From: Gao Feng <fgao@xxxxxxxxxx> Subject: proc/sysctl: fix the int overflow for jiffies conversion do_proc_dointvec_jiffies_conv() uses LONG_MAX/HZ as the max value to avoid overflow. But actually the *valp is int type, so it still causes overflow. For example, echo 2147483647 > ./sys/net/ipv4/tcp_keepalive_time Then, cat ./sys/net/ipv4/tcp_keepalive_time The output is "-1", it is not expected. Now use INT_MAX/HZ as the max value instead LONG_MAX/HZ to fix it. Link: http://lkml.kernel.org/r/1490109532-9228-1-git-send-email-fgao@xxxxxxxxxx Signed-off-by: Gao Feng <fgao@xxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx> Cc: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/sysctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN kernel/sysctl.c~proc-sysctl-fix-the-int-overflow-for-jiffies-conversion kernel/sysctl.c --- a/kernel/sysctl.c~proc-sysctl-fix-the-int-overflow-for-jiffies-conversion +++ a/kernel/sysctl.c @@ -2576,7 +2576,7 @@ static int do_proc_dointvec_jiffies_conv int write, void *data) { if (write) { - if (*lvalp > LONG_MAX / HZ) + if (*lvalp > INT_MAX / HZ) return 1; *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); } else { _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
