4.19-stable review patch. If anyone has any objections, please let me know.
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From: Mauro Carvalho Chehab mchehab+huawei@kernel.org
commit 14a22762c3daeac59a5a534e124acbb4d7a79b3a upstream.
The current logic allows word to be less than 2. If this happens, there will be buffer overflows, as reported by smatch. Add extra checks to prevent it.
While here, remove an unused word = 0 assignment.
Fixes: 6c96dbbc2aa9 ("[media] s5p-jpeg: add support for 5433") Cc: stable@vger.kernel.org Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Reviewed-by: Jacek Anaszewski jacek.anaszewski@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/platform/s5p-jpeg/jpeg-core.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-)
--- a/drivers/media/platform/s5p-jpeg/jpeg-core.c +++ b/drivers/media/platform/s5p-jpeg/jpeg-core.c @@ -803,11 +803,14 @@ static void exynos4_jpeg_parse_decode_h_ (unsigned long)vb2_plane_vaddr(&vb->vb2_buf, 0) + ctx->out_q.sos + 2; jpeg_buffer.curr = 0;
- word = 0; - if (get_word_be(&jpeg_buffer, &word)) return; - jpeg_buffer.size = (long)word - 2; + + if (word < 2) + jpeg_buffer.size = 0; + else + jpeg_buffer.size = (long)word - 2; + jpeg_buffer.data += 2; jpeg_buffer.curr = 0;
@@ -1086,6 +1089,7 @@ static int get_word_be(struct s5p_jpeg_b if (byte == -1) return -1; *word = (unsigned int)byte | temp; + return 0; }
@@ -1173,7 +1177,7 @@ static bool s5p_jpeg_parse_hdr(struct s5 if (get_word_be(&jpeg_buffer, &word)) break; length = (long)word - 2; - if (!length) + if (length <= 0) return false; sof = jpeg_buffer.curr; /* after 0xffc0 */ sof_len = length; @@ -1204,7 +1208,7 @@ static bool s5p_jpeg_parse_hdr(struct s5 if (get_word_be(&jpeg_buffer, &word)) break; length = (long)word - 2; - if (!length) + if (length <= 0) return false; if (n_dqt >= S5P_JPEG_MAX_MARKER) return false; @@ -1217,7 +1221,7 @@ static bool s5p_jpeg_parse_hdr(struct s5 if (get_word_be(&jpeg_buffer, &word)) break; length = (long)word - 2; - if (!length) + if (length <= 0) return false; if (n_dht >= S5P_JPEG_MAX_MARKER) return false; @@ -1242,6 +1246,7 @@ static bool s5p_jpeg_parse_hdr(struct s5 if (get_word_be(&jpeg_buffer, &word)) break; length = (long)word - 2; + /* No need to check underflows as skip() does it */ skip(&jpeg_buffer, length); break; }