From: Takashi Iwai tiwai@suse.de

stable inclusion from stable-v6.6.58 commit 66029078fee00646e2e9dbb8f41ff7819f8e7569 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB0ENI CVE: CVE-2024-50074

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit 02ac3a9ef3a18b58d8f3ea2b6e46de657bf6c4f9 upstream.

The recent fix for array out-of-bounds accesses replaced sprintf() calls blindly with snprintf(). However, since snprintf() returns the would-be-printed size, not the actually output size, the length calculation can still go over the given limit.

Use scnprintf() instead of snprintf(), which returns the actually output letters, for addressing the potential out-of-bounds access properly.

Fixes: ab11dac93d2d ("dev/parport: fix the array out-of-bounds risk") Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de Link: https://lore.kernel.org/r/20240920103318.19271-1-tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yipeng Zou zouyipeng@huawei.com --- drivers/parport/procfs.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/parport/procfs.c b/drivers/parport/procfs.c index c334ef6e3b3f..3b7d7e23602a 100644 --- a/drivers/parport/procfs.c +++ b/drivers/parport/procfs.c @@ -58,12 +58,12 @@ static int do_active_device(struct ctl_table *table, int write, for (dev = port->devices; dev ; dev = dev->next) { if(dev == port->cad) { - len += snprintf(buffer, sizeof(buffer), "%s\n", dev->name); + len += scnprintf(buffer, sizeof(buffer), "%s\n", dev->name); } }

if(!len) { - len += snprintf(buffer, sizeof(buffer), "%s\n", "none"); + len += scnprintf(buffer, sizeof(buffer), "%s\n", "none"); }

if (len > *lenp) @@ -94,19 +94,19 @@ static int do_autoprobe(struct ctl_table *table, int write, } if ((str = info->class_name) != NULL) - len += snprintf (buffer + len, sizeof(buffer) - len, "CLASS:%s;\n", str); + len += scnprintf (buffer + len, sizeof(buffer) - len, "CLASS:%s;\n", str);

if ((str = info->model) != NULL) - len += snprintf (buffer + len, sizeof(buffer) - len, "MODEL:%s;\n", str); + len += scnprintf (buffer + len, sizeof(buffer) - len, "MODEL:%s;\n", str);

if ((str = info->mfr) != NULL) - len += snprintf (buffer + len, sizeof(buffer) - len, "MANUFACTURER:%s;\n", str); + len += scnprintf (buffer + len, sizeof(buffer) - len, "MANUFACTURER:%s;\n", str);

if ((str = info->description) != NULL) - len += snprintf (buffer + len, sizeof(buffer) - len, "DESCRIPTION:%s;\n", str); + len += scnprintf (buffer + len, sizeof(buffer) - len, "DESCRIPTION:%s;\n", str);

if ((str = info->cmdset) != NULL) - len += snprintf (buffer + len, sizeof(buffer) - len, "COMMAND SET:%s;\n", str); + len += scnprintf (buffer + len, sizeof(buffer) - len, "COMMAND SET:%s;\n", str);

if (len > *lenp) len = *lenp; @@ -135,7 +135,7 @@ static int do_hardware_base_addr(struct ctl_table *table, int write, if (write) /* permissions prevent this anyway */ return -EACCES;

- len += snprintf (buffer, sizeof(buffer), "%lu\t%lu\n", port->base, port->base_hi); + len += scnprintf (buffer, sizeof(buffer), "%lu\t%lu\n", port->base, port->base_hi);

if (len > *lenp) len = *lenp; @@ -162,7 +162,7 @@ static int do_hardware_irq(struct ctl_table *table, int write, if (write) /* permissions prevent this anyway */ return -EACCES;

- len += snprintf (buffer, sizeof(buffer), "%d\n", port->irq); + len += scnprintf (buffer, sizeof(buffer), "%d\n", port->irq);

if (len > *lenp) len = *lenp; @@ -189,7 +189,7 @@ static int do_hardware_dma(struct ctl_table *table, int write, if (write) /* permissions prevent this anyway */ return -EACCES;

- len += snprintf (buffer, sizeof(buffer), "%d\n", port->dma); + len += scnprintf (buffer, sizeof(buffer), "%d\n", port->dma);

if (len > *lenp) len = *lenp; @@ -220,7 +220,7 @@ static int do_hardware_modes(struct ctl_table *table, int write, #define printmode(x) \ do { \ if (port->modes & PARPORT_MODE_##x) \ - len += snprintf(buffer + len, sizeof(buffer) - len, "%s%s", f++ ? "," : "", #x); \ + len += scnprintf(buffer + len, sizeof(buffer) - len, "%s%s", f++ ? "," : "", #x); \ } while (0) int f = 0; printmode(PCSPP);