• Jason Baron's avatar
    hwmon: (nct7904) Correct divide by 0 · 8aebbbb2
    Jason Baron authored
    We hit a kernel panic due to a divide by 0 in nct7904_read_fan() for
    the hwmon_fan_min case. Extend the check to hwmon_fan_input case as well
    for safety.
    
    [ 1656.545650] divide error: 0000 [#1] SMP PTI
    [ 1656.545779] CPU: 12 PID: 18010 Comm: sensors Not tainted 5.4.47 #1
    [ 1656.546065] RIP: 0010:nct7904_read+0x1e9/0x510 [nct7904]
    ...
    [ 1656.546549] RAX: 0000000000149970 RBX: ffffbd6b86bcbe08 RCX: 0000000000000000
    ...
    [ 1656.547548] Call Trace:
    [ 1656.547665]  hwmon_attr_show+0x32/0xd0 [hwmon]
    [ 1656.547783]  dev_attr_show+0x18/0x50
    [ 1656.547898]  sysfs_kf_seq_show+0x99/0x120
    [ 1656.548013]  seq_read+0xd8/0x3e0
    [ 1656.548127]  vfs_read+0x89/0x130
    [ 1656.548234]  ksys_read+0x7d/0xb0
    [ 1656.548342]  do_syscall_64+0x48/0x110
    [ 1656.548451]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
    
    Fixes: d65a5102 ("hwmon: (nct7904) Convert to use new hwmon registration API")
    Signed-off-by: default avatarJason Baron <jbaron@akamai.com>
    Link: https://lore.kernel.org/r/1598026814-2604-1-git-send-email-jbaron@akamai.comSigned-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
    8aebbbb2
nct7904.c 30.9 KB