• Junhao He's avatar
    perf pmus: Fixes always false when compare duplicates aliases · dd9a426e
    Junhao He authored
    In the previous loop, all the members in the aliases[j-1] have been freed
    and set to NULL. But in this loop, the function pmu_alias_is_duplicate()
    compares the aliases[j] with the aliases[j-1] that has already been
    disposed, so the function will always return false and duplicate aliases
    will never be discarded.
    
    If we find duplicate aliases, it skips the zfree aliases[j], which is
    accompanied by a memory leak.
    
    We can use the next aliases[j+1] to theck for duplicate aliases to
    fixes the aliases NULL pointer dereference, then goto zfree code snippet
    to release it.
    
    After patch testing:
     $ perf list --unit=hisi_sicl,cpa pmu
    
     uncore cpa:
       cpa_p0_rd_dat_32b
            [Number of read ops transmitted by the P0 port which size is 32 bytes.
             Unit: hisi_sicl,cpa]
       cpa_p0_rd_dat_64b
            [Number of read ops transmitted by the P0 port which size is 64 bytes.
             Unit: hisi_sicl,cpa]
    
    Fixes: c3245d20 ("perf pmu: Abstract alias/event struct")
    Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
    Cc: ravi.bangoria@amd.com
    Cc: james.clark@arm.com
    Cc: prime.zeng@hisilicon.com
    Cc: cuigaosheng1@huawei.com
    Cc: jonathan.cameron@huawei.com
    Cc: linuxarm@huawei.com
    Cc: yangyicong@huawei.com
    Cc: robh@kernel.org
    Cc: renyu.zj@linux.alibaba.com
    Cc: kjain@linux.ibm.com
    Cc: john.g.garry@oracle.com
    Cc: linux-arm-kernel@lists.infradead.org
    Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
    Link: https://lore.kernel.org/r/20240614094318.11607-1-hejunhao3@huawei.com
    dd9a426e
pmus.c 17.9 KB