On Sat, Dec 03, 2022 at 04:40:09AM +0000, Ryder Lee wrote: > On Fri, 2022-12-02 at 14:11 -0800, coverity-bot wrote: > > Hello! > > > > This is an experimental semi-automated report about issues detected > > by > > Coverity from a scan of next-20221202 as part of the linux-next scan > > project: > > > https://urldefense.com/v3/__https://scan.coverity.com/projects/linux-next-weekly-scan__;!!CTRNKA9wMg0ARbw!jBOoj6LMqqA8E0AyjKQTa-0rVzcFiZ3BbpciEIn7so974kcMBeG4zZm-QU4AudLXY7-jNUSt0unzAt2zirSF$ ; > > > > > > You're getting this email because you were associated with the > > identified > > lines of code (noted below) that were touched by commits: > > > > Thu Dec 1 17:29:14 2022 +0100 > > 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi > > 7 (802.11be) devices") > > > > Coverity reported the following: > > > > *** CID 1527813: Integer handling issues (SIGN_EXTENSION) > > drivers/net/wireless/mediatek/mt76/mt7996/debugfs.c:460 in > > mt7996_hw_queue_read() > > 454 for (i = 0; i < size; i++) { > > 455 u32 ctrl, head, tail, queued; > > 456 > > 457 if (val & BIT(map[i].index)) > > 458 continue; > > 459 > > vvv CID 1527813: Integer handling issues (SIGN_EXTENSION) > > vvv Suspicious implicit sign extension: "map[i].qid" with type > > "u8" (8 bits, unsigned) is promoted in "map[i].qid << 24" to type > > "int" (32 bits, signed), then sign-extended to type "unsigned long" > > (64 bits, unsigned). If "map[i].qid << 24" is greater than > > 0x7FFFFFFF, the upper bits of the result will all be 1. > > 460 ctrl = BIT(31) | (map[i].pid << 10) | > > (map[i].qid << 24); > > u32 ctrl = BIT(31) | (map[i].pid << 10) | (map[i].qid << 24); > > Hmm ...where's type "int" (32 bits, signed) from? map[i].qid is promoted to int before the "<< 24". -- Kees Cook
