Re: [PATCH v2 4/4] venus: hfi_parser: Add check to keep the number of codecs within range

From: Bryan O'Donoghue
Date: Fri Aug 11 2023 - 04:43:07 EST


On 11/08/2023 07:04, Vikash Garodia wrote:

On 8/10/2023 5:03 PM, Bryan O'Donoghue wrote:
On 10/08/2023 03:25, Vikash Garodia wrote:
+    if (hweight_long(core->dec_codecs) + hweight_long(core->enc_codecs) >
MAX_CODEC_NUM)
+        return;
+

Shouldn't this be >= ?
Not needed. Lets take a hypothetical case when core->dec_codecs has initial 16
(0-15) bits set and core->enc_codecs has next 16 bits (16-31) set. The bit count
would be 32. The codec loop after this check would run on caps array index 0-31.
I do not see a possibility for OOB access in this case.


struct hfi_plat_caps caps[MAX_CODEC_NUM];

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bod


Are you not doing a general defensive coding pass in this series ie

"[PATCH v2 2/4] venus: hfi: fix the check to handle session buffer requirement"

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bod