[PATCH] hfsplus: in case match_strdup() fails to alloc mem inhfsplus_parse_options(), don't blow up.

From: Jesper Juhl
Date: Tue Apr 22 2008 - 17:28:19 EST


From: Jesper Juhl <jesper.juhl@xxxxxxxxx>

The Coverity checker spotted that we do not check the return value of
match_strdup() in fs/hfsplus/options.c::hfsplus_parse_options().
This is bad since match_strdup() does a memory allocation internally
which can fail. If it does fail it will return NULL and in that case
we will 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 in case this happens.

Signed-off-by: Jesper Juhl <jesper.juhl@xxxxxxxxx>
---

options.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/fs/hfsplus/options.c b/fs/hfsplus/options.c
index dc64fac..c9c2f86 100644
--- a/fs/hfsplus/options.c
+++ b/fs/hfsplus/options.c
@@ -132,6 +132,10 @@ int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
return 0;
}
p = match_strdup(&args[0]);
+ if (!p) {
+ printk(KERN_ERR "hfs: match_strdup() memory allocation failed\n");
+ return 0;
+ }
sbi->nls = load_nls(p);
if (!sbi->nls) {
printk(KERN_ERR "hfs: unable to load nls mapping \"%s\"\n", p);


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