From 7f021716f04baf0d3d3709bcb6c2bf4c0a47e8d8 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Wed, 26 Feb 2025 22:49:14 +0900 Subject: [PATCH] media: s5p-jpeg: prevent buffer overflows BugLink: https://bugs.launchpad.net/bugs/2100292 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 Reviewed-by: Jacek Anaszewski Signed-off-by: Greg Kroah-Hartman CVE-2024-53061 Signed-off-by: Koichiro Den Signed-off-by: Stefan Bader --- .../media/platform/samsung/s5p-jpeg/jpeg-core.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c b/drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c index d2c4a0178b3c..1db4609b3557 100644 --- a/drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c +++ b/drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c @@ -775,11 +775,14 @@ static void exynos4_jpeg_parse_decode_h_tbl(struct s5p_jpeg_ctx *ctx) (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; @@ -1058,6 +1061,7 @@ static int get_word_be(struct s5p_jpeg_buffer *buf, unsigned int *word) if (byte == -1) return -1; *word = (unsigned int)byte | temp; + return 0; } @@ -1145,7 +1149,7 @@ static bool s5p_jpeg_parse_hdr(struct s5p_jpeg_q_data *result, 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; @@ -1176,7 +1180,7 @@ static bool s5p_jpeg_parse_hdr(struct s5p_jpeg_q_data *result, 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; @@ -1189,7 +1193,7 @@ static bool s5p_jpeg_parse_hdr(struct s5p_jpeg_q_data *result, 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; @@ -1214,6 +1218,7 @@ static bool s5p_jpeg_parse_hdr(struct s5p_jpeg_q_data *result, 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; }