From: Hans Verkuil hverkuil@xs4all.nl
[ Upstream commit 5edc9b560f60c40e658af0b8e98ae2dfadc438d8 ]
Fix gcc8 warning:
drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c:1014:44: warning: 'DCEC' directive output may be truncated writing 4 bytes into a region of size between 0 and 53 [-Wformat-truncation=]
Resizing the 'buf' and 'cmd' arrays fixed the warning.
Signed-off-by: Ricardo Ribalda ribalda@chromium.org Signed-off-by: Hans Verkuil hverkuil@xs4all.nl Signed-off-by: Sasha Levin sashal@kernel.org ---
NO This commit should not be backported to stable kernel trees for the following reasons: 1. **Non-critical compiler warning fix**: This commit addresses a `-Wformat-truncation` compiler warning, which is a build- time warning and not a runtime bug that affects users. The warning indicates potential string truncation, but looking at the code, there's no evidence this causes actual runtime failures or security vulnerabilities. 2. **Consistent with similar commit patterns**: Looking at the reference commits, all the similar format-truncation warning fixes (commits #1, #2, #3, and #5) were marked as "Backport Status: NO". Only commit #4 was marked "YES", but that one explicitly included "Cc: stable@vger.kernel.org" in the commit message and had a "Fixes:" tag, which this commit lacks. 3. **Missing stable tree indicators**: The commit message contains no "Cc: stable@vger.kernel.org" tag and no "Fixes:" tag pointing to a specific problematic commit that introduced a user-facing issue. 4. **Minor code quality improvement**: The changes are purely preventive: - `char buf[CEC_MAX_MSG_SIZE 0001-Fix-Clippy- warnings.patch 0002-Enhance-inference-prompt-to-utilize-CVEKERNELDIR- whe.patch 0003-Update-to-latest-version-of-clap.patch Cargo.lock Cargo.toml LICENSE README.md adreno_acd_support_analysis.md amd_display_ips_sequential_ono_backport_analysis.md analyze_merge_commit.sh dpp_rcg_backport_analysis.md drm_amd_display_vertical_interrupt_dcn32_dcn401_backport_analysis.md drm_bridge_analysis.txt drm_format_helper_24bit_analysis.md drm_imagination_register_update_analysis.md drm_mediatek_mtk_dpi_refactoring_analysis.md intel_ipu6_constify_analysis.md io_uring_analysis.txt ksmbd_analysis.txt merge_commit_analysis.txt model prompt src target test_gpio_cleanup.txt test_patch.txt verisilicon_av1_4k_analysis.md 3 + 1];` becomes `char buf[(CEC_MAX_MSG_SIZE - 1) 0001-Fix-Clippy-warnings.patch 0002-Enhance- inference-prompt-to-utilize-CVEKERNELDIR-whe.patch 0003-Update-to- latest-version-of-clap.patch Cargo.lock Cargo.toml LICENSE README.md adreno_acd_support_analysis.md amd_display_ips_sequential_ono_backport_analysis.md analyze_merge_commit.sh dpp_rcg_backport_analysis.md drm_amd_display_vertical_interrupt_dcn32_dcn401_backport_analysis.md drm_bridge_analysis.txt drm_format_helper_24bit_analysis.md drm_imagination_register_update_analysis.md drm_mediatek_mtk_dpi_refactoring_analysis.md intel_ipu6_constify_analysis.md io_uring_analysis.txt ksmbd_analysis.txt merge_commit_analysis.txt model prompt src target test_gpio_cleanup.txt test_patch.txt verisilicon_av1_4k_analysis.md 3 + 1];` - `char cmd[CEC_MAX_MSG_SIZE 0001-Fix-Clippy-warnings.patch 0002-Enhance- inference-prompt-to-utilize-CVEKERNELDIR-whe.patch 0003-Update-to- latest-version-of-clap.patch Cargo.lock Cargo.toml LICENSE README.md adreno_acd_support_analysis.md amd_display_ips_sequential_ono_backport_analysis.md analyze_merge_commit.sh dpp_rcg_backport_analysis.md drm_amd_display_vertical_interrupt_dcn32_dcn401_backport_analysis.md drm_bridge_analysis.txt drm_format_helper_24bit_analysis.md drm_imagination_register_update_analysis.md drm_mediatek_mtk_dpi_refactoring_analysis.md intel_ipu6_constify_analysis.md io_uring_analysis.txt ksmbd_analysis.txt merge_commit_analysis.txt model prompt src target test_gpio_cleanup.txt test_patch.txt verisilicon_av1_4k_analysis.md 3 + 13];` becomes `char cmd[sizeof(buf) + 14];` These changes slightly reduce buffer sizes to better match actual usage patterns, but there's no indication the original sizes caused buffer overflows or other runtime problems. 5. **Media subsystem and driver-specific**: This affects a specific USB CEC adapter driver (`extron-da-hd-4k-plus`), making it a relatively isolated change that doesn't impact core kernel functionality or multiple subsystems. 6. **No user-reported issues**: There's no mention of user reports, bug fixes, or functional improvements - only compiler warning suppression. The stable kernel tree rules prioritize important bug fixes with minimal regression risk. This commit, while technically correct, falls into the category of code quality improvements rather than critical fixes that users would benefit from in stable releases.
.../media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c b/drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c index cfbfc4c1b2e67..41d019b01ec09 100644 --- a/drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c +++ b/drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c @@ -1002,8 +1002,8 @@ static int extron_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, u32 signal_free_time, struct cec_msg *msg) { struct extron_port *port = cec_get_drvdata(adap); - char buf[CEC_MAX_MSG_SIZE * 3 + 1]; - char cmd[CEC_MAX_MSG_SIZE * 3 + 13]; + char buf[(CEC_MAX_MSG_SIZE - 1) * 3 + 1]; + char cmd[sizeof(buf) + 14]; unsigned int i;
if (port->disconnected)