", pmk_op, sizeof(*pmk_op)); >>> +out: >>> kfree(pmk_op); >>> return ret; >>> } > [unhandled content-type:application/pkcs7-signature] | |