Re: [pacman-dev] [PATCH] pacman/callback: fix buffer over-read
Hi, Thanks for the review! > Ok, but maybe we should remove the now redundant null termination after > the if block. > > I believe the '\0' character after the if block is not completely redundant, it terminates the stripped package name which can be shorter than the original string. `len` is modified according to this operation. I'm moving the mentioned line inside the if statement. -- László Várady
Re: [pacman-dev] [PATCH] pacman/callback: fix buffer over-read
On Sat, Aug 03, 2019 at 01:27:35AM +0200, László Várady wrote: > Commit 11ab9aa9f5f0f3873df89c73e8715b82f485bd9b replaced a strcpy() call > with memcpy(), without copying the terminating null character. > > Since fname is allocated with malloc(), subsequent strstr() calls will > overrun the buffer's boundary. > > Signed-off-by: László Várady > --- > src/pacman/callback.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/src/pacman/callback.c b/src/pacman/callback.c > index 22865614..a4c637ce 100644 > --- a/src/pacman/callback.c > +++ b/src/pacman/callback.c > @@ -765,7 +765,7 @@ void cb_dl_progress(const char *filename, off_t > file_xfered, off_t file_total) > > len = strlen(filename); > fname = malloc(len + 1); > - memcpy(fname, filename, len); > + memcpy(fname, filename, len + 1); Ok, but maybe we should remove the now redundant null termination after the if block. > /* strip package or DB extension for cleaner look */ > if((p = strstr(fname, ".pkg")) || (p = strstr(fname, ".db")) || (p = > strstr(fname, ".files"))) { > /* tack on a .sig suffix for signatures */ > -- > 2.22.0
Re: [pacman-dev] [PATCH] pacman/callback: fix buffer over-read
On 08/03/19 at 01:27am, László Várady wrote: > Commit 11ab9aa9f5f0f3873df89c73e8715b82f485bd9b replaced a strcpy() call > with memcpy(), without copying the terminating null character. > > Since fname is allocated with malloc(), subsequent strstr() calls will > overrun the buffer's boundary. > > Signed-off-by: László Várady ACK.
[pacman-dev] [PATCH] pacman/callback: fix buffer over-read
Commit 11ab9aa9f5f0f3873df89c73e8715b82f485bd9b replaced a strcpy() call with memcpy(), without copying the terminating null character. Since fname is allocated with malloc(), subsequent strstr() calls will overrun the buffer's boundary. Signed-off-by: László Várady --- src/pacman/callback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/pacman/callback.c b/src/pacman/callback.c index 22865614..a4c637ce 100644 --- a/src/pacman/callback.c +++ b/src/pacman/callback.c @@ -765,7 +765,7 @@ void cb_dl_progress(const char *filename, off_t file_xfered, off_t file_total) len = strlen(filename); fname = malloc(len + 1); - memcpy(fname, filename, len); + memcpy(fname, filename, len + 1); /* strip package or DB extension for cleaner look */ if((p = strstr(fname, ".pkg")) || (p = strstr(fname, ".db")) || (p = strstr(fname, ".files"))) { /* tack on a .sig suffix for signatures */ -- 2.22.0