In the Linux kernel, the following vulnerability has been resolved:
jfs: fix slab-out-of-bounds read in ea_get()
During the "size_check" label in ea_get(), the code checks if the extended
attribute list (xattr) size matches ea_size. If not, it logs
"ea_get: invalid extended attribute" and calls print_hex_dump().
Here, EALIST_SIZE(ea_buf->xattr) returns 4110417968, which exceeds
INT_MAX (2,147,483,647). Then ea_size is clamped:
int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr));
Although clamp_t aims to bound ea_size between 0 and 4110417968, the upper
limit is treated as an int, causing an overflow above 2^31 - 1. This leads
"size" to wrap around and become negative (-184549328).
The "size" is then passed to print_hex_dump() (called "len" in
print_hex_dump()), it is passed as type size_t (an unsigned
type), this is then stored inside a variable called
"int remaining", which is then assigned to "int linelen" which
is then passed to hex_dump_to_buffer(). In print_hex_dump()
the for loop, iterates through 0 to len-1, where len is
18446744073525002176, calling hex_dump_to_buffer()
on each iteration:
for (i = 0; i < len; i += rowsize) {
linelen = min(remaining, rowsize);
remaining -= rowsize;
hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
linebuf, sizeof(linebuf), ascii);
...
}
The expected stopping condition (i < len) is effectively broken
since len is corrupted and very large. This eventually leads to
the "ptr+i" being passed to hex_dump_to_buffer() to get closer
to the end of the actual bounds of "ptr", eventually an out of
bounds access is done in hex_dump_to_buffer() in the following
for loop:
for (j = 0; j < len; j++) {
if (linebuflen < lx + 2)
goto overflow2;
ch = ptr[j];
...
}
To fix this we should validate "EALIST_SIZE(ea_buf->xattr)"
before it is utilised.
References
Configurations
Configuration 1 (hide)
|
History
28 Apr 2025, 14:37
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/0beddc2a3f9b9cf7d8887973041e36c2d0fa3652 - Patch | |
| References | () https://git.kernel.org/stable/c/16d3d36436492aa248b2d8045e75585ebcc2f34d - Patch | |
| References | () https://git.kernel.org/stable/c/3d6fd5b9c6acbc005e53d0211c7381f566babec1 - Patch | |
| References | () https://git.kernel.org/stable/c/46e2c031aa59ea65128991cbca474bd5c0c2ecdb - Patch | |
| References | () https://git.kernel.org/stable/c/50afcee7011155933d8d5e8832f52eeee018cfd3 - Patch | |
| References | () https://git.kernel.org/stable/c/5263822558a8a7c0d0248d5679c2dcf4d5cda61f - Patch | |
| References | () https://git.kernel.org/stable/c/78c9cbde8880ec02d864c166bcb4fe989ce1d95f - Patch | |
| References | () https://git.kernel.org/stable/c/a8c31808925b11393a6601f534bb63bac5366bab - Patch | |
| References | () https://git.kernel.org/stable/c/fdf480da5837c23b146c4743c18de97202fcab37 - Patch | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.1 |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| First Time |
Linux linux Kernel
Linux |
|
| CWE | CWE-125 | |
| Summary |
|
18 Apr 2025, 07:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2025-04-18 07:15
Updated : 2025-04-28 14:37
NVD link : CVE-2025-39735
Mitre link : CVE-2025-39735
CVE.ORG link : CVE-2025-39735
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-125
Out-of-bounds Read