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From: Andreas Schwab <schwab@linux-m68k.org>
To: Adhemerval Zanella via Glibc-cvs <glibc-cvs@sourceware.org>
Cc: Adhemerval Zanella <azanella@sourceware.org>
Subject: Re: [glibc] malloc: Assure that THP mode is always null terminated
Date: Fri, 14 Apr 2023 08:52:52 +0200	[thread overview]
Message-ID: <87fs93lzuj.fsf@linux-m68k.org> (raw)
In-Reply-To: <20230413201833.21C0C3858D20@sourceware.org> (Adhemerval Zanella via Glibc-cvs's message of "Thu, 13 Apr 2023 20:18:33 +0000 (GMT)")

On Apr 13 2023, Adhemerval Zanella via Glibc-cvs wrote:

> diff --git a/sysdeps/unix/sysv/linux/malloc-hugepages.c b/sysdeps/unix/sysv/linux/malloc-hugepages.c
> index 683d68c327..740027ebfb 100644
> --- a/sysdeps/unix/sysv/linux/malloc-hugepages.c
> +++ b/sysdeps/unix/sysv/linux/malloc-hugepages.c
> @@ -61,6 +61,7 @@ __malloc_thp_mode (void)
>  
>    char str[sizeof(mode_always)];
>    ssize_t s = __read_nocancel (fd, str, sizeof (str));
> +  str[s] = '\0';

This is a buffer overflow if s >= sizeof (str) or s < 0.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

  reply	other threads:[~2023-04-14  6:52 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-04-13 20:18 Adhemerval Zanella
2023-04-14  6:52 ` Andreas Schwab [this message]
2023-04-14 11:02   ` Adhemerval Zanella

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