Messages in this thread Patch in this message | | | Date | Tue, 22 Apr 2008 23:12:27 +0200 (CEST) | Subject | [PATCH] hfs: if match_strdup() fails to allocate memory in parse_options(), don't blow up the kernel. | From | Jesper Juhl <> |
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From: Jesper Juhl <jesper.juhl@gmail.com>
The Coverity checker spotted that we don't check the return value of match_strdup() in fs/hfs/super.c::parse_options(). This is bad since match_strdup() does a memory allocation internally which can fail. If it does fail it'll return NULL and in that case we'll pass the NULL pointer on to load_nls() which will eventually dereference it - Boom! Much better to check the return value, fail gracefully and log an error message if this happens. This happens in two different spots. I've made the error logged in each location unique so that it'll be obvious in bug reports later exactely which one of the two spots got hit (always nice to have grep'able error messages that point to a unique location in the source).
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> ---
super.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 32de44e..221e314 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -297,6 +297,10 @@ static int parse_options(char *options, struct hfs_sb_info *hsb) return 0; } p = match_strdup(&args[0]); + if (!p) { + printk(KERN_ERR "hfs: mem alloc failed in match_strdup()\n"); + return 0; + } hsb->nls_disk = load_nls(p); if (!hsb->nls_disk) { printk(KERN_ERR "hfs: unable to load codepage \"%s\"\n", p); @@ -311,6 +315,10 @@ static int parse_options(char *options, struct hfs_sb_info *hsb) return 0; } p = match_strdup(&args[0]); + if (!p) { + printk(KERN_ERR "hfs: memory allocation failed in match_strdup()\n"); + return 0; + } hsb->nls_io = load_nls(p); if (!hsb->nls_io) { printk(KERN_ERR "hfs: unable to load iocharset \"%s\"\n", p);
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